African Shrews Research Articles

Palaeoclimatic niche modelling reveals the phylogeographic history of the South African shrew Myosorex varius and the colonisation route of the genus Myosorex (Mammalia, Soricidae) from East Africa

Myosorex varius is a South African generalist shrew, which has been found to consist of several genetic clades across its range. A northern clade inhabits the more mesic, summer-rainfall areas of grassland and savannah in the east of South Africa. A southern clade occupies areas of fynbos in the south, and can be further divided into a western subclade occupying winter-rainfall areas and an eastern subclade occupying areas with aseasonal rainfall. Non-South-African members of the African genus Myosorex primarily are limited to isolated montane habitats along the East African Rift System. Here, we used palaeoclimatic niche modelling to examine the effects of Pliocene and Pleistocene climate change on the distributions of M. varius, its clades and the genus as a whole. Results indicate that repeated cycles of range expansion during glacial periods and fragmentation during interglacials are responsible for current phylogeographic patterns within M. varius. Based on their close alignment with rainfall zones and lack of genetic mixing despite areas of contact, it is likely that these (sub)clades are locally adapted to their respective areas. Earlier climatic fluctuations allowed the genus to ‘island hop’ south from East Africa along the East African Rift System, expanding in range during cooler periods and retreating to montane refugia during warmer periods. Areas currently occupied by Myosorex species largely correspond with predicted montane refugia that have allowed them to survive previous warm periods.

Pathogenic Leptospira in Commensal Small Mammals from the Extensively Urbanized Coastal Benin

Leptospirosis is caused by spirochete bacteria of the genus Leptospira that affect one million and kill 60,000 persons annually in the world, who get infected through environmental mammal-excreted (notably rodent) pathogens. Using qPCR and DNA sequencing approaches, we here examine Leptospira occurrence and diversity in 971 commensal small mammals in urban and peri-urban habitats from south Benin, where socio-environmental conditions are favorable for human contamination. Prevalence reached 12.9% on average, but showed very important variations in both space and time, thus pointing toward a role of local processes in the maintenance and circulation of rodent-borne leptospires in the area. Prevalence peaks may occur during or one month after moderate (100–200 mm) monthly rainfall, suggesting that rodent-borne leptospires may be more prevalent when standing waters are present, but not at their highest levels (i.e., floods). However, this pattern will have to be confirmed through proper diachronic analysis. Finally, an incomplete but significant host-specificity was observed, with L. kirschneri retrieved only in African shrews, and the invasive Rattus norvegicus and the native Mastomys natalensis preferentially infected by L. interrogans and L. borgpeterseni, respectively. Our study highlights the urgent need for investigations on human leptospirosis in the extensively urbanized Abidjan–Lagos corridor.

Highly diversified shrew hepatitis B viruses corroborate ancient origins and divergent infection patterns of mammalian hepadnaviruses

Shrews, insectivorous small mammals, pertain to an ancient mammalian order. We screened 693 European and African shrews for hepatitis B virus (HBV) homologs to elucidate the enigmatic genealogy of HBV. Shrews host HBVs at low prevalence (2.5%) across a broad geographic and host range. The phylogenetically divergent shrew HBVs comprise separate species termed crowned shrew HBV (CSHBV) and musk shrew HBV (MSHBV), each containing distinct genotypes. Recombination events across host orders, evolutionary reconstructions, and antigenic divergence of shrew HBVs corroborated ancient origins of mammalian HBVs dating back about 80 million years. Resurrected CSHBV replicated in human hepatoma cells, but human- and tupaia-derived primary hepatocytes were resistant to hepatitis D viruses pseudotyped with CSHBV surface proteins. Functional characterization of the shrew sodium taurocholate cotransporting polypeptide (Ntcp), CSHBV/MSHBV surface peptide binding patterns, and infection experiments revealed lack of Ntcp-mediated entry of shrew HBV. Contrastingly, HBV entry was enabled by the shrew Ntcp. Shrew HBVs universally showed mutations in their genomic preCore domains impeding hepatitis B e antigen (HBeAg) production and resembling those observed in HBeAg-negative human HBV. Deep sequencing and in situ hybridization suggest that HBeAg-negative shrew HBVs cause intense hepatotropic monoinfections and low within-host genomic heterogeneity. Geographical clustering and low MSHBV/CSHBV-specific seroprevalence suggest focal transmission and high virulence of shrew HBVs. HBeAg negativity is thus an ancient HBV infection pattern, whereas Ntcp usage for entry is not evolutionarily conserved. Shrew infection models relying on CSHBV/MSHBV revertants and human HBV will allow comparative assessments of HBeAg-mediated HBV pathogenesis, entry, and species barriers.

