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Revision of Indo-Pacific Species of the Loosejaw Dragonfish Genus
Photostomias (Teleostei: Stomiidae: Malacosteinae)
Christopher P. Kenaley1
Several studies of the ecology of mesopelagic fishes off Hawaii published in the 1970s and 1980s reported the existenceof as many as two undescribed species in the Pacific Ocean. Diagnosed primarily on the basis of postorbital andaccessory orbital photophore size and size at maturity, three new species are described: P. liemi, new species, and P.tantillux, new species, both endemic to tropical and subtropical Indo-Pacific water masses, and P. lucingens, new species,a species distributed in the subtropical and tropical Pacific and South Atlantic oceans. Photostomias liemi and P. tantilluxrepresent smaller forms, with females maturing at standard lengths less than 70 mm, making these species the smallestsexually mature stomiids. Despite the analysis of some 35 morphometric and meristic characters, females of P. liemi areindistinguishable from females of P. atrox. The current study brings the total number of valid species of Photostomias tosix. A key to these six species is provided.
THE stomiiform genus Photostomias, a member of themost derived stomiid subfamily Malacosteinae (Fink,1985), is characterized by lacking skin between the
mandibular rami, no hyoid barbel, and pelvic fins absentafter transformation (Kenaley and Hartel, 2005). Photosto-mias was originally described by Collett (1889) to containPhotostomias guernei on the basis of a single specimen caughtoff the Azores. Species of Photostomias occur at mesopelagicdepths of tropical to temperate oceans almost worldwide(Goodyear, 1990; Aizawa, 2000; Kenaley and Hartel, 2005).Photostomias has been placed in the Malacosteidae (Morrow,1964; Harold, 2003) or in the expanded Stomiidae (Fink,1985), and subsequently in the subfamily Malacosteinae(Eschmeyer, 1998; Nelson, 2006). The genus remainedmonotypic until Alcock (1899a) placed Thaumastomias atroxAlcock 1890 in synonymy of Photostomias. UltimostomiasBeebe 1933 has also been placed in synonymy of Photostomias(Fink, 1985; Harold, 2003). In a revision of the Atlanticspecies of Photostomias, Kenaley and Hartel (2005) placed P.mirabilis Beebe 1933 in synonymy of P. guernei, described P.goodyeari, and redescribed P. atrox. Hence, three species ofPhotostomias are currently recognized: P. guernei, P. atrox, andP. goodyeari. Each of these species is diagnosed by acombination of the number of basibranchial tooth patches,male and female postorbital photophore (PO) size, anddorsal- and anal-fin ray counts. Although Kenaley and Hartel(2005) limited the scope of their revision to Atlantic species,they acknowledged the existence of several undescribedspecies in the Indian and Pacific oceans. This observationcorroborated the proposal of Clarke (1974, 1982, 1983) thatthere were two undescribed species of Photostomias in thecentral North Pacific distinguishable by body size.
As with other stomiid genera, species of Photostomiasexhibit considerable sexual dimorphism in PO size (Clarke,1983; Kenaley and Hartel, 2005; Herring, 2007; Kenaley,2007). Additional sexually dimorphic characters include thepresence of an accessory orbital (AO) photophore in malesand females attaining a greater maximum size (Kenaley andHartel, 2005). Kenaley and Hartel (2005) diagnosed eachspecies based largely on characters that are not sexuallydimorphic. On the basis of an examination of 248specimens, three new species are described below, twoendemic to Indo-Pacific basins. Males of Indo-Pacific species
of Photostomias are clearly diagnosed on the basis of PO andAO size. Size-at-maturity proves important in diagnosingfemales; however, no other character or complex ofcharacters was found that distinguishes all female Indo-Pacific species of Photostomias. A comparison of morpho-metric and meristic data of these new species and thosespecies reviewed by Kenaley and Hartel (2005) reveals thatmaterial representing one of these new species also occurs inthe subtropical South Atlantic and that this new species wasidentified as P. atrox in their review. A key to all knownspecies of Photostomias is provided.
MATERIALS AND METHODS
All specimen lengths are given as standard length (SL) unlessotherwise noted. Counts and measurements were madeaccording to Hubbs and Lagler (1958), with exceptionsoutlined by Kenaley and Hartel (2005) and by thosedescribed herein. Lateral and ventral photophore terminol-ogy follows Gibbs et al. (1983). Cephalic photophoreterminology follows Fink (1985) and Kenaley and Hartel(2005). Accessory orbital phototophore (AO) length wasmeasured as the maximum dimension of the exposed organ;postorbital organ (PO) length was measured as the maxi-mum dimension of the bulbous organ restricted to the organitself, excluding the surrounding black tissue.
Upper jaw length (UJL) was measured from the anterior-most tip of the premaxilla to the posterior point of themaxilla. Head length (HL) was measured from the anterior-most tip of the premaxilla to the anterodorsal junction ofthe opercular flap and the head. Eye width was measuredfrom the anterior margin to the posterior margin of theopening in the skin that surrounds the eye. Head width(HW) was measured as the lateral distance betweensphenotic processes. The two anteriormost dorsal- andanal-fin rays are grouped closely together and countedseparately. In all cases where sex is given, sex wasdetermined by the condition of the AO (whether exposedor subcutaneous), and then confirmed by gross microscop-ical examination of the gonads. Sex is rarely reported forspecimens smaller than 60 mm as these specimens couldnot be sexed reliably. Ovum diameter is reported as theaverage diameter of five ova measured within the anterior
1 School of Aquatic and Fishery Sciences, College of Ocean and Fishery Sciences, University of Washington, Box 355020, Seattle, Washington98195; E-mail: [email protected].
Submitted: 4 October 2007. Accepted: 2 October 2008. Associate Editor: D. Buth.F 2009 by the American Society of Ichthyologists and Herpetologists DOI: 10.1643/CI-07-224
Copeia 2009, No. 1, 175–189
third of the ovary. Female maturity was determinedaccording to Clarke’s (1983) method for mesopelagic fishes,which included species of Photostomias, whereby a femalewith at least some yolk deposited in the ovum and averageovum size greater than 0.2 mm was considered maturing.
The few morphometric and meristic character values of theIndo-Pacific species of Photostomias that differ from the genericdescription of Kenaley and Hartel (2005) do not differ so muchas to warrant a redescription of the genus. Character values ofthe holotype, or in the case of P. atrox, the neotype, arereported in parentheses after the range in the speciesdescriptions. Morphometric and meristic data are furthersummarized in Tables 1 and 2. Many of the measurementsare affected by the physical condition of the specimen and thedegree to which the specimen was manipulated whilemeasuring. To minimize imprecision, diagnostic morphomet-ric characters are reported in percent of upper jaw length, amore completely ossified, less easily damaged structure. Posthoc analyses of covariance (ANCOVAs) and nonparametricMann-Whitney U-tests (MWU) were performed to evaluatesignificant differences in morphometric and meristic charac-ters, respectively, with a Sidak correction for multiple tests foran experiment-wide a of P 5 0.05. Tests for significantdifferences in allometric growth were performed with AN-COVA tests for homogeneity of regression. Values for n in allanalyses are those given in Tables 1 and 2. Results of individualpairwise statistical tests are not repeated under speciescomparisons where that value was previously reported.
Material was captured with a several midwater trawlsincluding a 10-m2 MOCNESS (MOC10), 20-m2 (MOC20), 3-m (10-ft) Isaacs-Kidd Midwater Trawl (IKMT), or a 10-m2
Rectangular Midwater Trawl (RMT). Where specific capturedepth was not available, meters of wire out (mwo) are given.Institutional abbreviations are as listed at http://www.asih.org/codons.pdf.
RESULTS
With the exception of minor deviations in meristic andmorphometric values, all specimens examined in this studypossess characters described for Photostomias by Kenaley andHartel (2005). Despite some statistical differences, species ofPhotostomias vary little in most meristic and morphometricfeatures, the only discrete characters being those diagnosticcharacters associated with the male AO and PO, number ofbasibranchial tooth patches, and dorsal- and anal-fin rays.Based on these characters, four Indo-Pacific species ofPhotostomias are described below: P. atrox and three newspecies, P. tantillux, P. liemi, and P. lucingens. No uniquecombination of characters was recovered that distinguishesfemales of P. atrox and P. liemi.
Photostomias tantillux, new speciesFigures 1A, 2A, 3–6; Tables 1, 2
Photostomias guernei.—Clarke, 1974:346, table 1 (in part,vertical distribution, occurrence off Hawaii, size atmaturity, size distributions, spawning seasonality).
Photostomias sp. 1.—Clarke, 1982:298, table 6 (prey choice,size at maturity, occurrence off Hawaii); Clarke, 1983:204,table 1 (sex ratio, size at maturity, sexual dimorphism).
Holotype.—SIO 73-171, male, 90.3 mm, eastern tropicalPacific, 0u6.89N, 155u18.79W, R/V Melville, IKMT, approxi-mately 0–1058 m, 17 July 1972.
Paratypes.—SIO 68-533, female, 64.7 mm, 4u529S,167u079W, 0–2550 mwo, 10 August 1968; SIO 68-535, male,76.4 mm, 4u599N, 164u149W, 0–2550 mwo, 13 August 1968;SIO 73-164, 2 females, 67.0–85.0 mm, 0u099N, 155u009W, 0–3000 mwo, 14 July 1972; SIO 73-165, male, 77.3 mm,0u119S, 155u509W, 0–3000 mwo, 15 July 1972; SIO 73-171, 2females, 70.8–81.2 mm, 0u079N, 155u199W, 0–1058 m, 17July 1972; USNM 219001, male, 63.6 mm, 22uN, 158uW,120–120 m, 12 November 1969; USNM 219039, female,80.1 mm, 2u039S, 150u599W, 0–55 m, 19 March 1970; USNM219047, 3 females, 77.3–85.4 mm, male, 73.9 mm, 4u079N,160u129W, 0–780 m, 22 August 1971.
