Karasbergia methueni
| Karasbergia methueni | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Karasbergia | ||||||||||||
| Hewitt , 1913 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Karasbergia methueni | ||||||||||||
| Hewitt , 1913 |
Karasbergia methueni is a common in Namibia and South Africa scorpion of the monotypic genus Karasbergia in the family Buthidae .
features
Karasbergia
The genus Karasbergia differs from all other genera of the scorpions by the combination of the following features: number and distribution of the trichobothria and the shape of the hemispermatophores , spurs only on the tibiae of the third and fourth pairs of legs and a pentagonal sternum of type 1 that is longer than wide is.
Karasbergia also differs from all other genera of the Buthidae family by the presence of only two pairs of fully developed lateral ocelles , a third, severely stunted pair is only occasionally present. The carapace , chelae, and patella of the pedipalps, and the upper and outer surfaces of the legs are keeled. The mesosomal tergites have only a weak medial keel. The segments of the metasoma each have only indicated dorsal keels, which consist of a few granules. The first three segments have no stridulation areas on the surface. All segments of the metasoma and the telson have laterally, the fourth and fifth segments and the telson also on the abdomen, depressions from each of which a seta of 50 micrometers to one millimeter in length protrudes. The telson does not have a subacular tubercle.
Karasbergia methueni
Karasbergia methueni is a very small scorpion, the length of adult specimens rarely exceeds 25 millimeters. Carapace, Tergite and Metasoma are beige-yellow to ocher-yellow in color. Chelicerae , pedipalps, legs, sternite and telson are cream to chamois and a little lighter than carapace and metasoma. The comb organs are pale yellow and the poison sting black.
The carapace has an evenly coarse-grained surface. The median ocelles are in front of the middle of the carapace. They are significantly larger than the lateral ocelles. The surfaces of the first six tergites of the mesosoma are smooth and shiny in female scorpions, and increasingly coarse-grained from front to back in males. The seventh tergite is coarse-grained over its entire surface and, like the first six tergites, has weakly pronounced median keels. The sternites are smooth and shiny, only the seventh has a coarse grain on parts of its surface. The sternum is type 1 and is slightly longer than wide and pentagonal, without a furrow in the middle and with a heart-shaped depression at the base. The comb organs have 13 to 17 teeth in male scorpions and 11 to 13 teeth in females. The genital perculum is completely divided in the longitudinal direction, the genital opening has no papillae in either sex.
The first segment of the metasoma is about as long as it is wide, the others are increasingly elongated. There are only a few keels, most of which are only hinted at by a few granules. The three anterior segments have no stridulation surfaces. The dorsal surfaces of female scorpions can be smooth, otherwise they have a dense, coarse grain. The ventral surfaces of the first four and anterior halves of the fifth segment are dense and coarse-grained. The telson is spherical and elongated when viewed from the side, with a flattened dorsal surface. It is only slightly narrower than the fifth metasomal segment and has no subacular tubercle. The venomous sting is short, about one-third the length of the telson, and sharply curved.
The chelae of the Pedipalps are short and strong. Your femora have a finely and evenly grained surface on all sides. In male scorpions the patella are fine and evenly grained on the upper side and inside, in female scorpions only inside. Only the tibia of the posterior pairs of legs have spinous processes. The entire surface of the femora and parts of the undersides of the patella are finely grained, the other leg links have a smooth surface.
Different populations of Karasbergia methueni differ markedly in the hairiness of Metasoma and Telson. Specimens with exceptionally high setae populations have been found to live in sandy habitats. Despite their very different external appearance, they are not granted a species status; the transition to the almost hairless populations is fluid. Male scorpions have a longer metasoma relative to their body length and appear slimmer and elongated overall. The sexes also differ in the extent of the granulation of the mesosomal tergites, the metasoma, and in the number of teeth of the comb organs. The comb organs can also be used to determine the sexes of juvenile and subadult scorpions.
distribution and habitat
The Terra typica of Karasbergia methueni is the Farm South Narudas in the eponymous for the genus Karas Mountains . It is located in the Karasburg constituency of the Namibian region of ǁKaras ( 27 ° 22 ′ 0 ″ S , 18 ° 51 ′ 0 ″ E ). The paralectotype was found in a place called Quibis, according to the collection label. This is the town of Kuibis on the Huib plateau in the constituency ǃNamiǂNûs , until 2013 constituency Lüderitz, about 200 kilometers from the Karas Mountains ( 26 ° 41 ′ 0 ″ S , 16 ° 50 ′ 0 ″ E ). In the past, the possibility was considered that it could be a place in the area of the Karas Mountains that no longer exists under this name today. However, this does not correspond to the documented itinerary of the expedition by John Hewitt and Paul A. Methuen in 1913, on which the first specimens were found.
The species is endemic to southern Namibia and north-western South Africa. The localities in Namibia are exclusively in the regions Hardap and ǁKaras, the South African localities are in the province of North Cape . Karasbergia methueni has been found at altitudes of over 1,500 meters. The distribution area is more than two thirds in the Namaqualand and a large part in the Succulent Karoo . The sandy areas of the Kalahari and the Namib seem to be natural limits of distribution.
