Visagies Goldmull

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Visagies Goldmull
Systematics
Superordinate : Afrotheria
without rank: Afroinsectiphilia
Order : Tenrecus (Afrosoricida)
Family : Gold mole (Chrysochloridae)
Genre : Cape gold mole ( Chrysochloris )
Type : Visagies Goldmull
Scientific name
Chrysochloris visagiei
Broom , 1950

Visagie's gold mole ( Chrysochloris visagiei ) is a little researched mammal from the genus of the Cape gold mole ( Chrysochloris ) in the family of the gold mole (Chrysochloridae). So far, only one specimen is known, the origin of which was given in the first description published in 1950 with Gouna in the South African province of North Cape . The region belongs to the Karoo and consists of dry, stony terrain. Neither the location nor the species status are currently considered certain.

features

Visagie's gold mole is very similar to the Cape gold mole ( Chrysochloris asiatica ). The only known specimen, a female, has a head-to-trunk length of 10.6 cm, no weight is given. It shows the typical spindle-shaped body of the other gold mole, externally visible ears and the tail are missing. The fur is light yellowish-brown-olive on the back, the individual hairs are characterized by a gray color with fawn-brown tips. The underside has a somewhat lighter, mostly gray tint with a slight yellowish-brown tinge. The undercoat is colored slate gray. The face looks a little lighter than the rest of the body. The strong forefeet ends in four rays that have well-developed grave claws. The longest is formed on the central ray (ray III), it is 4.1 mm wide at the base. Shorter claws are formed on the two inner beams, the first being even smaller than the second. On the outer (fourth) finger there is only a clearly receded claw. The five-pointed hind feet are 12 mm long.

The skull measures 22.8 mm in length and 17.7 mm in width. In its short and wide shape, it largely corresponds to that of the Cape Goldmull. As with these, there is a distinct bony bulge on the temporal fossa that accommodates the head of the hammerbone in the middle ear. This is typical of the Cape Goldmull, which is elongated like a club, but with Visagies Goldmull it has a relatively wider shape, so that the length of the head only doubles the width (with the Cape Goldmull the length-to-width ratio is 3: 1) . The dentition consists of 40 teeth with the following dental formula together: . The rearmost, third molar is reduced in size, but, like the anterior molars, has a tricuspid chewing surface pattern. There is no talonid on the lower molars. The length of the upper row of teeth from the canine to the last molar is 6.5 mm, measured from the innermost incisor 10 mm.

Site and discovery

Distribution map of Visagies Goldmull

Visagie's Goldmull was first scientifically described by Robert Broom in 1950 . The holotype , a fully grown female, comes from a farm near Gouna around 86 km east of Calvinia in the South African province of North Cape , according to him . There he was picked up by Captain Guy Chester Shortridge in 1949 . Broom awarded the type epithet visagiei in honor of IHJ Visagie, the owner of the farm on which the type specimen was discovered. The indicated area belongs to the dry Nama-Karoo and consists of a pebbly slate soil, which seems unsuitable as a habitat for gold mole. During two independent excursions, one of them in 2002, employees of the Kaffrarian Museum (now the Amathole Museum ) failed to track down new specimens of Visagie's gold mole. In the cultivated stretches of land along the banks of the Great Fish and Renoster Rivers , no signs of gold mole activity could be detected, and local farmers did not remember any sightings of such animals. Therefore, in addition to a general assumption that Visagie's gold mole was locally extinct, there are several possibilities for the absence of this particular form of gold mole: either the type specimen was transported to the known find area by humans or natural processes such as flooding of the Renoster River, or there is a mix-up on the part of Brooms and the information about the find region is incorrect. With the latter assumption, Gouna Forest near Knysna in the Eastern Cape Province would be an alternative . So far, however, no field studies have been carried out there. A third approach consists in the fact that the type specimen does not represent an independent species, but a Cape Goldmull, which has migrated to the region from a more suitable habitat in the west; probably via the Great Fish River system.

