Island bush rat
| Island bush rat | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Neotoma insularis | ||||||||||||
| Townsend , 1912 |
The island bush rat ( Neotoma insularis ) is an extremely rare or already extinct species of rodent from the genus of the American bush rats ( Neotoma ). It is or was endemic to Isla Ángel de la Guarda in the Gulf of California .
features
| 1 | · | 0 | · | 0 | · | 3 | = 16 |
| 1 | · | 0 | · | 0 | · | 3 |
The head-torso length is 174 to 178 mm, the tail length 113 to 162 mm, the ear length 27 to 38 mm and the hind foot length 30.5 to 37 mm. No specific data are available on weight. The island bush rat is a medium-sized species that resembles the desert bush rat ( Neotoma lepida ). The back is pink-yellow-brown to gray-yellow-brown. The belly is lighter gray. The hair base is gray, the ends of the hair are lighter. The short tail is two-colored with a dark gray top and a light gray bottom. The tail length is about 71 percent of the head-trunk length. The glans is short, thickened, and covered with bristles except for the distal tip. The snout is visibly shorter and stronger than that of the desert bush rat. The zygomatic arches are broadly squared in front and behind. The septum of the incisor hole consists of a short ploughshare part and an elongated opening. The timpani are long and narrow. The dentition is stronger than that of the desert bush rat. The tooth formula is I 1/1 - C 0 / 0- PM 0 / 0- M 3/3, so the island bush rat has a total of 16 teeth.
habitat
The Isla Ángel de la Guarda is a very dry island with an annual rainfall of 100 mm. The dominant vegetation consists of cacti of the genus Cylindropuntia , Parkinsonia and balsam trees . It is unclear whether the island bush rat uses all habitats at altitudes from 0 to 1300 m. The few known places where specimens have been sighted are on the northern and southern tips of the island, due to the difficult access to the center of the island.
Way of life
The island bush rat is likely nocturnal and feeds on cacti to some extent. Further information about the way of life is not known.
Systematics
The island bush rat was described as a separate species by Charles Haskins Townsend in 1912 . In 1932 it was classified by William Henry Burt as a subspecies of the desert bush rat ( Neotoma lepida insularis ). However , a study published in 2007 by James L. Patton and colleagues concluded that species status should be supported because of the significant differences in mtDNA data, skull morphology and penis .
status
In 2017 the island bush rat was included in the IUCN Red List's “ data deficient ” category. Data about the population development are not available and since an extensive search expedition in 1997 was unsuccessful, the extinction of this species is already feared.
literature
- Gerardo Ceballos: Mammals of Mexico . Johns Hopkins University Press, 2014, ISBN 978-1421408439 . P. 305
- Ulyses Pardiñas, Dennisse Ruelas, Jorge Brito, Lisa Bradley, Robert Bradley, Nicté Ordóñez Garza, Boris Kryštufek, Joseph Cook, Erika Cuéllar Soto, Jorge Salazar-Bravo, Gregory Shenbrot, Elisandra Chiquito, Alexandre Percequillo, Joyce Prado, Rudolf Haslauer Patton, Livia León-Paniagua: Family Cricetidae (True Hamsters, Voles, Lemmings and New World Rats and Mice) In: Handbook of the Mammals of the World. Volume 7: Rodents II, Lynx Edicions, Barcelona 2017, ISBN 978-84-16728-04-6 , p. 362
Web links
- Neotoma insularis inthe IUCN Red List of Threatened Species 2017.3. Posted by: Patton, J. & Álvarez-Castañeda, ST, 2017. Retrieved January 3, 2018.
Individual evidence
- ↑ CH Townsend: Mammals collected by the 'Albatross' expedition in Lower California in 1911, with descriptions of new species. Bulletin of the American Museum of Natural History, 31, 1912, pp. 117-130
- ^ WH Burt: Descriptions of heretofore unknown mammals from islands in the Gulf of California, Mexico. Transactions of the San Diego Society of Natural History, 7, 1932, pp. 161-182.
- ↑ James L. Patton, David G. Huckaby, Sergio Ticul Álvarez-Castañeda: The Evolutionary History and a Systematic Revision of Woodrats of the Neotoma lepida Group. University of California Press, 2007
- ^ ST Álvarez-Castañeda, P. Cortés-Calva: Familia Muridae. In: Mamíferos del Noroeste de México (ST Álvarez-Castañeda and JL Patton, eds.). Centro de Investigaciones Biologícas Noroeste, SC La Paz, Baja California, México, 1999, pp. 445-570