Red-shouldered elephant dog

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Red-shouldered elephant dog
Red-shouldered elephant dog (Rhynchocyon petersi)

Red-shouldered elephant dog ( Rhynchocyon petersi )

Systematics
Superordinate : Afrotheria
without rank: Afroinsectiphilia
Order : Elephant jerk (Macroscelidea)
Family : Elephant jerk (Macroscelididae)
Genre : Proboscis Dog ( Rhynchocyon )
Type : Red-shouldered elephant dog
Scientific name
Rhynchocyon petersi
Bocage , 1880

The red-shouldered elephant dog ( Rhynchocyon petersi ), also known as the black- and- brown elephant dog , is a species of mammal from the family of elephants (Macroscelididae). It is distributed in a narrowly limited range on the coast of East Africa and some offshore islands and inhabits forest landscapes of the coastal regions and the mountainous region. Characteristic is the trunk-like elongated nose and the short front and long rear legs. Little is known about the way of life of the species. It lives on the ground as a nimble runner and feeds mainly on insects . The number of offspring varies between one and three. The scientific introduction of the red-shouldered elephant dog took place in 1880. The population is viewed as endangered.

features

Habitus

Red-shouldered elephant dog at the Smithsonian Zoo

The red-shouldered proboscis dog is a medium-sized representative of the proboscis dog. It reaches a total length of 49.3 to 52.5 cm, the head-trunk length is 25.2 to 29 cm, the tail length is 21.8 to 25.2 cm. Males may become slightly larger than females. In some of the museum specimens examined, a male had a body length of 32.4 cm and a tail length of 23 cm; the corresponding values ​​for two females were 27 to 27.5 cm and 21.3 to 24 cm, respectively. Like all elephants, the red-shouldered elephant dog has a large head with a long, trunk-like nose and thin limbs with short front and long hind legs. The fur is shiny, the back is black from the shoulder blades to the thighs, the flanks are tinted reddish brown to dull chestnut brown, depending on the regional distribution. The belly always appears orange to reddish-brown in color, as does the head, which, however, can also appear slightly gray on the forehead. The ears are also orange-reddish brown and stand upright, their length is about 31 mm. The outside of the legs are orange-brown in color. The front and rear feet each have four toes with strong claws, the length of the rear foot varies from 67 to 83 mm. The tail is almost hairless and colored light orange. Irregular whitish spots appear at the top.

Skull and dentition features

The skull has a length of 67 to 69 mm, at the zygomatic arches it becomes 35 to 37 mm wide. The palatine bone measures about 36 mm. The lower jaw has a length of 52 mm. The bit consists of 34 to 36 teeth, the dental formula is: . The upper incisor , if present, is rather rudimentary. In males, the upper canine tooth can be 2.2 to 6.5 mm in length. The total length of the upper row of teeth is 26.5 to 28.1 mm.

distribution and habitat

Distribution area of ​​the red-shouldered proboscis dog

The distribution area of ​​the red-shouldered proboscis puppy covers a narrow region in eastern Africa . It occurs in the coastal area of ​​southeastern Kenya and northeastern Tanzania , for example from the Rabai Mountains near Mombasa to Dar-es-Salam in the south. In addition, it can also be found on the offshore islands of Zanzibar and Mafia . As a result, the species mainly inhabits coastal forests and the forests of the Eastern Arc Mountains . It prefers evergreen or partly deciduous forests, moist mountain forests and bush landscapes on coral limestone, but can also cope with heavily overgrown agricultural areas. The forest canopy should mostly be closed and the soil should be covered with a thick layer of leaves. A very far western occurrence was reported from Kibaya in the northern Tanzanian region Manyara , since this is already the savannah zone , it probably represents an isolated population in forest fragments. In general, the red-shouldered elephant dog is considered to be rather rare. In the 143 km² Chome Forest Reserve in the Pare Mountains of the Eastern Arc Mountains of Tanzania, an individual density of 19 animals per square kilometer was determined (a total of around 2700 animals in the reserve), in the Pugu Forest , also in the Eastern Arc Mountains, it was about 79 on a comparably large area. The overall range is most likely more fragmented.

