Naked-nosed Kleintenrek

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Naked-nosed Kleintenrek
Systematics
without rank: Afroinsectiphilia
Order : Tenrecus (Afrosoricida)
Family : Tenreks (Tenrecidae)
Subfamily : Travel treks (Oryzorictinae)
Genre : Kleintenreks ( Microgale )
Type : Naked-nosed Kleintenrek
Scientific name
Microgale gymnorhyncha
Jenkins , Goodman & Raxworthy , 1996

The bare-nosed small tenrek ( Microgale gymnorhyncha ), sometimes also known as the bare-nosed small tanrek , is a species of mammal from the genus of the small tenreks within the tenrek family . It lives in a large area of ​​eastern Madagascar , where it prefers forests in the middle and higher mountains. Compared to other small tenreks, it is a medium-sized representative, like its relatives, the naked-nosed small tenrek is characterized by a spindle-shaped body, short, powerful legs and a long, pointed head. Also noteworthy are the bare nasal mirror , the short tail and the wide forefeet. Due to these characteristics, the animals may have adapted to a more subterranean way of life, but very little information is available about their exact behavior. The species was first described in 1996, the population is currently not considered endangered.

features

Habitus

The naked-nosed Kleintenrek is a medium-sized representative of the Kleintenreks. Investigations of four individuals from the Andringitra Mountains showed a total length of 15.3 to 15.5 cm. Of this, 9.4 to 9.5 cm is the head-trunk length and 5.9 to 6.1 cm is the tail. Two individuals from the Anjanaharibe massif had head-body lengths of 10.0 and 10.1 cm and tail lengths of 6.3 and 7.1 cm, respectively. In three individuals from the Marojejy massif , the corresponding values ​​were 8.4 to 9.6 cm and 7.5 cm each. The body weight was 15.5 to 19.0 g, 17.5 to 20.0 g and 19.5 to 26.0 g. Like all Kleintenreks, the animals are generally characterized by a spindle-shaped body with short, powerful limbs and a long, narrow head tapering to the front. The tail is significantly shorter than the rest of the body. The fur has a soft, shiny texture. Gray-brown tones dominate the back and gray tones on the belly. The back hair is designed in three colors with light gray bases, light yellowish gray shafts and strong brown tips. In the case of the hair on the underside, the shafts do not stand out due to a separate coloring. Guide hairs usually have a dark brown to black tint. The snout is elongated and has a trunk-like elongated nose that clearly protrudes over the mouth area. The nasal mirror is noticeably large, it is ribbed and bare on the sides. It extends back about 6 to 7 mm. The eyes and ears are small, the latter are only 11 to 18 mm long and are partially hidden in the fur. When folded forward, the front end is clearly behind the eyes. The tail is colored a little darker on top than on the underside. The hands and feet, on the other hand, have a light color. They each have five rays. The forefoot in particular is very wide and has strong, elongated claws. The rear foot length is 14 to 15 mm. Females have one pair of variable teats in the chest and / or abdominal region and two pairs in the lumbar region.

Skull and dentition features

The skull is elongated, relatively delicate and pear-shaped in outline. Its greatest length varies from 24.6 to 28.7 mm, the greatest width at the skull is 10.1 to 11.3 mm. The rostrum is long and narrow, but does not end pointedly at the front, but rather blunt, while the entire posterior area of ​​the skull appears short. The nasal bone extends backwards into the eye region, in front it contacts the median jawbone at the level of the canine and the anterior premolar . In contrast, the frontal and parietal bones are comparatively short, the occiput is high. The lower jaw is slightly curved and elongated, the mental foramen lies below the penultimate premolar. The bite is slightly reduced, as with all microgale and comprises a total of 40 teeth with the following dental formula : . The front teeth are not in a closed row, but are separated from each other by longer diastemas . These are located in the upper dentition between the first incisor and the second premolar, in the lower dentition the gaps between the teeth start from the second incisor. The size of the upper incisors decreases from front to back, the canine in turn reaches the size of the anterior incisor. The latter is inclined slightly forward ( proodont ) above and below . All front teeth have additional cusps on the tooth crown. The anterior premolar (P2) of the upper and lower row of teeth is tricuspid , with three cusps on the chewing surface. It also protrudes beyond the canine. The molars are characteristically zalambdodont with three main cusps on the chewing surface. They are basically similar to the molars of the other Kleintenreks. The rearmost upper molar is reduced in size. The length of the upper row of teeth is 13.5 to 15.0 mm.