Molecular taxonomy of Crocidura species (Eulipotyphla: Soricidae) in a key biogeographical region for African shrews, Nigeria

The taxonomy of African shrew species is still unresolved due to their conserved morphology. This also affects knowledge concerning their geographic distribution. In Nigeria, using mitochondrial Cytochrome b gene sequences, we carried out a survey for shrews from the genus Crocidura across various ecological zones to determine taxa that are present and also to assess their phylogeographic structure. Our analyses include 183 specimens collected with Sherman traps from 19 localities around the country. We detected six taxa: Crocidura olivieri lineages II, III and IV, C. hildegardeae, C. jouvenetae, and C. foxi. Among these, C. hildegardeae and C. jouvenetae are reported in Nigeria for the first time. Phylogenetic comparison of our genetic sequences to those generated from other parts of Africa demonstrate that all species in our study, as currently defined, are in need of taxonomic revision. Geographically, Nigeria seems to represent the easternmost boundary for C. olivieri lineage II and C. jouvenetae, and the western distribution limit of C. olivieri lineage IV and C. hildegardeae. The Niger River appears to be the most significant topographical barrier restricting these taxa. This information is vital to preserving the diversity but also managing the epidemiological potential of these small mammals.

Review of the fur-mite genus Soricilichus Fain, 1970 (Acariformes: Chirodiscidae)-symbionts of the African shrews of the subfamily Crocidurinae (Soricomorpha: Soricidae).

The fur-mite genus Soricilichus Fain, 1970 (3 species) (Acariformes: Chirodiscidae) represented by permanent symbionts of the African shrews of the subfamily Crocidurinae (Soricomorpha: Soricidae) is revised. The external morphology of these species was investigated with light and scanning electron microscopy. Based on the type specimens and newly obtained samples, 2 recognized species, S. scutisorex Fain, 1970 from Scutisorex somereni Thomas and S. kivuensis Fain, 1981 from Crocidura sp.-both are from DR of Congo-are redescribed. A new species S. sylvisorex sp. nov. found on shrews of the genera Sylvisorex (S. granti Thomas (type host), S. lunaris Thomas, S. vulcanorum Hutterer and Verheyen) and Crocidura (C. denti Dollman, C. cf. niobe, Crocidura sp.), collected in the DR Congo is also described. An amended generic diagnosis, including description of female immature stages, and a key to species are provided.

Lartetium africanum (Lavocat, 1961) (Eulipotyphla · Soricidae) from Beni-Mellal (Morocco), the oldest African shrew: new descriptions, palaeoenvironment and comments on biochronological context

Additional specimens of the poorly known African shrew Lartetium africanum (Lavocat, 1961) are described and complete our knowledge of this tiny animal. The results of this study justify the elevation of material originally described as a subspecies to the species rank. Soricids are hitherto unknown in older African localities. Like many other soricids, L. africanum lived in a rather humid habitat, close to a body of freshwater, as testified by the intercalations of travertines with reeds in the lacustrine lenses that yielded the fauna. However, the presence of associated vertebrate taxa also attest to more open environments in the surroundings and a tropical climate. Various hypotheses on the date of arrival of this taxon in Africa have been proposed since migration routes between Eurasia and Afro-Arabia were not always open during the Middle Miocene and also because magnetostratigraphic data are now known and can be compared. These hypotheses are discussed here. Recent advances in our knowledge of the palaeogeography and the comparison of L. africanum with western European Lartetium taxa suggest that Beni-Mellal could be older than previously proposed, possibly early Middle Miocene.

Phylogeography and evolutionary history of the Crocidura olivieri complex (Mammalia, Soricomorpha): from a forest origin to broad ecological expansion across Africa.

