Crocidura ramona

Shpirer, Erez, Haddas-Sasson, Michal, Spivak-Glater, Maya, Feldstein, Tamar, Meiri, Shai & Huchon, Dorothée, 2021, Molecular relationships of the Israeli shrews (Eulipotyphla: Soricidae) based on cytochrome b sequences, Mammalia (Warsaw, Poland) 85 (1), pp. 79-89 : 86

4.1 Crocidura ramona

Our work, based on sequences from type specimens, corroborates the view that C. ramona is a distinct species and probably endemic to Israel and the West Bank ( Dubey et al. 2008; Ivanitskaya et al. 1996). C. ramona has been suggested to be related to the Palearctic “flat-headed rockshrews” (i.e., Crocidura pergrisea , C.arispa , Crocidura armenica , Crocidura serezkyensis and C. zarudnyi ) ( Burgin et al. 2018b; Kry Š tufek and Vohralík 2001). Although the DNA of most of the latter has not yet been sequenced, our analysis indicates that C. ramona and C. zarudnyi are distantly related ( Figure 2 ). Similarly, we have shown here that C. ramona is not closely related to another silvery-gray shrew – C. nana , as the two formed two distinct and distant clades in our phylogenetic analyses (Supplementary Figure S1 ). We note that there is some doubt regarding C. nana ’s distribution. It is usually considered to be restricted to Somalia and Ethiopia ( Cassola 2019; Hutterer 2005), whereas the samples sequenced in this work originated from Tanzania. We cannot be certain therefore that C. nana is the correct species assignment for the Tanzanian samples that we sequenced.

Because no morphological comparisons have been carried out between the skulls of C. katinka and C. ramona , the exact relationship between these two species remains to be determined. Although C. katinka has been suggested to be related to certain African species with cranial similarities (e.g., Crocidura bottegi , C. obscurior , Crocidura bottegoides ) ( Burgin et al. 2018b; Hutterer and Kock 2002), our analyses have demonstrated that C. ramona is unrelated to C. obscurior .

It is also possible that C. ramona is conspecific with C. portali . Thomas (1920) described C. portali as a small shrew (“though not excessively so”), with “pale drab-grey” pelage; and indicated that it has “clearly nothing to do with the C. russula group”. The gross morphology of the holotype (BMNH #19.4.11.9) and its size agree with C. ramona – though a detailed examination is still needed in order to confirm or refute this. Kry Š tufek and Vohralík (2001) suggested that C. portali may be a valid species, related to Crocidura arispa (and other members of the pergrisea group), and a senior synonym of C. ramona . Hutterer and Kock (2002) indicated that C. ramona and C. portali are similar in skull dimensions as well as in pelage, but note that they are also similar to C. gmelini , a species that they note requires “a better definition”. C. gmelini (ranging from Iran to Mongolia) has been synonymized with C. suaveolens , a species distantly related to C. ramona ( Figure 2 ). C. arispa , C. ramona , and C. katinka are currently all considered valid species, while C. portali is not ( Burgin et al. 2018b; IUCN 2020). Clearly, a taxonomic revision of these taxa is warranted. Neither the DNA of the C. portali type, nor that of any shrews identified as C. arispa , C. pergrisea , or C. katinka , has been sequenced and, unfortunately, we failed to amplify any cyt b fragment from a tissue of a specimen identified as C. portali (BMNH ZD 1971.817). We thus tentatively ascribe the sequence we obtained to C. ramona , pending a taxonomic revision.

Figures

Figure 1: Shrew sample locations. A. samples sequenced in this work. B. shrew specimen present in the Steinhardt National Collection of Natural History, Zoological Museum at Tel Aviv University (Israel). The two major biomes of Israel: the Mediterranean biome, and the desert, are indicated in green and yellow,respectively. Red squares, blues stars, green circles and black triangles indicate C. ramona, S. etruscus, C. suaveolens gueldenstaedtii and C. leucodon specimen respectively.The museum records encompass 79 C. leucodon, 594 C. suaveolens gueldenstaedtii, 13 C. ramona and 443 S. etruscus.

Figure 2: Maximum likelihood tree of Crocidura cytb sequences with emphasis on the Asian and Old World species. Phylogenetic relationships inferred from a matrix of 1,128 nucleotide positions for 131 individuals. Maximum likelihood bootstrap supports above 50% and Bayesian posterior probabilities above 0.70 are indicated near the corresponding node separated with a slash. Sequences obtained in this work are indicated in bold. Authors of sequence data in Supplementary Table S3.