Distribution and Abundance of Manatees Along the Northern Coast of the Gulf of Mexico

A review of historical and recent records of manatee (Trichechus manatus) sightings along the coast of the northern Gulf of Mexico indicates that their numbers have declined in Texas, but increased in Louisiana and Mississippi. This is due to their extirpation in Mexico and dramatic increase along the southern Big Bend coast of northwestern peninsular Florida. The distribution of manatees along the southern Big Bend coast is related to their need for warm water and the distribution of fresh water and submerged aquatic and marine food plants. The spring-fed headwaters of Crystal and Homosassa rivers are important warm water winter refuges; nearly 90% of the same individuals return each winter. The estuaries and grass beds associated with these two rivers and the Suwannee, Withlacoochee, and Chasshowitzka rivers are the principal summer habitats. The Suwannee and Crystal rivers are high-use rivers, whereas the other three are low-use rivers. Low human-caused mortality, high fecundity, some immigration, and high site fidelity are responsible for the increasing numbers of manatees using the southern Big Bend coast. Since this region of Florida has experienced relatively little development compared with the rest of the state, the best long-term future for this endangered marine mammal in the United States lies along the southern Big Bend coast

Phylogeny and taxonomy of the round-eared sengis or elephant-shrews, genus Macroscelides (Mammalia, Afrotheria, Macroscelidea)

CITATION: Dumbacher, J. P., Rathbun, G. B., Smit, H. A. & Eiseb, S. J. 2012. Phylogeny and taxonomy of the round-eared sengis or elephant-shrews, genus Macroscelides (Mammalia, Afrotheria, Macroscelidea). PLoS ONE, 7(3):e32410, doi:10.1371/journal.pone.0032410.The original publication is available at http://journals.plos.org/plosoneThe round-eared sengis or elephant-shrews (genus Macroscelides) exhibit striking pelage variation throughout their ranges. Over ten taxonomic names have been proposed to describe this variation, but currently only two taxa are recognized (M. proboscideus proboscideus and M. p. flavicaudatus). Here, we review the taxonomic history of Macroscelides, and we use data on the geographic distribution, morphology, and mitochondrial DNA sequence to evaluate the current taxonomy. Our data support only two taxa that correspond to the currently recognized subspecies M. p. proboscideus and M. p. flavicaudatus. Mitochondrial haplotypes of these two taxa are reciprocally monophyletic with over 13% uncorrected sequence divergence between them. PCA analysis of 14 morphological characters (mostly cranial) grouped the two taxa into non-overlapping clusters, and body mass alone is a relatively reliable distinguishing character throughout much of Macroscelides range. Although fieldworkers were unable to find sympatric populations, the two taxa were found within 50 km of each other, and genetic analysis showed no evidence of gene flow. Based upon corroborating genetic data, morphological data, near sympatry with no evidence of gene flow, and differences in habitat use, we elevate these two forms to full species. © 2012 Dumbacher et al.http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0032410Publisher's versio

Phylogeny and Taxonomy of the Round-Eared Sengis or Elephant-Shrews, Genus Macroscelides (Mammalia, Afrotheria, Macroscelidea)

The round-eared sengis or elephant-shrews (genus Macroscelides) exhibit striking pelage variation throughout their ranges. Over ten taxonomic names have been proposed to describe this variation, but currently only two taxa are recognized (M. proboscideus proboscideus and M. p. flavicaudatus). Here, we review the taxonomic history of Macroscelides, and we use data on the geographic distribution, morphology, and mitochondrial DNA sequence to evaluate the current taxonomy. Our data support only two taxa that correspond to the currently recognized subspecies M. p. proboscideus and M. p. flavicaudatus. Mitochondrial haplotypes of these two taxa are reciprocally monophyletic with over 13% uncorrected sequence divergence between them. PCA analysis of 14 morphological characters (mostly cranial) grouped the two taxa into non-overlapping clusters, and body mass alone is a relatively reliable distinguishing character throughout much of Macroscelides range. Although fieldworkers were unable to find sympatric populations, the two taxa were found within 50 km of each other, and genetic analysis showed no evidence of gene flow. Based upon corroborating genetic data, morphological data, near sympatry with no evidence of gene flow, and differences in habitat use, we elevate these two forms to full species