Diagnosis.—Photostomias tantillux differs from all otherspecies of Photostomias in having the following combinationof characters: PO small in males greater than 60 mm, 12.1–20.0% UJL (versus PO moderate to large, 21.0–46.6% UJL, inP. atrox, P. liemi, and P. lucingens; Fig. 3; Kenaley and Hartel,2005:fig. 3, table 1); female PO small, 7.9–10.8% UJL (versusmoderate to large, 9.4–18.9% UJL, in all other species ofPhotostomias except P. guernei; Fig. 3, Table 1; Kenaley andHartel, 2005:table 1); AO small to moderate in males greaterthan 60 mm, 2.1–7.4% UJL (versus small, 2.4–4.7% UJL, in P.lucingens; Fig. 4, Table 1); females maturing (ova . 0.2 mm)at approximately 70 mm (versus 100 mm in P. atrox and P.liemi; Fig 4); three tooth patches positioned at posterior endof the first, second, and third basibranchials (versus twobasibrancial tooth patches in P. guernei); sum of dorsal- andanal-fin rays 48–52, rarely 53 (versus 57–63, rarely 56, in P.goodyeari; Table 2; Kenaley and Hartel, 2005:table 2).
Description.—Body elongate, cleithrum depth 7.5–11.3% SL(9.3%), tapering slightly to anal-fin origin, 4.6–7.1% SL(6.0%), and more abruptly toward shallow peduncle pedun-cle, 1.5–2.3% SL (1.7%). Soft, corrugated keel along ventralmidline from last IP photophore to anus. Jaws enormous,extending far posterior to posterior margin of fleshy orbit;lower jaw length 14.5–20.5% SL (16.8%), upper jaw 14.5–20.3% SL (16.8%). Skin between dentaries absent, protractorhyoideus exposed. Tip of basihyal with a white, fleshy,nautilus-shaped tab. Eye moderately large, eye width 2.2–4.6% SL (4.6%); a ring of minute photophores surroundingpupil inside of fleshy orbit. Snout blunt and short 2.5–8.2%
SL (3.3%); skin between anterodorsal process of premaxillaand anterior margin of fleshy orbit often with a depressionaccommodating second anteriormost dentary tooth whenjaws are closed; concentrated patches of luminescent tissueoften present directly anterior to orbit. Nostril facingforward on snout; a round anteroventral opening aboutone-third width of ovular upper dorsolateral opening.Opercular flap long and sloping posteroventrally to poste-rior articulation of jaws, inserting dorsal to posterior marginof fleshy orbit; a single photophore present at midpoint ofposterior margin. Branchiostegal rays 11–14 (13), a singlephotophore embedded in lateral face of membrane betweeneach exposed ray; posteriormost rays medial to inter- andsubopercle without inter-ray photophore; two anteriormostrays often with two minute inter-ray photophores.
Three cephalic photophores near orbit: AO, SO, and PO(Fig. 1A). AO sexually dimorphic, obvious in males, smallerand subcutaneous in females; male AO small to large inspecimens greater than 60 mm 2.1–7.4% UJL (7.3%). SOminute, round and situated on midventral margin of fleshyorbit in an elongate pocket with both a lateral and larger
176 Copeia 2009, No. 1
Tab
le1.
Mo
rph
om
etr
icC
har
act
er
Valu
es
ofth
eFo
ur
Kn
ow
nIn
do
-Pac
ific
Sp
eci
es
ofPh
oto
stom
ias.
Ab
bre
viatio
ns
are
as
follo
w:LD
T,lo
ngest
den
tary
too
th;LP
T,lo
ngest
pre
max
illary
too
th;U
JL,u
pp
er
jaw
len
gth
;A
O,acc
ess
ory
orb
ital
pho
top
ho
re;
PO
,p
ost
orb
ital
ph
oto
ph
ore
.
P.ta
ntillu
xP.lie
mi(m
ale
s)P.lu
cin
gen
sP.a
trox
(male
s)P.a
trox/
liem
i(f
em
ale
s)
ran
ge
(mean
6SD
)n
ran
ge
(mean
6SD
)n
ran
ge
(mean
6SD
)n
ran
ge
(mean
6SD
)n
ran
ge
(mean
6SD
)n
SL5
0.2
–1
00
.7(7
4.7
61
1.0
)5
05
9.6
–1
42
.6(9
8.4
61
6.0
)2
35
3.8
–1
09
.0(8
0.7
61
5.5
)3
52
2–
15
4(9
4.1
63
0.5
)1
10
50
.2–
15
3.4
(10
1.9
62
8.3
)3
0Le
ngt
h%
SLH
ead
6.6
–9
.8(7
.96
0.7
)3
37
.6–
8.9
(8.3
60
.4)
12
7.1
–8
.9(8
.16
0.5
)1
86
.0–
9.2
(7.4
60
.8)
40
6.3
–8
.6(6
.66
1.4
)1
2Sn
out
2.5
–8
.2(3
.46
0.9
)3
13
.0–
3.7
(3.3
60
.2)
11
2.7
–3
.9(3
.36
0.4
)1
82
.5–
3.9
(3.2
60
.4)
40
2.7
–3
.6(3
.26
0.3
)1
0U
pper
Jaw
14
.5–
20
.3(1
7.8
61
.0)
43
16
.2–
19
.6(1
7.9
61
.0)
21
16
.4–
20
.4(1
8.0
61
.1)
30
14
.6–
22
.5(1
7.4
61
.2)
80
15
.9–
20
.2(1
7.7
61
.0)
27
Low
erja
w1
4.5
–2
0.5
(17
.86
1.1
)2
91
6.1
–1
9.8
(18
.26
1.1
)1
41
6.8
–2
0.8
(18
.66
1.1
)1
41
6.3
–2
0.7
(18
.56
1.2
)4
21
6.8
–2
0.0
(18
.26
0.9
)1
6LD
T2
.9–
4.9
(3.6
60
.5)
25
2.7
–5
.9(3
.66
0.9
)1
12
.7–
4.2
(3.5
60
.5)
21
1.8
–4
.8(3
.36
0.6
)5
63
.2–
5.0
(3.9
60
.5)
13
LPT
1.1
–3
.5(1
.86
0.4
)2
91
.0–
2.0
(1.5
60
.3)
81
.2–
2.3
(1.7
60
.2)
23
0.9
–2
.5(1
.66
0.3
)6
41
.2–
2.4
(1.8
60
.3)
13
Pre
dors
al8
1.4
–8
6.1
(83
.56
1.2
)3
17
8.5
–8
5.6
(81
.36
2.0
)1
28
0.8
–8
6.5
(83
.26
1.4
)2
27
2.0
–8
6.3
(81
.96
2.4
)5
57
9.6
–8
3.8
(81
.86
1.4
)1
3Pre
anal
77
.6–
85
.3(8
1.4
61
.5)
31
78
.1–
84
.3(8
0.0
62
.0)
12
78
.8–
83
.4(8
1.0
61
.3)
22
71
.1–
83
.5(8
0.1
62
.1)
54
78
.4–
82
.2(8
0.3
61
.2)
13
Dors
al-fin
bas
e1
2.4
–1
6.2
(14
.46
0.7
)3
31
2.9
–1
7.2
(15
.56
1.3
)1
21
2.7
–1
7.4
(14
.36
1.0
)2
41
2.7
–1
6.8
(14
.66
0.9
)5
61
4.5
–1
6.8
(15
.76
0.8
)1
2Anal
-fin
bas
e1
2.9
–1
7.7
(16
.26
0.9
)3
41
5.2
–1
8.6
(17
.06
1.1
)1
21
4.5
–1
8.0
(16
.36
1.0
)2
41
4.9
–1
8.1
(16
.36
0.7
)5
61
6.1
–1
7.9
(17
.26
0.6
)1
2Pel
vic
fin3
2.2
–5
4.1
(40
.16
8.3
)6
40
.3–
54
.1(4
4.6
66
.4)
44
4.5
–5
1.0
(48
.56
3.5
)3
37
.6–
51
.8(4
5.0
64
.2)
16
42
.3–
49
.3(4
6.0
62
.6)
7Pre
-pel
vic
42
.4–
47
.5(4
5.0
62
.2)
75
4.1
13
9.8
–4
8.0
(43
.36
4.2
)3
41
.3–
48
.5(4
5.3
63
.6)
44
1.5
–4
5.2
(42
.96
1.6
)4
Wid
th%
SLH
ead
4.9
–6
.6(5
.76
0.4
)4
43
.7–
6.3
(5.7
60
.6)
18
4.6
–6
.5(5
.76
0.5
)1
94
.4–
6.9
(5.6
60
.6)
42
4.9
–6
.6(5
.66
0.5
)1
9Ey
e2
.2–
4.6
(3.3
60
.4)
35
3.2
–5
.7(4
.16
0.6
)1
42
.2–
4.4
(3.4
60
.5)
10
2.6
–5
.3(3
.66
1.0
)7
62
.4–
4.4
(3.4
.46
0.5
)1
6B
ody
dep
th%
SLC
leith
rum
7.5
–1
1.3
(9.4
61
.0)
31
8.1
–1
1.4
(9.2
61
.0)
12
7.4
–1
0.6
(9.4
60
.8)
20
7.1
–1
2.2
(9.4
61
.1)
39
7.9
–1
2.3
(10
.16
1.5
)1
2Anal
-fin
orig
in4
.6–
7.1
(5.7
60
.6)
34
5.2
–6
.6(5
.96
0.5
)1
24
.7–
6.7
(5.9
60
.5)
20
4.6
–7
.3(5
.96
0.6
)3
94
.8–
7.7
(6.1
60
.8)
12
Ped
uncl
e1
.5–
2.3
(1.9
60
.2)
34
1.6
–2
.1(1
.96
0.2
)1
21
.8–
2.3
(2.0
60
.1)
20
1.5
–2
.3(1
.86
0.2
)3
91
.4–
2.1
(1.8
60
.2)
12
Wid
th%
UJL
AO
2.1
–7
.4(4
.56
0.2
)2
44
.9–
8.3
(6.6
60
.9)
20
2.4
–4
.7(3
.46
0.8
)1
35
.3–
9.6
(6.6
61
.2)
32
——
Mal
ePO
12
.1–
20
.0(1
6.2
64
.1)
24
21
.0–
25
.3(2
3.1
61
.5)
20
26
.8–
39
.9(3
1.7
63
.7)
12
26
.8–
46
.6(3
3.8
64
.7)
31
——
Fem
ale
PO
7.9
–1
0.8
(9.2
60
.9)
18
——
10
.3–
15
.0(1
2.2
61
.5)
10
——
10
.5–
18
.9(1
3.9
62
.1)
27
Kenaley—Indo-Pacific species of Photostomias 177
dorsomedial opening. PO sexually dimorphic, small inmales, minute in females, a deep, right-triangle shapedorgan pointing posteriorly; in specimens greater than60 mm, male PO 12.1–20.0% UJL (14.4%), female PO 7.9–10.8% UJL (Table 1); placed posterior to fleshy orbit withlower edge aligned with ventral margin of fleshy orbit.
