18 November, 2008

New Zabius species from Brazil

The Argentinean genus Zabius has previously included the common Zabius fuscus and the rare Zabius birabeni. Luis Acosta and co-workers have now disovered a new species from the State of Rio Grande do Sul in Brazil:

Zabius gaucho Acosta, Candido, Buckup & Brescovit, 2008 (Buthidae)

The article also discuss the systematics of the genus Zabius. Here is the abstract from the article (click on image to enlarge):

Acosta LE, Candido DM, Buckup EH, Brescovit AD. Description of Zabius gaucho (Scorpiones, Buthidae), a new species from southern Brazil, with an update about the generic diagnosis. Journal of Arachnology. 2008;36(3):491-501. [Subscription required for fulltext, but free fulltext after 12 months]

Family Buthidae

07 November, 2008

Two new species of Opisthacanthus from Madagascar

Madagascar is one of the most biologically diverse regions on Earth and new scorpion species are still being discovered. This time Lourenco & Goodman (2008) report about two new species in the genus Opisthacanthus from the Reserve Speciale d'Ankarana:

Opisthacanthus milloti Lourenco & Goodman, 2008
Opisthacanthus pauliani Lourenco & goodman, 2008

Interestingly, O. pauliani seems to be an obligate cave-dweller (troglobite). The article has a small discussion on troglobitism in scorpions and the scorpion fauna of the Reserve Speciale d'Ankarana. A indentification key to the Opisthacanthus of Madagascar is also included.

Lourenco WR, Goodman SM. Scorpions of the Reserve speciale d'Ankarana, Madagascar, with particular reference to cave-dwelling animals and the description of two new species (Arachnida, Scorpiones). Zoosystema. 2008;30(3):665-79. [Free fulltext]

Family Hemiscorpiidae

Morphology of spermatozoa and sperm packages in the European Belisarius xambeui

There are few modern studies on the rarest scorpion in Europe, Belisarius xambeui. This troglophylous scorpion is only reported from the southeastern Pyrenees in France and in Cataluña in Spain, and is placed in Chactidae by some authors and Troglotayosicidae by others. Vignoli, Klann & Michalik, 2008 has done a study of the morphology of the spermatozoa and sperm packages of Belisarius, and the results are linked to systematics and phylogeny. Here is the abstract from the article:

Studies on the sperm morphology in scorpions are rare, but the existing investigations already revealed a remarkable interfamiliar diversity. The present study reports for the first time on the spermatozoa and sperm packages of a representative of the family Troglotayosicidae, the troglophylous species Belisarius xambeui. The spermatozoa are characterized by (1) a thread-like nucleus, which is slightly bent anteriorly; (2) an asymmetrical cap-like acrosomal vacuole, which encloses the anterior tip of the nucleus; an acrosomal filament is absent; (3) an axoneme with a 9 + 0 microtubular pattern; (4) a midpiece consisting of elongated mitochondria coiling around the axoneme; the number can vary between 3 and 6 (mostly 4). At the end of spermiogenesis, the spermatozoa aggregate in order to form oval-shaped sperm packages in which all sperm cells show the same orientation. A single package consists of approximately 150 sperms. A secretion sheath is always absent. The present results might provide new characters for further systematic studies and their phylogenetic implications are briefly discussed.

Vignoli V, Klann AE, Michalik P. Spermatozoa and sperm packages of the European troglophylous scorpion Belisarius xambeui Simon, 1879 (Troglotayosicidae, Scorpiones). Tissue Cell. 2008;40:411-6. [Subscription required for fulltext]

Family Chactidae