BackgroundThis study aims to reconstruct the evolutionary history of African shrews referred to the Crocidura olivieri complex. We tested the respective role of forest retraction/expansion during the Pleistocene, rivers (allopatric models), ecological gradients (parapatric model) and anthropogenic factors in explaining the distribution and diversification within this species complex. We sequenced three mitochondrial and four nuclear markers from 565 specimens encompassing the known distribution of the complex, i.e. from Morocco to Egypt and south to Mozambique. We used Bayesian phylogenetic inference, genetic structure analyses and divergence time estimates to assess the phylogenetic relationships and evolutionary history of these animals.ResultsThe C. olivieri complex (currently composed of C. olivieri, C. fulvastra, C. viaria and C. goliath) can be segregated into eight principal geographical clades, most exhibiting parapatric distributions. A decrease in genetic diversity was observed between central and western African clades and a marked signal of population expansion was detected for a broadly distributed clade occurring across central and eastern Africa and portions of Egypt (clade IV). The main cladogenesis events occurred within the complex between 1.37 and 0.48 Ma. Crocidura olivieri sensu stricto appears polyphyletic and C. viaria and C. fulvastra were not found to be monophyletic.ConclusionsClimatic oscillations over the Pleistocene probably played a major role in shaping the genetic diversity within this species complex. Different factors can explain their diversification, including Pleistocene forest refuges, riverine barriers and differentiation along environmental gradients. The earliest postulated members of the complex originated in central/eastern Africa and the first radiations took place in rain forests of the Congo Basin. A dramatic shift in the ecological requirements in early members of the complex, in association with changing environments, took place sometime after 1.13 Ma. Some lineages then colonized a substantial portion of the African continent, including a variety of savannah and forest habitats. The low genetic divergence of certain populations, some in isolated localities, can be explained by their synanthropic habits. This study underlines the need to revise the taxonomy of the C. olivieri complex.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-015-0344-y) contains supplementary material, which is available to authorized users.

Variation in the myosoricine hand skeleton and its implications for locomotory behavior (Eulipotyphla: Soricidae)

Substrate use and locomotory behavior of mammals are typically reflected in external characteristics of the forefeet, such as the relative proportions of the digits and claws. Although skeletal anatomy of the forefeet can be more informative than external characters, skeletons remain rare in systematic collections. This is particularly true for the Myosoricinae (Eulipotyphla: Soricidae), a small clade of African shrews that includes both ambulatory forest shrews (Myosorex) and semifossorial mole shrews (Surdisorex). Most species in this subfamily have restricted distributions, and their behavior and ecology are mostly unstudied. To better understand the potential range of locomotory behavior among myosoricines, we used digital x-rays to image and facilitate measuring the forefoot skeletons of 9 species. As a gauge of potential variation, we compared them with the ambulatory talpid Uropsilus (Talpidae) and the semifossorial talpid Neurotrichus. The hand morphologies of myosoricines show a graded range of potential substrate use between ambulatory and semifossorial. Some of these shrews exhibit adaptations for increased burrowing efficiency that are similar to those seen in talpids and other mammals, such as longer, broader distal phalanges and claws and shorter, wider metacarpals and proximal and middle phalanges. They also, however, have characteristics that are distinct from talpids, such as maintenance of forefoot asymmetry and an increased emphasis of ray III.

Cryptic diversity in forest shrews of the genus <italic>Myosorex</italic> from southern Africa, with the description of a new species and comments on <italic>Myosorex tenuis</italic>

