Pacific Science (1974), Vol. 28, No.4, p. 457-462

Printed in Great Britain

Skottsbergiliana New Genus (Cucurbitaceae) of Hawaii IslandHawaiian Plant Studies 41 I

HAROLD ST. JOHN2

THE FAMILY CUCURBITACEAE is representedin the native flora of Hawaii only by the genusSiryos. At present there are known 16 species ofit in the islands. Because of its significantdifferences, one of them, S. lasiocephalus, is nowremoved and made the basis of a new genus.

TAXONOMIC TREATMENT

Skottsbergiliana gen. nov. (family Cucurbi­taceae, tribe Sicyoideae)

DIAGNOSIS: Liana herbacea est, caulibusangulosis, cirrhis 2-3-furcatis, foliis alterna­tis petiolatis membranaceis suborbicularibus5-lobatis vel 5-partitis subintegris vel denti­culatis, inflorescentiis masculis femineisqueplerumque ex eodem nodo, floribus masculis inpaniculis et sine lobis calycis, perianthiisvadosis cum 5 lobis rotatis, filamentis connatis,antheris 3 in capite circinatis, floribus femineismultis in capite pedunculato, fructibus utricu­latis sed circum embryonem cum 5 textis,hypanthio chartaceo, pelliculo membranaceo,testa exteriori duro sed interiori subtili, ovulaunica pendenti, semine pendenti ellipsoideo,hilo bilobato, endospermio nullo.

DIAGNOSIS: Herbaceous vines; stems angled;tendrils 2-3-forked; leaves alternate, petioled,membranous, suborbicular, 5-lobed or 5­parted, subentire or denticulate; tendrils,staminate inflorescences, and pistillate in­florescences and tendrils together (or single) ata node and lateral to the petiole base; staminateflowers in panicles; staminate flowers pale,lacking calyx lobes, the perianth shallow andwith 5 rotate lobes; filaments connate, bearingthe 3 anthers coiled in a head; pistillate flowers

I Manuscript received 21 June 1973.2 Bernice P. Bishop Museum, P.O. Box 6037,

Honolulu, Hawaii 96818, U.S.A.

numerous, in a pedunculate head; fruits areutricles but with 5 tissues, 2 chartaceous enve­lopes, a thin pellicle, a hard outer testa, and athin inner testa; ovule single, pendulous; seedpendulous, ellipsoid; hilum 2-lobed; endo­sperm none.

HOLOTYPUS: Skottsbergiliana lasiocephala(Skottsb.) St. John.

DISCUSSION: The closest relative of this newgenus is Siryos which has the fruit either anutricle or a nut, but the seed is enclosed in asingle outer envelope or tissue. Skottsbergilianahas the seed enclosed in three outer envelopes.

In the general texts statements are given as tothe number of the corolla lobes in Siryos.Cogniaux (1881: 346, 869) says that the corollalobes of both staminate and pistillate flowershave 5 lobes. Muller and Pax in Engler andPrantl (1894: 35) say, "Blumen 5 zahIig."Hutchinson (1967: 415) says, "male... corollarotate, deeply 5-partite; female flowers withcorolla as in the male; ..."

The writer now has available 35 Hawaiianspecies of Siryos with the flowers of both sexesrepresented. Only one has the staminate corolla4-lobed; all the others have them 5-lobed.As to their pistillate corollas 15 have them5-lobed; 5 have them 3-lobed; 13 have them4-lobed; and one has them 6-lobed. Fromthese statistics it is obvious that in this detailthe generic description of Siryos should bealtered.

KEY TO SPECIES

Utricle 5-5.5 mm long, fusiform, with a beak0.5-0.8 mm long, not ribbed; seed 2-2.3 mmwide; blades shallowly lobed, as much as iway. . . . . . . . . . . . . . . . . 1. S. lasiocephala.

Utricle 5-7 mm long, ellipsoid, almost beakless,the upper half ribbed; blades 5-partite.

. . . . . . . . . . . . .. 2. S. partita.

