Highveld gold mole
| Highveld gold mole | ||||||||||||
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| Scientific name | ||||||||||||
| Amblysomus septentrionalis | ||||||||||||
| Roberts , 1913 |
The highveld gold mole ( Amblysomus septentrionalis ) is a type of gold mole that occurs only in the highveld in the eastern part of South Africa and is there limited to around a dozen scattered localities. It is a relatively large representative of the copper gold mulle and, like its relatives, is characterized by a characteristic, spindle-shaped body with an externally invisible tail and ears and by powerful grave claws. With the help of its large claws, it can colonize harder and heavier soils than other gold mole. The main food of the solitary animal consists of invertebrates , about the further way of life is only sparse information available. The Highveld Goldmull was first described in 1913, but it has only been recognized as an independent species since the mid-1990s. The stock is considered to be at low risk.
features
Habitus
The highveld gold mole represents a medium-sized representative of the gold mole and the second largest representative of the copper gold mole ( Amblysomus ) after the robust gold mole ( Amblysomus robustus ). The head-torso length is 10.5 to 14.5 cm, the weight ranges from 52 to 86 g. A sexual dimorphism is pronounced and is indicated by larger average male. In addition, there is a clinical size variation in relation to individual populations with different height distribution. As with all other golden mullets, there are no externally visible ears and a tail, and the body is spindle-shaped. In terms of fur color, the species is similar to the robust and Hottentot gold mole ( Amblysomus hottentotus ). It is dark reddish brown on the back, but turns into a lighter reddish brown on the flanks. The belly is pale brown to orange in color. The long hairs have a yellowish base, but near the tip they are tinted dark gray. Individual pale yellowish spots appear on the cheeks, which run laterally to behind the eyes hidden under the skin. The sturdy limbs end in four rays at the front and five at the back. The claws of the hands are strongly developed, especially the claw of the third ray is particularly large. It has a base width of 5.3 to 6.6 mm and a total length of 14 to 15.7 mm, but compared to that of the Robust Goldmull it is relatively smaller. The rear foot length is 12 to 20 mm.
Skull and dentition features
The skull becomes between 26.2 and 30.5 mm long and between 16.1 and 19.5 mm wide. The rostrum of the Highveld-Goldmull is narrower than that of the Robust Goldmull, but the palate is wider. As with the other copper gold Mullen the teeth includes 36 teeth, the dental formula is: . The rearmost molar is mostly missing. Well-developed talonids are found on the lower molars. The anterior premolar has two small cusps ( bicuspid or sectorial ). The upper row of teeth from the canine tooth to the second molar tooth has a length of 6.2 to 7.4 mm.
distribution
The highveld gold mole is endemic to southern Africa . It occurs in the South African province of Mpumalanga in the east from Wakkerstroom to Ermelo and Barberton and in the province of Free State to the west from Heilbron to Parys . It is possible that individual populations are also represented in northern Swaziland , for example near Mbabane , as congruent skull features suggest, as well as in the South African Harrismith , but genetic evidence is still lacking . An individual was caught in the Drakensberg Mountains in the municipality of uMngeni in the province of KwaZulu-Natal at the turn of the year 2015 to 2016 . Overall, the species is clearly known from a dozen localities that spread over an area of around 2500 km². The distribution area is in the high elevations of the Highveld between 1600 and 1800 m above sea level. The preferred habitats consist of grasslands and the edges of marshland . The Highveld Goldmull is mainly bound to loose soils in valleys and on valley slopes, where it occurs partly sympathetically with the Wire-haired Goldmull ( Chrysospalax villosus ). In addition, he also colonizes river valleys with thickets of the rose family Leucosidea sericea , but generally avoids scrub on steep river banks and rocky ridges. Here it is replaced by Sclater's gold mole ( Chlorotalpa sclateri ). The Highveld Goldmull was also observed in gardens, plantations and golf courses. The species is considered to be relatively common, studies at Wakkerstroom suggest a population density of three individuals per hectare , the total population is likely to be over 10,000 individuals.
