24 September, 2014

Updated info on the males of three species of Tityus

The description of males in population of scorpions is an important contribution, not only as regards taxonomic knowledge of the species, but also to enable understanding of its reproductive strategy. In a recent paper, Maria Dulcineia Sales dos Santos and co-workers describe the male of T. kuryi Lourenco, 1997 for the first time and report new records of T. serrulatus and T. stigmurus males, widening the known distribution of their sexual populations. The latter two species also have several populations in Brazil that are parthenogenetic.

The male of Tityus kuryi Lourenço, 1997 is described for the first time. Despite being very similar to the female, the male presents more robust metasomal segments. Additionally, the distribution of the sexual populations of another two species of the T. stigmurus complex is reported herein: T. serrulatus Lutz & Mello, 1922 and T. stigmurus (Thorell, 1877). Males of T. serrulatus were, until now, restricted to the Minas Gerais State (Southwestern region of Brazil), and with new records reported here, its known distribution now encompasses the Northeastern region of Brazil. Males of T. stigmurus were previously recorded only for two municipalities in the State of Bahia, and here we present eight new records for Bahia State and one for Pernambuco State. We present a key to related species of the T. stigmurus complex based on morphology and coloration pattern.

Dos Santos MD, Porto TJ, Lira-da-Silva RM, Brazil TK. Description of the male of Tityus kuryi Lourenco, 1997 and notes about males of Tityus stigmurus (Thorell, 1877) and Tityus serrulatus Lutz & Mello, 1922 (Scorpiones, Buthidae). Zookeys. 2014 (435):49-61. [Free full text]

23 September, 2014

A new species of Euscorpiops from a cave system in Vietnam

Wilson Lourenco and Dinh-Sac Pham have recently published an article describing a new species of Euscorpiops Vachon, 1980 (Euscorpiidae) from the Dakrong Nature Reserve cave system in Vietnam. This new scorpion taxon is the second species of the subfamily Scorpiopinae to be discovered in a cave system and may be yet another endemic element in the fauna of this country. The new species shows some cave adaptions, but are not a true troglobitic scorpion.

Euscorpiops dakrong Lourenco & Pham, 2014

Euscorpiops dakrong sp. n., belonging to the family Euscorpiidae Laurie, is described on the basis of one male and one female collected in the Dakrong Nature Reserve cave system, Dakrong District, Quang Tri Province, Vietnam. The new species presents most features exhibited by scorpions of the genus Euscorpiops, but it is characterized by a slender body and elongated pedipalps. This new scorpion taxon represents the second species of Scorpiopinae discovered in a cave system and may be yet another endemic element in the fauna of Vietnam. Some taxonomic propositions on the generic position of Scorpiops oligotrichus Fage, 1933 are also suggested.

Lourenco WR, Pham D-S. A second species of Euscorpiops Vachon from caves in Vietnam (Scorpiones, Euscorpiidae, Scorpiopinae). Comptes Rendus Biologie. 2014;337:535-44. [Subscription required for full text]

Thanks to professor Lourenco for sending me his paper!

Family Euscorpiidae

15 September, 2014

Hormuridae Newsflash III: A new species of Hormiops

Male and female of the new species Hormiops infulcra Monod, 2014. Photo: Lionel Monod/Comptes Rendus Biologies (C)
Lionel Monod has previously published two major papers dealing with the systematics of the family Hormuridae Laurie, 1896. In a recently published third paper he presents data on the genus Hormiops Fage, 1933 in the South china Sea and a new species from two islands in Malaysia.

Important results:

Hormiops infulcra Monod, 2014: New species known only from two islands of the Seribuat Archipelagio, Malaysia.

Hormiops davidovi Fage, 1933: Distribution is now limited to (and probably also endemic to) the Con Dao Archipelagio, Vietnam.

The paper has information on Hormiops biology, habitat choice, reproduction and biogeography. An updated identification key for Australasian hormurid genera is included in the paper. 

The monotypic genus Hormiops Fage, 1933 is so far only known from two groups of granitic islands off the coasts of Peninsular Malaysia and Vietnam. Examination of newly collected material from both archipelagos and of the type series of Hormiops davidovi Fage, 1933 reveals previously disregarded morphological differences sufficient to assign the Malaysian specimens to a distinct species, described here as Hormiops infulcra sp. nov. An updated diagnosis of the genus, as well as a dichotomic key enabling the determination of Hormiops from its close relatives, Hormurus Thorell, 1876 and Liocheles Sundevall, 1833 are also provided. The phylogenetic position, distribution pattern, and ecology of these insular scorpions suggest that they are palaeoendemics, remnants of a previously more widely distributed lineage. A biogeographical model is proposed for the genus based on these observations and on a synthesis of palaeogeographical and palaeoenvironmental data currently available for Sundaland.

Monod L. The genus Hormiops Fage, 1933 (Hormuridae, Scorpiones), a palaeoendemic of the South China Sea: Systematics and biogeography. Comptes Rendus - Biologies. 2014. In Press. [Subscritpion required for full text]

Family Hormuridae

12 September, 2014

New data on the rare species Pandinus nistriae

Andrea Rossi described a new species of Pandinus Thorell, 1876 from Djobouti, Pandinus nistriae (Scorpionidae), earlier in 2014. Rossi has now published a new article with additional information about this species.

