Spotted elephant dog
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Spotted proboscis dog ( Rhynchocyon cirnei ) |
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| Rhynchocyon cirnei | ||||||||||||
| Peters , 1847 |
The spotted elephant dog ( Rhynchocyon cirnei ) is a species of mammal from the family of elephants (Macroscelididae). It has a comparatively large distribution area and occurs in Central and East Africa . Like all elephants, the species is characterized by its trunk-like elongated nose and slender limbs, with the hind legs being longer than the front legs. The animals inhabit forests in the flat and mountainous regions and are diurnal, but little information is available about their way of life. Due to the large distribution area and the sometimes variable coat design, the spotted elephant dog is assigned several subspecies, but their status is not guaranteed in all cases. The species was discovered and described by Wilhelm Peters during his trip to Africa in the 1840s . Their population is currently considered to be less threatened.
features
Habitus
The spotted trunk dog is a small to medium-sized representative of the trunk dog. The total length varies from 43.9 to 50.9 cm. According to investigations of around 20 individuals from different areas of the distribution area, the head-trunk length is 22.9 to 27.3 cm and the tail length 19.6 to 24.6 cm. The tail thus reaches about 90% of the length of the rest of the body. The weight could only be determined from a few animals and varied between 320 and 420 g. Another seven individuals from north-eastern Mozambique were 51.3 to 55.3 cm long with a tail length of 23.9 to 26.3 cm and weighed 440 to 630 g. In terms of physique, the spotted trunk dog with the trunk-like elongated nose and the short front and long hind legs resembles the other trunk dogs. The back fur is colored very variably, the basic color corresponds to a yellow to dark brown, partly with a reddish tinge. On the back there are six strips arranged in rows (three on each side), which extend from the front third or half of the trunk to the base of the tail. The formation of the stripe pattern can also be very varied. The two median strips usually show no interruption and are often black or maroon. The outer ones consist of a series of spots that appear alternately light or dark or evenly colored. In populations with a very dark basic color, the stripes are rather indistinct. The belly is predominantly whitish in color. The almost hairless tail has a striking white tip. A gray-yellow to cream-colored tint dominates the head. The ears stand erect and bare, their length is 27-31 mm. The trunk-like nose is flexible and very sensitive to touch. The front and rear legs are yellowish-brown in color, the feet each have four rays with strong claws. The rear foot becomes 63 to 76 mm long.
Skull and dentition features
The skull reaches a length of 62.2 to 70.8 mm, the greatest width between the zygomatic arches is 33.5 to 38 mm. The bit consists of 34 to 36 teeth, the dental formula is: . A secondary sexual dimorphism can be recognized by the shape of the respective upper canine . In males this is between 3.3 and 6.3 mm long, in females 1.7 to 5.9 mm. The length of the upper row of teeth varies between 23.8 and 28.7 mm.
distribution and habitat
The spotted elephant dog is found in central and east Africa . The distribution area includes in the north the southeastern part of the Democratic Republic of the Congo , southern Tanzania and northeastern Zambia . Here, the southwest border could be extended through field research since 2015 to the Mutinondo Wilderness . It extends further south from Malawi to northern Mozambique with the Zambezi as a natural barrier. The species has been observed in southern Tanzania and Malawi up to an altitude of 2280 m. Compared to the other elephants, the spotted elephant has a relatively large distribution area. It includes the rainforest regions as well as the Zambezi woodland zone and parts of the Somalia-Maasai bush zone. The preferred habitat is found in the forests of the plains, but also in mountain forests and bank thickets. The canopy should be closed and the soil should be covered with a thick layer of leaves. In general, the species is considered to be relatively common, but no more detailed information is available.
Way of life
Little information is available about the way of life of the spotted elephant dog, despite its widespread distribution, but it may be similar to that of the better studied golden elephant dog ( Rhynchocyon chrysopygus ). It is diurnal and soil dwelling. It retreats in nests to sleep. These consist of a small hollow dug into the ground, which the animal lines with plant material, some of which bulges like a dome. Like other elephant dogs, it does not create paths through the vegetation. The majority of the known sightings relate to singular individuals, couples have only rarely been observed. The main food is likely to consist of insects , a single gastric remnant examined so far was composed of beetles , hymenoptera and larvae of two-winged animals . Most of the offspring consist of only one young per litter, but females with two fetuses have been observed in individual regions such as Zambia or Malawi .