Way of life
Karasbergia methueni is a nocturnal and pelophilic species that spends the day in its living tubes under stones. It was most commonly found in rocky habitats with hard and often rocky soil. The clear majority of male scorpions that have been collected suggests that the female animals are less likely to be outside their burrows. The mating ritual takes place on stone surfaces on which the hemispermatophore is also deposited.
The species lives sympatric with more than a dozen species of scorpions in its range . Most species prefer soil structures other than Karasbergia methueni . With Parabuthus brevimanus it occurs most often syntopically . When keeping Karasbergia methueni in a terrarium , groups of both sexes, even with scorpions of different ages, show only a slight tendency to aggression and cannibalism.
Danger
Karasbergia methueni is known from about 75 localities, which are in an area with an area of about 48,000 square kilometers. The distribution area is mostly unsuitable for agricultural use. The only exceptions are the banks of the Orange River with diamond mines and agriculture. Apart from the already low threat to the habitats, a large part of the range is in national parks. A threat to the continued existence of the company is therefore currently excluded.
Systematics
The genus Karasbergia is monotypical, with the species Karasbergia methueni . It is placed in the Buthidae family due to the number and distribution of trichobothria and the shape of the hemispermatophores, as well as some other diagnostic features . Their phylogenetic position within the Buthidae is unclear. In 1913, Hewitt pointed to a close relationship to the genus Uroplectes . Later he added to his assumption by pointing out clear differences between the two genera and referred to Karasbergia as the most original genus of the Buthidae family. In 1979, in his monograph on the scorpions of Namibia, Lamoral saw himself unable to assign Karasbergia a certain position within the Buthidae.
In 2003, the US arachnologists Michael E. Soleglad and Victor Fet published a comprehensive reorganization of the higher systematics of the scorpions. The genus Karasbergia was placed by them as a sister taxon next to an extensive clade with the New World genera Centruroides , Microtityus and Tityus as well as the Old World genera Grosphus , Microcharmus and Uroplectes . Soleglad's and Fet's work was generally rejected in an unusually sharp manner by Prendini and colleagues. With regard to the position of Karasbergia , Prendini pointed out that Soleglad and Fet, along with numerous other shortcomings in their work, had to be reproached , that important taxa such as the genus Chaerilus and essential diagnostic features of the Buthids had not been considered in their cladistic analysis.
Initial description
The first description of Karasbergia methueni was made in 1913 by the British zoologist John Hewitt after three female specimens of the type locality. It was not until 1979 that the South African Bruno H. Lamoral described the male scorpions. In 2004, the US arachnologist Lorenzo Prendini published a revision of the genus Karasbergia with a new description of the species.
Type material
The type species of the genus Karasbergia is, due to its monotype , Karasbergia methueni . At the time it was first described, the type material of the species consisted of a series of three syntypes . Of these, only two could be found by Lamoral in 1979, which he determined as the lectotype and the paralectotype. The third syntype is considered lost. The type specimens are in the collection of the Ditsong National Museum of Natural History in Pretoria.
etymology
The generic name Karasbergia refers to the terra typica of the only species, the Karasberg in southeastern Namibia. The species name methueni honors the British zoologist Paul Ayshford Methuen .
literature
- John Hewitt: The Percy Sladen Memorial Expedition to Great Namaqualand 1912-13. Records and descriptions of the Arachnida of the collection. Order Scorpiones . In: Annals of the Transvaal Museum 1913, Volume 4, No. 3, pp. 146–159, Plate XV, digitized .
- Bruno H. Lamoral: The scorpions of Namibia (Arachnida: Scorpionida) . In: Annals of the Natal Museum 1979, Volume 23, No. 3, pp. 497-784, here pp. 555-560, ISSN 0304-0798 , online .
- Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa . In: Journal of Afrotropical Zoology 2004, Volume 1, pp. 77-93, ISSN 1781-1104 .
Individual evidence
- ↑ a b c d Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 79.
- ↑ a b c Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 84.
- ↑ a b c d Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 88.
- ↑ a b c d Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 89.
- ↑ a b c d Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 80.
- ^ Paul A. Methuen: The Percy Sladen Memorial Expedition to Great Namaqualand 1912-13. Zoology. Introduction . In: Annals of the Transvaal Museum 1913, Volume 4, No. 3, pp. 113–115, digitized .
- ^ A b Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 90.
- ↑ Michael E. Soleglad and Victor Fet: High-level systematics and phylogeny of the extant scorpions (Scorpiones: Orthosterni). In: Euscorpius 2003, No. 11, p. 1 Online PDF , 37.5 MB.
- ↑ Lorenzo Prendini and Ward C. Wheeler: Scorpion higher phylogeny and classification, taxonomic anarchy, and standards for peer review in online publishing. In: Cladistics 2005, Volume 21, No. 5, pp. 446-494, Online PDF , 1.8 MB.
- ↑ Lorenzo Prendini: Revision of Karasbergia Hewitt (Scorpiones: Buthidae), a monotypic genus endemic to southern Africa , p. 77.
- ^ John Hewitt: The Percy Sladen Memorial Expedition to Great Namaqualand 1912-13. Order Scorpiones .
- ↑ a b Bruno H. Lamoral: The scorpions of Namibia (Arachnida: Scorpionida) , p. 555.
- ↑ Gérard Dupré: Dictionary of scientific scorpion names. In: Arachnides. Bulletin de Terrariophilie et de Recherche 2016, Supplément au n ° 78, pp. 32 and 40, online PDF , 560 kB.
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