New data are presented concerning Pandinus (Pandinurus) nistriae Rossi, 2014 from Djibouti. The male holotype is directly compared with an adult male of the geographical closely related species P. magrettii Borelli, 1901 from Eritrea. It is also supposed that P. nistriae could be present in eastern Ethiopia, basing on photografic records.

Rossi A. New data on the rare species Pandinus nistriae Rossi, 2014 (Scorpiones: Scorpionidae). Arachnides. 2014 Sept;72:3-12.

Thanks to Gerard Dupre for sending me the journal Arachnides!

04 September, 2014

A new species of Chaerilus from Vietnam

Frantisek Kovarik and co-workers have recently published a new species of Chaerilus Simon, 1877 (Chaerilidae) from Vietnam.

Chaerilus hofereki Kovarik, Kral, Korinkova & Lerma, 2014

Chaerilus hofereki sp. n. from Vietnam is described and compared with C. cimrmani Kovařík, 2012 from Thailand. C. hofereki sp. n. is characterized mainly by sexual dimorphism. Chela of pedipalp is wide and ampullar, fingers shorter in male than in female. Ratio of chela length to movable finger length 2.2 in males and 1.7–2 in females. Movable finger of pedipalp with 9 or 10 cutting edges. Our study brings the first data on chromosomes of chaerilid scorpions. The karyotype of male paratype of C. hofereki sp. n. consists of high number of chromosomes (2n = 90).

Kovarik F, Kral J, Korinkova T, Lerma ACR. Chaerilus hofereki sp. n. from Vietnam (Scorpiones: Chaerilidae). Euscorpius. 2014 (189):1-11. [Free full text]

Family Chaerilidae

25 August, 2014

On the genetics of scorpion morphology

Scorpions have an unique morphology that separate them from other arthropods, especially the specialized grouping of multiple segments dedicated exclusively to prey capture and defence: the flexible metasoma (tail). Prashant Sharma and co-workers have now published an article on the genetics behind the morphology of the scorpion tail.

I embarrassingly have to admit that this article is way over my head, but I hope that readers with more knowledge into genetics will understand more than I do on this topic.

The evolutionary success of the largest animal phylum, Arthropoda, has been attributed to tagmatization, the coordinated evolution of adjacent metameres to form morphologically and functionally distinct segmental regions called tagmata. Specification of regional identity is regulated by the Hox genes, of which 10 are inferred to be present in the ancestor of arthropods. With six different posterior segmental identities divided into two tagmata, the bauplan of scorpions is the most heteronomous within Chelicerata. Expression domains of the anterior eight Hox genes are conserved in previously surveyed chelicerates, but it is unknown howHox genes regionalize the three tagmata of scorpions. Here, we show that the scorpion Centruroides sculpturatus has two paralogues of all Hox genes except Hox3, suggesting cluster and/or whole genome duplication in this arachnid order. Embryonic anterior expression domain boundaries of each of the last four pairs of Hox genes (two paralogues each of Antp, Ubx, abd-A and Abd-B) are unique and distinguish segmental groups, such as pectines, book lungs and the characteristic tail, while maintaining spatial collinearity. These distinct expression domains suggest neofunctionalization of Hox gene paralogues subsequent to duplication. Our data reconcile previous understanding of Hox gene function across arthropods with the extreme heteronomy of scorpions.

Sharma PP, Schwager EE, Extavour CG, Wheeler WC. Hox gene duplications correlate with posterior heteronomy in scorpions. Proc Biol Sci. 2014 Oct 7;281(1792). [Subscription required for full text]

Thanks to Dr. Prashant Sharma for sending me their article!

07 August, 2014

A new review on scorpion envenomation

Pathophysiological and clinical effects of systemic scorpion envenomation. Isbister & Bawaskar/New England Journal of Medicine, 2014 (C).

With more than one million cases of scorpion envenomation each year worldwide with substantial morbidity and even death in children, scorpions pose a health challenge in many countries. Geoffrey Isbister and Himmatrao Bawaskar have recently published a updated review on the effects of scorpion envenomation and the current treatment knowledge in the top medical journal New England Journal of Medicine.

This article is essential for health personnel dealing with scorpion envenomation patients, scorpion researchers and others interested in scorpions as it sums up symptoms, pathophysiology, clinical manifestations and treatment for scorpion envenomations.

Scorpion stings and envenomation are of clinical importance worldwide, and although most stings cause only local effects, severe envenomation that causes either excessive autonomic activity and cardiovascular toxic effects or neuromuscular toxic effects results in illness and, in the case of children, in death. The specific treatment is the administration of antivenom combined with symptomatic and supportive treatment, including prazosin and dobutamine in patients with cardiovascular toxic effects and benzodiazepines when there is neuromuscular involvement.

Isbister GK, Bawaskar HS. Scorpion Envenomation. N Engl J Med. 2014;371(5):457-63. [Subscription required for full text]