Dentary and premaxillary teeth fixed, not depressible, andcurved posterodorsally. Dentary teeth numerous 8–34 (15),becoming fewer with increase in SL; variable in size, mostanterior pair slender, barbed, and enormous 2.9–4.9% SL(3.0%); posterior dentary teeth unbarbed and smaller.Premaxillary teeth small to moderate, less numerous (5–11) and variable in size; second anteriormost tooth, or that
positioned under fleshy orbit, longest and barbed, 1.1–3.5%
UJL (1.1%). Maxillary teeth small, directed posteriorly, andnumerous 13–32 (16), increasing in number with increase inSL; anterior maxillary teeth smaller, posterior teeth larger.Palatines bearing 2–11 (6) posteromedially directed teeth,arranged serially in anteroposterior row. Basibranchialsbearing three tooth patches each with 2–5 dorsoposterallydirected teeth; a tooth patch positioned at posterior end ofbasibranchials of first, second, and third arches. Pharyngo-branchials bearing two tooth patches with slender, curved,ventroposteriorly directed teeth; anterior patch with 3–7teeth, posterior patch with 6–14 teeth. Gill teeth 6–12 (6) aspatches of small tack-like teeth or as a single tooth.
Table 2. Selected Meristic Character Values of the Four Known Indo-Pacific Species of Photostomias. Photophore terminologies follow Gibbs et al.(1983). Asterisks denote counts of holotypes or neotype of P. atrox.
BPphotophores 9 10 11 12 13 14 Sum PV photophores 13 14 15 16 17 18 Sum
P. tantillux 1 3 12 19* — 1 36 P. tantillux — 1 9 16 5 1* 32P. liemi — 2 7* 5 — — 14 P. liemi — 3 8 6* — — 17P. lucingens — 5* 14 6 1 — 26 P. lucingens 3 4 8 12* — — 27P. atrox 2 21 42* 8 1 — 74 P. atrox 1 17 43 10* 1 — 72P. atrox/liemi
(females)1 2 8 2 1 — 14 P. atrox/liemi
(females)— 6 9 1 — — 16
VAV photophores 19 20 21 22 23 24 25 26 Sum OV photophores 13 14 15 16 17 18 Sum
P. tantillux — 2* 3 13 14 — 1 — 33 P. tantillux 1 1 3 17 7 4* 33P. liemi 1 — 1 9* 5 1 — — 17 P. liemi — 4 14 12* 1 — 31P. lucingens — — 2 7 8* 8 1 1 27 P. lucingens 1 7 14 12 1* — 35P. atrox — — 14 24 25* 8 1 — 72 P. atrox — 11 39 21* 1 — 72P. atrox/liemi (females) — — — 7 7 1 — 1 16 P. atrox/liemi
(females)— 4 9 3 — — 16
VALphotophores 19 20 21 22 23 24 25 Sum AC photophores 11 12 13 14 15 Sum
P. tantillux 1* 8 11 7 4 1 — 32 P. tantillux 1 5 19* 7 — 32P. liemi 1 2 7 5* 2 — — 17 P. liemi — 3 12* 2 — 17P. lucingens — 2 12* 7 4 1 1 27 P. lucingens — 4* 22 — 1 27P. atrox 2 10 28* 23 6 — — 69 P. atrox — 7 39 23* 1 70P. atrox/liemi
(females)— 2 4 6 3 — — 15 P. atrox/liemi
(females)— 1 11 3 1 16
Dorsal-finrays 21 22 23 24 25 26 Sum Anal-fin rays 25 26 27 28 29 30 Sum
P. tantillux — 16* 20 8 1 1 46 P. tantillux — 8 20* 13 4 1 46P. liemi — 2 4 8* 5 3 22 P. liemi — 2 5 10* 5 — 22P. lucingens 1 4 13* 5 7 1 31 P. lucingens — 3 6 13 6* 3 31P. atrox — 1 17 48* 39 3 108 P. atrox — 6 38 39* 21 3 107P. atrox/liemi
(females)— 4 6 5 5 3 23 P. atrox/liemi
(females)1 4 8 8 3 — 24
Sum of anal- anddorsal-fin rays 47 48 49 50 51 52 53 54 55 56 Sum
P. tantillux — 4 10* 13 12 5 — — — 1 45P. liemi — — 2 3 4 4* 6 — 3 — 22P. lucingens 1 1 2 4 10 5* 2 3 2 1 31P. atrox — — 5 11 25 27* 18 17 4 — 107P. atrox/liemi (females) 1 — 5 3 1 7 3 3 — — 23
178 Copeia 2009, No. 1
Pectoral fin absent in transformed specimens. Pelvic finsextremely elongate, 32.2–54.1% SL (damaged), with 6 rays;proximal ray flattened and separate from remaining fiverays; placed approximately at mid-body; prepelvic length42.4–47.5% SL (44.6%). Dorsal and anal fins placed far backon body and nearly opposite, predorsal length 81.4–86.1%
SL (82.8%), preanal length 77.6–85.3% SL (77.6%); skinextending over proximal third of fin bases. Dorsal-fin rays22–26 (22), rarely 25 or 26; anal-fin rays 26–29 (27), rarely30. Anteriormost rays of dorsal and anal fins small andtightly spaced, often obscured by skin. Caudal fin small andforked, lobes falcate, ventral lobe considerably longer thandorsal lobe.
IP 7, two posteriormost photophores separated by a spaceapproximately half of that between other photophores inthe series; PV 14–18 (18), separated from IP by a space equalto width of approximately 5 photophores; VAV 20–23 (20),rarely 25, separated from PV by a space equal to width ofapproximately 5 photophores, last 1–3 photophores overanal-fin base. OV 13–18 (18), anterior 4 or 5 photophoresarched anteroventrally, ventralmost (first) photophore be-coming obscured in larger specimens; VAL 19–24 (19),separated from OV by a space equal to width of 4–6photophores; AC 11–14 (13), elevated at level of VAL andseparated from them by a space equal to width ofapproximately 6 photophores, first AC directly over lastVAV.
Skin thin, scaleless; vertical rows of minute photophoresarranged along lateral aspect of body beginning directlyposterior to opercular flap, each row corresponding to bodysegment. Minute masses of luminescent tissue scatter overentire body. Color in alcohol black, fading to dark brownafter lengthy preservation. Size small, to 101 mm; femalesmaturing at approximately 70 mm (Fig. 5), males at approx-imately 60 mm.
Distribution.—Tropical and subtropical Pacific Ocean, from33uN off Skikoko, Japan, to 31uS in the eastern South Pacific(Fig. 6).
Comparison.—The small relative size of the PO in both malesand females (Fig. 3) distinguishes P. tantillux from all otherIndo-Pacific species of Photostomias. Smaller female speci-mens may be confused with P. atrox and P. liemi; however, P.tantillux matures at a much smaller size (approximately70 mm versus approximately 100 mm in P. atrox and P.liemi; Fig. 5). The following diagnostic characters of P.tantillux were found to differ significantly from other Indo-Pacific species of Photostomias: as percent of UJL, male POsmaller than those of P. liemi and P. lucingens (both P ,
0.001), and smaller and slower in allometric growth thanthat of P. atrox (P , 0.001); male AO larger and growingfaster as percent of UJL than that of P. lucingens (P 5 0.018);female PO smaller as percent of UJL than those of P. atrox/P.liemi and P. lucingens (both P , 0.001). In addition, thefollowing characters differ significantly from other Indo-Pacific species of Photostomias: head length smaller as apercent of SL than that of P. liemi (P 5 0.004); head widthsmaller as a percent of SL than that of P. liemi (P , 0.001);prepelvic length greater as a percent of SL than that of P.atrox (P 5 0.035); dorsal-fin rays fewer than those of P. atroxand P. liemi (both P , 0.001); anal-fin rays fewer than thoseof P. lucingens (P 5 0.040); number of BP photophoresgreater than those of P. atrox (P , 0.001); number of PVphotophores greater than those of P. atrox, P. liemi, and P.lucingens (P , 0.001, P 5 0.028, and P 5 0.033, respectively);OV greater than those of P. atrox and P. liemi (P , 0.001 andP 5 0.032, respectively). The following characters differ inallometric growth: number of maxillary teeth accumulatingfaster than those of P. atrox and P. liemi (P , 0.001 and P 5
0.041); growth of anal-fin base faster than that of P. lucingens(P 5 0.041).
Etymology.—The name tantillux is derived from a combina-tion of the Latin tantillus, meaning ‘‘so little’’ or ‘‘so small,’’and lux, meaning ‘‘light,’’ in allusion to the small size of thelight-producing PO of this species.
Photostomias liemi, new speciesFigures 1B, 2B, 3–5, 7; Tables 1, 2
Holotype.—MCZ 49151, male, 95.2 mm, central NorthPacific, Off Kona, Hawaii, 0–762 m, February 1973, OtisBarton.
Paratypes.—AMS I.19739-034, male, 99.4 mm, 7u099S,148u529E, 5-V11/69, 0–137 m, 7 November 1969; AMSI.36467-019, male, 142.6 mm, 17u379N, 122u439E, 28 Sep-tember 1995; SIO 68-472, male, 116.2 mm, 19u129N,166u509N, 0–2100 m, 12–13 September 1968; SIO 71-307,male, 96.3 mm, 27u269N, 155u259W, 0–3000 mwo, 1October 1971; SIO 72-22, male, 118.2 mm, 27u259N,155u239W, 0–1500 mwo, 28 September 1971; SIO 75-324,male, 95.4 mm, 9u189N, 122u009W, 0–200 m, 3 February1973; SIO 88-155, male, 75.3 mm, 19u269N, 169u419W, 6March 1987; USNM 258713, male, 100.4 mm, 21u259N,158u259W, 0–195 m, 28 February 1973; USNM 258719,male, 87.9 mm, 21u259N, 158u209W, 0–800 m, 2 March1971; USNM 292394, male, 95.4 mm, 18u569S, 150u089E, 0–360 m, 19–20 June 1981; USNM 382262, male, 109.2 mm,21u239N, 158u189W, 1500–4000 m, 28 February 1972; USNM382263, male, 97.1 mm, 21u229N, 158u199W, 575–655 m, 26March 1972.
Fig. 1. Left lateral view of heads of Indo-Pacific species of Photo-stomias: (A) P. tantillux new species, holotype, SIO 73-171, male,90.3 mm SL; (B) P. liemi new species, holotype, MCZ 49151, male,95.2 mm SL; (C) P. lucingens new species, holotype, USNM 219291,male, 78.2 mm SL; (D) P. atrox, neotype, MCZ 151289, male,92.0 mm SL.