Forest or mouse shrews (Myosorex) represent a small but important radiation of African shrews generally adapted to montane and/or temperate conditions. The status of populations from Zimbabwe, Mozambique, and the north of South Africa has long been unclear because of the variability of traits that have traditionally been ‘diagnostic’ for the currently recognized South African taxa. We report molecular (mitochondrial DNA and nuclear DNA), craniometric, and morphological data from newly collected series of Myosorex from Zimbabwe (East Highlands), Mozambique (Mount Gorogonsa, Gorongosa National Park), and the Limpopo Province of South Africa (Soutpansberg Range) in the context of the available museum collections from southern and eastern Africa and published DNA sequences. Molecular data demonstrate close genetic similarity between populations from Mozambique and Zimbabwe, and this well-supported clade (herein described as a new species, Myosorex meesteri sp. nov.) is the sister group of all South African taxa, except for Myosorex longicaudatus Meester & Dippenaar, 1978. Populations of Myosorex in Limpopo Province (herein tentatively assigned to Myosorex cf. tenuis) are cladistically distinct from both Myosorex varius (Smuts, 1832) and Myosorex cafer (Sundevall, 1846), and diverged from M. varius at approximately the same time (2.7 Mya) as M. cafer and Myosorex sclateri Thomas & Schwann, 1905 diverged (2.4 Mya). Morphometric data are mostly discordant with the molecular data. For example, clearly distinct molecular clades overlap considerably in craniometric variables. On the other hand, extreme size differentiation occurs between genetically closely related populations in the Soutpansberg Range, which coincides with the bissection of the mountain range by the dry Sand River Valley, indicating the potential for strong intraspecific phenotypic divergence in these shrews. © 2013 The Linnean Society of London

Cryptic diversity in forest shrews of the genusMyosorexfrom southern Africa, with the description of a new species and comments onMyosorex tenuis

Forest or mouse shrews (Myosorex) represent a small but important radiation of African shrews generally adapted to montane and/or temperate conditions. The status of populations from Zimbabwe, Mozambique, and the north of South Africa has long been unclear because of the variability of traits that have traditionally been ‘diagnostic’ for the currently recognized South African taxa. We report molecular (mitochondrial DNA and nuclear DNA), craniometric, and morphological data from newly collected series of Myosorex from Zimbabwe (East Highlands), Mozambique (Mount Gorogonsa, Gorongosa National Park), and the Limpopo Province of South Africa (Soutpansberg Range) in the context of the available museum collections from southern and eastern Africa and published DNA sequences. Molecular data demonstrate close genetic similarity between populations from Mozambique and Zimbabwe, and this well-supported clade (herein described as a new species, Myosorex meesteri sp. nov.) is the sister group of all South African taxa, except for Myosorex longicaudatus Meester & Dippenaar, 1978. Populations of Myosorex in Limpopo Province (herein tentatively assigned to Myosorex cf. tenuis) are cladistically distinct from both Myosorex varius (Smuts, 1832) and Myosorex cafer (Sundevall, 1846), and diverged from M. varius at approximately the same time (2.7 Mya) as M. cafer and Myosorex sclateri Thomas & Schwann, 1905 diverged (2.4 Mya). Morphometric data are mostly discordant with the molecular data. For example, clearly distinct molecular clades overlap considerably in craniometric variables. On the other hand, extreme size differentiation occurs between genetically closely related populations in the Soutpansberg Range, which coincides with the bissection of the mountain range by the dry Sand River Valley, indicating the potential for strong intraspecific phenotypic divergence in these shrews. © 2013 The Linnean Society of London

Genetic identity of the critically endangered Wimmer's shrewCrocidura wimmeri

Coastal primary rainforests have suffered damage in Cote d'Ivoire as a result of a lack of protection and urban pressures. Consequently, the highly endemic and critically endangered Wimmer's shrew, Crocidura wimmeri, known only from its type locality, Adiopodoume, near Abidjan, was considered to have been extinct since 1976. Shrew species assignment is often problematic because of strong phenotypic similarities among many species. The phylogenetic position of C. wimmeri within the African Crocidura species should thus be clarified. In light of its recent rediscovery in the nearby small Banco National Park (34 km2), we investigated the genetic identity of seven specimens of C. wimmeri, based on 1020 bp of the mitochondrial DNA cytochrome b gene compared to other species sampled in the same region and published sequences from GenBank. Crocidura wimmeri formed a well-defined clade, the closest-related species being Crocidura sp., with a distance of 9.3%, a yet unknown species from Tai and Ziama forests. These results thus confirmed the validity of this species. This genetic characterization not only contributes to our knowledge of the evolution of West African shrews, but also may help in the discovery of additional populations of this critically endangered species. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111, 224–229.