The status of the world's land and marine mammals: diversity, threat, and knowledge

Knowledge of mammalian diversity is still surprisingly disparate, both regionally and taxonomically. Here, we present a comprehensive assessment of the conservation status and distribution of the world's mammals. Data, compiled by 1700+ experts, cover all 5487 species, including marine mammals. Global macroecological patterns are very different for land and marine species but suggest common mechanisms driving diversity and endemism across systems. Compared with land species, threat levels are higher among marine mammals, driven by different processes (accidental mortality and pollution, rather than habitat loss), and are spatially distinct (peaking in northern oceans, rather than in Southeast Asia). Marine mammals are also disproportionately poorly known. These data are made freely available to support further scientific developments and conservation action

Home range and use of diurnal shelters by the Etendeka round-eared sengi, a newly discovered Namibian endemic desert mammal

To understand habitat use by the newly described Etendeka round-eared sengi (Macroscelides micus) in northwestern Namibia, we radio-tracked five individuals for nearly a month. Home ranges (100% convex polygons) in the rocky desert habitat were remarkably large (mean 14.9 ha) when compared to sengi species in more mesic habitats (<1.5 ha). The activity pattern of M. micus was strictly nocturnal, which contrasts to the normal diurnal or crepuscular activity of other sengis. The day shelters of M. micus were under single rocks and they likely were occupied by single sengis. One tagged sengi used 22 different day shelters during the study. On average, only 7% of the day shelters were used more than once by the five tagged sengis. The shelters were also unusual for a small mammal in that they were unmodified in terms of excavation or nesting material. Shelter entrances were significantly oriented to face south by south west (average 193°), away from the angle of the prevailing midday sun. This suggests that solar radiation is probably an important aspect of M. micus thermal ecology, similar to other sengis. Compared to published data on other sengis, M. micus generally conforms to the unique sengi adaptive syndrome, but with modifications related to its hyper-arid habitat

Phylogeny and taxonomy of the round-eared sengis or elephant-shrews, genus Macroscelides (Mammalia, Afrotheria, Macroscelidea)

CITATION: Dumbacher, J. P., Rathbun, G. B., Smit, H. A. & Eiseb, S. J. 2012. Phylogeny and taxonomy of the round-eared sengis or elephant-shrews, genus Macroscelides (Mammalia, Afrotheria, Macroscelidea). PLoS ONE, 7(3):e32410, doi:10.1371/journal.pone.0032410.The original publication is available at http://journals.plos.org/plosoneThe round-eared sengis or elephant-shrews (genus Macroscelides) exhibit striking pelage variation throughout their ranges. Over ten taxonomic names have been proposed to describe this variation, but currently only two taxa are recognized (M. proboscideus proboscideus and M. p. flavicaudatus). Here, we review the taxonomic history of Macroscelides, and we use data on the geographic distribution, morphology, and mitochondrial DNA sequence to evaluate the current taxonomy. Our data support only two taxa that correspond to the currently recognized subspecies M. p. proboscideus and M. p. flavicaudatus. Mitochondrial haplotypes of these two taxa are reciprocally monophyletic with over 13% uncorrected sequence divergence between them. PCA analysis of 14 morphological characters (mostly cranial) grouped the two taxa into non-overlapping clusters, and body mass alone is a relatively reliable distinguishing character throughout much of Macroscelides range. Although fieldworkers were unable to find sympatric populations, the two taxa were found within 50 km of each other, and genetic analysis showed no evidence of gene flow. Based upon corroborating genetic data, morphological data, near sympatry with no evidence of gene flow, and differences in habitat use, we elevate these two forms to full species. © 2012 Dumbacher et al.http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0032410Publisher's versio

Late Pleistocene potential distribution of the North African sengi or elephant-shrew Elephantulus rozeti (Mammalia: Macroscelidea)

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 gen. nov., a new genus replacement for the North African sengi Elephantulus rozeti (Macroscelidea; Macroscelididae)

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: 10.11646/zootaxa.4136.3.

Petrosaltator Rathbun and Dumbacher, new genus

Petrosaltator Rathbun and Dumbacher, new genus Fig. 3 Type species: Petrosaltator rozeti (Duvernoy, 1833) Holotype. The type specimen is located at Musée 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 & Séguignes 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 (Séguignes 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/26565