Robust gold mole
| Robust gold mole | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Amblysomus robustus | ||||||||||||
| Bronner , 2000 |
The Robust Goldmull ( Amblysomus robustus ) is a mammalian species from the family of the golden moles , which in a narrowly restricted area of distribution in the Highveld of South Africa occurs. This largest representative of the copper gold mulle is not only characterized by its spindle-shaped body, which is typical of the family, with an externally invisible tail and ears, but also by its particularly powerful grave claws, which allows it to colonize much more solid ground than its relatives. It feeds mainly on invertebrates and lives solitary, but little information is available about the further way of life. The species was described in 2000 and its population is considered endangered.
features
Habitus
The robust gold mole is the largest representative of the copper gold mole ( Amblysomus ) and a medium-sized member of the gold mole . The head-torso length varies between 10.9 and 14.3 cm, the body weight varies from 61 to 98 g. There is a clear gender dimorphism , with regard to body size, certain overlaps with the Hottentot golden mole ( Amblysomus hottentotus ) and the highveld golden mole ( Amblysomus septentrionalis ) can occur. As with all gold molluscs, the body shows a typical spindle shape, an externally visible tail is not developed, and auricles are missing. The fur on the back is reddish-brown in color, it is slightly lighter on the sides. The belly is more orange in color. Stronger color breaks are not observed. Individual orange spots of color appear on the cheeks. The limbs are short and robust, they end in four rays at the front and five at the back. As with all gold mills, the claw of the third finger is particularly large. Here, however, the Hottentot gold mole and the Highveld gold mole can easily be separated from the robust gold mole, as the claw of the robust gold mole with a base width of 5.3 to 7.2 mm and a length of 14 to 17 mm is proportionally larger than that of the two other species. The rear foot length is 13 to 19 mm.
Skull and dentition features
The skull measures 27.2 to 32.0 mm in length and 16.6 to 20.4 mm in width. In terms of skull dimensions, the male animals are distinguished from the females by significantly larger values. In general, the skull has a relatively elongated shape; compared to the Highveld Goldmull, the rostrum is wider, but the palatal bone is narrower. The hyoid bone is characterized by a very massive structure. The teeth comprises 36 teeth, the dental formula is: . The canine and the anterior premolars have a sectorial design with two pointed cusps ( bicuspid ). The molars are tricuspid (with three cusps), the third posterior molar is usually missing. The lower molars each have a well-developed talonid. The upper row of teeth from the canine to the last molar is 6 to 7.6 mm long.
distribution
So far, the Robust Goldmull is only known from just under half a dozen locations in the Highveld , which are spread between the Steenkamps Mountains near eMakhazeni and Dullstroom in the South African province of Mpumalanga . According to current knowledge, the entire distribution area is less than 5000 km², but could also be more extensive. It extends at altitudes from 2000 to 2100 m above sea level. The species prefers montane grasslands and marshland with moist sandy soils, crumbly soils through to firmer clay substrates . In contrast, the animals avoid thin soils along rocky ridges, which may represent a barrier to spread, and waterlogged soils. In its very small area of distribution, the robust gold mole is relatively common and can also be found in gardens or orchards.
Way of life
The Robust Goldmull is solitary, there is no information about the social system. The main activity times extend over the afternoon and night. The animals bridge the hot hours of the day with a torpor . The sturdy physique with the extraordinary grave claws enable the robust gold mole to dig in heavier soils than the other representatives of the copper gold mole, who predominantly inhabit softer sandy soils. The underground burrows consist of two different systems of corridors: one running close to the surface of the earth, which is used for foraging, and a deeper one (20 to 80 cm below the surface of the earth), which is used for retreat and rest. In the latter, the tunnels end in larger living chambers. Some of the corridors also extend into dead trees. On the one hand, these may open up further food resources, on the other hand, they also offer protection in the event of heavy rainfall when the lower chambers are filled with water. The activity of the robust golden mole rat decreases in winter with the disappearance of the prey and the animals lapse into longer torpor phases lasting several days or move their activities deeper underground. Their main diet consists of invertebrates - mostly earthworms - and other soil-digging animals that they find at night. In captivity, they also eat mealworms and occasionally young mice, but they generally avoid carrion . Pregnant and lactating females have so far been observed in late summer and early autumn (March and April); the reproductive phase is therefore probably in the wetter summer.