Kenaley—Indo-Pacific species of Photostomias 179
Fig. 2. Left lateral view of Indo-Pacific species of Photostomias: (A) P. tantillux new species, holotype, SIO 73-171, male, 90.3 mm SL; (B) P. lieminew species, holotype, MCZ 49151, male, 95.2 mm SL; (C) P. lucingens new species, holotype, USNM 219291, male, 78.2 mm SL; (D) P. atrox,neotype, MCZ 151289, male, 92.0 mm SL.
180 Copeia 2009, No. 1
Diagnosis.—Males of Photostomias liemi differs from all otherspecies of Photostomias, and females differ from all otherspecies of Photostomias, with the exception of females of P.atrox, by having the following combination of characters:
PO of moderate size, 21.0–25.3% UJL, in males greater than60 mm (versus PO small, 12.1–20.0% UJL, in P. tantillux, andlarge, 26.8–46.6% UJL, in P. atrox and P. lucingens n. sp; Fig. 3,Table 1); AO of moderate size, 4.9–8.3% UJL, in males greaterthan 60 mm (versus AO small, 2.4–4.7% UJL, in P. lucingens;Fig. 4, Table 1); three tooth patches positioned at posteriorend of the first, second, and third basibranchials (versus twobasibrancial tooth patches in P. guernei); sum of dorsal- andanal-fin rays 49–53, rarely 55 (versus 57–63, rarely 56, in P.goodyeari; Table 2; Kenaley and Hartel, 2005:table 2); femalesmaturing at approximately 100 mm (versus less than 70 mmin P. tantillux and P. lucingens; Fig. 5). Females of P. liemi areindistinguishable from females of P. atrox.
Description of males.—Body elongate, cleithrum depth 8.1–11.4% SL (8.7%), tapering slightly to anal-fin origin, 5.2–6.6% SL (5.2%), and more abruptly toward shallow caudalpeduncle, 1.6–2.1% SL (1.9%). Soft, corrugated keel alongventral midline from last IP photophore to anus. Jawsenormous, extending far posterior to posterior margin offleshy orbit; lower jaw length 16.1–19.8% SL (17.8%), upperjaw 16.2–19.6% SL (16.8%). Skin between dentaries absent,protractor hyoideus exposed. Tip of basihyal with a white,fleshy, nautilus-shaped tab. Eye large, eye width 3.2–5.7% SL(4.3%); a ring of minute photophores surrounding pupilinside of fleshy orbit. Snout blunt, 3.0–3.7% SL (3.3%); nodepression to accommodate dentary teeth in skin betweenanterodorsal process of premaxilla and anterior margin offleshy orbit; patches of luminescent tissue usually absentanterior to orbit, if present, only as diffuse patches. Nostrilfacing forward on snout; a round anteroventral openingabout one-third width of ovular upper dorsolateral opening.Opercular flap long and sloping posteroventrally to poste-rior articulation of jaws, inserting dorsal to posterior marginof fleshy orbit; a single photophore present at midpoint ofposterior margin. Branchiostegal rays 11–13 (12), a singlephotophore embedded in lateral face of membrane betweeneach exposed ray; posteriormost rays medial to inter- andsubopercle without inter-ray photophore; two anteriormostrays often with two minute inter-ray photophores.
Fig. 4. Accessory orbital photophore (AO) size versus upper jaw length(UJL) of male Indo-Pacific species of Photostomias.
Fig. 3. Postorbital photophore (PO) size versus upper jaw length (UJL)of Indo-Pacific species of Photostomias.
Fig. 5. Ovum size versus standard length (SL) of female Indo-Pacificspecies of Photostomias. Ovum values of zero reflect specimens with noapparent ovarian development.
Kenaley—Indo-Pacific species of Photostomias 181
Three cephalic photophores near orbit: AO, SO, and PO(Fig. 1B). AO moderately large in specimens greater than60 mm, 4.9–8.3% UJL (7.1). SO minute, round and situatedon midventral margin of fleshy orbit in an elongate pocketwith both a lateral and larger dorsomedial opening. PO anelongate triangle pointing posteriorly; 21.0–25.3% UJL(21.6%) in specimens greater than 60 mm (Figs. 1B, 3;Table 1); placed posterior to fleshy orbit with lower edgealigned with ventral margin of fleshy orbit.
All dentary and premaxillary teeth fixed, not depressible,and curved posterodorsally. Dentary teeth numerous 13–29(27), becoming fewer with increase in SL; variable in size,most anterior pair slender, barbed, and enormous, longestdentary tooth 2.7–5.9% SL (3.7%); posterior dentary teethunbarbed and smaller. Premaxillary teeth small to moderate,less numerous (7–12) and variable in size; second anterior-most tooth, or that positioned under fleshy orbit, longest,1.0–2.0% SL (1.6%), and barbed. Maxillary teeth small,directed posteriorly, and numerous 18–33 (21), increasing innumber with increase in SL; anterior maxillary teeth smaller,
posterior teeth larger. Palatines bearing 4–8 (7) poster-omedially directed teeth, arranged serially in anteroposteri-or row. Basibranchials bearing three tooth patches each with2–4 dorsoposterally directed teeth; a tooth patch positionedat posterior margin of basibranchials of first, second, andthird arches. Pharyngobranchials bearing two tooth patcheswith slender, curved, ventroposteriorly directed teeth;anterior patch with 2–7 (7) teeth, posterior patch with 7–12 (10) teeth. Gill teeth 5–11 (11) as patches of small tack-like teeth or as a single tooth.
Pectoral fin absent in transformed specimens. Pelvic finsextremely elongate, 40.3–54.1% SL (40.3%), with 6 rays;proximal ray flattened and separate from remaining fiverays; placed approximately at mid-body; prepelvic length54.1 (54.1%). Dorsal and anal fins placed far back on bodyand nearly opposite, predorsal length 78.5–85.6% SL(80.3%), preanal length 78.1–84.3% SL (80.2%); skinextending over proximal third of fin bases. Dorsal-fin rays22–26 (24), anal-fin rays 26–29 (28). Anteriormost rays ofdorsal and anal fins small and tightly spaced, often obscured
Fig. 6. Distribution of Photostomias tantillux and P. lucingens. Symbols may represent more than one record.
Fig. 7. Distribution of Photostomias atrox and P. liemi; symbols corresponding to P. atrox/P. liemi represent captures of females that wereambiguously identified as either of these species. Symbols may represent more than one record.
182 Copeia 2009, No. 1
by skin. Caudal fin small and forked, lobes falcate, ventrallobe longer than dorsal lobe.
IP 7, two posteriormost photophores separated by a spaceapproximately half of that between other photophores inthe series; PV 14–16 (16), separated from IP by a space equalto width of approximately 5 or 6 photophores; VAV 21–24(22), rarely 19, separated from PV by a space equal to widthof approximately 5 or 6 photophores, last 2–3 photophoresover anal-fin base. OV 14–17 (16), anterior 4 or 5photophores arched anteroventrally; VAL 19–23 (22), sepa-rated from OV by a space equal to width of 5 or 6photophores. A single small photophore placed approxi-mately at mid-point of opercular flap on margin ofoperculum; AC 12–14 (13), elevated at level of VAL andseparated from them by a space equal to width ofapproximately 6 photophores, first AC directly over lastVAV.
Skin thin, scaleless; vertical rows of minute photophoresarranged along lateral aspect of body beginning directlyposterior to opercular flap, each row corresponding to abody segment. Minute masses of luminescent tissue scat-tered over entire body. Color in alcohol black, fading to darkbrown after lengthy preservation. Size moderately large, to143 mm; females maturing at approximately 100 mm,males at approximately 85 mm.
Distribution.—Males captured off the Indo-Malaysian, Japa-nese, Philippine, and Hawaiian archipelagos; scatteredrecords from the tropical Pacific; one record from theeastern Indian Ocean off Java, Indonesia (Fig. 7).
Comparison.—The moderate size of the male PO (Fig. 3)distinguishes P. liemi from all other Indo-Pacific species ofPhotostomias. No morphological characters were recoveredthat serve to distinguish females of P. liemi from females ofP. atrox. However, as a group, females of P. liemi and P. atroxdiffer from P. tantillux and P. lucingens on the basis of size atmaturity: P. liemi and P. atrox mature at approximately100 mm versus approximately 60 and 70 mm in P. lucingensand P. tantillux, respectively (Fig. 5). Females of Photostomiasatrox and P. liemi also differ from females of P. tantillux onthe basis of PO size, P. tantillux having a much smaller PO asa percent of UJL (Fig. 3). The following diagnostic charactersof P. liemi were found to differ significantly from other Indo-Pacific species of Photostomias: as percent of UJL, male POlarger than that of P. tantillux (P , 0.001) and smaller thanthat of P. lucingens and P. atrox (both P , 0.001). Male AOlarger relative to UJL than that of P. lucingens (P , 0.001). Inaddition, the following non-diagnostic characters, as de-scribed from male specimens, differ significantly from otherIndo-Pacific species of Photostomias: HL larger as a percent ofSL than those of P. atrox and P. tantillux (P , 0.001 and P 5
0.004, respectively); head width greater as a percent of SLthan those of P. lucingens and P. tantillux (P 5 0.009 and P ,
0.001, respectively); predorsal length smaller than P. lucin-gens and P. tantillux as a percent SL (P 5 0.037 and P 5
0.019); dorsal-fin rays greater than those of P. tantillux (P ,
0.001); PV photophores fewer than those of P. tantillux (P 5
0.028); number of OV photophores fewer than those of P.tantillux (P 5 0.032). In addition, the following charactersdiffer in allometric growth: growth of dorsal-fin base fasterthan that of P. lucingens; growth of anal-fin base faster thanthose of P. atrox, P. lucingens, and P. tantillux (P 5 0.027, P ,
0.001, and P 5 0.020, respectively); growth of pre-anal
length slower than that of P. atrox and P. lucingens (P 5
0.043, P , 0.001, and P 5 0.002, respectively).
Etymology.—This species is named in honor of Karel F. Liem,recognizing over three decades of curation and support ofscientists, students, and staff as Curator of Ichthyology andHenry Bryant Bigelow Professor of Ichthyology at theMuseum of Comparative Zoology, Harvard University.
Photostomias lucingens, new speciesFigures 1C, 2C, 3–6; Tables 1, 2
Photostomias atrox (non Alcock, 1890).—Kenaley and Hartel2005:258 (in part, description, occurrence in Atlantic).