distribution

Distribution area of ​​the bare-nosed small tenrec

The bare-nosed Kleintenrek is endemic to Madagascar . The animals inhabit the hard-leaf and tropical rainforests of the middle and higher mountain ranges in the eastern part of the island. Their occurrence extends in a more or less wide strip from the north to the south of the island. The height distribution ranges from 970 to 1990 m, in the mountain regions the naked-nosed Kleintenrek prefers to inhabit valley floors, less often mountain slopes. It has not been proven in lower-lying landscapes. Significant localities are on the Tsaratanana massif in the province of Mahajanga , on the Anjanaharibe massif and on the Marojejy massif in the province of Antsiranana , in the forest area of ​​Ambatovy-Analamay-Torotorofotsy in the province of Toamasina , in the forest corridor of Anjozorobe-Angavo in the border area of ​​the provinces Toamasina and Antananarivo , in the forest areas of Ankazomivady and Ranomafana and in the Andringitra Mountains in the province of Fianarantsoa and in the Anosyenne Mountains in the province of Toliara . Somewhat separated from the main occurrence, the species is also recorded in the forest area of ​​Ambohitantely north and in the forest area of ​​Tsinjoarivo south of Antananarivo in the province of the same name. In many parts of the distribution area of the nude nasal Kleintenrek comes sympatrically before with other members of the genus, such as the Cowan-Kleintenrek ( Microgale cowani ), the little long-tailed Kleintenrek ( Microgale longicaudata ), the shrew Kleintenrek ( Microgale soricoides ) or Zwergkleintenrek ( Microgale parvula ). The species is relatively difficult to observe, so data on the frequency and size of the population are not available.

Way of life

The way of life of the naked-nosed Kleintenrek is almost unexplored. Morphologically it is very similar to the Grazilen Kleintenrek ( Microgale gracilis ). Like this, the species may live partly underground. Among other things, the widened forefeet with the elongated claws, the small eyes and the ears hidden under the fur as well as the long muzzle with the large nose mirror speak for this . An individual in the Anjanaharibe massif was caught right at the entrance to a cavity between tree roots. The dentition with the numerous gaps between the teeth allows a specialized insectivorous diet to be adopted, which has also been confirmed by isotope studies on animals from the forest area of ​​Tsinjoarivo. Individual intestinal remains that were examined revealed the consumption of indeterminable arthropods . A pregnant female captured in November 1994 carried three embryos , two in the right and one in the left fallopian tube , each 5 mm in length. So far, lactating females have been observed in December. Fleas of the genus Paractenopsyllus and ticks of the genus Ixodes have been identified as external parasites , and the single-cell Eimeria has also been identified as an internal parasite.

Systematics

Internal systematics of the Kleintenreks according to Everson et al. 2016
 Microgale  



 Microgale pusilla


   

 Microgale majori


   

 Microgale principula


   

 Microgale jenkinsae


   

 Microgale longicaudata






   

 Microgale mergulus


   

 Microgale parvula




   



 Microgale brevicaudata


   

 Microgale grandidieri



   

 Microgale drouhardi


   

 Microgale monticola


   

 Microgale taiva





   



 Microgale gracilis


   

 Microgale thomasi


   

 Microgale cowani


   

 Microgale jobihely





   

 Microgale dryas


   