The black and white hat snake , the common chimpanzee and the African golden cat appear on known predators . The stain pattern on the back may have a camouflaging effect. Ticks of the genus Ixodes , fleas of the genus Chimaeropsylla and two-winged birds of the genus Cordylobia have been identified as external parasites . In addition, the protozoon Sarcocystis has been described as an internal parasite in the spotted proboscis dog.
Systematics
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Internal systematics of elephants according to Heritage et al. 2020
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The spotted proboscis is a species from the genus of the proboscis ( Rhynchocyon ), which includes four other species. The elephants in turn belong to the family of the elephants (Macroscelididae) within the order of the same name (Macroscelidea). The representatives of the elephants are smaller mammals that are endemic to Africa . A total of six genera and two subfamilies can be assigned to them. The proboscis are the only members of the subfamily Rhynchocyoninae, which is thus monotypical . They represent the largest forms within the elephants, whose preferred habitats consist of dense and moist forests. The second subfamily, the Macroscelidinae , includes the elephant shrews ( Elephantulus ), the proboscis ( Petrodromus ) and the genera Macroscelides , Galegeeska and Petrosaltator . The species in this group are characterized by their significantly smaller growth, and they also inhabit predominantly dry to sometimes desert-like landscapes. Molecular genetic studies have shown that the two subfamilies separated from each other in the Lower Oligocene , about 32.8 million years ago. Within the genus Rhynchocyon , greater diversification began in the late Middle Miocene , about 9.7 million years ago.
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Internal systematics of the proboscis dogs according to Carlen et al. 2017
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It is partly assumed that the red-shouldered proboscis dog ( Rhynchocyon petersi ) and the golden proboscis dog ( Rhynchocyon chrysopygus ) are to be regarded as daughter species of the spotted proboscis pooch due to the occasional appearance of an inconspicuous pattern of spots on the back of individual individuals . The species is very varied, a total of five subspecies are provisionally distinguished:
- R. c. cirnei Peters , 1847; Mozambique , basic color grayish black and yellow with a slightly reddish brown tinge on the torso and thighs; Spots chestnut brown, the two median stripes running from the base of the tail to a little over the center of the back, the second and third stripes are faint or barely recognizable.
- R. c. hendersoni Thomas , 1902; known only from Livingstonia in northern Malawi ; Basic tone very dark; the two median stripes black, reaching from the base of the tail to over two thirds of the back; second and third stripes with alternating light and dark spots, colored red-brown between these stripes; Tail two-colored in the front part.
- R. c. macrurus Günther , 1881; Coastal forests of Tanzania , possibly also northern Mozambique; variable, basic color reddish brown to yellowish brown, the two central stripes chestnut brown and clearly visible, the second stripe with lighter spots, the third stripe barely visible; in the case of inland forms, the pattern of spots is often easier to recognize than in the case of representatives directly from the coastal areas.
- R. c. reichardi Reichenow , 1886; northern Malawi, northeastern Zambia , southeastern Democratic Republic of the Congo, and southwestern Tanzania; Basic color gray-black to creamy; the two median stripes black, reaching from the base of the tail to over two thirds of the back; second and third row alternating light and dark spots, both stripes partially merging; Two-colored tail in the front two thirds.
- R. c. shirensis Corbet & Hanks , 1968; southern Malawi and northern Mozambique; Basic color gray-black to creamy, hardly yellowish, slightly reddish brown on the thigh; the two median strips running from the base of the tail to a little over the middle of the back, very dark brown; second and third stripes with alternating light and dark spots.
Some subspecies may be considered clinical . The dark elephant dog ( Rhynchocyon stuhlmanni ) has long been the sixth subspecies of the spotted elephant dog. Due to the distribution area separated from the other subspecies and the clearly different external appearance, however, some scientists suspected an independent species character as early as the late 1960s. This was confirmed in 2017 with the help of molecular genetic studies. The status of R. c. shirensis should be confirmed as a subspecies, since this was previously partially identical to R. c. cirnei has been classified.