Holotype.—USNM 219291, male, 78.2 mm, central NorthPacific, off Leeward Oahu, Hawaii, 21u20–309N, 158u20–309W, HIMB 70-7-17, IKMT, 0–115 m, 7–8 July 1970.
Paratypes.—MCZ 131736, female, 95.0 mm, male, 86.0 mm,5u309S, 8u379E, 95–100 m, 15 June 1971; MCZ 161573,male, 83.0 mm, 23u309S, 30u009W, 0–1155 m, 12 May 1965;SIO 63-551, male, 109.0 mm, 19u059S, 13u409W, 0–2000 m,24–25 June 1963; SIO 69-345, male, 105.9 mm, 25u489S,108u489W, 0–2000 m, 4–5 April 1969; SIO 72-23, male,65.4 mm, 27u259N, 155u239W, 0–1500 mwo, 28 September1971; SIO 72-309, male, 103.7 mm, 25u189S, 154u559W, 29–30 July 1972; SIO 75-633, 2 males, 88.5–89.0, 25u159S,155u249W, 0–1000 mwo, 3 August 1972; USNM 258675,male, 77.9 mm, 21u259N, 158u209W, 0–750 m, 17 September1971; USNM 296737, 2 females, 80.0–85.0 mm, 3 males,79.0–99.0 mm, 15u459S, 6u069W, 1800–1900 m, 5 April1971; USNM 305264, female 73.0 mm, male 105.0 mm,13u109S, 09u009W, 6 April 1971.
Diagnosis.—Photostomias lucingens differs from all otherspecies of Photostomias by the following combination ofcharacters: male PO large, 26.8–39.9% UJL, in specimensgreater than 60 mm (versus small to moderate, 7.8–28.1%
UJL, in all other species of Photostomias except P. atrox;Fig. 3, Table 1; Kenaley and Hartel, 2005:table 1); female POmoderate, 10.3–15.0% UJL, in specimens greater than60 mm (versus small, 6.1–11.1% UJL, in P. tantillux and P.goodyeari; Fig. 3, Table 1, Kenaley and Hartel, 2005:table 1);male AO small, 2.4–4.7% UJL, in specimens greater than60 mm (versus large, 4.9–9.6% UJL, in P. tantillux and P.atrox; Fig. 4, Table 1); three tooth patches positioned atposterior end of the first, second, and third basibranchials(versus two basibrancial tooth patches in P. guernei); sum ofdorsal- and anal-fin rays 49–55, rarely 47, 48, or 56 (versus57–63, rarely 56, in P. goodyeari; Table 2; Kenaley and Hartel,2005:table 2); females maturing at a small size, approxi-mately 60 mm (versus greater than 100 mm in P. atrox andP. liemi; Fig. 5).
Description.—Body elongate, cleithrum depth 7.4–10.6% SL(9.5%), tapering slightly to anal-fin origin, 4.7–6.7% SL(6.4%), and more abruptly toward shallow peduncle pedun-cle, 1.8–2.3% SL (2.0%). Soft, corrugated keel along ventralmidline from last IP photophore to anus. Jaws enormous,extending far posterior to posterior margin of fleshy orbit;lower jaw length 16.8–20.8% SL (17.9%), upper jaw 16.4–20.4% SL (17.6%). Skin between dentaries absent, protractorhyoideus exposed. Tip of basihyal with a white, fleshy,nautilus-shaped tab. Eye moderately large, eye width 2.2–
Kenaley—Indo-Pacific species of Photostomias 183
4.4% SL (4.4%); a ring of minute photophores surroundingpupil inside of fleshy orbit. Snout blunt and short 2.7–3.9%
SL (3.0%); skin between anterodorsal process of premaxillaand anterior margin of fleshy orbit often with a depressionaccommodating second anteriormost dentary tooth whenjaws are closed; concentrated patches of luminescent tissueoften present directly anterior to orbit. Nostril facingforward on snout; a round anteroventral opening aboutone-third width of ovular upper dorsolateral opening.Opercular flap long and sloping posteroventrally to poste-rior articulation of jaws, inserting dorsal to posterior marginof fleshy orbit; a single photophore present at midpoint ofposterior margin. Branchiostegal rays 11–13 (12), a singlephotophore embedded in lateral face of membrane betweeneach exposed ray; posteriormost rays medial to inter- andsubopercle without inter-ray photophore; two anteriormostrays often with two minute inter-ray photophores.
Three cephalic photophores near orbit: AO, SO, and PO(Fig. 1C). AO sexually dimorphic, obvious in males, smallerand subcutaneous in females; male AO minute in specimensgreater than 60 mm 2.4–4.7% UJL (2.5%). SO minute, roundand situated on midventral margin of fleshy orbit in anelongate pocket with both a lateral and larger dorsomedialopening. PO sexually dimorphic, enormous in males,moderately large in females, an elongate, triangle-shapedorgan pointing posteriorly; in specimens greater than60 mm, male PO 26.8–39.9% UJL (32.3%), female PO10.3–15.0% UJL; placed posterior to fleshy orbit with loweredge aligned with ventral margin of fleshy orbit.
Dentary and premaxillary teeth fixed, not depressible, andcurved posterodorsally. Dentary teeth numerous, 14–41(22), becoming fewer with increase in SL; variable in size,most anterior pair slender, barbed, and enormous, 2.7–4.2%
SL (3.2%); posterior dentary teeth unbarbed and smaller.Premaxillary teeth small to moderate, less numerous, 6–10(7), and variable in size; second anteriormost tooth, or thatpositioned under fleshy orbit, longest and barbed, 1.2–2.3%
UJL (1.2%). Maxillary teeth small, directed posteriorly, andnumerous 13–32 (16), increasing in number with increase inSL; anterior maxillary teeth smaller, posterior teeth larger.Palatines bearing 4–9 (5) posteromedially directed teeth,arranged serially in anteroposterior row. Basibranchialsbearing three tooth patches each with 2–5 dorsoposterallydirected teeth; a tooth patch positioned at posterior end ofbasibranchials of first, second, and third arches. Pharyngo-branchials bearing two tooth patches with slender, curved,ventroposteriorly directed teeth; anterior patch with 4–8teeth, posterior patch with 6–12 teeth. Gill teeth 5–12 (10) aspatches of small tack-like teeth or as a single tooth.
Pectoral fin absent in transformed specimens. Pelvic finsextremely elongate, 44.4–51.0% SL (damaged), with 6 rays;proximal ray flattened and separate from remaining fiverays; placed approximately at mid-body; prepelvic length39.8–48.0% SL (46.8%). Dorsal and anal fins placed far backon body and nearly opposite, predorsal length 80.8–86.5%
SL (82.6%), preanal length 78.8–83.4% SL (80.7%); skinextending over proximal third of fin bases. Dorsal-fin rays22–25 (23), rarely 21 or 26; anal-fin rays 26–30 (29).Anteriormost rays of dorsal and anal fins small and tightlyspaced, often obscured by skin. Caudal fin small and forked,lobes falcate, ventral lobe considerably longer than dorsallobe.
IP 7, two posteriormost photophores separated by a spaceapproximately half of that between other photophores in
the series; PV 13–16 (16), separated from IP by a space equalto width of approximately 6 photophores; VAV 21–26 (23),separated from PV by a space equal to width of approxi-mately 4 or 5 photophores, last 1–3 photophores over anal-fin base; OV 13–17 (17), anterior 4 or 5 photophores archedanteroventrally, ventralmost (first) photophore becomingobscured in larger specimens; VAL 20–25 (21), separatedfrom OV by a space equal to width of 4–6 photophores; AC12–13 (12), rarely 15; elevated at level of VAL and separatedfrom them by a space equal to width of approximately 6photophores, first AC directly over last VAV.
Skin thin, scaleless; vertical rows of minute photophoresarranged along lateral aspect of body beginning directlyposterior to opercular flap, each row corresponding to bodysegment. Minute masses of luminescent tissue scattered overentire body. Color in alcohol black, fading to dark brownafter lengthy preservation. Size small, to 106 mm; femalesmaturing at approximately 60 mm (Fig. 5), males at approx-imately 55 mm.
Distribution.—Antitropical in the Pacific, from over the LordHowe Rise to the East Pacific Rise in the South Pacific, andfrom the Philippine Archipelago to the Hawaiian Archipel-ago in the North Pacific; in the eastern South Atlantic from5uS to 23uS (Fig. 6).
Comparison.—The large size of the male PO (Fig. 3), smallsize of the male AO (Fig. 4), and small size at which femalesof this species mature (Fig. 5) distinguish Photostomiaslucingens from all other species of Photostomias. This speciesmay be confused with P. atrox; however, males of P. lucingenspossess a much smaller AO (2.4–4.7% UJL versus 5.3–8.6%
UJL in P. atrox; Fig. 4, Table 1) and females mature at amuch smaller size (approximately 60 mm versus approxi-mately 100 mm in P. atrox/P. liemi; Fig. 5). Females of P.lucingens may be confused with P. tantillux, the other smallspecies of Photostomias; however, females of P. lucingens havea larger PO (10.3–15.0% UJL versus 7.9–10.8% UJL in P.tantillux; Fig. 3, Table 1). The following diagnostic charac-ters of P. lucingens differ significantly from other Indo-Pacificspecies of Photostomias: male PO larger as a percent UJL thanthat of P. liemi (P , 0.001) and larger and growing fasterrelative to UJL than that of P. tantillux (P , 0.001); AOsmaller and growing slower relative to UJL than those of P.atrox, P. liemi, and P. tantillux (P 5 0.002, P , 0.001, P ,
0.001, respectively). The following characters also differsignificantly from other Indo-Pacific species of Photostomias:head width smaller than those of P. atrox and P. liemi aspercent SL (P 5 0.002 and P 5 0.035, respectively); predorsallength greater than that of P. liemi (P 5 0.037); number ofdorsal-fin rays fewer than those of P. atrox (P 5 0.007);number of anal-fin rays greater than those of P. tantillux (P 5
0.040), number of PV photophores fewer than those of P.tantillux (P 5 0.033). The following characters differ inallometric growth: dorsal-fin base shorter and growing moreslowly than those of P. atrox and P. liemi (P 5 0.0325 and P 5
0.005, respectively); anal-fin base growing more slowly thanthose of P. atrox, P. liemi, and P. tantillux (P , 0.001, P ,
0.001, and P 5 0.006, respectively).