 Microgale gymnorhyncha




   

 Microgale soricoides


   

 Microgale fotsifotsy


   

 Microgale nasoloi







Template: Klade / Maintenance / Style

The nude nasal Kleintenrek is a kind from the genus of microgale ( Microgale ) within the family of tenrecs (Tenrecidae). Together with the rice burrowers ( Oryzorictes ) and the representatives of the genus Nesogale, the Kleintenreks form the subfamily of the Reistenreks (Oryzorictinae). With more than 20 species, they are also the most diverse member of the Tenreks. According to some morphological features, they are also considered to be more originally within the family. According to molecular genetic analyzes, the genus originated in the Lower Miocene around 16.8 million years ago, after which it diversified very strongly. Today's representatives are adapted to different ways of life, so there are forms that sometimes dig underground, live above ground, or tree-climbing and water-dwelling forms. The majority of the Kleintenreks inhabit the humid forests of eastern Madagascar, a few species are also found in the drier landscapes of the western part of the island. Within the genus, different kinship groups can be identified both morphologically and genetically. Outwardly, the naked-nosed Kleintenrek is very similar to the Grazilen Kleintenrek ( Microgale gracilis ), but from a genetic point of view, the Dryad Kleintenrek ( Microgale dryas ) is its closest relative.

No distinction is made between subspecies of the bare-nosed mineroll, but due to its wide distribution, certain characteristic variations between the individual populations are noticeable. Animals from the Anjanaharibe massif in the north of the distribution area seem to be on average larger than those from the Andringitra mountains in the south.

The first scientific description of the species comes from Paulina D. Jenkins , Steven M. Goodman and Christopher J. Raxworthy from 1996. They examined more than half a dozen individuals from the Andringitra Mountains in southwest Madagascar and from Fanovana in the central highlands . The holotype , a full-grown female, was collected by Goodman in mid-December 1993 during a research expedition near the Volotsangana River around 38 km south of Ambalavao in the Andringitra Mountains at an altitude of 1,625 m above sea level. The area is considered a type region of the bare-nosed lesser tenreks. The species name gymnorhyncha is derived from the Greek words γυμνός ( gymnos ) for "naked" and ρύγχος ( rhynchos ) for "trunk" or "snout". So it refers to the strikingly large and bare nose mirror.

Threat and protection

There are only a few threats to the population of the bare-nosed miner. Especially in the middle mountain areas, local grazing, logging combined with forest destruction and fires can affect the individual populations . Due to the wide distribution and the assumed large total population, the IUCN lists the species as "not threatened" ( least concern ). It is represented in numerous nature reserves, such as the Andringitra National Park , the Ranomafana National Park , the Andohahela National Park and the Marojejy National Park . In order to preserve the bare-nosed miner, intensive studies of its general biology and ecology as well as its frequency are required.

literature

  • Paulina D. Jenkins, Steven M. Goodman and Christopher J. Raxworthy: The Shrew Tenrecs (Microgale) (Insectivora: Tenrecidae) of the Réserve Naturelle Intégrale d'Andringitra, Madagascar. Fieldiana Zoology 85, 1996, pp. 191-217 ( [2] )
  • Paulina D. Jenkins: Tenrecidae (Tenrecs and Shrew tenrecs). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 134–172 (pp. 169–170) ISBN 978-84-16728-08-4

