Xenopus laevisAfrican Clawed Frog By Nathan Garvey Geographic Range Habitat Physical Description Development Reproduction Lifespan/Longevity Behavior Food Habits Economic Importance for Humans: Positive Economic Importance for Humans: Negative Conservation Status Contributors References Geographic RangeXenopus laevis occurs naturally in southern Africa. There are substantial introduced populations in California, Chile, Great Britain, and probably many other locations around the world. (Nieukoop and Faber, 1994) Biogeographic Regions nearctic introduced palearctic introduced ethiopian native HabitatXenopus laevis lives in warm, stagnant grassland ponds as well as in streams in arid and semi-arid regions. The ponds are usually devoid of any higher plant vegetation, and covered in green algae. Xenopus laevis can tolerate wide variation in water pH, but the presence of metal ions proves toxic. It thrives in temperatures from 60 to 80 degrees Fahrenheit. It is almost totally aquatic, only leaving the water when forced to migrate.(Nieuwkoop and Faber, 1994; Beck, 1994; Kaplan, 1995, Jack Crayon, personal communication) Habitat Regions temperate tropical freshwater Aquatic Biomes lakes and ponds rivers and streams Physical DescriptionXenopus laevis has a unique morphology because it lacks a tongue and a visible ear. The body is flattened and head is wedge-shaped and smaller than the body. It has two small eyes found on the top of the head and no eyelids. Its front limbs are small and are not webbed, and its hind legs are large and webbed and the three inside toes on either foot have claws. It has smooth slippery skin which is multicolored on its back with blotches of olive gray or brown and gray, while the underside is creamy white with a yellow tinge. It has lateral lines along its back. Males weigh about 60 grams, are about 5 to 6 centimeters long, and lack a vocal sac, which most male frogs have. Females weigh about 200 grams, are about 10 to 12 centimeters long, and have cloacal extensions at the end of the abdomen.(Kaplan, 1995; Chang 1998) Other Physical Features ectothermic heterothermic bilateral symmetry Sexual Dimorphism female larger Range mass60 to 200 g2.11 to 7.05 oz Range length5 to 12 cm1.97 to 4.72 in Average basal metabolic rate0.012 WAnAge Development Development - Life Cycle metamorphosis ReproductionXenopus laevis is sexually mature in 10 to 12 months. Mating can take place during any time of the year, but is most common in the spring, and can take place up to four times per year. Males vocalize during the evening to attract females. Although the male lacks a vocal sac, it produces a mating call by rapid contractions of the intrinsic laryngeal muscles. This mating call sounds like alternating long and short trills. After the female hears this, she responds with either an acceptance call (a rapping sound) or a rejection call (slow ticking sound). This is a nearly unique behavior in the animal world; rarely does a female answer the males call. Mating often takes place at night, when there are few disturbances. The male develops mating pads on the underside of his forearms and hands. The mating embrace, amplexus, is pelvic, whereas most frogs have axillary (front limb) amplexus. The female can release hundreds of sticky eggs during the 3 to 4 hour event, which are typically attached to plants or other anchors, one or more at a time. The eggs grow into tadpoles, which filter feed. The tadpole metamorphoses into a small froglet, with the tail being absorbed into the body and sustaining its nutritional requirements during this period, which lasts about 4 to 5 days. The total change from egg to small frog takes about 6 to 8 weeks.(Kaplan, 1995; Beck, 1994; Chang, 1998; Kelley, 1998, Jack Crayon, personal communication) Key Reproductive Features iteroparous year-round breeding gonochoric/gonochoristic/dioecious (sexes separate) sexual fertilization external oviparous Breeding intervalAfrican clawed frogs can breed up to 4 times each year. Breeding seasonMating can take place during any time of the year, but is most common in the spring. Range age at sexual or reproductive maturity (female)10 to 12 months Range age at sexual or reproductive maturity (male)10 to 12 monthsLifespan/LongevityAfrican clawed frogs can reach 15 to 16 years old in wild and feral populations. Captive animals have been known to live as long as 20 years. Range lifespanStatus: wild16 (high) years Range lifespanStatus: captivity20 (high) years Average lifespanStatus: captivity8.8 yearsMax Planck Institute for Demographic Research Average lifespanStatus: captivity15.0 yearsMax Planck Institute for Demographic Research BehaviorXenopus laevis is a rather inactive creature. It is incredibly hardy and can live up to 15 years. At times the ponds that Xenopus laevis is found in dry up, compelling it, in the dry season, to burrow into the mud, leaving a tunnel for air. It may lie dormant for up to a year. If the pond dries up in the rainy season, Xenopus laevis may migrate long distances to another pond, maintaining hydration by the rains. It is an adept swimmer, swimming in all directions with ease. It is barely able to hop, but it is able to crawl. It spends most of its time underwater and comes to surface to breathe. Respiration is predominantly through its well developed lungs; there is little cutaneous respiration(Kaplan, 1995; Simmonds 1985) Key Behaviors natatorial diurnal nocturnal motile sedentary solitary Food HabitsXenopus laevis is a scavenger and eats living, dead, or dying arthropods and other pieces of organic waste. It has a voracious appetite and attacks anything that passes in front of it. It uses extremely sensitive fingers, an acute sense of smell, and its lateral line systems to locate food. Lateral line systems, usually found in fish, detect vibrations in the water. It uses a hyobranchial pump to suck food into its mouth. The claws on its hind feet tear apart larger pieces of food. Tadpoles are exclusively filter feeders(Avila and Frye, 1977; Beck, 1994) Primary Diet carnivore insectivore scavenger Animal Foods insects aquatic or marine worms aquatic crustaceans Economic Importance for Humans: PositiveXenopus laevis has been used extensively as a laboratory research animal, mostly in the field of vertebrate embryology because females are prolific egg layers and embryos are transparent, making it easy to observe the development of the embryo. During the 1940's, female X. laevis were injected with the urine of a woman. If the human was pregnant, then the injected frog would start to produce eggs. Xenopus laevis was the first vertebrate cloned in the laboratory. Magainins are a family of antibiotics found in the skin of X. laevis, which heals wounded skin rapidly. Magainin is an antibiotic, antifungal, antiparasitic, and antiviral, probably useful to the frog because of the stagnant, microbe filled waters in which it lives in. These magainins have been tested as an antibiotic cream, which works just as well as an oral antibiotic, but without the side effects. Xenopus laevis is also used in lab because it is very easy to care for, breed, and observe. Positive Impacts source of medicine or drug research and education Economic Importance for Humans: NegativeHuman activities have transplanted this African frog all over the globe, where some claim it is pushing native species out of their niche (Beck 1994). Others argue that there is no documented case of this occurring (Jack Crayon, pers. comm.)Conservation StatusIt is an invasive species all over world because it was used in human pregnancy tests in the 1940's. When more effective means of pregnancy tests were made available, many X. laevis were released all over the world. IUCN Red List Least Concern More information ContributorsNathan Garvey (author), University of Michigan-Ann Arbor. GlossaryEthiopianliving in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