Way of life
The way of life of the Highveld Goldmull has been little researched. The animals live solitary, beyond that nothing is known about their social behavior. With their strong claws on the forefoot, they can dig in on average heavier soils than other representatives of the golden mole. Individual individuals use a two-story tunnel system. In search of food, the Highveld Goldmull moves in corridors close to the surface. Deeper tunnels, which run 10 to 50 cm below the surface, connect individual living rooms lined with grass. The main activity takes place at night and ends shortly after sunrise. The animals spend the day in a torpor that lasts until the afternoon. In winter they retreat to the lower corridors.
The diet consists of invertebrates , mostly earthworms or insect pupae . There is also little data available on reproduction. It may occur all year round, but pregnant females have often been observed during the wetter summer months (November to March). A litter consists of one or two young animals that grow up as nestlings in a grass-covered nest. The natural predators include the white-necked weasel as well as domestic dogs and domestic cats . Occasionally, remnants of the Highveld mullet are also found in the crests of the barn owl . This indicates that the species can sometimes be found on the surface, possibly when the underground tunnels are flooded as a result of heavy rain.
Systematics
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Internal systematics of the gold mole according to Asher et al. 2010
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The Highveld-Goldmull is a species from the genus of the coppergoldmulle ( Amblysomus ), which includes a total of five members. The copper gold mulle thus form the most varied group of the gold mole family (Chrysochloridae). The family lives endemic in Africa and includes smaller, ground grave mammals from the superiority of the Afrotheria . Mainly the gold mole inhabit southern Africa, only a few species are also found in eastern or central Africa. Due to their special way of life, the habitats of the individual species are very limited with only a few exceptions. In principle, two ecological groups can be distinguished. On the one hand, there are forms of dry, sometimes semi-desert adapted regions, including the Grant's golden mole ( Eremitalpa ) or chrysochloris ( Chrysochloris ) belong. The second group consists of inhabitants of open grass and savannah landscapes as well as forests, such as the copper gold mole, the giant gold mole ( Chrysospalax ) or Arends' gold mole ( Carpitalpa ). The internal structure of the family has not yet been fully clarified. There are often three subfamilies that differ in the construction of the hammer in the middle ear : the Amblysominae with a normally built malleus, the Chrysochlorinae with a greatly elongated head of the malleus and the Eremitalpinae with a spherically inflated head of the malleus. In some cases, however, the last two are combined into a subfamily, the Chrysochlorinae. This subdivision of the golden mole, based on features of the skeletal anatomy, has not yet been fully confirmed by genetic findings. According to molecular genetic studies, Neamblysomus and Carpitalpa belong to the immediate family of Amblysomus .
There are noticeable differences in the dimensions of the skull between the individual populations of the Highveld Gold Mole. The number of animals examined has so far been too small to be able to work out general trends or even different subspecies. The first scientific description of the species was made in 1913 by Austin Roberts under the name Amblysomus corriae septentrionalis and thus within the Fynbos gold mole rat ( Amblysomus corriae ). Roberts carried out the description on a single, pregnant female from Wakkerstroom, which he had already dug out of a mound in mid-September 1909. The area is considered a type region of the species. In the following period, the Highveld Goldmull was partially incorporated into the Hottentot Goldmull ( Amblysomus hottentotus ) and added to the subspecies Amblysomus hottentotus iris (which, however, also had species status). In 1989 it was possible to show for the first time by means of genetic analyzes that populations with different karyotypes occur within the copper gold mole . Accordingly, the examined individuals of the Hottentot gold mole had a total of 30 pairs of chromosomes, while an animal from Wakkerstroom in the South African province of Mpumalanga had 34. Further genetic studies from the mid-1990s could not only confirm this, but also added a population from Ermelo in the same province to the group with a 34-pair chromosome set. Further morphological studies showed that in terms of skull dimensions, the populations from Wakkerstroom and Ermelo formed a closed unit compared to the Hottentot and Fynbos golden mole. For this reason, Gary N. Bronner raised the Highveld Goldmull to species level.