The first scientific description of the spotted elephant dog comes from Wilhelm Peters in 1847. As a basis he used two individuals, a male and a female, which he himself during his trip through large parts of southern Africa in 1842 and 1848 near Quelimane in northern Mozambique. The region is considered to be the type area of the species. During his stay in northern Mozambique, Peters was a guest at Mr. Cirne's estate at Quelimane. Cirne accompanied the naturalist on expeditions into the surrounding area, and Peters also owed him the discovery of the spotted elephant dog. Therefore, in honor of its host, he gave the animal the scientific name Rhynchocyon cirnei . The specific epithet is often associated with Manuel Joaquim Mendes de Vasconcelos e Cirne , a former governor of Mozambique when it was still a Portuguese colony , but Manuel JM Cirne died in 1832. After his return to Germany, Peters wrote a much more extensive description of the Spleckten Rüsselhündchens, which he published in 1852 in his paper Scientific trip to Mossambique . Of the two captured individuals, one, the female, was sent to the Berlin Natural History Museum ; Peters exchanged the male with the museum in Leiden at the request of Coenraad Jacob Temminck .
Threat and protection
The main threat to the existence of the spotted elephant dog is the destruction of the forests and with it the loss of suitable habitat. The subspecies R. c. Are particularly affected . hendersoni , which is restricted to some isolated mountain forests in Malawi, and R. c. cirnei , whose distribution area includes a limited area in the north of Mozambique. This may also apply to R. c. macrurus , which is also likely to occur in northern Mozambique. Hunting the animals as a food resource, for example by the nyanja in East Africa, can also have a negative impact locally . Since the spotted elephant dog has a much larger distribution area compared to the other elephant dog, the IUCN currently lists the species as " near threatened ". But it is likely that with further ongoing deforestation of the threat status to "at risk" ( vulnerable ) must be increased. Special protective measures do not exist for the spotted elephant dog, but it could benefit from conservation efforts for antelopes and primates .
The spotted elephant dog is seldom kept in zoos, the only European owner is currently the Pilsen Zoo in the Czech Republic , which took over the stock from the Berlin Zoo in 2015 .
literature
- 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 doi: 10.1016 / j.ympev.2017.05.012
- 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. 227) 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 cirnei Checkered Giant Sengi (Checkered 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. 285-286
Individual evidence
- ↑ a b 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
- ^ A b c Peter GR Coals and Galen B. Rathbun: The Taxonomic Status of Giant Sengis (Genus Rhynchocyon) in Mozambique. Journal of East African Natural History 101 (2), 2013, pp. 241-250
- ↑ 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
- ↑ a b c d e f g Galen B. Rathbun: Rhynchocyon cirnei Checkered Giant Sengi (Checkered 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. 285-286
- ↑ a b c d 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. 227) ISBN 978-84-16728-08-4
- ^ Frank Willems: The occurrence of Checkered Giant Sengis (Rhynchocyon cirnei) in Mutinondo Wilderness and their distribution in Zambia. Afrotherian Conservation 12, 2016, pp. 23-28
- ↑ Frank Willems: Presence of Checkered Giant Sengi (Rhynchocyon cirnei) at Shiwa N'gandu in northern Zambia. Afrotherian Conservation 13, 2017, pp. 3–6
- ^ A b 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) ( [1] )
- ^ A b Barbara Lawrence and Arthur Loveridge: Zoological results of a fifth expedition to East Africa. I. Mammalia from Nyasaland and Tete. Bulletin of the Museum of Comparative Zoology at Harvard College 110, 1953; Pp. 1–80 ( [2] )
- ↑ 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
- ^ IF Keymer: Blood protozoa of insectivores, bats and primates in Central Africa. Journal of Zoology 163, 1971, pp. 421-441
- ↑ 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
- ^ 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
- ^ 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
- ↑ a b c 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
- ^ Wilhelm Peters: A new mammal species from the orders of the insect eater. Report on the negotiations of the Royal Prussian Academy of Sciences that were suitable for publication in 1847, pp. 36–38 ( [3] )
- ^ A b Wilhelm Peters: Scientific trip to Mossambique: carried out on the orders of His Majesty the King Friedrich Wilhelm IV in the years 1842 to 1848. Berlin, 1852, pp. 1–205 (pp. 100–110) ( [4] )
- ^ 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
- ^ Galen B. Rathbun: Rhynchocyon cirnei. The IUCN Red List of Threatened Species. Version 2015.2. ( [5] ); last accessed on July 12, 2015
- ↑ zoo animal list ; last accessed on June 15, 2015
Web links
- Rhynchocyon cirnei in the endangered Red List species the IUCN 2006. Posted by: GB Rathbun, 2006. Accessed July 12, 2015.
- California Academy of Sciences: Photo of a spotted elephant dog
- Information and illustration on Animal Diversity Web