Way of life

Territorial behavior

Red-shouldered elephant dog

Little information is available about the way of life of the red-shouldered elephant dog. It is diurnal and, like all elephant dogs, lives purely on the ground, where it moves four-footed, running or jumping, and can become very fast ( cursorial ). This is particularly advantageous in the case of danger, in which an animal quickly retreats into the thicket. In addition, the senses are very highly developed. When sighted, the red-shouldered elephant dog usually appears as a single animal, but it is assumed that males and females form monogamous pairs, as is also known from other elephants. In captive animals, unbound females show greater mutual tolerance than unbound males. Nests made of plant material on the ground serve as resting places.

nutrition

The diet consists mainly of insects . In the Nkuka Forest in Tanzania, it was observed that animals mainly ate migrant ants of the genus Dorylus .

Reproduction

The gestation period is around 40 days. The females usually give birth to one to three young animals that are only slightly developed with bare skin and closed eyes. The young remain in their own nest for the first three to four weeks. It is unknown whether the sire is involved in rearing or nest building, direct interactions with the offspring during the nest phase and later on have not yet been established. The mother animal visits the young once a day to suckle. The interval between two births is about 80 days, but it can be shortened to 40 if the young from the previous litter do not survive the birth. Life expectancy in the wild is unknown; animals kept in human care lived to be four years and six months old.

Parasites

Ticks such as Haemaphysalis , Ixodes and Rhipicephalus often appear as external parasites . Furthermore, fleas of the genera Ctenocephalides and Chimaeropsylla are documented.

Systematics

Internal systematics of elephants according to Heritage et al. 2020
 Macroscelididae  
  Macroscelidinae  
  Macroscelidini  


 Galegeeska


   

 Petrodromus


   

 Petrosaltator




   

 Macroscelides



  Elephantulini  

 Elephantulus



  Rhynchocyoninae  

 Rhynchocyon



Template: Klade / Maintenance / Style

The red-shouldered proboscis dog is a species from the genus of the proboscis dog ( Rhynchocyon ), to which a total of five species belong. The elephants in turn represent part of the family of elephants (Macroscelididae) within the order of the same name (Macroscelidea). This family includes smaller mammals that are endemic in Africa . They include a total of six genera, which are divided into two subfamilies. The proboscis are the only members of the subfamily Rhynchocyoninae, which is thus monotypical . They represent the largest forms within the elephant and are adapted to predominantly forested habitats . The Macroscelidinae , the second subfamily, include the elephant shrews ( Elephantulus ), the proboscis ( Petrodromus ) and the genera Macroscelides , Galegeeska and Petrosaltator . Their representatives are significantly smaller and inhabit dry to sometimes desert-like regions. According to molecular genetic studies, the two subfamilies separated in the Lower Oligocene about 32.8 million years ago. Diversification of the genus Rhynchocyon began in the late Middle Miocene about 9.7 million years ago.

Internal systematics of the proboscis dogs according to Carlen et al. 2017
 Rhynchocyon  

 Rhynchocyon chrysopygus


   


 Rhynchocyon stuhlmanni


   

 Rhynchocyon cirnei



   

 Rhynchocyon udzungwensis


   

 Rhynchocyon petersi





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The red-shouldered proboscis dog is closely related to the spotted proboscis dog ( Rhynchocyon cirnei ). It is unclear whether there is a gap between the distribution areas of both species or whether there is a hybridization zone . Some authors assume the latter, as some representatives of the red-shouldered elephant dog have an indistinct markings on the back, as is typical of the spotted elephant dog. Under this condition, the red-shouldered elephant dog could be regarded as a daughter of the spotted elephant.

Two subspecies are assigned to the red-shouldered elephant dog:

  • R. p. adersi Dollman , 1912; Zanzibar and Mafia ; The color of the fur on the shoulders, flanks and sometimes the belly is reddish brown to dull chestnut brown, the head is lighter but more reddish brown than yellowish, the feet are dark brown and, above all, on the back with numerous black banded hairs, the tail is clearly orange brown with more contrasting white spots
  • R. p. petersi Bocage , 1880; mainland East Africa ; The fur on the shoulders, flanks and belly is orange-red-brown, skull rather yellowish, feet orange-brown without black-banded hair, tail light orange at the base and cream-colored at the tip with little contrast to the white spots.