Systematics
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Internal systematics of the gold mole according to Asher et al. 2010
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The robust gold mole is a species from the genus of the copper gold mole ( Amblysomus ). This represents a total of five members the most versatile representatives from the family of the golden moles are (Chrysochloridae), one endemic in Africa widespread group of smaller, ground grave forming mammals from the superiority of the Afrotheria . The main distribution area of the golden mole is southern Africa, only a few species are native to eastern or central Africa. With a few exceptions, they inhabit narrow habitats . Two ecological groups can be distinguished. For one part forms, in dry, partly semi-desert living areas, such as the Grant's golden mole ( Eremitalpa ) or chrysochloris ( Chrysochloris ). The others are adapted to open grass and savanna landscapes as well as forests, such as the copper gold mole, the giant gold mulle ( Chrysospalax ) or Arends' gold mole ( Carpitalpa ). The internal structure of the family has not yet been fully clarified. Often three subfamilies are kept apart, which 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. However, the structure of the gold mole based on skeletal anatomy cannot currently be traced in all cases by genetic findings. From a molecular genetic point of view, the closest relatives of Amblysomus are the genera Neamblysomus and Carpitalpa .
discovery
Until the mid-1990s, the representatives of the robust girdle mole were led within the Hottentot gold mole. In 1995, cytogenetic studies by Gary N. Bronner revealed that the Hottentot gold mole rat contained several species in its definition at the time. Accordingly, the population characterized for the actual Hottentot gold mole rat has 30 sets of chromosomes. Another from the area of Wakkerstroom in the South African province of Mpumalanga, on the other hand, has 34 pairs of chromosomes; it was then equated with the Highveld gold mole, which was scientifically introduced by Austin Roberts in 1913 . Another group came from the area around Dullstroom in the same province, which even has 36 chromosome pairs and was previously considered undescribed. In the following year Bronner was able to separate the individual groups of the Hottentot gold mole in a broader sense, also using morphometric characteristics. In 2000, Bronner described the Dullstroom population under the scientific name Amblysomus robustus . As a holotype , he chose an almost complete individual that he had collected in March 1990 in the Verloren-Vallei Natural Reserve Park 22 km northeast of Dullstroom in Mpumalanga, South Africa, at an altitude of 2150 m. The additional species robustus refers to the generally strong physique of the animals.
Hazard and protection
The previously known, not very extensive area of distribution of the robust gold mole is subject to serious human interference. Coal mines, which supply numerous power plants, which in turn form the backbone of the South African energy industry, have a major influence on the design of the region. At the moment, the mining areas do not directly threaten any of the locations where the robust gold mole has been detected. However, this cannot be ruled out in the future because of the increasing demand for energy due to increasing human settlement and general economic development. If the species is currently more widespread than known, individual populations could already be threatened. The transformation of the landscapes for arable farming and the tourist development of the region are of less importance for the robust gold mole, since the animals are considered adaptable and can survive in landscapes that have been changed by humans, albeit with a lower population density. Overall, the IUCN currently sees the robust gold mole population as “threatened” ( vulnerable ). The species occurs in the Verloren-Vallei Natural Reserve Park.
literature
- Gary N. Bronner: New species and subspecies of Golden Mole (Chrysochloridae: Amblysomus) from Mpumalanga, South Africa. Mammalia 64 (1), 2000, pp. 41-54
- Gary N. Bronner and Nigel C. Bennett: Amblysomus robustus Bronner, 2000 - Robust Golden mole. In: John D. Skinner and Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 20-21
- Gary N. Bronner: Amblysomus robustus Robust Golden-mole. 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. 231-232
- 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 (pp. 195–196) ISBN 978-84-16728-08-4
Individual evidence
- ↑ a b c d 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 e Gary N. Bronner and Nigel C. Bennett: Amblysomus robustus Bronner, 2000 - Robust Golden mole. In: John D. Skinner and Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 20-21
- ↑ a b c d Gary N. Bronner: Amblysomus robustus Robust Golden-mole. 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. 231-232
- ^ 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 (pp. 195–196) ISBN 978-84-16728-08-4
- ↑ a b C. Rampartab: Amblysomus robustus. The IUCN Red List of Threatened Species 2015. e.T62008A21284697 ( [1] ); last accessed on October 13, 2015
- ^ A b Robert J. Asher, Sarita Maree, Gary Bronner, Nigel C. Bennett, Paulette Bloomer, Paul Czechowski, Matthias Meyer and 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 and Jan Kalina (eds.): Mammals of Africa Volume I. Introductory Chapters and Afrotheria. Bloomsbury, London, 2013, pp. 223-225
- ^ 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 robustus in the endangered Red List species the IUCN 2015 Posted by: Gary Bronner, 2013. Accessed October 13, 2015.