Individual evidence

  1. ↑ a b c d e f Paulina D. Jenkins, Steven M. Goodman and Christopher J. Raxworthy: The Shrew Tenrecs (Microgale) (Insectivora: Tenrecidae) of the Réserve Naturelle Intégrale d'Andringitra, Madagascar. Fieldiana Zoology 85, 1996, pp. 191-217
  2. ↑ a b c d e f Steven M. Goodman and Paulina D. Jenkins: The Insectivores of the Réserve Spéciale d'Anjanaharibe-Sud, Madagascar. Fieldiana Zoology 90, 1998, pp. 139-161
  3. ↑ a b c d Steven M. Goodman and Paulina D. Jenkins: Tenrecs (Lipotyphla; Tenrecidae) of the Parc National de Marojejy, Madagascar. Fieldiana Zoology 97, 2000, pp. 201-229
  4. ^ A b Steven M. Goodman, Paulina D. Jenkins and Mark Pidgeon: Lipotyphla (Tenrecidae and Soricidae) of the Réserve Naturelle Intégrale d'Andohahela, Madagascar. Fieldiana Zoology 94, 1999, pp. 187-216
  5. ↑ a b c Paulina D. Jenkins: Tenrecidae (Tenrecs and Shrew tenrecs). In: Don E. Wilson and Russell A. Mittermeier (eds.): Handbook of the Mammals of the World. Volume 8: Insectivores, Sloths and Colugos. Lynx Edicions, Barcelona 2018, pp. 134–172 (pp. 167–168) ISBN 978-84-16728-08-4
  6. ↑ Claudette Patricia Maminirina, Steven M. Goodman and Christopher J. Raxworthy: Les micro-mammifères (Mammalia, Rodentia, Afrosoricida et Soricomorpha) du du massif Tsaratanana et biogeography of Forests de montagnes de Madagascar. Zoosystema 30, 2008, pp. 695-721
  7. ↑ Voahangy Soarimalala and Steven M. Goodman: Diversité biologique the micromammifères non volants (Lipotyphla et Rodentia) dans le complexe Marojejy Anjanaharibe-sud. In: Steven M. Goodman and Lucienne Wilmé (eds.): Nouveaux résultats faisant référence à l'altitude dans la région des massifs montagneux de Marojejy et d'Anjanaharibe-sud. Recherche pour le développement, Série Sciences biologiques, Center d'Information et de Documentation Scientifique et Technique 19, 2003, pp. 231-276
  8. ↑ Voahangy Soarimalala and Martin Raheriarisena: The non-volant and non-primate mammals of the Ambatovy Analamay forest. In: Steven. M. Goodman and V. Mass (Eds.): Biodiversity, exploration, and conservation of the natural habitats associated with the Ambatovy project. Malagasy Nature 3, 2010, pp. 153-177
  9. ↑ Voahangy Soarimalala, Landryh T. Ramanana, José M. Ralison and Steven M. Goodman: Les petits mammifères non-volants du “Couloir forestier d'Anjozorobe - Angavo”. In: Steven M. Goodman, Achille P. Raselimanana and Lucienne Wilmé (eds.): Inventaires de la faune et de la flore du couloir forestier d'Anjozorobe - Angavo. Recherche pour le développement, Série Sciences biologiques, Center d'Information et de Documentation Scientifique et Technique 24, 2007, pp. 141-182
  10. ↑ Steven M. Goodman, Jean-Marc Duplantier, Pierre Jules Rakotomalaza, Achille Philippe Raselimalala, Rodin Rasoloarinson, Mamy Ravokatra, Voahangy Soarimalala and Lucienne Wilmé: Inventaire biologique de la Forêt d'Ankazomivady, Ambositra. Akon'ny Ala 24, 1998, pp. 19-32
  11. ↑ Voahangy Soarimalala, Steven M. Goodman, H. Ramiaranjanahary, LL Fenohery and W. Rakotonirina: Les micromammifères non-volants du Parc National de Ranomafana et du couloir forestier qui le relie au Parc National d'Andringitra. Dans Inventaire biologique du Parc National de Ranomafana et du couloir forestier qui la relie au Parc National d'Andringitra. In: Steven M. Goodman and VR Razafindratsita (eds.): Recherches pour le Développement. Série Sciences Biologiques 17, 2001, pp. 199-229