Nearcticliving in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

Palearcticliving in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

bilateral symmetryhaving body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.carnivorean animal that mainly eats meatdiurnal1. active during the day, 2. lasting for one day.druga substance used for the diagnosis, cure, mitigation, treatment, or prevention of diseaseectothermicanimals which must use heat acquired from the environment and behavioral adaptations to regulate body temperatureexternal fertilizationfertilization takes place outside the female's bodyfertilizationunion of egg and spermatozoanfreshwatermainly lives in water that is not salty.heterothermichaving a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.insectivoreAn animal that eats mainly insects or spiders.introducedreferring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.iteroparousoffspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).metamorphosisA large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.motilehaving the capacity to move from one place to another.natatorialspecialized for swimmingnative rangethe area in which the animal is naturally found, the region in which it is endemic.nocturnalactive during the nightoviparousreproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.scavengeran animal that mainly eats dead animalssedentaryremains in the same areasexualreproduction that includes combining the genetic contribution of two individuals, a male and a femalesolitarylives alonetemperatethat region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).tropicalthe region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.year-round breedingbreeding takes place throughout the yearReferencesAvila, Vernon L. and Frye, Patricia G. 1978. Feeding behavior of the African Clawed frog (Xenopus laevis Daudin):effect of prey type. Journal of Herpetology 12(3).Beck, Alan. 1994. http://gto.nsca.uiuc.edu/pingleto/xenopus.htmlKaplan, Melissa. 1995. Natural History of the Upland Clawed Frog. http://www.sonic.net/~melissk/xenopus.htmlKelley, Darcy B. 1998. http://www.cc.columbia.edu/cu/biology/faculty/kelley.htmlNieukoop, P.D and Faber, J. 1994. Normal Table of Xenopus Laevis (Daudin). Garland Publishing, Inc., New York and LondonSimmonds, Mark P. 1985. African Clawed toad survey. British Herpetological Society Bulletin No. 13.ADW Pocket Guides on the iOS App Store! The Animal Diversity Web team is excited to announce ADW Pocket Guides!Read more... Connect with usHelp us improve the site by taking our survey. Facebook Twitter Pinterest SearchTop of FormEnter search text Search in feature Bottom of Form Explore Data @ Quaardvark Search Guide Navigation LinksInformation Pictures Classification Classification Kingdom Animalia animals Animalia: information (1) Animalia: pictures (19739) Animalia: specimens (7518) Animalia: sounds (722) Animalia: maps (42) Phylum Chordata chordates Chordata: information (1) Chordata: pictures (14662) Chordata: specimens (7238) Chordata: sounds (709) Subphylum Vertebrata vertebrates Vertebrata: information (1) Vertebrata: pictures (14625) Vertebrata: specimens (7236) Vertebrata: sounds (709) Class Amphibia frogs, salamanders, and caecilians Amphibia: information (1) Amphibia: pictures (607) Amphibia: specimens (13) Amphibia: sounds (20) Family Pipidae Tongueless Frogs Pipidae: information (1) Pipidae: pictures (9) Genus Xenopus Xenopus: pictures (3) Species Xenopus laevis African Clawed Frog Xenopus laevis: information (1) Xenopus laevis: pictures (1)

