Crocidura caudipilosa
| Crocidura caudipilosa | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Crocidura caudipilosa | ||||||||||||
| Esselstyn , Achmadi , Handika , Giarla & Rowe , 2019 |
Crocidura caudipilosa is a type of shrew from the genus of the white- toothed shrew ( Crocidura ). It occurs widely across Sulawesi and inhabits both deeper tropical rainforests and higher humid mountain forests. It is a slender shrew whose special characteristic is the thickly hairy tail. There is hardly any information about the way of life of the animals; according to individual observations, some of them may be tree-dwelling. The species was scientifically introduced in 2019.
features
Habitus
Crocidura caudipilosa is a slender representative of the white- toothed shrews . The total length of the animals varies between 14.5 and 18.3 cm, of which the tail takes 7.9 to 9.8 cm. It thus has 100 to 120% of the length of the rest of the body. Compared to other white-toothed shrews from Sulawesi , the tail is rather medium-long. The body weight varies from 6.5 to 12 g. The body fur shows a grayish brown color on the back, the underside is slightly lighter in color. The hairs grow to an average of 4 to 7 mm long, but can also be longer in individuals from altitudes above 2000 m. The back hair has gray bases and short brown tips, while the belly hair is medium gray at the base and translucent at the tip. This gives the fur an overall silvery sheen. The color of the fur is somewhat reminiscent of the slender white-toothed shrew ( Crocidura elongata ) and the Temboan white-toothed shrew ( Crocidura rhoditis ), all other representatives of the genus Crocidura from Sulawesi are darker in color. The tail is two-colored with a brown tint on top and gray below. This is caused by the roughly 2 mm long, tightly laid hair that covers the entire tail and the brown bases of which are more extensive on the back of the tail than on the underside of the tail. The tip of the tail is silvery. Occasionally, 7 to 10 mm long bristle hairs penetrate the tail fur. Some of these have brown bases and translucent tips or they are translucent along their entire length. The dense and, above all, comparatively long tail hairs distinguish Crocidura caudipilosa from other white- toothed shrews of the Sunda Islands and the Philippines . The feet show a dark brown color on the back, while the toes are lighter and the claws are translucent. The latter are surrounded by a tuft of unpigmented hair. The soles of the feet are typically scaly and covered by large, lighter colored leather pads. On the rear foot, the padding of the big toe ( thenar ) exceeds that of the opposite side ( hypothenar ), and on the forefoot both are roughly the same size. The hind foot is 15 to 19 mm long. The snout is similar to that of the other white-toothed shrews. There are numerous vibrissae , the length of which on the upper lip is 5 to 23 mm. They are shorter on the cheeks and hardly longer than 5 mm on the chin. The ear length varies between 8 and 13 mm.
Skull and dentition features
The skull is slender with a total length of 19.6 to 22.2 mm and a width at the cranium of 9 to 9.9 mm. When viewed from the side, the forehead line is rather straight with a slight indentation over the orbit . The interocular region narrows significantly towards the front, but is generally relatively wide. The occiput is more developed than the crest , which is only weakly indicated. The maxillary sinus forms a flat arch on both sides of the brain capsule. It is indicated through a small opening just 1 mm below the tip of the arch. The palate is narrow on the underside of the skull . On the lower jaw rises a high crown process, which in side view has the shape of a broad, almost isosceles triangle. The teeth are less robust than other white-toothed shrews from Sulawesi. It consists of 28 teeth with the following tooth formula: The two rear upper incisors , the rear lower incisor and the upper and lower canine teeth are each single-pointed. In the upper row of teeth, the third incisor slightly exceeds the second in height, which roughly corresponds to the slender white-toothed shrew and the Temboan white-toothed shrew, but differs from the small black-footed white-toothed shrew ( Crocidura lea ) with its significantly larger rearmost incisor. The anterior shear edge (parastyle) of the upper premolar makes only slight contact with the canine. The upper row of teeth is 8.6 to 9.7 mm long, the molars take up 4.5 to 5.1 mm.
distribution
Crocidura caudipilosa is endemic to Sulawesi , but has a wide distribution there. Almost a dozen sites have been documented in the provinces of Sulawesi Tengah (Central Sulawesi), Gorontalo , Sulawesi Barat (West Sulawesi), Sulawesi Selatan (South Sulawesi) and Sulawesi Utara (North Sulawesi). The species occurs there at altitudes of 500 to 2300 m. The species inhabits both tropical rainforests of the lowlands and humid mountain forests. It may be restricted to forest landscapes, but only a few open areas have been explored.