Remarks.—In their review of Atlantic species of Photostomias,Kenaley and Hartel (2005) overlooked the difference in maleAO size (Fig. 4) that distinguishes P. lucingens sfrom P. atrox,a species sympatric with P. lucingens in the subtropical South
184 Copeia 2009, No. 1
Atlantic and Indo-Pacific basins. Eleven specimens hereinassigned to P. lucingens were assigned to P. atrox by Kenaleyand Hartel (2005); seven of these are males with AO widths2.9–4.3% UJL. These 11 specimens, in addition to 29described from Indo-Pacific waters, are assigned to thisnew species, rather than P. atrox, based on the large size ofthe AO (approximately 7% UJL) depicted in the drawing ofthe holotype of P. atrox (Alcock, 1899b:pl. 30, fig. 2).
Etymology.—The name lucingens is derived from the Latinlucis, meaning ‘‘light,’’ and ingens meaning ‘‘of remarkablesize,’’ in allusion to the extreme size of the light-producingPO in males of this species.
Photostomias atrox (Alcock, 1890)Figures 1D, 2D, 3–4, 7; Tables 1, 2
Thaumastomias atrox Alcock, 1890:220, pl. 8, fig. 7. Typelocality: off Madras, India, 18u269N, 85u249E, HMSInvestigator Sta. 97, 1310 fathoms; holotype presumedlost. Goode and Bean, 1896:115, fig. 141 (description,erroneous reproduction of figure after Alcock, 1890);Morrow, 1964:528 (synonymy).
Photostomias atrox.—Alcock, 1899a:150 (new combination,figured); Alcock, 1899b:pl. 30, fig. 2 (figured); Regan andTrewavas, 1930:137 (description after Alcock, 1890);Morrow, 1964:526, 528 (synonymy); Kenaley and Hartel,2005 (description, designation of neotype, occurrence inAtlantic, Indian, and Pacific oceans).
Photostomias sp.—Gibbs, 1984:370 (in part, distribution,mapped as ‘‘n. sp. A’’); Goodyear, 1990:340 (distribution).
Neotype.—MCZ 151289, male, 92.0 mm, Arabian Sea,5u129N, 49u019E, R/V Malcolm Baldridge, 533–141 m, 5 May1995.
Diagnosis.—Males of Photostomias atrox differs from all otherspecies of Photostomias and females differ from all otherspecies Photostomias with the exception of females of P.liemi, by having the following combination of characters:male PO large, 26.8–40.6% UJL, in specimens greater than60 mm (versus PO small to moderate, 7.8–28.1% UJL, in allother species of Photostomias except P. lucingens; Fig. 3,Table 1; Kenaley and Hartel, 2005:table 1); male AO large,5.3–8.6% UJL, in specimens greater than 60 mm (versussmall, 2.4–4.7% UJL in P. lucingens; Fig. 4, Table 1); threetooth patches positioned at posterior end of the first,second, and third basibranchials (versus two basibrancialtooth patches in P. guernei); sum of dorsal- and anal-fin rays50–54, rarely 49 or 55 (versus 57–63, rarely 53, in P.goodyeari; Table 2; Kenaley and Hartel, 2005:table 2); femalesmaturing at approximately 100 mm (versus less than 60 and70 mm in P. lucingens and P. tantillux, respectively; Fig. 5).Females of P. atrox are indistinguishable from females of P.liemi.
Description of males.—Body elongate, deeepest at cleithrum,7.1–12.2% SL (9.2%), tapering slightly to anal-fin origin,4.6–6.6% SL (5.2%), and more abruptly toward shallowcaudal peduncle, 1.5–2.3% SL (2.0%). Soft, corrugated keelalong ventral midline from posteriormost IP photophore toanus. Jaws enormous, extending far posterior to posteriormargin of fleshy orbit; lower jaw length 16.3–20.7% SL(19.9%), upper jaw 14.6–22.5% SL (16.8%). Skin betweendentaries absent, protractor hyoideus exposed. Tip of
basihyal with a white, fleshy, nautilus-shaped tab. Eyelarge, eye width 2.6–5.3% SL (3.9%); a ring of minutephotophores surrounding pupil inside of fleshy orbit.Snout blunt, 2.5–3.9% SL (3.4%); no depression toaccommodate dentary teeth in skin between anterodorsalprocess of premaxilla and anterior margin of fleshy orbit;patches of luminescent tissue usually absent anterior toorbit, if present, only as diffuse patches. Nostril facingforward on snout; a round anteroventral opening aboutone-third width of ovular upper dorsolateral opening.Opercular flap long and sloping posteroventrally toposterior articulation of jaws, inserting dorsal to posteriormargin of fleshy orbit; a single photophore present atmidpoint of posterior margin. Branchiostegal rays 10–13(12), a single photophore embedded in lateral face ofmembrane between each exposed ray; posteriormost raysmedial to inter- and subopercle without inter-ray photo-phore; two anteriormost rays often with two minute inter-ray photophores.
Three cephalic photophores near orbit: AO, SO, and PO(Fig. 1C). AO large in specimens greater than 60 mm, 5.3–9.6% UJL (6.8%). SO minute, round and situated onmidventral margin of fleshy orbit in an elongate pocketwith both a lateral and larger dorsomedial opening. PO anelongate triangle pointing posteriorly; 26.8–46.6% UJL(33.7%) in specimens greater than 60 mm (Figs. 1, 2;Table 1); PO posterior to fleshy orbit with ventral marginaligned with ventral margin of fleshy orbit.
All dentary and premaxillary teeth fixed, not depressible,and curved posterodorsally. Dentary teeth numerous, 15–32 (19), becoming fewer with increase in SL; variable insize, most anterior pair slender, barbed, and enormous,longest dentary tooth 1.8–4.8% SL (3.8%); posteriordentary teeth unbarbed and smaller. Premaxillary teethsmall to moderate, less numerous, 6–10 (8), and variable insize; second anteriormost tooth, or that positioned underfleshy orbit, longest, 0.9–2.5% SL (1.7%), and barbed.Maxillary teeth small, directed posteriorly, and numerous8–31 (22), increasing in number with increase in SL;anterior maxillary teeth smaller, posterior teeth larger.Palatines bearing 2–10 (6) posteromedially directed teeth,arranged serially in anteroposterior row. Basibranchialsbearing three tooth patches each with 2–5 dorsoposterallydirected teeth; a tooth patch positioned at posterior marginof basibranchials of first, second, and third arches.Pharyngobranchials bearing two tooth patches with slen-der, curved, ventroposteriorly directed teeth; anteriorpatch with 3–7 (7) teeth, posterior patch with 7–12 (8)teeth. Gill teeth 5–13 (9) as patches of small tack-like teethor as a single tooth.
Pectoral fin absent in transformed specimens. Pelvic finsextremely elongate, 37.6–51.8% SL (damaged), with 6 rays;proximal ray flattened and separate from remaining fiverays; placed approximately at mid-body; prepelvic length41.3–48.5% SL (44.1%). Dorsal and anal fins placed far backon body and nearly opposite, predorsal length 72.0–86.3%
SL (80.5%), preanal length 71.1–83.5% SL (78.8%); skinextending over proximal third of fin bases. Dorsal-fin rays22–26 (24), anal-fin rays 26–30 (28). Anteriormost rays ofdorsal and anal fins small and tightly spaced, often obscuredby skin. Caudal fin small and forked, lobes falcate, ventrallobe longer than dorsal lobe.
IP 7, two posteriormost photophores separated by a spaceapproximately half of that between other photophores in
Kenaley—Indo-Pacific species of Photostomias 185
the series; PV 14–16 (16), rarely 13 or 17, separated from IPby a space equal to width of approximately 6 photophores;VAV 21–24 (23), rarely 25, separated from PV by a spaceequal to width of approximately 5 photophores, last 3photophores over anal-fin base. OV 14–16 (16), rarely 17,anterior 4 or 5 photophores arched anteroventrally; VAL 20–23 (21), rarely 19, separated from OV by a space equal towidth of 6 photophores. A single small photophore placedapproximately at mid-point of opercular flap on margin ofoperculum; AC 12–14 (14), rarely 15, elevated at level of VALand separated from them by a space equal to width ofapproximately 5 photophores, first AC directly over lastVAV.
Skin thin, scaleless; vertical rows of minute photophoresarranged along lateral aspect of body beginning directlyposterior to opercular flap, each row corresponding to abody segment. Minute masses of luminescent tissue scat-tered over entire body. Color in alcohol black, fading to darkbrown after lengthy preservation. Size large, to 158 mm;females maturing at approximately 100 mm, males atapproximately 85 mm.
Distribution.—Rare in the western Indian Ocean and tropicaland subtropical waters of the Pacific Ocean, from theCelebes Sea in the west to 10uN, 137uW in the tropicalcentral Pacific. Found in tropical and subtropical waters ofthe eastern North Atlantic and South Atlantic to 24uS(Fig. 7). Rare in the western North Atlantic.
Comparison.—The large relative size of the PO and AO ofmale Photostomias atrox (Fig. 3) distinguishes this speciesfrom all other Indo-Pacific species of Photostomias. Atpresent, females of P. atrox are indistinguishable fromfemales of P. liemi. However, as a group, females of P. atroxand P. liemi differ from P. tantillux and P. lucingens on thebasis of size at maturity: P. liemi and P. atrox mature atapproximately 100 mm versus approximately 60 and70 mm in P. lucingens and P. tantillux, respectively(Fig. 5). Females of the Photostomias atrox/P. liemi-groupare also distinguished from P. tantillux on the basis of POsize, P. tantillux having a much smaller PO as a percent ofUJL (Fig. 3). The following diagnostic characters of P. atroxdiffer significantly from other Indo-Pacific species ofPhotostomias: as percent of UJL, male PO larger than P.tantillux and P. liemi; male AO larger relative to UJL thanthat of P. lucingens. In addition, the following charactersdiffer significantly from other Indo-Pacific species ofPhotostomias: HL smaller as a percent of SL than that ofP. liemi; eye larger as a percent of SL than that of P.tantillux; dorsal-fin base shorter as a percent of SL thanthat of P. liemi; prepelvic length shorter as a percent of SLthan that of P. tantillux; number of dorsal-fin rays greaterthan those of P. lucingens and P. tantillux; number of BPphotophores fewer than those of P. tantillux; number of PVphotophores fewer than those of P. tantillux; number ofOV photophores fewer than those of P. tantillux. Inaddition, the following characters differ in allometricgrowth: growth of dorsal-fin base faster than that of P.lucingens; growth of anal-fin base slower than those of P.liemi and P. lucingens; growth of pre-anal length faster thanthat of P. liemi.
