Crocidura attenuata Milne-Edwards, 1872

Abramov, Alexei V., Bannikova, Anna A. & Rozhnov, Viatcheslav V., 2012, White-toothed shrews (Mammalia, Soricomorpha, Crocidura) of coastal islands of Vietnam, ZooKeys 207, pp. 37-47 : 41-43

Crocidura attenuata Milne-Edwards, 1872

We collected seven specimens of this species from Cat Ba Island. The trapping line (20°48'N, 106°59'E) was located along the west part of tourist trail from the Cat Ba National Park Headquarters to Viet Hai Village. All specimens were caught in pitfall traps set in mixed forest near limestone bare rocks. It is the first record of Crocidura from Cat Ba Island.

This is a medium-sized Crocidura , with a moderately long tail; tail 79.8% of head and body length, in average. Means and extremes of measurements (in mm) from 5 adults are: head and body length, 74.6 (71-79); tail length, 59.2 (57-62); hind foot length, 13.2 (12-14); weight (n=4), 9.8 (7.3-11.5) g.

Analysis of mitochondrial DNA confirmed that the specimens from Cat Ba belong to Crocidura attenuata proper. All the analyzed specimens from Cat Ba (see Fig. 2) formed a single cluster closely related to the group of specimens from northern Vietnam (Ha Giang Province) and southeastern China (Guangxi Province). The genetic distance (p-distance) between specimens from Cat Ba/Ha Giang as well as Cat Ba/Guangxi is about 2.1%. The specimen of Crocidura attenuata from the more north-eastern region of China (Hunan Province) appears basal among all samples of Crocidura attenuata from China and Vietnam. Thus, the genetic distance between two specimens from China (Hunan/Guangxi) is 4.3%, which is nearly the same as the distance between Crocidura indochinensis / Crocidura sp. AB1. Thus, genetic differentiation of Crocidura attenuata is notable and reveals a phylogeographic structure with four haplogroups.

Most authors ( Heaney and Timm 1983; Huynh et al. 1994; Hutterer 2005; Kuznetsov 2006; Can et al. 2008; Jenkins et al. 2009) have suggested a wide geo graphic distribution for Crocidura attenuata in Vietnam. However, the recent study of mitochondrial DNA ( Bannikova et al. 2011) restricted the distribution of Crocidura attenuata proper to the northernmost part of Vietnam. Elsewhere in mainland Vietnam, it is replaced by Crocidura tanakae . The latter species was previously considered an endemic of Taiwan ( Motokawa et al. 1997, 2001; Hutterer 2005). However, based on mtDNA data analyses, the name Crocidura tanakae has been applied to all white-toothed shrews that are genetically similar to the Taiwanese haplogroup. This haplogroup is widely distributed across mainland Asia, including in southern China, Vietnam and Laos ( Esselstyn et al. 2009, 2010; Bannikova et al. 2011).

Documentation of Crocidura attenuata on Cat Ba Island well corresponds to the proposed species’ distribution confined to the north and east of the Red River (see Bannikova et al. 2011).