Cryptotis nigrescens
Creators: name: Mittermeier, Russell A.
name: Wilson, Don E.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Soricomorpha
Soricidae
Cryptotis
Cryptotis nigrescens

description: 96. Blackish Small-eared Shrew <i>Cryptotis nigrescens</i> <b>French:</b> Musaraigne noire / <b>German:</b> Schwarzliche Kleinohrspitzmaus / <b>Spanish:</b> Musarana de orejas pequenas negruzca <b>Taxonomy.</b> Blarina (Soriciscus) nigrescens J. A. Allen, 1895, “ San Isidro (San José [Province]), Costa Rica.” Cryptotis nigrescens is in the C. nigrescens group and previously included many of the currently recognized species of Neotropical Cryptotis as synonyms or subspecies. A. B. Baird and colleagues in 2018 found that C. nigrescens was basal to the rest of the sequenced species in the C. nigrescens group (C. lacandonensis, C. mayen- sis, and a paraphyletic C. merriami) and determined that the C. nigrescens group was sister to a clade including the C. parvus group, C. goldmani group, and C. goodwini group, with the C. mexicanus group being the most basal lineage in Cryplotis. The C. nigrescens group also includes C. brachyonyx, C. colombianus, C. hondurensis, C. merus, C. lacandonensis, C. mayensis, and C. merriami, but in another recent study by H. Zeballos and colleagues in 2018, C. niausa was sister to the C. nigrescens group even though it was morphologically in the C. thomas: group. In the same study, the C. thomasi group was sister to the C. nigrescens group, although additional sampling from all species in both groupsis needed to clarify these relationships. Monotypic. <b>Distribution.</b> Highlands of Costa Rica and W Panama. <b>Descriptive notes.</b> Head-body 55-83 mm, tail 19-37 mm, hindfoot 13-14 mm; weight 5-8 g. The Blackish Small-eared Shrew is mid-sized to large, with relatively short and broad snout. Dorsum is dark brownish black, occasionally sprinkled with paler hairs, and venter is slightly paler charcoal gray. Feet are small and slim, with tiny claws, and dusky in color. Tail is short (c.40% of head-body length), covered with short hair, and blackish. Eyes are diminutive, and ears are small and barely visible under fur. Typical of the C. nigrescens group, anterior border of coronoid process joins horizontal ramus of mandible at high angle, anterior element of ectoloph of M' is about equal in size to posterior element, and unicuspids are typically large in lateral view of skull, with straight or convex postero-ventral margins. Teeth are reddish, and there are four unicuspids. <b>Habitat.</b> Cool evergreen forests, forest edges, and occasionally drier open woodlands on the Pacific slopes at elevations of 800-2900 m (above 800 m in Costa Rica and above 1000 m in Panama). In some areas, the Blackish Small-eared Shrew is found in pastures and other open areas. <b>Food and Feeding.</b> Probably insectivorous. <b>Breeding.</b> Litters of the Blackish Small-eared Shrew have 1-3 young. <b>Activity patterns.</b> Probably nocturnal and a strong digger. <b>Movements, Home range and Social organization.</b> No information. <b>Status and Conservation.</b> Classified as Least Concern on The IUCN Red List. The Blackish Small-eared Shrew is apparently common and found in multiple protected areas with no major threats, although its distribution is relatively small and very little is known ofits natural history. <b>Bibliography.</b> Baird et al. (2018), Choate (1970), Guevara &amp; Cervantes (2014), He et al. (2015), Hutterer (2005b), Moreno (2017), Naylor &amp; Roach (2016¢), Reid (2009), Woodman (2011a, 2011b), Woodman &amp; Gaffney (2014), Woodman &amp; Morgan (2005), Woodman &amp; Péfaur (2008), Woodman &amp; Timm (1993), Zeballos et al. (2018).
description: Published as part of <i>Russell A. Mittermeier &amp; Don E. Wilson, 2018, Soricidae, pp. 332-551 in Handbook of the Mammals of the World – Volume 8 Insectivores, Sloths and Colugos, Barcelona :Lynx Edicions</i> on pages 429-430, DOI: 10.5281/zenodo.6870843