Remarks.—Because Photostomias liemi appears to be endemicto the Indo-Pacific basins, female specimens captured in the
Atlantic that are diagnosed as P. atrox or P. liemi, may beprovisionally identified as P. atrox.
DISCUSSION
Four species of Photostomias occur in the Indian andPacific oceans: P. atrox, P. tantillux, P. liemi, and P.lucingens; the latter three are herein described as new.These species are diagnosed largely on the basis of PO andmale AO sizes and relative size at maturity. In addition,many non-diagnostic meristic and morphometric charac-ters differ significantly between species. This resultconfirms the previous indications by Clarke (1974, 1983)and Kenaley and Hartel (2005) of undescribed speciesexisting in these ocean basins. The single most importantdiagnostic character is PO size, a character that has beenutilized to distinguish other malacosteine species, includ-ing the Atlantic species of Photostomias (Kenaley andHartel, 2005) and species of Malacosteus (Kenaley, 2007).On the basis of AO and PO sizes, all males of Indo-Pacificspecies of Photostomias are easily distinguished from oneanother. With the addition of dorsal- and anal-fin raycounts and number of basibranchial tooth patches to thisPO–AO character complex, males of all species of Photo-stomias are clearly diagnosed. Females of Indo-Pacificspecies are less easily diagnosed despite the fact that theycan be divided into large- and small-bodied species, andare distinguished further by the same characters useful indiagnosing males. An analysis of over 35 characters failedto find some combination of these characters thatdiscretely distinguishes females of all species. Withoutthe benefit of any discrete morphological charactersseparating females of P. liemi from P. atrox, and ratherthan relying on spurious evidence (i.e., syntopic speci-mens) to place females of P. liemi, females of P. liemi andthose of P. atrox captured in the Indo-Pacific are leftunassigned. However, because P. liemi has not yet beencaptured in the Atlantic and may be considered endemicto Indo-Pacific basins, Atlantic specimens assigned toeither of these taxa may be provisionally identified as P.atrox.
Clarke’s (1974, 1983) observation of undescribed speciesoff Hawaii in the Pacific Ocean was based entirely on a singlecharacter, size at maturity. As discussed above, this characterwas of particular diagnostic value in distinguishing femalesof P. liemi and P. atrox from the more diminutive P. lucingensand P. tantillux. The size at which P. lucingens and P. tantilluxmature, approximately 54–74 mm (Fig. 5), is considerablysmaller than all other species of Photostomias and, in fact,smaller than all other stomiid species for which these datahave been reported (Clarke, 1974, 1983, 1998, 1999, 2000,2001).
As part of their review of Atlantic species of Photostomias,Kenaley and Hartel (2005) redescribed P. atrox from materialcaptured in all major ocean basins. In the process ofexamining Indo-Pacific specimens, they uncovered a smallnumber of several undescribed species that were onlyalluded to in their 2005 paper. One of these species, hereindescribed as P. lucingens, was recognized as undescribed byKenaley and Hartel (2005), but was not understood to occuroutside the Indo-Pacific. It was only after examiningsignificantly more material in the current study, andreviewing data reported by Kenaley and Hartel (2005), thatP. lucingens was found to occur in the tropical andsubtropical Atlantic as well. The small AO size, the character
186 Copeia 2009, No. 1
distinguishing P. lucingens from P. atrox, was interpreted inthe earlier study merely as intraspecific variation within P.atrox.
KEY TO THE SPECIES OF PHOTOSTOMIAS
Males
1a. Basibranchial with two pairs of tooth patches_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias guernei Collett
(temperate and subtropical North Atlantic)1b. Basibranchial with three pairs of tooth patches _ _ _ _ _ _ _ 22a. Sum of dorsal- and anal-fin rays 57–63, rarely 53; PO
small to moderate (9.6–24.8% UJL in specimensgreater than 60 mm _ _ _ _ _ _ _ _ _ _ _ Photostomias goodyeari
Kenaley and Hartel(tropical and subtropical North Atlantic)
2b. Sum of dorsal- and anal- fin rays 47–55, rarely 56;PO small to large (16.7–46.6% UJL) in specimensgreater than 60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3
3a. PO large (26.9–40.6% UJL) in specimens greaterthan 60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4
3b. PO small UJL to moderate (12.1–23.9%) in speci-mens greater than 60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 5
4a. AO minute (2.4–4.7% UJL) in specimens greaterthan 60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias lucingens
Kenaley, new species(antitropical Pacific, tropical eastern South Atlantic)
4b. AO large (5.3–8.2% UJL) in specimens greater than60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias atrox (Alcock)(western Indian Ocean, tropical and subtropicalPacific, subtropical and tropical South Atlantic,
eastern North Atlantic)5a. PO small (12.1–20.0% UJL) in specimens greater
than 60 mm _ _ _ _ Photostomias tantillux Kenaley,new species
(subtropical and tropical Pacific)5b. PO moderate (21.2–23.5% UJL) in specimens
greater than 60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias liemiKenaley, new species
(Indo-west Pacific, tropical Pacific)
Females
1a. Basibranchial with two pairs of tooth patches_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias guernei
1b. Basibranchial with three pairs of tooth patches _ _ _ _ _ _ _ 22a. Sum of dorsal- and anal-fin rays 57–63, rarely 53; PO
small to moderate (9.4–17.5% UJL) _ _ _ _ _ Photostomiasgoodyeari
2b. Sum of dorsal- and anal- fin rays 47–54, rarely 56;PO small to large (7.9–18.9% UJL) _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 3
3a. PO small to intermediate (7.9–12.8% UJL); devel-oped ova (.0.2 mm) often present in specimenssmaller than 90 mm; concentrated patches ofluminescent tissue often present directly anteriorto orbit; size small, less than 110 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4
3b. PO intermediate to large (11.4–15.5% UJL); devel-oped ova (.0.2 mm) not present in specimens lessthan approximately 100 mm; patches of lumines-cent tissue usually absent anterior to orbit, ifpresent, only as diffuse patches; size large, up to153 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias atrox/P. liemi(probably P. atrox if caught in the Atlantic, P. liemi
endemic to Indo-Pacific)
4a. PO small (7.9–10.4% UJL); developed ova(.0.2 mm) in specimens as small as approximately60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias tantillux
4b. PO moderate (10.0–12.8% UJL); developed ova(.0.2 mm) in specimens as small as approximately60 mm _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Photostomias lucingens
MATERIAL EXAMINED
Specimens are listed alphabetically by institution symboliccode and then numerically by catalog number. Catalognumber is followed by number of specimens examined, sex,size, and capture position. Additional capture data isavailable via the institutions’ online collection databases.
Photostomias atrox. LACM 36081.053, male, 115.1 mm,0u059S, 128u279E, 17 May 1975; MCZ 100854, male,104.0 mm, 31u599N, 64u109W, 17 November 1992; MCZ131423, female, 69.0 mm, 0u349N, 30u439W, 20 November1978; MCZ 131425, male, 96.0 mm, 38u589N, 68u189W, 15October 1982; MCZ 131453, sex undet., 27.0 mm, 3u589N,31u339W, 17 March 1977; MCZ 131492, sex undet.,102.0 mm, 3u589N, 31u339W, 18 March 1977; MCZ131494, male, 56.0 mm, 10u039N, 49u379W, 26 March1977; MCZ 131612, 32.0 mm, 0u039N, 25u009W, 23 February1963; MCZ 131614, sex undet., 41.0 mm, 6u189N, 20u409W,28 February 1966; MCZ 131616, female, 82.0 mm, 7u299N,45u449W, 15 April 1966; MCZ 131668, sex undet., 3, 25.0–40.0 mm, 28u279N, 46u599W, 9 December 1970; MCZ131670, female, 79.0 mm, 23u539S, 8u499W, 19 May 1971;MCZ 131731, male, 106.0 mm, 16u329N, 19u359W, 13November 1970; MCZ 131732, male, 123.0 mm, 16u149N,20u449W, 14 November 1970; MCZ 131733, male, 82.0 mm,15u349N, 24u399W, 20 November 1970; MCZ 131734, 2females, 78.0–85.0 mm, 14u269N, 18u509W, 22 November1970; MCZ 131735, female, 133.0 mm, 3 males, 90–123 mm, 14u439N, 25u279W, 24 November 1970; MCZ131737, male, 123.0 mm, 0u279N, 17u219W, 28 June 1971;MCZ 131744, female, 73.0 mm, 0u279N, 17u289W, 28 June1971; MCZ 151290, male, 98.0 mm, 10u459N, 51u539E, 12August 1995; MCZ 165077, 2 females, 89.4–93.4 mm, male,88.7, 5u359S, 81u099E, 16 April 1986; MCZ 59447, male,100.7 mm, 22u009N, 158u009W, February 1973; MCZ 60385,2, sex undet., 36.0–48.0 mm, 5u339S, 8u429E, 14 June 1971;SIO 69-22, 56.2 mm, 20u489S, 58u119E, 29 July 1968; SIO 77-159, male, 115.2 mm, 12u589N, 146u099W, 18 May 1976;USNM 201129, male, 106.0 mm, 4u529S, 60u029E, 23 August1963; USNM 201130, female, 60.0 mm, 7u279N, 64u419E, 23May 1964; USNM 219032, male, 81.0 mm, 12u079S, 44u209E,18 July 1964; USNM 219034, female, 107.0 mm, 7u149N,59u539E, 16 August 1963; USNM 219035, male, 112 mm,13u579S, 65u059E, 5 June 1964; USNM 219037, 2 females,89.0–127.0 mm, 4u509N, 4u029W, 1 August 1953; USNM219042, sex undet., 41.0 mm, 2u569N, 3u589W, 3 August1963; USNM 219056, female, 97.0 mm, male, 117.0 mm,1u009N, 3u599W, 7 November 1962; USNM 219058, male,63.0 mm, 2u599N, 3u569W, 6 November 1962; USNM219059, male, 110.0 mm, 4u509N, 4u009W, 23 April 1963;USNM 219060, 2 females, 123.0–144.0 mm, 4u519N,4u009W, 14 March 1963; USNM 219061, male, 99.0 mm,4u519N, 4u009W, 1 February 1962; USNM 219062, female,91.0 mm, 4u519N, 4u009W, 13 October 1961; USNM 219064,male, 93.0 mm, 3u579N, 3u559W, 2 August 1963; USNM219065, 2 females, 125.0–134.0 mm, 4u519N, 4u009W, 27December 1961; USNM 219066, female, 61.0 mm, 1u009N,
Kenaley—Indo-Pacific species of Photostomias 187
3u599W, 7 November 1962; USNM 274420, male, 104.2 mm,10u579N, 137u359W, 14 January 1978; USNM 296559, sexundet., 48 mm, 4u349N, 19u399W, 13 April 1971; USNM296572, sex undet., 135 mm, 4u519N, 4u009W, 20 April 1963;USNM 296572, male, 95.0 mm, 4u519N, 4u009W, 20 April1963; USNM 296648, 2 females, 146.0–154.0 mm, 1u049N,18u229W, 12 April 1971; USNM 296680, female, 99.0 mm,5u309S, 16u289W, 9 April 1971; USNM 296681, female,91.0 mm, 4u389N, 19u419W, 13 April 1971; USNM 296685,male, 98.0 mm, 33u459N, 16u009W, 1966; USNM 296697,female, 139.0 mm, male, 117.0 mm, 4u019N, 3u599W, 6 June1962; USNM 296732, 5 females, 47.0–150.0 mm, 3 males,72.0–98.0, 4u369N, 19u409W, 13 April 1971; USNM 296738,female, 71.0 mm, 4 males, 55.0–98.0 mm, 7u329N,20u549W,14 April 1971; USNM 296739, 3 females, 84.0–133.0 mm, 2u299S, 18u589W, 10 April 1971; USNM 296741, 7females, 70–143 mm, 11 males, 61.0–116.0 mm, 10u529N,22u099W, 15 April 1971; USNM 305285, 2 females, 135.0–137.0 mm, male, 124.0 mm, 14u059N, 23uW, 16 April 1971;USNM 307260, 3 females, 76.0–128.0 mm, male, 85.0 mm,2u279S, 19u009W, 10 April 1971; ZMUC20497, 141.5 mm,1u459N, 71u059E, 5 December 1929; ZMUC P2014805, male,96.7 mm, 1u489N, 123u209E, 11 August 1929.
