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The Sahara Desert was recently proposed as the agent of vicariant speciation in the North African elephant-shrew (order Macroscelidea, Elephantulus rozeti). Based on evidence from molecular dating, however, this speciation event was estimated as having occurred in the Miocene, an early date of origin for an extant species, predating the dramatic climatic fluctuations of the Pleistocene. Here, we explore the possibility of more recent connections of populations of this species across the Sahara Desert that would have facilitated faunal exchange through the Last Glacial Maximum.We used ecological niche modelling based on current climatic datasets and known occurrence points to develop models of present-day potential distributions of E. rozeti and related taxa. Given that the Miocene scenario was proposed based on a single set of evidence, we here provide a partial test based on an independent analysis of present and past potential distributions. Our results corroborate the idea of vicariance, but indicate that distributional patterns and ecological characteristics are consistent with a more recent, post-Pleistocene vicariance across an increasingly arid Sahara. We emphasize the importance of multiple sets of evidence to be brought to bear on complex biogeographical questions, and offer models of palaeoclimatic and palaeoecological distributions and independent sources of such information to complement molecular systematic studies.African Zoology 45(2): 330–339 (October 2010)

Petrosaltator Rathbun and Dumbacher, new genus Fig. 3 Type species: Petrosaltator rozeti (Duvernoy, 1833) Holotype. The type specimen is located at Mus��e Zoologique de la ville de Strasbourg, France; specimen number MZSMAM03685. Geographic distribution. Petrosaltator has a unique range, and is currently the only species of the family Macroscelididae that occurs north of the Sahara Desert. It is known from the Maghreb Region of northern Africa, in Mediterranean, sub-desert, and montane zones from near sea level to 2725m elevation (Fig. 1) (Corbet & Hanks 1968; Cuzin & S��guignes 1990). Diagnosis and description. The genus Petrosaltator is monotypic (P. rozeti) (Corbet & Hanks 1968; Duvernoy 1833; Perrin & Rathbun 2013). Features that distinguish the genus from all other Macroscelidinae are rare (see below), thus explaining why it was included in Elephantulus by earlier workers. Genetic data are among the most useful diagnostic characters, and have been used here and elsewhere to identify P. rozeti and clearly align it with Petrodromus and Macroscelides (Douady et al. 2003; Kuntner et al. 2011; Smit et al. 2011). Petrosaltator measurements include head and body 90���130mm, tail 95���140mm, hind foot 29���37mm, upper tooth row 16���19mm, with larger individuals from north of the Atlas mountains belonging to the nominate forms, P. r. rozeti, and smaller individuals south of the Atlas mountains belonging to P. r. deserti (Corbet & Hanks 1968). Despite overall morphological similarity, Petrosaltator differs from Elephantulus in the following characters. In penis morphology, Petrosaltator has two lateral lobes and a tapering distal end, whereas Elephantulus species have a bulbous tip of the glans penis (Woodall 1995 b). In superficial male mammary morphology, Petrosaltator males have small nipples which are absent in Elephantulus (Olbricht & Stanley 2009). Finally, Petrosaltator has an ossified stapediofacial tube that corresponds to the bony enclosure of the path of the facial nerve within the bulla (Benoit et al. 2013). Corbet & Hanks (1968) additionally identify three morphological characters that distinguish Petrosaltator from Elephantulus (see Corbet & Hanks 1968, Table 1, page 49). Character states shared by Petrosaltator and Macroscelides include a large tragus and highly rugose interdigital pads (Corbet & Hanks 1968). Synapomorphies of Petrosaltator and Petrodromus include the double root on the third upper incisor (I 3). Corbet & Hanks (1968, Table 1) identify no single morphological character that has a unique character state in Petrosaltator rozeti (Corbet & Hanks 1968). Petrosaltator can additionally be distinguished from Macroscelides in having significantly smaller mastoids and auditory bullae, smaller supratragus, and slightly less-silky pelage (Corbet & Hanks 1968). Petrosaltator differs from Petrodromus in being smaller overall, having the hallux present, having three rows of mammae (vs. two in Petrodromus), and having no facial markings (vs. Petrodromus having a prominent dark spot behind the eye), having caudal hair on distal dorsal tail surface (dorsal tail surface is essentially naked in Petrodromus), and the eye and pinnae are proportionally smaller in Petrosaltator in comparison to overall