Complete genome sequence and molecular phylogeny of a newfound hantavirus harbored by the Doucet’s musk shrew (Crocidura douceti) in Guinea

Elucidation of the molecular phylogeny of shrew-borne hantaviruses in sub-Saharan Africa has been hampered by the lack of full-length viral genomes. In this report, we present the complete genome analysis of a newfound hantavirus, designated Bowé virus, detected in ethanol-fixed intercostal muscle of a Doucet’s musk shrew (Crocidura douceti), captured in southwestern Guinea in February 2012. Full-length amino acid sequence comparison of the S-, M- and L-segment gene products revealed that Bowé virus differed by 24.1-53.4%, 17.0-59.9% and 14.6-39.7%, respectively, from all other representative rodent-, shrew- and mole-borne hantaviruses. Phylogenetic analysis, using maximum-likelihood and Bayesian methods, under the GTR+I+Γ model of evolution, showed that Bowé virus shared a common ancestry with Tanganya virus, a hantavirus detected in the Therese’s shrew (Crocidura theresae) in Guinea. Whole genome analysis of many more hantaviruses from sub-Saharan Africa are needed to better clarify how the radiation of African shrews might have contributed to the phylogeography of hantaviruses.

Description and phylogenetic relationships of Rodentolepis gnoskei n. sp. (Cyclophyllidea: Hymenolepididae) from a shrew Suncus varilla minor in Malawi

Rodentolepis gnoskei n. sp. is described based on specimens obtained from a lesser dwarf shrew Suncus varilla minor collected in the Nyika National Park, Malawi. The new species is one of the smallest hymenolepidids known from African shrews and is morphologically closest to two other miniature hymenolepidids from African shrews, Staphylocystis loossi and S. khalili. The new species differs from both of them by a much smaller strobila size and fewer proglottids. The rostellar hooks in the new species are more numerous and smaller in size than in S. loossi. The rostellar hooks in R. gnoskei n. sp. are almost three times shorter than hooks in S. khalili. The hook shape in both S. loossi and S. khalili is substantially different from that in the new species. Molecular phylogenetic analysis indicates that the new species is close to Rodentolepis fraterna, a parasite of rodents. The new species clearly differs from R. fraterna by the much shorter strobila, larger hooks, relatively longer cirrus sac, rate of proglottid development, the number of eggs per proglottid and parasitism in shrews. Although the new species fits the current diagnosis of Rodentolepis, its generic allocation is provisional and will likely be revised in the future because the type species of Rodentolepis, R. straminea, belongs to a different well supported clade. Thus, a new genus needs to be established for the lineage that includes R. fraterna and R. gnoskei n. sp. However, this systematic rearrangement is not recommended until Staphylocystis pistillum, the type species of Staphylocystis, is included in future phylogenetic analyses. Rodentolepis gnoskei n. sp. is the first tapeworm species reported from shrews in Malawi and the first species of cestode reported from S. varilla minor and any member of Suncus in Africa.

Molecular evolution of Azagny virus, a newfound hantavirus harbored by the West African pygmy shrew (Crocidura obscurior) in Côte d'Ivoire

BackgroundTanganya virus (TGNV), the only shrew-associated hantavirus reported to date from sub-Saharan Africa, is harbored by the Therese's shrew (Crocidura theresae), and is phylogenetically distinct from Thottapalayam virus (TPMV) in the Asian house shrew (Suncus murinus) and Imjin virus (MJNV) in the Ussuri white-toothed shrew (Crocidura lasiura). The existence of myriad soricid-borne hantaviruses in Eurasia and North America would predict the presence of additional hantaviruses in sub-Saharan Africa, where multiple shrew lineages have evolved and diversified.MethodsLung tissues, collected in RNAlater®, from 39 Buettikofer's shrews (Crocidura buettikoferi), 5 Jouvenet's shrews (Crocidura jouvenetae), 9 West African pygmy shrews (Crocidura obscurior) and 21 African giant shrews (Crocidura olivieri) captured in Côte d'Ivoire during 2009, were systematically examined for hantavirus RNA by RT-PCR.ResultsA genetically distinct hantavirus, designated Azagny virus (AZGV), was detected in the West African pygmy shrew. Phylogenetic analysis of the S, M and L segments, using maximum-likelihood and Bayesian methods, under the GTR+I+Γ model of evolution, showed that AZGV shared a common ancestry with TGNV and was more closely related to hantaviruses harbored by soricine shrews than to TPMV and MJNV. That is, AZGV in the West African pygmy shrew, like TGNV in the Therese's shrew, did not form a monophyletic group with TPMV and MJNV, which were deeply divergent and basal to other rodent- and soricomorph-borne hantaviruses. Ancestral distributions of each hantavirus lineage, reconstructed using Mesquite 2.74, suggested that the common ancestor of all hantaviruses was most likely of Eurasian, not African, origin.ConclusionsGenome-wide analysis of many more hantaviruses from sub-Saharan Africa are required to better understand how the biogeographic origin and radiation of African shrews might have contributed to, or have resulted from, the evolution of hantaviruses.