Hazard and protection
The greatest threat to the existence of the Highveld Goldmull is the changes in the landscape as a result of coal mining in the region. This supplies numerous power plants , which in turn maintain the country's energy supply. Since the increasing population and the general economic development can be expected to have a higher energy demand in the future, it can also be assumed that the high-level gold mole will face an increasing threat. On the other hand, the overprinting of settlement areas by agriculture and cattle breeding is of subordinate importance, since the animals can also survive in such human landscapes. Hunting by domestic dogs and cats plays a role locally, as is pursuit and displacement by horticulturists. The IUCN classifies the Highveld-Goldmull as "potentially threatened" ( near threatened ) and assumes a decline in the population. It has not yet been represented in any designated protected area.
literature
- Gary N. Bronner, Nigel C. Bennett: Amblysomus septentrionalis Roberts, 1913 - Highveld Golden mole. In: John D. Skinner, Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 17-18.
- Gary N. Bronner: Amblysomus septentrionalis Highveld Golden-mole. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold, Jan Kalina (Eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 232-233.
- William A. Taylor, Samantha Mynhardt and Sarita Maree: Chrysochloridae (Golden moles). 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. 180–203 (p. 196) ISBN 978-84-16728-08-4
Individual evidence
- ↑ a b c d e f g Gary N. Bronner, Nigel C. Bennett: Amblysomus septentrionalis Roberts, 1913 - Highveld Golden mole. In: John D. Skinner, Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 17-18.
- ↑ a b c d e f Gary N. Bronner: Amblysomus septentrionalis Highveld Golden-mole. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold, Jan Kalina (Eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 232-233.
- ^ Gary N. Bronner: New species and subspecies of Golden Mole (Chrysochloridae: Amblysomus) from Mpumalanga, South Africa. Mammalia 64 (1), 2000, pp. 41-54.
- ^ A b c d William A. Taylor, Samantha Mynhardt and Sarita Maree: Chrysochloridae (Golden moles). 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. 180–203 (p. 196) ISBN 978-84-16728-08-4
- ↑ Felicity Nonsimiso Simelane, Themb'alilahlwa AM Mahlaba, Julie Teresa Shapiro, Duncan MacFadyen and Ara Monadjem: Habitat associations of small mammals in the foothills of the Drakensberg Mountains, South Africa. Mammalia, 2017 ( [1] )
- ↑ a b C. Rampartab: Amblysomus septentrionalis. The IUCN Red List of Threatened Species 2015. e.T62009A21284057. ( [2] ); last accessed on October 18, 2015
- ^ A b Robert J. Asher, Sarita Maree, Gary Bronner, Nigel C. Bennett, Paulette Bloomer, Paul Czechowski, Matthias Meyer, Michael Hofreiter: A phylogenetic estimate for golden moles (Mammalia, Afrotheria, Chrysochloridae). MC Evolutionary Biology 10, 2010, p. 69 doi: 10.1186 / 1471-2148-10-69
- ^ Alberto M. Simonetta: A new golden mole from Somalia with an appendix on the taxonomy of the family Chrysochloridae (Mammalia, Insectivora). Monitore Zoologico Italiano NS Supplement 2, 1968, pp. 27-55.
- ^ Gary N. Bronner: Family Chrysochloridae Golden-moles. In: Jonathan Kingdon, David Happold, Michael Hoffmann, Thomas Butynski, Meredith Happold, Jan Kalina (Eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 223-225.
- ↑ Austin Roberts: The collections of mammals in the Transvaal Museum registered uo to the 31st March, 1913, with descriptions of new species. Annals of the Transvaal Museum 4 (2), 1913, pp. 65-107.
- ↑ E. Capanna, MV Civetilli, GC Hickman, E. Nevo: The chromosomes of Amblysomus hottentotus (Smith 1829) and A. iris Thomas & Schwann 1905: a first report for the golden moles of Africa (insectivora Chrysochloridae). Tropical Zoology 2, 1989, pp. 1-12.
- ^ Gary N. Bronner: Cytogenetic Properties of Nine Species of Golden Moles (Insectivora: Chrysochloridae). Journal of Mammalogy 76 (3), 1995, pp. 957-971.
- ^ Gary N. Bronner: Geographic patterns of morphometric variation in the Hottentot golden mole, Amblysomus hottentotus (Insectivora: Chrysochloridae). A multivariate analysis. Mammalia 60 (4), 1996, pp. 729-751.
Web links
- Amblysomus septentrionalis in the endangered Red List species the IUCN 2015 Posted by: C. Rampartab, 2013. Accessed October 18, 2015.