A comparative cytogenetic study of a three Hadogenes species results in a new species from South Africa

Frantisek Stahlavsky and co-workers have recently published the first comparative cytogenetic study in Hadogenes species (Hormuridae) using both standard and molecular cytogenetic approaches. A new species from South Africa is also described.

Hadogenes weygoldti Stahlavsky, Stundlova, Lowe, Stockmann & Kovarik, 2018

Abstract:
In the present study, we performed the first comparative cytogenetic study in Hadogenes species using both standard and molecular cytogenetic approaches. Information about the diploid set, number and distribution of 18S rDNA and telomeric sequences was obtained from three South African species, Hadogenes trichiurus (Gervais, 1843), H. zuluanus Lawrence, 1937 and H. weygoldti sp. n. All species analysed differ considerably in the number of chromosomes (H. trichiurus 2n=48, H. zuluanus 2n=80, H. weygoldti sp. n. 2n=113). In contrast, the number of 18S rDNA clusters and distribution of telomeric sequences represent rather stable cytogenetic characters in Hadogenes. Within all karyotypes, we identified one pair of 18S rDNA clusters. The telomeric signals were exclusively on the terminal chromosomal regions. Interestingly, the chromosomal location of 18S rDNA clusters varied from terminal to interstitial in species karyotypes, indicating the presence of hidden structural chromosomal changes. Additionally, the present comparative study is complemented by the description of a new species, H. weygoldti sp. n., based on specific karyotype features and morphological characters. Finally, our cytogenetic results are compared with known chromosomal data of other Hadogenes species, and the use of cytogenetic approaches in the taxonomy of scorpions is discussed.

Reference:
Šťáhlavský F, Štundlová J, Lowe G, Stockmann M, Kovařík F. Application of cytogenetic markers in the taxonomy of flat rock scorpions (Scorpiones: Hormuridae), with the description of Hadogenes weygoldti sp. n. Zoologischer Anzeiger. 2018;Accepted Manuscript. [Subscritpion required for full text]

Family Hormuridae

A survey of the Brandberg Massif, Namibia

Namibia has the most diverse scorpion fauna in southern Africa, and all four African families are represented here (Bothriuridae, Buthidae, Hemiscorpiidae, Scorpionidae). Lorenzo & Bird has now published a survey of the scorpion fauna of the Brandberg Massif in Namibia.

The article has ecolocial notes on most species and color pictures of many species and their habitats. See abstract and article for further details.

Abstract:
A previous list of scorpions from the Brandberg Massif and vicinity, north-western Namibia (Omaruru District, Erongo Region), is updated, based on a survey of the Massif and surrounding areas (the region delimited by 21 degrees 00'S-21 degrees 30'S and 14 degrees 00'E-15 degrees 00'E) conducted during three separate expeditions, and augmented by an examination of material in museum collections. More than 1000 specimens, representing more than 100 point-locality records, were examined for the study. Notes on the ecology and distribution of the scorpions on the Massif and surrounding areas are provided. Excluding one dubious record, 20 scorpion species in seven genera (Brandbergia, Lisposoma, Hottentotta, Parabuthus, Uroplectes, Hadogenes, and Opistophthalmus) of four families (Bothriuridae, Buthidae, Liochelidae, Scorpionidae) are recorded from the area, which presently has the richest scorpion fauna in Namibia, if not southern Africa, and ranks among those with the richest scorpion faunas in the world. The high diversity of scorpions on the Brandberg Massif and vicinity is attributed to the heterogeneity of landforms, substrata and habitats in the area. The scorpions of the Massif and surrounding areas may be classified into seven ecomorphotypes, using every available niche. The species richness of the scorpion fauna is inversely correlated with altitude. The greatest diversity of genera and species occurs at the base of the Massif and in the surrounding areas, and decreases towards the summit. Five species occur in the area surrounding the Massif but not at its base, five at its base (below 500 m) but not on its slopes, two on its lower slopes (500-1000 m), but not on its middle slope (1000-1500 m), upperslope (1500-2000 m) or summit (above 2000 m), and two on its summit, upper and middle slopes only. Only five species occur from the base to the summit of the Massif.

Reference:
Prendini L, Bird TL. Scorpions of the Brandberg Massif, Namibia: Species richness inversely correlated with altitude. Afr Invertebr. 2008 Dec;49(2):77-107 [Free fulltext (not yet available)]