457

458 PACIFIC SCIENCE, Volume 28, October 1974

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FIG 1. Skottsbergi/iana /asieccpha/a (Skottsb.) St. John, from lectotype. a, b, habit, xi-; c, staminate bud, x 10;d, staminate flower, x 5; e, pistillate flower, x 5;J, fruiting utricle, x 5; g, longitudinal median section of utricle,with the pericarp, x 5; h, seed, lateral view, x 5; i, seed and hilum, apical view, x 5; j, young shoot, x t.

1. Skottsbergiliana lasiocephala (Skottsb.)comb. nov.

Siryos lasiocephalus Skottsb., Acta Hort.gothoburg. 10: 184-188, fig. 23, 1936.

Fig. 1

DIAGNOSIS OF LECTOTYPE: Liana herbacea est,caule longitudinaliter anguloso pallide rubraad strarnineo et albi-hirsutulo ad subglabrato,internodis 2-11 em longis eis petiolis et cirrhis

subadpresse albi-hirsutulis, cirrhis in nodislateralibus 2-3-furcatis cum caule 8-30 mmlongo compresso anguloso, furcis gracilibus inspiris, petiolis 6-15 mm longis minutealbi-pilosulis, laminis 2-6 em longis 2-5.5 emlatis suborbicularibus sed 5-lobatis lobis latedeltoideis et 1/3 ad centrum extensis, sinibus4-13 mm prafundis latis et vadosis, apicesubito acurninato marginibus subintegris sedapicibus venularum umbonatis distentis, sinu

Hawaiian Plant Studies 41-ST. JOHN

basali anguste U-formato aperto vel dauso,laminis subtiliter papyraceis supra obscureviridibus et remote hispidulis plerumque gla­bratis basibus pilorum punctos albos glutinosospersistentes formantibus infra subadpressealbi-hispidulis pilis plerumque persistentibus,paniculis masculis 3-5 cm longis albi-hirsutu­lis, pedunculo 10-15 mm longo, pedicellis1-2 mm longis, alabastris masculis1.5-2 mmdiametro in tubo et in marginibus hirsutulistubo in radio 1.2 mm longo in centro glanduloso,lobis calycis nullis, lobis perianthii 2-2.2 mmlongis 1.4--1.5 mm latis elliptici-ovatis acutis3-5-nervosis intra capitate glandulosi-puberu­lis extra remote hirsutulis, columna fila­mentarum 1.5 mm longa, 3 antheris 1.5 mmlongis in capite circinatis, floribus femineis50-60 in capite sessili vel subsessili, pedunculo0-5 mm longo, capite 10-15 mm diametrogloboso a pilis longis multis occultatis, lobiscalycis nullis, corolla epigyna in rostro ellip­tico, pistillo 2.3 mm longo, perianthio 1.5 mmdiametro 4--lobato, lobis 0.5 mm longis ellip­ticis subacutis intra glandulosi-punctatis etextra ad apicem, stylo 0.5 mm longo, stig­matibus 3 et 0.3 mm longis cernuis puberulis,utriculo cum hypanthio 5-5.5 mm longo1.8-2.3 mm lato 1.3 mm crasso fusiformi firmechartaceo pallide badio dimidio infero laeviglabro dimidio supero extra lanato pilis 2-3 mmlongis intra catenulate brunneo pilosulo, peri­carpio 3.5-4.7 mm longo lanceoloideo subtilipellucido dimidio supero extra piloso, pelliculo3 mm longo ellipsoideo rostrato subtili glabroseminem vestirenti, semine 1.7-2 mm longo2-2.3 mm lato 0.7-0.9 mm crasso ellipsoideocompresso osseoso pallide badio exlucido, hilo1.8 mm longo apicali elevato stramineo adjuga bina labiis crassis simulanti quoque inmargine descendenti.