Linking lineage diversification to climate and habitat heterogeneity: phylogeography of the southern African shrew Myosorex varius

Aim The phylogeographical patterning of taxa distributed in the Cape Floristic Region (CFR) of southern Africa has received much recent attention. Few studies, however, have focused on taxa with broad ecological requirements, such as the South African endemic shrew Myosorex varius (Soricidae). The species is considered a generalist and is distributed throughout the CFR and the grasslands of South Africa. Our aims were: (1) to investigate the fine-scale phylogeographical structure of M. varius through comprehensive spatial sampling across the entire distribution; and (2) to determine if the distribution of genetic structuring was correlated with environmental factors such as seasonal rainfall regimes. Location South Africa. Methods The phylogeographical structure of M. varius was determined by making use of 1029 sequenced characters derived from two independent markers (the mitochondrial hypervariable control region and an intron of a nuclear gene, signal transducer and activator of transcription 5A – STAT). Bayesian analysis of population structure (baps) and spatial genetic landscapes were used to describe broad-scale patterns of genetic diversity across the entire distribution of M. varius. Results Several geographically correlated lineages were detected within the species. The northern lineage comprised all individuals collected from the grassland and savanna habitats of South Africa and, although genetically diverse, did not show any significant geographically correlated substructure. The southern lineage, represented by individuals collected from the Western and Eastern Cape provinces of South Africa, displayed considerably more phylogeographical partitioning, with populations of M. varius in this region subdivided into western and eastern CFR groupings. Main conclusions Contrary to expectations, this study recovered high levels of spatial genetic structuring within the southern African generalist shrew species M. varius. This phylogeographical structure is consistent with that proposed by previous studies on other unrelated taxa, and this study contributes significantly to the growing body of work highlighting the importance of rainfall and associated vegetation types as factors influencing biodiversity patterns in the region.

Circadian rhythms of locomotor activity in the reddish‐grey musk shrew (Eulipotyphla: Soricidae) from South Africa

The circadian rhythm of locomotor activity in a southern African shrew, the reddish-grey musk shrew Crocidura cyanea was investigated. Thirteen individuals were subjected to three successive light cycles, each cycle lasting approximately 2 weeks: an LD cycle (12 h light/12 h dark), a DD cycle (constant darkness) and a DL cycle (an inverse of the LD cycle). All of the animals exhibited entrainment of their activity to the LD and DL lighting regimes. Locomotor activity of C. cyanea occurred predominantly during the dark phases of the LD cycle and the DL cycle. Under LD, the mean active phase (α) of C. cyanea was 10.8±0.3 h and the total percentage of activity was 78.9% during the dark phase. When subjected to constant darkness, the mean active phase increased to 13.2±01.8 h and all animals expressed free-running rhythms of locomotor activity (mean±1 sd=23.0±0.55 h; range=22.4–23.7 h). On the reverse LD cycle, the mean active phase was lowest (09.3±0.16 h) and the total percentage of activity was 71.5% during the dark phase of the cycle. The reddish-grey musk shrew possesses a strong circadian rhythm of locomotor activity that predominantly occurs during the dark phase and consequently the musk shrew may essentially be considered a nocturnal mammal.

Molecular phylogenetics reveals Messinian, Pliocene, and Pleistocene colonizations of islands by North African shrews

Molecular phylogenetics reveals Messinian, Pliocene, and Pleistocene colonizations of islands by North African shrews

Impact of removal pitfall trapping on the community of shrews (Mammalia : Soricidae) in two African tropical forest sites.