The first scientific description of the red-shouldered elephant dog was in 1880 by José Vicente Barboza du Bocage . An individual with a head-to-trunk length of 26 cm and a tail length of 18.5 cm was available to him for setting up the species. This was given to the Natural History Museum in Lisbon and came from the East African mainland across from the island of Zanzibar, which is also considered a type area. With the species name petersi , Bocage honored the German naturalist Wilhelm Peters , who had previously introduced several species of elephants.

Threat and protection

The distribution area of ​​the red-shouldered proboscis dog is very limited. The main threats are the loss and declining quality of the habitat due to changes in the landscape caused by agriculture, which leads to a fragmentation of the habitats. In addition, logging has a very negative effect on fuel or building material. The IUCN classifies the species as being "endangered" ( vulnerable ). Parts of their habitat are protected by national parks and nature reserves in both Kenya and Tanzania.

At the beginning of the 21st century, successful breeds of the red-shouldered elephant dog arose in the zoos of Philadelphia and Cincinnati , both in the USA . The populations there are still relatively small. In Europe , the species is currently kept in seven zoos, in Antwerp , in the Grzimek House in Frankfurt am Main , in Leipzig , in Prague , in Wroclaw , in Val-de-Reuil and in Rotterdam .

literature

  • Stephen Heritage: Macroscelididae (Sengis). 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. 206-234 (p. 228) ISBN 978-84-16728-08-4
  • Ronald M. Nowak: Mammals of the World. Johns Hopkins University Press, Baltimore 1999, ISBN 0-8018-5789-9
  • Galen B. Rathbun: Rhynchocyon petersi Black-and rufous Giant Sengi (Black-and rufous Elephant-shrew). In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 286-287