XenopusDari Wikipedia bahasa Indonesia, ensiklopedia bebasBelum Diperiksa?Xenopus

Xenopus laevis

Klasifikasi ilmiah

Kerajaan:Animalia

Filum:Chordata

Kelas:Amphibia

Ordo:Anura

Famili:Pipidae

Genus:XenopusWagler, 1827

Spesies

Xenopus amietiXenopus andreiXenopus borealisXenopus boumbaensisXenopus cliviiXenopus fraseriXenopus gilliXenopus itombwensisXenopus laevisXenopus largeniXenopus longipesXenopus muelleriXenopus petersiiXenopus pygmaeusXenopus ruwenzoriensisXenopus tropicalisXenopus vestitusXenopus victorianusXenopus wittei

Xenopus adalah katak yang berasal dari Sahara, Afrika.[1] Xenopus dikenal sebagai katak pencakar dari Afrika atau Platanna, karena memiliki kaki berbentuk cakar yang digunakan untuk merobek makanannya.[1] Xenopus berbentuk bulat, seperti telur dan memiliki kulit yang sangat licin.[2] Pada umumnya, xenopus ditemukan dalam air dengan warna hijau keabu-abuan, serta selalu berganti kulit pada setiap musim.[2] Xenopus mempunyai waktu hidup sekitar 5-15 tahun.[2] Xenopus jantan dan betina dapat di bedakan berdasarkan bentuk.[2] Bentuk xenopus jantan biasanya sekitar 20% lebih kecil dari xenopus betina, dengan tubuh dan kaki agak langsing.[2] Xenopus betina lebih gemuk dengan tonjolan di atas belakang kaki, karena tonjolan itu merupakan tempat telur.[2] Jenis xenopus yang terkenal adalah xenopus laevis dan xenopus tropicalis.[2] Kedua jenis xenopus ini digunakan dalam laboratorium sebagai subyek penelitian.[2]

Klasifikasi : Bangsa Anura, Suku PipedaeDeskripsi : Katak ini ukuran tubuhnya kecil, panjang tubuhnya hanya dapat mencapai 6-13 cm dengan berat tubuh sekitar 50 g. Tubuh nampak gemuk tertutup kulit berwarna putih, bentuk kepala meruncing, mata berukuran kecik agak menonjol berwarna oranye. Jari-jari kaki mempunyai selaput renang, Warna dasar kulit putih, mata oranye, cakar jari kaki runcing.Perilaku : Menyukai hidup soliter, aktif pada malam hari, hanya saat musim kawin katak ini akan berkumpul dalam jumlah yang banyak, seperti anggota Anura lainnya menyukai menangkap mangsanya saat bergerak. Katak ini pandai berenang.Pada waktu siang hari, katak ini lebih suka berendam. Sesekali katak ini akan muncul ke permukaan untuk mengambil oksigen.Reproduksi : Pembuahan eksternal terjadi di dalam air pada waktu musim semi dan panas. Jumlah telur yang dihasilkan seekor betina dapat mencapai 1.000 butir, telur akan menetas 4 hari setelah dibuahi. Larva katak bernapas dengan insang dan akan berubah bernapas dengan paru-paru setelah dewasa.Pakan : Berbagai jenis invertebrata seperti larva capung, larva ikan, berudu katak lainnya.Habitat : Perairan seperti sungai, kolam, danau dan rawa-rawa. Tersebar di Afrika Selatan.- See more at: http://gembiralokazoo.com/collection/katak-badut.html#sthash.rDnodq16.dpuf