Systematics

Visagie's gold mole is currently regarded as an independent species from the genus Cape gold mole ( Chrysochloris ). The Cape Gold Mole also includes the Cape Gold Mole ( Crysochloris asiatica ) and Stuhlmann's Gold Mole ( Crysochloris stuhlmanni ). The genus in turn forms part of the family of the golden mole (Chrysochloridae), small, soil-digging mammals from the parentage of the Afrotheria . The golden mole is endemic to Africa , with a large part of the species being native to the southern part of the continent, a few also live in the eastern or central part. The animals inhabit dry to desert-like landscapes as well as open grass and savannah regions and forests. Due to their subterranean way of life, they represent habitat specialists with often very limited habitats. Within the gold mole, two to three subfamilies are endured - whether enlarged or not - based on the shape of the hammer in the middle ear . However, this can only be partially understood with the help of molecular genetic studies. With regard to the Cape Gold Mulle, however, both the skeletal anatomical and the genetic data point to a closer relationship with Cryptochloris . The representatives of both genera are characterized by a club-like elongated head of the malleus, which is more pronounced in Chrysochloris than in Cryptochloris .

The independence of Visagies Goldmull has been the subject of several specialist discussions in the history of research. Already three years after the first description, the gold mole representative was listed by John Ellerman as a subspecies of the Cape gold mole, which Alberto M. Simonetta confirmed 15 years later, in 1968 . Subsequent authors, however, saw Visagie's gullet as a valid species again, such as Jurgens AJ Meester in the 1970s and Francis Petter in the 1980s. The noticeably wide head of the hammer in the middle ear is often used as a distinguishing feature of the Cape Goldmull, but is within the range of variation of the latter. For this reason it is entirely possible that Visagies gold mole is just a special form of the Cape gold mole. However, additional copies must be used to support this view.

status

The IUCN lists Visagies Goldmull in the category “insufficient data” ( data deficient ). Extensive agriculture has dramatically changed the habitat in the assumed type locality . However, the effects of these transformations cannot be assessed until the uncertainties regarding the exact origin of the type specimen have been eliminated and / or the habitat requirements of this species are known.

literature

  • Gary N. Bronner: Family Chrysochloridae. In: Gus Mills and Lex Hes (Eds.): The Complete Book of Southern African Mammals. Struik Publishers, Cape Town, 1997, p. 56 ISBN 978-094-743-055-9
  • Gary N. Bronner: Chrysochloris visagiei Visagie's 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, p. 246
  • Gary N. Bronner and Nigel C. Bennett: Chrysochloris visagiei Broom, 1950 - Visagie's golden mole. In: John D. Skinner and Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 7-8
  • 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. 201) ISBN 978-84-16728-08-4

Individual evidence

  1. ^ A b c Robert Broom: Some further advances in our knowledge of the Cape golden moles. Annals of the Transvaal Museum 21, 1950, pp. 234-241
  2. ^ A b c d Gary N. Bronner: Chrysochloris visagiei Visagie's 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, p. 246
  3. ^ A b c Gary N. Bronner and Nigel C. Bennett: Chrysochloris visagiei Broom, 1950 - Visagie's golden mole. In: John D. Skinner and Christian T. Chimimba (Eds.): The Mammals of the Southern African Subregion. Cambridge University Press, 2005, pp. 7-8
  4. ^ A b 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. 201) ISBN 978-84-16728-08-4
  5. ^ A b c Gary N. Bronner: Chrysochloris visagiei. The IUCN Red List of Threatened Species 2015. e.T4812A21287855 ( [1] ); last accessed on March 26, 2016
  6. ^ Gary N. Bronner: Family Chrysochloridae. In: Gus Mills and Lex Hes (Eds.): The Complete Book of Southern African Mammals. Struik Publishers, Cape Town, 1997, p. 56
  7. ^ A b 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
  8. ^ 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
  9. ^ 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
  10. ^ Jurgens AJ Meester: South African Red Data Book - Small Mammals. A Report of the Committee for Terrestrial Biology. National Program for Environmental Sciences. South African National Scientific Programs Report. No. 11, Council for Scientific and Industrial Research, Pretoria, 1976, p. 13 ( [2] )
  11. ^ F. Petter: Remarques sur la systematique des Chrysochlorides. Mammalia 45 (1), 1981, pp. 49-53

Web links

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