DIAGNOSIS OF LECTOTYPE: Herbaceous vine;stem longitudinally ribbed, pinkish to strami­neous, and white hirsutulous to subglabrate,internodes 2-11 cm long, they, the petioles,and tendrils subappressed white hirsutulous;tendril lateral to the petiole base, 2-3-forked,the stalk 8-30 mm long, flattened, angled, theforks slender, spiralling; petioles 6-15 mmlong; blades 2-6 cm long, 2-5.5 cm wide,suborbicular in general outline, 5-lobed, the

459

broadly deltoid lobes extending 1/3 way tocenter, the sinuses 4--13 mm deep, wide andshallow, the apex abruptly acuminate, themargin subentire but with slight umbonateprojections at the veinlet tips, the basal sinusnarrowly U-shaped, open or closed by theoverlapping lobes, texture thin chartaceous,above dark green and sparsely hispidulous,the hairs mostly breaking off, leaving a whiteglutinous base, then this shedding to leave ashallow concave socket, but some hairs per­sisting near the margins and along the principalveins, below abundantly white, half appressedhispidulous, the hairs mostly persistent, butsome deliquescing and forming a viscid whitespot; staminate panicles 3-5 cm long, whitehirsutulous throughout; peduncle 10-15 mmlong; pedicels 1-2 mm long; staminate buds1.5-2 mm in diameter, hirsutulous on the tubeand the margins; calyx teeth wanting; perianth4.5-6 mm in diameter, the tube 1.2 mm inradius, glandular at the center, the 5 lobes2-2.2 mm long, 1.4--1.5 mm wide, elliptic ovate,acute, 3-5-nerved, within capitate glandularpuberulous, without sparsely hirsutulous; fila­ment column 1.5 mm long; anthers 3 and1.5 mm long, coiled in a head; pistillate in­florescences sessile or subsessile and with ahirsutulous peduncle to 5 mm long, axillary,and together with a staminate one; pistillatehead 10-15 mm in diameter, globose, the partswell concealed by a multitude of long hairs;flowers about 50-60 in each head; calyx lobeswanting; corolla epigynous on an ellipticbeaked pistil 2.3 mm long; perianth 1.5 mm indiameter, 4-lobed, the lobes 0.5 mm long,elliptic, subacute, glandular dotted within, andwithout near the apex; style 0.5 mm long;stigmas 3 and 0.3 mm long, ligulate, cernuous,puberulous; utricle of a hypanthium 5-5.5 mmlong, 1.8-2.3 mm wide, 1.3 mm thick, fusiform,firm chartaceous, pale brown, the lower halfsmooth, glabrous, the upper half lanate with­out, not ribbed, with brownish tangled catenu­late hairs 2-3 mm long, and pilosulous within;next within is the pericarp 3.5-4.7 mm long,lanceoloid, thin, transparent, the upper halfpilose without; next within is the pellicle3 mm long, ellipsoid, beaked, thin, glabrous,closely investing but easily peeled from theseed which is 1.7-2 mm long, 2-2.3 mm wide,

460

0.7-0.9 mm thick, ellipsoid, compressed, bony,light brown, dull, the apical hilum raised,1.8 mm long, stramineous, like 2 pairs of fatlips in a line, one running down each edge.

LECTOTYPE: Hawaiian Islands, Hawaii Island,N. Kona, along the road near Huehue on aalava, 26/9/1926, C. Skottsberg 1,947 (HISH), heredesignated. Isotype (GOTH).

SPECIMENS EXAMINED: Hawaiian Islands,Hawaii Island, 20 miles from Waimea towardKona, in aa desert along road, Aug. 18, 1926,O. Degener 9,896A (NY); ditto, 21 miles,Degener 18,042 (G, GH, MASS, NY); ditto betweenPuuwaawaa and Waimea, dry lava region,Aug. 18, 1926, Degener 18,043 (NY).

DISCUSSION: In the original publication ofSicyos lasiocephalus Skottsberg did not designatea type. He cited his own collection, no. 1,947,then mentioned and gave descriptive notes ontwo collections by Degener. Both of his figureswere drawn partly from his own and partlyfrom Degener's specimens, and he accepted allthree as of the same species. Consequently it isnecessary to select a lectotype, as is done above.

Skottsberg's diagnosis and discussion of thisunique species was discriminating, but he didnot note that the pericarp was pilose without,and the hypanthium was pilosulous within.This has been confirmed by study of the lecto­type.

