Drouhard-Kleintenrek

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Drouhard-Kleintenrek
Systematics
without rank: Afroinsectiphilia
Order : Tenrecus (Afrosoricida)
Family : Tenreks (Tenrecidae)
Subfamily : Travel treks (Oryzorictinae)
Genre : Kleintenreks ( Microgale )
Type : Drouhard-Kleintenrek
Scientific name
Microgale drouhardi
G. Grandidier , 1934

The Drouhard-Kleintenrek or Drouhard-Kleintanrek ( Microgale drouhardi ) is a species of mammal from the genus Kleintenreks within the Tenreks family . It belongs to the medium-sized representatives of the genus and, like the other members of the family, is characterized by a spindle-shaped body, strong limbs and a long, narrow head tapering to a point. The coat is generally dark in color, highlighting a dark stripe along the center line of the back. The animals inhabit larger parts of eastern Madagascar , they occur both in lowlands and in higher mountain regions. Tropical rainforests and marshlands are preferred habitats . The way of life of the Drouhard Kleintenreks has hardly been researched. The species received its first scientific description in 1934 , in some cases it was equated with the Cowan-Kleintenrek . The population is safe.

features

Habitus

The Drouhard-Kleintenrek is a medium-sized representative of the Kleintenreks. According to a study of more than 40 individuals from the entire range, the head-torso length is 6.3 to 8.3 cm and the tail length 5.3 to 8.3 cm. The tail is therefore about the same length as the rest of the body or remains a little shorter. The body weight of three not fully grown individuals from the Andringitra Mountains in southeastern Madagascar is given as 8.2 to 9.2 g, a fully grown male from Analamazaotra in the eastern part of the island weighed 11 g. Similar to the other Kleintenreks, the body is characterized by its spindle-shaped shape, the limbs are short and strong, the head has a long, narrow shape and ends with a pointed snout. The distinctive ears are 13 to 15 mm long. The back fur shows a dark brown to brown or reddish brown color. A 4 mm wide, darker stripe runs along the center line from the top of the head to the base of the tail. The individual hairs of the dorsal fur have light gray bases, a reddish upper shaft section and brown tips. The hair from the dark stripe and the guide hairs lack the reddish color section. Shiny silver, yellowish-brown to reddish-brown colors dominate the underside. Here the individual hairs are characterized by gray bases and yellowish brown to reddish brown tips. The transition from the back to the peritoneum drawing stands out clearly on the sides. The tail is two-colored, dark brown on top, yellowish or reddish brown underneath. It has a shed coat, which in turn is covered by a short-haired fur, the individual hairs in the rear third of the tail have an average length of two rows of scales. The hands and feet each have five rays. The rear of the foot is colored dark brown on the upper and outside, on the inside there are also reddish to yellowish-brown colorations. The length of the rear foot varies between 13 and 19 mm.

Skull and dentition features

The skull reaches a length of 21 to 24 mm, the greatest width measured on the brain skull is 8.5 to 9.7 mm. Overall, the skull is moderately large, the rostrum is only slightly elongated, flat, but relatively wide. The nasal bone is extended backwards into the eye region, the parietal bone is slightly inflated upwards. The connection between the parietal bone and the occiput is either round or slightly bent. The rear skull is moderately broad, flat and short in shape. The zygomatic arch is only incompletely developed. The dentition consists of 40 teeth and has the following dental formula of: . Usually there are diastemas in the upper row of teeth from the first incisor to the second premolar (P3), so that the front row of teeth is not closed. In the lower dentition, there are only gaps in front of and behind the first premolar (P2). The front teeth have additional cusps on the tooth crown, with the exception of the last upper incisor, which is more like a canine tooth ( caniniform ). The upper canine is long and slender and is usually the tallest tooth in the upper dentition. The molars show no differences from those of other Kleintenreks. Your chewing surface pattern is designed zalambdodont and is characterized by three main cusps. The last upper molar is reduced in size. The length of the upper row of teeth is 9.7 to 10.7 mm.