Individual evidence

  1. ↑ Francesco Rovero, Galen B. Rathbun, A. Perkin, T. Jones, DO Ribble, C. Leonard, RR Mwakisoma and N. Doggart: A new species of giant sengi or elephant-shrew (genus Rhynchocyon ) highlights the exceptional biodiversity of the Udzungwa Mountains of Tanzania. Journal of Zoology 274 (2), 2008, pp. 126-133
  2. ^ A b N. Hollister: East African mammals in the United States National Museum. Bulletin of the United States National Museum 99, 1918, pp. 1–194 (p. 28) ( [1] )
  3. ↑ a b Arthur Loveridge: Notes on East African Mammalia (other than horned ungulates) collected or kept in captivity 1915-1919, part 2. Journal of the East African and Uganda Natural History Society 5 (17), 1922, p. 39– 69
  4. ↑ a b c d e f g h i j Galen B. Rathbun: Rhynchocyon petersi Black-and rufous Giant Sengi (Black-and rufous Elephant-shrew). In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 286-287
  5. ↑ a b c d e f Stephen Heritage: Macroscelididae (Sengis). 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. 206-234 (p. 228) ISBN 978-84-16728-08-4
  6. ^ Dieter Kock and William T. Stanley: Mammals of Mafia Island, Tanzania. Mammalia 73, 2009, pp. 339-352
  7. ↑ Norbert J. Cordeiro, Nathalie Seddon, David R. Capper, Jonathan MM Ekstrom, Kim M. Howell, Isabel S. Isherwood, Charles AM Msuya, Jonas T. Mushi, Andrew W. Perkin, Robert G. Pople and William T. Stanley: Notes on the ecology and status of some forest mammals in four Eastern Arc Mountains, Tanzania. Journal of the East Africa Natural History Society 94, 2005, pp. 175-189
  8. ^ William T. Stanley, Steven M. Goodman and Rainer Hutterer: Small Mammal Inventories in the East and West Usambara Mountains, Tanzania. 2. Families Soricidae (Shrews) and Macroscelididae (Elephant Shrews). Fieldiana: Life and EArth Sciences 4, 2011, pp. 18-33
  9. ↑ GH Swynnerton and RWHayman: A Checklist of the Land Mammals of the Tanganyika Territory and the Zanzibar Protectorate. Journal of the East African Natural History Society 20, 1951, pp. 274-392 (p. 283)
  10. ^ A b Stephanie Coster and David O. Ribble: Density and cover preferences of Black-and-rufous elephant-shrews (Rhynchocyon petersi) in Chome Forest Reserve, Tanzania. Belgian Journal of Zoology 135 (suppl.), 2005, pp. 175-177
  11. ↑ a b c d G. B. Corbet and J. Hanks: A revision of the elephant-shrews, Family Macroscelididae. Bulletin of the British Museum (Natural history) Zoology 16, 1968, pp. 47-111
  12. ^ A b c Andrew J. Baker, Kim Lengel, McCafferty, and Heidi Hellmuth: Black-and-rufous sengi (Rhynchocyon petersi) at the Philadelphia Zoo. Afrotherian Conservation 3, 2005, pp. 6-7
  13. ↑ Glover M. Allen and Arthur Loveridge: Reports on the scientific results of an expedition to the Southwestern Highlands of Tanganyika Territory. II. Mammals. Bulletin of the Museum of Comparative Zoology at Harvard College 75, 1933, pp. 47–140 (pp. 53–57) ( [2] )
  14. ^ Gea Olbricht: Longevity and fecundity in sengis (Macroscelidea). Afrotherian Conservation 5, 2007, pp. 3-5
  15. ↑ LJ Fourie, JS du Toit, DJ Kok and IG Horak: Arthropod parasites of elephant-shrews, with particular reference of ticks. Mammal Review 25, 1995, pp. 31-37
  16. ↑ a b Steven Heritage, Houssein Rayaleh, Djama G. Awaleh and Galen B. Rathbun: New records of a lost species and a geographic range expansion for sengis in the Horn of Africa. PeerJ 8, 2020, p. E9652, doi: 10.7717 / peerj.9652
  17. ^ Mike Perrin and Galen B. Rathbun: Order Macroscelidea - Sengis (Elephant-shrews). In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 258-260
  18. ^ HA Smit, B. Jansen van Vuuren, PCM O'Brien, M. Ferguson-Smith, F. Yang and TJ Robinson: Phylogenetic relationships of elephant-shrews (Afrotheria, Macroscelididae). Journal of Zoology 284, 2011, pp. 133-143
  19. ↑ Elizabeth J. Carlen, Galen B. Rathbun, Link E. Olson, Christopher A. Sabuni, William T. Stanley and John P. Dumbacher: Reconstructing the molecular phylogeny of giant sengis (Macroscelidea; Macroscelididae; Rhynchocyon). Molecular Phylogenetics and Evolution 113, 2017, pp. 150-160
  20. ↑ Guy Dollman: A new elephant shrew from the Island of Zanzibar. The Annals and magazine of natural history; zoology, botany, and geology 8 (10), 1912, pp. 130-131 ( [3] )
  21. ^ JV Barboza du Bocage: Notice sur une nouvelle espéce du genre Rhynchocyon, Peters. Jornal de sciencias mathematicas, physicas e naturaes, Academia Real das Sciencias de Lisboa 7, 1880, pp. 159–161 ( [4] )
  22. ^ Galen B. Rathbun: Eponyms in the Afrotheria: Who were the people that had Afrotheria species named after them? Afrotherian Conservation 9, 2012, pp. 5-6
  23. ^ Galen B. Rathbun and TM Butynski: Rhynchocyon petersi. The IUCN Red List of Threatened Species. Version 2015.2. ( [5] ); last accessed on June 28, 2015
  24. ^ Galen B. Rathbun and Laurie Bingaman Lackey: A brief graphical history of sengis in captivity. Afrotherian Conservation 5, 2007, pp. 7-8
  25. ↑ Zoo animal list ( [6] ), last accessed on June 15, 2015

Web links

Commons : Red-shouldered Proboscis  - Album with pictures, videos and audio files