Skottsberg (1936: 187) considered theclosest relative of his Sicyos lasiocephalus to beS. hispidus Hbd. However, that species has verydifferent fruits, and is now placed in the sectionCladocarpa, due to its fruits being woody andwith numerous strong branches from it thatare long hairy.

2. Skottsbergiliana partita sp. nov.

Fig. 2

DIAGNOSIS HOLOTYPI: Liana herbacea est,caulibus longitudinaliter pluriangulatis sub­viridibus ad stramineis albi-pilosulis et pilisin nodis persistentibus alibi glabratis, inter­nodis 5-7.5 em longis, cirrhis bifurcatis innodis lateralibus cum caule 14-23 mm longoanguloso sparse puberulo furcis gracilibus inspiris et ad basim extra puberulis, petiolis

PACIFIC SCIENCE, Volume 28, October 1974

8-25 mm longis dense capitati-glandulosi­hispidulis, laminis 2-4 em longis 2.5-6 emlatis suborbicularibus sed palmatim 5-partitispartis oblanceolatis subintegris sed remote exapicibus venularum denticulatis supra remotehispidulis pilis cum basibus albis pustulatisinfra grosse hispidulis pilis inaequalibus exbasibus albis pustulatis, sinu basali U-formatoaperto vel clauso laminis subtiliter chartaceissupra obscure viridibus infra viridibus supranervis puberulis infra nervis et intervallis hispi­dulis, paniculis masculis 2-2.5 em longisglandulose pilosulis, pedunculo 12 mm longo,pedicellis 1-2 mm longis (alabastris non visis),inflorescentia feminali 10-16 mm longo utvidetur sessili sed cum pedunculo 5-8 mm longopilosulo cum 30-48 floribus, capiti in fructu10-16 mm diametro globoso cum pilis albismultis, calyce nullo, floribus epigynis J;npistillo ellipsoideo, perianthio 1.8 mm diametrotubo 0.4 mm diametro cum 3 lobis 0.5 mmlongis late ovatis subacutis glandulose atomi­feris extra sparse intra copiose trinervosis,stylo 0.7 mm longo, 3 lobis stigmatis 0.3 mmlongis oblongis cernuis, utriculis in fructu5-7 mm longo 1.8-2 mm lato ellipsoideo acutofere erostrato firme chartaceo stramineo dimi­dio supero longitudinaliter costato et catenulatealbi-piloso pilis 2.5-3 mm longis, intra suprain dimidio supero pilosis, pericarpio 3.3 mmlongo late ellipsoideo rostrato subtiliter mem­branaceo pellucido in tertia supera extrapilosulo, semine 1.8-2.3 mm longo 1.3-1.7 mmlato 0.5 mm crasso ellipsoideo pallide badioexlucido, hilo 0.7 mm longo apicali elevatoplano stramineo juga bina labiarum rotun­datarum in linea simulanti.

DIAGNOSIS OF HOLOTYPE: Herbaceous vine;stems longitudinally several ribbed, greenish tostramineous, and white pilosulous, the hairspersisting at the nodes, glabrate elsewhere;internodes 5-7.5 em long; tendril lateral to thepetiole base, 2-forked, the stalk 14-23 mmlong, angled, sparsely puberulous, the forksslender, spiralling, near the base puberulous onthe outer side; petioles 8-25 mm long,densely capitate glandular hispidulous; blades2-4 em long, 2.5-6 em wide, suborbicular inoutline but palmately 5-parted, the partsoblanceolate, subentire but remotely denticu-