distribution

Distribution area of ​​the Drouhard-Kleintenreks

The Drouhard-Kleintenrek is endemic in Madagascar and occurs there in a relatively large distribution area. This extends in a more or less wide strip from north to south over the eastern part of the island state. Significant localities are found in the Montagne d'Ambre as well as in the Manongarivo reserve and on the Masoala peninsula , all in the Antsiranana province ; the latter was only detected in 2018. In addition, the species was found in the Tsaratanana massif in the Mahajanga province , in the forest areas of Ambatovy-Analamay-Torotorofotsy, Analamazaotra and Zahamena in the Toamasina province and in the Andringitra mountains in the Fianarantsoa province occupied. The altitude distribution extends from 350 to 2350 m above sea level, which is one of the largest ranges within the Kleintenreks. The highest point of discovery is on the Tsaratanana massif, where the Maromokotro, the highest mountain on the island, rises. The animals inhabit moist rainforests and marshland near the edges of the forest, but avoid heavily overgrown forests. Due to the wide distribution in height, the Drouhard-Kleintenrek appears sympatric with numerous other representatives of the Kleintenreks , the Cowan ( Microgale cowani ) and the Taiva-Kleintenrek ( Microgale taiva ) are particularly noteworthy . However, there are too few studies available to differentiate the individual representatives ecologically. The species is generally considered to be relatively common.

Way of life

The way of life of the Drouhard Kleintenreks is largely unexplored. It is ground dwelling and agile, it often retreats in dense leaf shedding. Animals kept briefly in human captivity preferred to exterminate grasshoppers , as well as earthworms and frogs . The average body temperature is 33.9 ° C, it is assumed that it is in accordance with the Cowan Kleintenrek ( Microgale cowani ) and in contrast to other tenreks, with varying outside temperatures, significantly more stable. At rest, the metabolic rate is around 132% above the value that would be expected in mammals of the same size. The frett cat occasionally appears as a predator , as studies of droppings from the Montagne d'Ambre show. The known external parasites include fleas of the genus Paractenopsyllus , while the single cell Eimeria has been identified as the internal one .

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 Drouhard-Kleintenrek is a kind from the genus of microgale ( Microgale ) within the family of tenrecs (Tenrecidae). The Kleintenreks also form part of the subfamily of the Reistenreks (Oryzorictinae), to which the rice burrowers ( Oryzorictes ) and the representatives of the genus Nesogale are also referred. In addition, with more than 20 species, the Kleintenreks also represent the most diverse member of the Tenreks. Due to some morphological features, they are considered to be originally within the family. According to molecular genetic analyzes, the genus originated in the Lower Miocene around 16.8 million years ago and diversified very much in the period that followed. 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 live in the damp forests of eastern Madagascar, but 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 detected both morphologically and genetically. Externally, the Drouhard-Kleintenrek is very similar to the Cowan-Kleintenrek ( Microgale cowani ) and the Taiva-Kleintenrek ( Microgale taiva ). The genetic data suggest that the Drouhard-Kleintenrek is the sister taxon of a group made up of the mountain-Kleintenrek ( Microgale monticola ) and the Taiva-Kleintenrek.

No distinction is made between subspecies of the Drouhard lesser tenreks. However, the animals show strong regional variations in the color of their fur. Animals from the Montagne d'Ambre in the north are dark brown with more or less dark washings, those from the more central-eastern Madagascar show light brown or reddish-brown colors, while in the Andringitra Mountains in the south, individuals with a gray-brown color dominate. There are also differences in the form as well as the length and width of the back stripe. Also noteworthy are certain differences in size between the individual populations with larger animals in the north than in the central-eastern part of Madagascar, although no connection between size and geographical origin has yet been established. In addition, there are deviations in the dimensions of the animals depending on the altitude. According to the observations, animals from higher mountain areas are on average larger than those from lower altitudes.