Removal trapping is still used for the study of tropical African shrews biodiversity and ecology, because shrew species identification requires cranio-dental analyses due to the existence of sibling species. Pitfall trapping has been found to be the most effective protocol to collect shrews. However, the impact of removal pitfall-trapping on density and diversity of shrew species is still unknown. In this paper, we test this impact on two African tropical forest shrew communities, by comparing the results of two trapping sessions conducted in two consecutive years. Our results support the view that removal trapping, with conditions described in this paper, does not adversely affect local population numbers and shrew species richness.

New findings of a specialized spine cuticle in porcupines (Rodentia: Hystricomorpha) and tenrecs (Insectivora: Tenrecidae).

Earlier, we demonstrated the presence of inverted cuticle on the protective spines of New World porcupines. In this cuticle, the scales do not point upwards (to the top of the stem) as they usually do; they have an opposite orientation towards the base of the spine and form a distinctive harpoonlike structure [1‐3]. In Old World porcupines, the cuticle of protective spines either is inverted or forms a brush that has a stopper function and consists of large scales that are normally oriented but modified and stuck out ( Atherurus ). Examples of characteristic cuticles are the stratified mosaic cuticle in the grooves of A. macrourus spines and the folded, ribbed, and concave spine cuticle in Proechimys, Lonchotrix , tropical Neacomys, Tokudaia, Maxomys, Arvicanthis, Leopoldamys, Acomys , and Niviventer [2, 3]. Continuing the studies in this field, I found new facts of the presence of a specialized cuticle in mammalian spines. Using a JSM 840 A scanning electron microscope, I studied the fine structure of spines and hair taken from napes (sometimes, from bellies and tails) of several species. The material was kindly provided by the National Museum of Natural History (Smithsonian Institution, Washington, DC, United States). New World porcupines (Erethizontidae) include the prehensile-tailed porcupine Coendou prehensilis (male, specimen no. USNM 281902) and porcupines from Amazon ( Echinoprocta rufescens , USNM 236908), Columbia, and Mexico ( Sphiggurus mexicanus , USNM 324111). I studied the long-tailed porcupine Trichys fasciculatus macrotis (a male obtained from western Malaysia, USNM 489379) as a representative of Old World porcupines (Hystricidae). The tenrec species studied (Insectivora: Tenrecidae) included the small Madagascar hedgehog Echinops telfairi (female, USNM 328615), the burrowing tenrec Geogale aurita (juv., USNM 395676), the striped tenrec Hemicentetes semispinosus (USNM 294508), the aquatic tenrec Limnogale mergulus (USNM 398583), the long-tailed tenrec Microgale cowani (female, USNM 328671), the rice tenrec Oryzorictes hova (female, USNM 578789), the hedgehog tenrec Setifer setosus (male, USNM 341635), the giant African water shrew Potamogale velox (a female obtained from Zaire, USNM 5378789), and the tailless tenrec Tenrec ecaudatus (a female obtained from Mauritius Island, USNM 341849).

Phylogeny and Evolution of African Shrews (Mammalia: Soricidae) Inferred from 16s rRNA Sequences

Current phylogenetic hypotheses on the African Crocidurinae (Soricidae) are based upon morpho-anatomical, karyological, and allozyme studies. The present study attempts to resolve the interrelationships among African Crocidurinae and their relationships to Eurasian Crocidurinae and to the subfamily Soricinae, on the basis of partial mitochondrial 16s rRNA sequences (549 bp). This is the first molecular study to include all but one of the nine currently recognized African shrew genera. In agreement with current views, two major lineages emerge. The first lineage includes Myosorex and Congosorex and supports the existence of a myosoricine taxon. The second lineage includes the six remaining genera. The genus Sylvisorex appears to be polyphyletic, whereas species of the controversial genus Crocidura are monophyletic. The genus Suncus presumably originated in Africa. The monospecific genera Ruwenzorisorex and Scutisorex and the two representatives of Paracrocidura cluster with species of other genera. Grouping patterns of species from different continents suggest that there have been multiple exchanges between Africa and Eurasia. The time estimates of these exchanges, inferred from two independent fossil-based calibrations of a molecular clock, coincide with the time estimates for migration events in other mammalian taxa.