Hawaiian Plant Studies 41-ST. JOHN 461

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late by excurrent veinlet tips, above remotelyhispidulous from white pustulate bases, belowcoarsely hispidulous, the hairs of unequalwidth, from white pustulate bases, the basalsinus U-shaped, open or closed, texture thinchartaceous, above dark green, below green,the veins above puberulous, but below scabroushispidulous like the intervals; staminate panicles2-2.5 cm long, glandular pilosulous; peduncle12 mm long; pedicels 1-2 mm long (the budsnot seen); pistillate inflorescence 10-16 mmlong, appearing sessile, but with a peduncle5-8 mm long, pilosulous; fruiting pistillatehead 10-16 mm in diameter, globose, verywhite hairy; flowers 30-48 to a head; calyxwanting; flowers epigynous on the ellipsoidpistils, the pistillate perianth 1.8 mm indiameter, the tube 0.4 mm in diameter, the3 lobes 0.5 mm long, broadly ovate, subacute,glandular atomiferous, sparsely so without,abundantly so within, 3-nerved; style 0.7 mmlong, the 3 stigmatic lobes 0.3 mm long,oblong, cernuous; in fruit the utricle 5-7 mmlong, 1.8-2 mm wide, ellipsoid, acute, almostbeakless, firm chartaceous, stramineous, theupper half longitudinally ribbed, and whitecatenulate pilose, the hairs 2.5-3 mm long,within pilose on the upper half; next within isthe pericarp 3.3 mm long, broadly ellipsoid,beaked, white, thin membranous, translucent,pilosulous without on the upper third; andseated within this is the seed 1.8-2.3 mm long,1.3-1.7 mm wide, 0.5 mm thick, ellipsoid, lightbrown, dull; the hilum apical, raised, flat,0.7 mm long, stramineous, like two pairs ofrounded lips in a line.

HOLOTYPUS: Hawaiian Islands, Hawaii Island,20 miles from Waimea toward Kona, aadesert, Aug. 17-18, 1926, O. Degener [9,896](GOTH). Isotype (NY). Mounted with the holo­type is a second stem with broader leaf lobesand less mature fruit. This is deemed to be S.lasiocephala, and is renumbered 9,896A.

DISCUSSION: The two species of Skotts­bergiliana differ as follows: S. lasiocephala has the

FIG. 2. Skottsbergiliana partita St. John, from holotype.a, habit, x t; b, c, leaves, x t; d, fruiting utricle, withpistillate flower, x 5; e, longitudinal median section ofutricle and pericarp, with seed, x 5 ;.f, seed, lateral view,x 5; g, seed and hilum, apical view, x 5.

462

pistillate peduncle 0-5 mm long; pistillateheads with about 50-60 flowers; utricle in fruit5-5.5 mm long, fusiform, not ribbed; seed1.7-2 mm long, 2-2.3 mm wide; staminatepanicles 3-5 cm long, white hirsutulous; stemswhite hirsutulous to subglabrate; petioles6-15 mm long, finely white pilosulous; blades2-6 cm long, shallowly lobed, as much as 1/3way. S. partita has the pistillate peduncles5-8 mm long; pistillate head with 30-48flowers; utricle in fruit 5-7 mm long, ellipsoid,the upper half ribbed; seed 1.8-2.3 mm long,1.3-1.7 mm wide; staminate panicles 2-2.5 cmlong, glandular pilosulous; stems white pilo­sulous, the internodes glabrate; petioles 8-25mm long, densely capitate glandular hispidu­lous; blades 2-4 cm long, palmately 5-parted.

The new epithet is the Latin participlepartitus, divided or parted, and it is given withreference to the deeply parted blades.

PACIFIC SCIENCE, Volume 28, October 1974

LITERATURE CITED

COGNJAUX, ALFRED. 1881. Cucurbitacees.Pages 325-1008 in A. De Candolle and C. DeCandolle. Monographiae Phanerogamarum.Vol. 3. G. Masson, Paris.

HUTCHINSON, JOHN. 1967. The genera offlowering plants. Vol. 2, Dicotyledones. Atthe Clarendon Press, Oxford, 659 pp.

MULLER, E. G. 0., and F. PAX. 1894. Pages1-39, figs. 1-22 in A. Engler and K. Prantl.Die naturlichen Pflanzenfamilien. Vol. 4,no. 5, Cucurbitaceae. Verlag von WilhelmEngelmann, Leipzig.

SKOTTSBERG, C. 1936. Vascular plants from theHawaiian Islands. II. Acta Hort. gothoburg.10: 97-193, figs. 1-23.