The first scientific description of the Drouhard-Kleintenreks comes from Guillaume Grandidier in 1934. Grandidier had six individuals from the vicinity of Antsiranana in the far north of Madagascar . The animals had been discovered by E. Drouhard, a former forest inspector in northern Madagascar, and Grandidier named the species in his honor. He identified an individual as a holotype , which he identified as a fully grown female individual. In his essay, Grandidier highlighted the very dark color of the coat as a special characteristic of Drouhard-Kleintenrek, and he also observed dark stripes along the central back, which he assumed, however, only appeared in young animals and disappeared with adulthood. The information about the find area is rather vague with environs de Diego-Suarez ("Vicinity of Diego-Suarez", today Antsiranana), as the region has various types of landscape, ranging from dry, open habitats to moist forests. Most representatives of the Kleintenreks can be found in the more humid eastern part of Madagascar, so Ross DE MacPhee assumed in a general revision of the Kleintenreks in 1987 that the type series of the species possibly came from the Montagne d'Ambre. In addition, MacPhee recognized from the development of the dentition that the type specimen is a not fully grown animal.

In 1948, led Terence Morrison-Scott with Microgale melanorrhachis a one outwardly very similar way, this was done with the help of an adult believes Morrison-Scott female in the area of Perinet in the region of today's National Park Mantadia Andasibe in eastern Madagascar (the type specimen is but also a young animal according to MacPhee). Morrison-Scott saw the olive-brown fur color and a dark stripe on the back as characteristic of his new species. The specific epithet , which comes from the Greek and is composed of the words μελαν ( melan ) for "black" and ῥάχις ( rháchis ) for "back" , also refers to the latter . Morrison-Scott compared Microgale melanorrhachis with the Drouhard-Kleintenrek, which he found to be much darker in overall color. While both species were considered independent for the next 50 years, MacPhee combined both Microgale drouhardi and Microgale melanorrhachis with the Cowan Kleintenrek in his 1987 revision of the Kleintenreks. The basis for this was mainly the consistency of the tooth features as well as the tooth and dentition dimensions. MacPhee saw a further clue in the striations on the back, as some individuals of the Cowan Lesser Tenrec had occasionally been described with such a fur pattern. The equation of Microgale drouhardi and Microgale melanorrhachis with the Cowan-Kleintenrek, however, was viewed critically by subsequent authors and hardly agreed with MacPhee's opinion. In the mid-1990s , Christopher J. Raxworthy and fellow researchers were able to show, when investigating animals from the Montagne d'Ambre, that none of the animals that were identified as certain to Cowan-Kleintenrek had a striped back. On the other hand, the sympatric striped Kleintenreks, which they associated with Microgale melanorrhachis , were all smaller than the Cowan Kleintenrek. In addition, the members of both groups also showed a slightly different choice of habitat, which was evidence enough for the researchers to assume that each species was independent. Peter J. Stephenson came to a similar conclusion when analyzing animals from various sites in eastern Madagascar. He also noted that the back striation does not only occur in young animals, but is also a characteristic of the old animals. In 1997 , Paulina D. Jenkins and colleagues again analyzed the known individuals from around a dozen localities where Microgale melanorrhachis and Microgale drouhardi were detected. They recognized that both species are conspecific and synonymized Microgale melanorrhachis , citing the priority of the name with Microgale drouhardi . They also assigned the striped representatives of the Cowan Kleintenrek to the Drouhard-Kleintenrek.

Threat and protection

The IUCN classifies the Drouhard-Kleintenreks as “not threatened” ( least concern ). The classification is based on the wide distribution of the species and the assumed large population . Especially in the low altitudes of the distribution area, habitat losses can occur locally as a result of forest destruction through the removal of construction wood and firewood or during the conversion into agriculturally usable areas. No major hazards are known in higher mountain areas. The animals are found in several nature reserves, for example in the Montagne d'Ambre National Park , in the Zahamena National Park , in the Mantadia Andasibe National Park or in the Andringitra National Park . To better preserve the species, more intensive studies of the biology and ecology of the animals are necessary.