head size, Etymology. The roots of Petrosaltator (masculine gender) are Greek (petro) and Latin (saltator), together meaning ���rockdancer���. This genus name reflects the habitats occupied by this species, which are dominated by rocks and boulders (S��guignes 1988). Petrosaltator also alludes to the phylogenetic relationship with Petrodromus (meaning rockrunner with Greek roots), although oddly Petrodromus tetradactylus is not specifically a petrophile (Jennings & Rathbun 2001). We suggest that the common name of Petrosaltator rozeti continue to be the North African Sengi or Elephant-shrew. Specimens examined. Our work is based primarily on molecular analyses, and specimens sequenced are listed in Table 1. The two P. rozeti specimens sequenced were P. rozeti rozeti (CASMAM 27982 from north of the Atlas Mountains) and P. r. deserti [from Douady et al. (Douady et al. 2003), south of the Atlas Mountains]. Based on the divergence level between these two specimens (Fig. 2, uncorrected p-distance at 12 s��� 16 s rDNA = 1.09 % divergence), recognizing two subspecies of P. rozeti could be justified, although the lack of morphometrics, our minimal sample size, and analysis of only one genetic region precludes any definitive determination., Published as part of Dumbacher, John P., Carlen, Elizabeth J. & Rathbun, Galen B., 2016, Petrosaltator gen. nov., a new genus replacement for the North African sengi Elephantulus rozeti (Macroscelidea; Macroscelididae), pp. 567-579 in Zootaxa 4136 (3) on page 574, DOI: 10.11646/zootaxa.4136.3.8, http://zenodo.org/record/265656, {"references":["Duvernoy, G. L. (1833) Description d'un Macroscelide d'Alger. Memoires de la Societe d'Histoire Naturelle de Strasbourg, 1, 1 - 25.","Corbet, G. B. & Hanks, J. (1968) A revision of the elephant-shrews, Family Macroscelididae. Bulletin of the British Museum (Natural History) Zoology, 16, 47 - 111.","Cuzin, F. & Seguignes, M. (1990) Capture d' Elephantulus rozeti (Macroscelidae, Macroscelididae) dans le Haut-Atlas marocain au dessus de 2700 m. Mammalia, 54, 164 - 165.","Perrin, M. & Rathbun, G. B. (2013) Species accounts: Order Macroscelidea, Family Macroscelididae, Genus Elephantulus, E. edwardii, E. intufi, E. myurus, E. rozeti, E. rufescens; Genus Macroscelides; species account M. proboscideus. In: Kingdon, J., Happld, D., Hoffmann, M., Butynski, T., Happold, M. & Kalina, J. (Eds.), Mammals of Africa. Vol. I. Bloombury, London, pp. 261 - 278.","Douady, C. J., Catzeflis, F., Raman, J., Springer, M. S. & Stanhope, M. J. (2003) The Sahara as a vicariant agent, and the role of Miocene climatic events, in the diversification of the mammalian order Macroscelidea (elephant shrews). Proceedings of the National Academy of Sciences USA, 100, 8325 - 8330. http: // dx. doi. org / 10.1073 / pnas. 0832467100","Kuntner, M., May-Collado, L. J. & Agnarsson, I. (2011) Phylogeny and conservation priorities of afrotherian mammals (Afrotheria, Mammalia). Zoologica Scripta, 40, 1 - 15. http: // dx. doi. org / 10.1111 / j. 1463 - 6409.2010.00452. x","Smit, H. A., Van Vuuren, B. J., O'Brian, P. C. M., Ferguson-Smith, M. A., Yang, F. & Robinson, T. J. (2011) Phylogenetic relationships of elephant-shrews (Afrotheria, Macroscelididae). Journal of Zoology, London, 284, 133 - 143. http: // dx. doi. org / 10.1111 / j. 1469 - 7998.2011.00790. x","Woodall, P. F. (1995 b) The penis of elephant shrews (Mammalia: Macroscelididae). Journal of Zoology, London, 237, 399 - 410. http: // dx. doi. org / 10.1111 / j. 1469 - 7998.1995. tb 02770. x","Olbricht, G. & Stanley, W. T. (2009) The topographic distribution of the penis and mammary glands in sengis (Macroscelidea) and its usefulness for taxonomic distinctions. Zoosystematics and Evolution, 85, 297 - 303. http: // dx. doi. org / 10.1002 / zoos. 200900007","Benoit, J., Crumpton, N., Merigeaud, S. & Tabuce, R. (2013) Petrosal and bony labyrinth morphology supports paraphyly of Elephantulus within Macroscelididae (Mammalia, Afrotheria). Journal Mammalian Evolution, 21, 173 - 193. http: // dx. doi. org / 10.1007 / s 10914 - 013 - 9234 - 5","Seguignes, M. (1988) Facteurs de repartition d ' Elephantulus rozeti (Macroscelidea, Macroscelididae) en Afrique du nord. In: Academie de Montpellier. Universite des Sciences et Techniques du Languedoc, Montpellier, pp. 326","Jennings, M. R. & Rathbun, G. B. (2001) Petrodromus tetradactylus. American Society of Mammalogists, Mammalian Species, 682, 1 - 6. http: // dx. doi. org / 10.1644 / 1545 - 1410 (2001) 682 % 3 C 0001: PT % 3 E 2.0. CO; 2"]}

Dumbacher, John P., Carlen, Elizabeth J., Rathbun, Galen B. (2016): Petrosaltator gen. nov., a new genus replacement for the North African sengi Elephantulus rozeti (Macroscelidea; Macroscelididae). Zootaxa 4136 (3): 567-579, DOI: http://doi.org/10.11646/zootaxa.4136.3.8