  12. ↑ Landryh Tojomanana Ramanana: Petits mammifères (Afrosoricida et Rodentia) nouvellement recensés dans le Parc National d'Andohahela (parcelle 1), Madagascar. Malagasy Nature 4, 2010, pp. 66-72
  13. ↑ Steven M. Goodman and Daniel Rakotondravony: The effect of forest fragmentation and isolation on insectivorous small mammals (Lipotyphla) on the Central High Plateau of Madagascar. Journal of Zoology 250, 2000, pp. 193-200
  14. ↑ Steven M. Goodman, Daniel Rakotondravony, Marie Jeanne Raherilalao, Domoina Rakotomalala, Achille P. Raselimanana, Voahangy Soarimalala, Jean-Marc Duplantier, Jean-Bernard Duchemin and J. Rafanomezantsoa: Inventaire biologique de la Foret de Tsinjoarivo, Ambatolampy. Akon'ny Ala 27, 2000, pp. 18-27
  15. ↑ a b P. J. Stephenson, Voahangy Soarimalala and Steven M. Goodman: Microgale gymnorhyncha. The IUCN Red List of Threatened Species 2016. e.T62014A97191808 ( [1] ); last accessed on July 30, 2016
  16. ↑ Melanie Dammhahn, Voahangy Soarimalala and Steven M. Goodman: Trophic Niche Differentiation and Microhabitat Utilization in a Species-rich Montane Forest Small Mammal Community of Eastern Madagascar. Biotropica 45 (1), 2013, pp. 111-118
  17. ↑ J.-B. Duchemin: Leptopsyllines from Madagascar (Insecta: Siphonaptera: Ceratophyllidae): Description of five new species of Paractenopsyllus Wagner, (1938). Parasite 11, 2004, pp. 59-70
  18. ↑ Michael W. Hastriter and Carl W. Dick: A description of Paractenopsyllus madagascarensis sp. n. and the female of Paractenopsyllus raxworthyi Duchemin & Ratovonjato, 2004 (Siphonaptera, Leptopsyllidae) from Madagascar with a key to the species of Paractenopsyllus. ZooKeys 13, 2009, pp. 43-55
  19. ↑ Steven M. Goodman, H. Rico Randrenjarison Andriniaina, Voahangy Soarimalala and Jean-Claude Beaucournu: The Fleas of Endemic and Introduced Small Mammals in Central Highland Forests of Madagascar: Faunistics, Species Diversity, and Absence of Host Specificity. Journal of Medical Entomology 52 (5), 2015, pp. 1135-1143
  20. ↑ Malala N. Rakotomanga, Steven M. Goodman, Voahangy Soarimalala, Sebastien Boyer and Dmitry Apanaskevich: Les tiques dures (Acari: Ixodidae) ectoparasites de micromammifères non-volants dans la forêt d'Ambohitantely, Madagascar. Malagasy Nature 12, 2017, pp. 59-67
  21. ↑ Lee Couch, Juha Laakkonen, Steven Goodman, and Donald W. Duszynski: Two New Eimerians (Apicomplexa) from Insectivorous Mammals in Madagascar. Journal of Parasitology 97 (2), 2011, pp. 293-296
  22. ↑ a b c Kathryn M. Everson, Voahangy Soarimalala, Steven M. Goodman and Link E. Olson: Multiple loci and complete taxonomic sampling resolve the phylogeny and biogeographic history of tenrecs (Mammalia: Tenrecidae) and reveal higher speciation rates in Madagascar's humid forests . Systematic Biology 65 (5), 2016, pp. 890-909 doi: 10.1093 / sysbio / syw034
  23. ^ JF Eisenberg and Edwin Gould: The Tenrecs: A Study in Mammalian Behavior and Evolution. Smithsonian Institution Press, 1970, pp. 1-138
  24. ^ RDE MacPhee: The Shrew Tenrecs of Madagascar: Systematic Revision and Holocene Distribution of Microgale (Tenrecidae, Insectivora). American Museum Novitates 2889, 1987, pp. 1-45

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