literature

  • Guillaume Grandidier: Deux nouveaux mammifère insectivores de Madagascar Microgale drouhardi et M.parvula. Bulletin du Muséum national d'histoire naturelle (2nd series) 6, 1934, pp. 474–476 ( [2] )
  • Paulina D. Jenkins, Christopher J. Raxworthy and Ronald A. Nussbaum: A new species of Microgale (Insectivora, Tenrecidae), with comments on the status of four other taxa of shrew tenrecs. Bulletin of the Natural History Museum of London (Zoology) 63 (1), 1997, pp. 1-12
  • 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 (p. 168) ISBN 978-84-16728-08-4

Individual evidence

  1. ↑ a b c d e 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 P. J. Stephenson: Taxonomy of shrew-tenrecs (Microgale ssp.) From eastern and central Madagascar. Journal of Zoology 235, 1995, pp. 339-359
  3. ^ A b T. CS Morrison-Scott: The Insectivorous Genera Microgale and Nesogale (Madagascar). Proceedings of the Zoological Society of London 118, 1948, pp. 817-822
  4. ↑ a b Guillaume Grandidier: Deux nouveaux mammifère insectivores de Madagascar Microgale drouhardi et M. parvula. Bulletin du Muséum national d'histoire naturelle (2e Série) 6, 1934, pp. 474–476
  5. ↑ a b c d e f g Paulina D. Jenkins, Christopher J. Raxworthy and Ronald A. Nussbaum: A new species of Microgale (Insectivora, Tenrecidae), with comments on the status of four other taxa of shrew tenrecs. Bulletin of the Natural History Museum of London (Zoology) 63 (1), 1997, pp. 1-12
  6. ↑ 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 (p. 167) ISBN 978-84-16728-08-4
  7. ↑ a b Christopher J. Raxworthy and Ronald A. Nussbaum: A rainforest survey of amphibians, reptiles and small mammals at Amber Mountain, Madagascar. Biological Conservation 69, 1994, pp. 65-73
  8. ↑ Voahangy Soarimalala: Exploitation des bois à précieux Masoala, Madagascar: quel impact sur les tenrecs? Afrotherian Conservation 14, 2018, pp. 20–32
  9. ↑ 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
  10. ↑ 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
  11. ^ PJ Stephenson: The small mammal fauna of Réserve Spéciale d'Analamazaotra, Madagascar: the effects of human disturbance on endemic species diversity. Biodiversity and Conservation 2, 1993, pp. 603-615
  12. ↑ a b c P. J. Stephenson, Voahangy Soarimalala and Steven M. Goodman: Microgale drouhardi. The IUCN Red List of Threatened Species 2016. e.T62012A97190851 ( [1] ); last accessed on August 26, 2016
  13. ^ Peter J. Stephenson, Paul A. Racey, and Félix Rakotondraparany: Maintenance and reproduction of tenrecs (Tenrecidae) at Parc Tsimbazaza, Madagascar. International Zoo Yearbook 33, 1994, pp. 194-201
  14. ^ Peter J. Stephenson and Paul A. Racey: Reproductive energetics of the Tenrecidae (Mammalia: Insectivora). II. The shrew-tenrecs, Microgale spp. Physiological Zoology 66 (5), 1993, pp. 664-685
  15. ^ Paul A. Racey and Peter J. Stephenson: Reproductive and energetic differention of the Tenrecidae of Madagascar. In: W. R Lourenço (Ed.): Biogéographie de Madagascar. Paris, 1996, pp. 307-319
  16. ↑ Steven M. Goodman, Paulina D. Jenkins and Olivier Langrand: Exceptional records of Microgale species (Insectivora: Tenrecidae) in vertebral food remains. Bonn Zoological Contributions 47 (1/2), 1997, pp. 135-138
  17. ↑ 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
  18. ↑ J.-B. Duchemin: Leptopsyllines from Madagascar (Insecta: Siphonaptera: Ceratophyllidae): Description of five new species of Paractenopsyllus Wagner, (1938). Parasite 11, 2004, pp. 59-70
  19. ↑ 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
  20. ↑ 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
  21. ^ JF Eisenberg and Edwin Gould: The Tenrecs: A Study in Mammalian Behavior and Evolution. Smithsonian Institution Press, 1970, pp. 1-138
  22. ↑ a b c d R. DE 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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