Way of life
Little information is available about the way of life of Cocidura caudipilosa . The animals live on the ground, but can obviously also climb trees, as an individual was caught at a height of 1.5 m. A partly tree-climbing way of life ( scansorial ) is assumed for some species of the white-toothed shrew with an extremely long tail, but direct evidence in nature is rare.
Systematics
Crocidura caudipilosa is a kind from the genus of crocidura ( Crocidura ) from the family of shrews (Soricidae). More than 190 species are assigned to the form-rich genus, making it the most diverse among the shrews. According to molecular genetic evidence, however, it is possibly paraphyletic , as some forms such as the pied desert shrew ( Diplomesodon ) and the Congo eyelash shrew ( Paracrocidura ) are deeply embedded in Crocidura . Different clades can be distinguished, such as an Asian, an Afrotropic, a West Palearctic and an Old World with different Eurasian and African species. The white-toothed shrews are probably the youngest branch within the phylogenetic development of the shrews. The majority of the representatives are found in Africa today, a further, not inconsiderable proportion in Asia. The origin of the Crocidura line is likely to be found in Eurasia, where it separated from the other lines around 8 to 6.8 million years ago and from here probably settled in the other areas of distribution today.
From Sulawesi half a dozen have been approximately described species. These are the slim white-toothed shrew ( Crocidura elongata ), the small black-footed white-toothed shrew ( Crocidura lea ), the small Sulawesi white-toothed shrew ( Crocidura levicula ), the musser -white-toothed shrew ( Crocidura musseri ), the black-footed white-toothed shrew ( Cricdura nigripes ) and the Temboan white-toothed shrew ( Crocidura rhoditis ). Except for the black-footed white-toothed shrew, which belongs to the Asian clade, the other forms form part of the ancient line and, according to the genetic data, are more closely related to one another. They therefore form a local radiation group on the island. This also includes Crocidura caudipilosa , which proved to be more closely related to the Temboan white-toothed shrew, possibly also to the small black-footed white-toothed shrew. There are probably various cryptic species hidden in the forms already known . Crocidura caudipilosa itself has only a small genetic range of variation and has therefore probably spread across the island in a relatively recent period. The Sulawesi group could have a closer relationship with the Java white-toothed shrew ( Crocidura maxi ).
The first scientific description of Crocidura caudipilosa took place in 2019 by Jacob A. Esselstyn and colleagues. The introduction of the new species was preceded by intensive field research that lasted almost a decade and in which data on the white-toothed shrews were collected in various places across Sulawesi. The holotype includes a male who was found in March 2013 on Mount Dako in central Sulawesi at an altitude of 513 m. The region forms the type area of the species. The species name caudipilosa is derived from the Latin word cauda for "tail" and the Greek word πιλος ( pilos ) for "hair". It thus refers to the thickly hairy tail.
literature
- Jacob A. Esselstyn, Anang S. Achmadi, Heru Handika, Thomas C. Giarla and Kevin C. Rowe: A new climbing shrew from Sulawesi highlights the tangled taxonomy of an endemic radiation. Journal of Mammalogy 100 (6), 2019, pp. 1713-1725, doi: 10.1093 / jmammal / gyz077
Individual evidence
- ↑ a b c d e f Jacob A. Esselstyn, Anang S. Achmadi, Heru Handika, Thomas C. Giarla and Kevin C. Rowe: A new climbing shrew from Sulawesi highlights the tangled taxonomy of an endemic radiation. Journal of Mammalogy 100 (6), 2019, pp. 1713-1725, doi: 10.1093 / jmammal / gyz077
- ↑ Sophie Quérouil, Rainer Hutterer, Patrick Barrière, Marc Colyn, Julian C. Kerbis Peterhans and Erik Verheyen: Phylogeny and Evolution of African Shrews (Mammalia: Soricidae) Inferred from 16s rRNA Sequences. Molecular Phylogenetics and Evolution 20 (2), 2001, pp. 185-195
- ↑ a b c Sylvain Dubey, Nicolas Salamin, Manuel Ruedi, Patrick Barrière, Marc Colynv and Peter Vogel: Biogeographic origin and radiation of the Old World crocidurine shrews (Mammalia: Soricidae) inferred from mitochondrial and nuclear genes. Molecular Phylogenetics and Evolution 48, 2008, pp. 953-963
- ^ Sylvain Dubey, Nicolas Salamin, Satoshi D. Ohdachi, Patrick Barrière, and Peter Vogel: Molecular phylogenetics of shrews (Mammalia: Soricidae) reveal timing of transcontinental colonizations. Molecular Phylogenetics and Evolution 44, 2007, pp. 126-137
- ^ CJ Burgin and K. He: Family Soricidae (shrews). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 332–551 ISBN 978-84-16728-08-4