Photostomias liemi. ASIZT P63815, male, 93.4 mm, 22u289N,120u269E, 20 February 2004; SIO 60-252, male, 101.8 mm,19u529N, 156u159W, 14 July 1960; USNM 258712, male,88.7 mm, 21u009N, 158u209W, 16 June 1971; USNM 258714,male, 108.6 mm, 21u259N, 158u209W, 19 March 1971;USNM 258718, male, 95.6 mm, 21u259N, 158u209W, 1March 1971; UW 117086, male, 95.2 mm, approximately22uN, 158uW, 10 October 1977; ZMUC P20584, male,89.4 mm, 10u249S, 114u079E, 10 September 1951.
Photostomias lucingens. AMS I.42719-004, male, 93.1 mm,27u399S, 163u439E, 19 May 2003; CSIRO H505007-09, male,101.6 mm, 31u359S, 167u459E, 26 January 1999; MCZ 59450,2 females, 69.2–76.6 mm, approximately 22uN, 158uW, 2February 1973; SIO 68-483, male, 57.0 mm, 25u479N,178u209E, 19 September 1968; SIO 71-295, female,65.5 mm, 27u309N, 155u179W, 29 September 1971; SIO 71-299, female, 60.6 mm, 27u259N, 155u309W, 30 September1971; SIO 96-41, female, 86.5 mm, 17u579S, 111u579W, 6March 1968; USNM 218983, female, 72.1 mm, 21u209N,158u209W, 14 December 1970; USNM 218994, 2 females,68.3–83.3 mm, 22u009N, 158u009W, 13 November 1969;USNM 258674, female, 53.8 mm, male, 61.4 mm, 21u259N,158u259W, 17 September 1971; USNM 258677, female,76.2 mm, 21u259N, 158u259W, 23 September 1970; UW113443, female, 61.1 mm, male, 55.4 mm, 22uN, 158uW, 31August 1978; ZMUC P20469, male, 92.5 mm, 19u189N,120u139E, 22 May 1929.
Photostomias tantillux. AMS I.19760-015, male, 69.9 mm,19u529S, 170u009E, 12 May 1971; AMS I.27172-004, female,59.9 mm, 15u599S, 172u099E, 25 August 1987; ASIZ P63816,male, 88.1 mm, 22u179N, 120u009E, 22 November 2001;ASIZT P63817, male, 84.7 mm, 22u119N, 120u149E, 23November 2001; ASIZT P63819, male, 86.7 mm, 24u199N,122u049E, 11 September 2002; MCZ 45957, female,63.8 mm, 31u029S, 89u069W, 24 January 1966; MNHN1993-3387, male, 71.8 mm, 12u339S, 143u349E, 6 February1969; NMNZ P39046, female, 88.8 mm, 27u399S, 163u439E,19 May 2003; NSMT P57358, male, 89.1 mm, 33u119N,133u549E, 11 December 1998; SIO 60-239, female, 74 mm,male, 68.7 mm, 5u129N, 143u089W, 6 July 1960; SIO 68-535,male, 76.4 mm, 4u599N, 164u149W, 13 August 1968; SIO 73-
166, female, 74.7 mm, 0u079N, 155u209W, 15 July 1972; SIO77-159, male, 69.4 mm, 12u589N, 146u099E, 18 May 1976;SIO 81-111, male, 62.2 mm, 10u589N, 131u009E, 17 Novem-ber 1980; SIO 88-155, male, 78 mm, 19u269N, 169u419W, 6March 1987; SIO 88-172, male, 64.5 mm, 6u559N, 177u489W,14 March 1987; SIO 90-188, female, 77.4 mm, 8u159S,125u599W, 20 February 1967; USNM 219017, male,100.7 mm, 21u209N, 158u209W, 19 June 1970; USNM219048, 2 females, 53.2–75.2 mm, 5u199N, 161u299W, 22May 1954; USNM 219050, male, 97.1 mm, 4u369N,159u419W, 26 May 1954; USNM 219067, female, 85.7 mm,19u019S, 140u029W, 26 August 1956; USNM 219073, 2females, 87.0–87.2 mm, 1u599N, 148u429W, 4 September1956; USNM 258681, male, 60.7 mm, 21u009N, 158u209W,17 June 1971; USNM 274413, female, 71.7 mm, 2 males,50.2–66.3 mm, 9u509S, 150u039W, 6 December 1977; USNM274433, male, 72.2 mm, 5u039N, 158u039W, 11 February1979; USNM 274435, female, 62.3 mm, male, 75.5 mm,0u599N, 153u019W, 13 November 1979; USNM 292393, male,71 mm, 17u139S, 148u209E, 23 June 1981; USNM 292411,female, 61.9 mm, 14u289S, 147u149E, 4 December 1981;USNM 382260, male, 71.8 mm, 21u239N, 158u189W, 23 April1971; UW 117085, male, 78.4 mm, approximately 22uN,158uW, 6 April 1978.
Photostomias atrox/P. liemi (females). AMS I.25101-003, 2,81.8–108.1 mm, 14u359S, 145u489E, 3 November 1984;ASIZT P63819, 109.6 mm, 21u469N, 120u279E, 29 May2003; LACM 36103.006, 114.7 mm, 7u579N, 121u169E, 4June 1975; LACM 36130.008, 113.5 mm, 9u039N, 122u039E,6 June 1975; MCZ 49139, 77.9 mm, 22uN, 158uW, February1973; NSMT P11194, 140.6 mm, 35u069N, 138u349E, 1 April1967; NSMT P58402, 109.8 mm, 39u029N, 143u309E, 30 July1996; NSMT P66374, 59.2 mm, 26uN, 128uE, 24 April 2002;MCZ 167669, 59.6–114.7 mm, off Kona, HI, February 1973;SIO 61-32, 130.8 mm, 10u269S, 115u169E, 3 November 1960;SIO 70-309, 106.8 mm, 29u229N, 137u189E, 30 August 1970;SIO 70-336, 146.8 mm, 18u49.59N, 124u10.59E, 14 September1976; SIO 70-339, 127.2 mm, 19u239N, 122u579E, 15 Sep-tember 1970; SIO 76-166, 124.1 mm, 14u149S, 150u549E, 6March 1975; SIO 76-374, 109.2 mm, 28u219N, 154u399W, 4February 1973; SIO 89-64, 77.4 mm, 31uN, 159uW, 19 April1989; SIO 90-177, 60.4 mm, 12u489S, 118u549W, 12 February1967; SIO 96-41, 84.1 mm, 17u579S, 111u579W, 6 March1968; SIO 97-88, 119 mm, 31uN, 145uW, 25 April 1972;USNM 258706, 141.8 mm, 21u259N, 158u259W, 23 Septem-ber 1970; USNM 258707, 153.4 mm, 21u259N, 158u259W, 6July 1970; USNM 258709, 105.6 mm, 21u259N, 158u259W, 1March 1971; USNM 258712, 64.7 mm, 21u009N, 158u209W,16 June 1971; USNM 382260, 3 females, 50.2–110.5 mm,21u239N, 158u189W, 23 April 1971; UW 117086, 93.9 mm,22uN, 158uW, 10 October 1977; ZMUC P2014804, 75.7 mm,8u029N, 19u369E, 3 April 1929.
ACKNOWLEDGMENTS
T. Pietsch, D. Stevenson, J. Orr, and Z. Baldwin providedhelpful critiques of the manuscript. The following providedloans, support while visiting their collections, and numer-ous other courtesies: M. Mcgrouther (AMS), Y. Liao and K.Shao (ASIZT), J. Maclaine and O. Crimmen (BMNH), A.Graham (CSIRO), R. Feeney (LACM), K. Hartel and A.Holmes (MCZ), P. Pruvost and L. Nandrin (MNHN), A.Stewart (NMNZ), K. Matsuura (NSMT), H. Walker and C.Klepadlo (SIO), J. Williams, L. Palmer, and K. Murphy
188 Copeia 2009, No. 1
(USNM), and J. Nielsen, T. Menne, and P. Møller (ZMUC). J.Orr and D. Stevenson also assisted with radiographs. K.Maslenikov (UW) deserves special acknowledgment forcuratorial support. Funding for this study was provided bythe William W. and Dorothy T. Gilbert IchthyologyResearch Fund Endowment at the University of Washing-ton, an Ernst Mayr Travel Grant in Animal Systematics fromHarvard University, the Lerner Gray Fund for MarineResearch of the AMNH, and National Science FoundationGrant DEB-0314637, T. Pietsch, principal investigator.
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