A new species of small-eared shrew (Mammalia, Eulipotyphla,Cryptotis) from the Lacandona rain forest, Mexico

Abstract

The diversity and distribution of mammals in the American tropics remain incompletely known. We describe a new species of small-eared shrew (Soricidae, Cryptotis) from the Lacandona rain forest, Chiapas, southern Mexico. The new species is distinguished from other species of Cryptotis on the basis of a unique combination of pelage coloration, size, dental, cranial, postcranial, and external characters, and genetic distances. It appears most closely related to species in the Cryptotis nigrescens species group, which occurs from southern Mexico to montane regions of Colombia. This discovery is particularly remarkable because the new species is from a lowelevation habitat (approximately 90 m), whereas most shrews in the region are restricted to higher elevations, typically . 1,000 m. The only known locality for the new shrew is in one of the last areas in southern Mexico where relatively undisturbed tropical vegetation is still found. The type locality is protected by the Mexican government as part of the Yaxchilán Archaeological Site on the border between Mexico and Guatemala.

First record of the shrew Cryptotis lacandonensis (Eulipotyphla: Soricidae) for Guatemala

“…These specimens are deposited in two collections: Universidad de San Carlos de Guatemala (USAC) and Museo de Historia Natural, Ciudad Universitaria, Universidad Nacional Autónoma de Honduras (UNAH-CU); a complete list of specimens examined and their localities is given in the forward section. We were not able to check directly the holotype and paratype of C. lacandonensis, as it is desired in this comparisons, but since it was one of the probable names for the Bethel specimen, due to the proximity to the type locality, we included in the morphometric analysis the measurements of the holotype and paratype reported in Guevara et al (2014).…”

“…We also confirmed normality of all variables. Both PCA and LDA included 23 individuals in total (Bethel specimen plus 20 specimens examined and two type specimens reported in Guevara et al (2014).…”

“…The small-eared short tailed shrews of the genus Cryptotis occur from southern Canada, through the United States, México and Central America, to northwestern South America (Choate 1970). There are at least 42 known species in four species-groups based on morphological and molecular characters (He et al 2015;Hutterer 2005;Guevara et al 2014), but their taxonomy still remains subject to many changes. Three groups and seven species are known for Guatemala: C. goodwini, C. lacertosus, C. mam, C. oreoryctes, C. tropicalis, C. mayensis, C. merriami (Hutterer 2005;Carraway 2007;Woodman 2010).…”

“…The C. nigrescens group includes seven tropical and mountain species from México to the Andes, but only two are known for Guatemala: C. mayensis and C. merriami (Woodman and Timm 1993). Recently Guevara et al (2014) described C. lacandonensis, a lowland short-tailed shrew of the C. nigrescens group, from the Lacandona rain forest at Yaxchilán archaelogical site, in Chiapas, México (Figure 1). C. lacandonensis is the sister species of C. mayensis, based on molecular information (Guevara et al 2014, He et al 2015, and they are the only two species known to occur in the lowlands of the Yucatan Peninsula in México, the Petén in Guatemala, and Belize.…”

“…Recently Guevara et al (2014) described C. lacandonensis, a lowland short-tailed shrew of the C. nigrescens group, from the Lacandona rain forest at Yaxchilán archaelogical site, in Chiapas, México (Figure 1). C. lacandonensis is the sister species of C. mayensis, based on molecular information (Guevara et al 2014, He et al 2015, and they are the only two species known to occur in the lowlands of the Yucatan Peninsula in México, the Petén in Guatemala, and Belize. C. mayensis is widely distributed in the Yucatán Peninsula, while C. lacandonensis is currently known only from the type locality, on the eastern and Mexican shore of the Usumacinta River.…”