30 June, 2011

A new Centruroides from Mexico

Ponce-Saavedra and Francke recently published a new Centruroides (Buthidae) from Mexico.

Centruroides macota Ponce-Saavedra & Francke, 2011

Ponce-Saavedra J, Francke OF. Nueva especie de alacran del genero Centruroides (Scorpiones, Buthidae) del estado de Jalisco, Mexico. Revista Mexicana de Biodiversidad. 2011;82:465-74.8Free fultext]

Thanks to Oscar Francke for sending med this paper!

Family Buthidae

14 June, 2011

How do the scorpion pectines work?

Elisabeth Knowlton and Douglas Gaffin have recently published a paper looking into how the thousands of peg sensilla that cover the pectines work.

All scorpions have two mid-ventral organs called pectines. Each pecten has thousands of pore-tipped sensilla sensitive to a variety of volatile organic and waterbased stimulants. However, it was previously unknown whether individual sensilla were functionally identical or different. The information enhancement hypothesis predicts that all sensilla have similar chemosensitivities such that each is a unit of a parallel processing system. The information segmentation hypothesis states that sensilla differ in their chemosensitivities, a functional arrangement akin to the glomeruli-specific chemical detection system in the moth or human olfactory sense. In this study, we tested these hypotheses by extracellularly tip-recording sensillar responses to three aqueous tastants: 0.01 M KCl, 0.1 M citric acid, and 40% ethanol by volume. We isolated stimulation to one sensillum at a time and compared the chemoresponses. Sensilla appeared to respond similarly to the same stimulant (i.e., sensillar tip-recordings revealed activity of the same cell types), although sometimes a few sensilla responded with higher spike rates than the others. We conclude that our data primarily support the information enhancement hypothesis but for future tests of sensillar function we suggest a new hybrid model, which proposes that a few specialized sensilla exist among a mostly uniform field of identical sensilla.

Knowlton ED, Gaffin DD. Functionally redundant peg sensilla on the scorpion pecten. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2011 Jun 7.doi: 10.1007/s00359-011-0650-9. [Subscription required for fulltext]

08 June, 2011

A review of scorpion reproductive strategies

Michael Warburg has recently published an interesting review on scorpion reproductive strategies. In addition to reviewing the existing knowledge on this topic, he also makes suggestions about future research on this topic.

Most scorpion species are iteroparous, breeding more than once during their life. Some of these species are parthenogenetic. The other reproductive strategy (RS) semelparity, when scorpions breed only a single time during their life, is rare and has been documented only once. The mass allocated by the female to produce either a litter or a single offspring is the reproductive allocation (RA). It is difficult to calculate RA since the difference in female mass before and after parturition is difficult to obtain. In addition, the litter size is hardly ever accurate because of maternal cannibalism. An attempt was made to calculate RA in Nebo hierichonticus (E. Simon, 1872). Based on litter size, on breeding frequency and on longevity of the female, it is possible to estimate the reproductive potential (RP). These aspects of scorpion reproduction are reviewed and the difficulties involved in this study are discussed.

Warburg MR. Scorpion reproductive strategies, allocation and potential; A partial review. European Journal of Entomology. 2011;108(2):173-81. [Free fulltext]

07 June, 2011

A redescription of Tityus atriventer

Rolando Teruel and Frantisek Kovarik have published an article with a redescription of Tityus atriventer Pocock, 1897 (Buthidae) from the Caribbean.

The largely neglected Lesser Antillean scorpion Tityus atriventer Pocock, 1897 is herein redescribed, after study of the two syntypes and one additional adult male. The latter was recently collected from Union Island (about 55 km northeast of Grenada), and it implies the first published finding of this species after its original description, and the first record of the species both outside the type-locality and from the Grenadines islands. The taxonomic position of T. atriventer is clarified (including designation of a lectotype and a paralectotype), its diagnosis is updated, a fully illustrated redescription is presented according to the current taxonomy of the genus, and a comparison to its morphologically closest relatives is also provided.

Teruel R, Kovarik F. Redescription and taxonomic position of Tityus atriventer Pocock, 1897 (Scorpiones: Buthidae). Euscorpius. 2011(115):1-9. [Free fultext]

Family Buthidae

03 June, 2011

A review of Colombian Ananteris with two new species

Ricardo Botero-Trujillo and Eduardo Florez D have published a review on the Colombian Ananteris (Buthidae). Two new species are described:

Ananteris ochoai Botero-Trujillo & Florez D, 2011
Ananteris solimariae Botero-Trujillo & Florez D, 2011

In addition, Ananteris hasshy Teruel & Roncallo, 2008 is synonymized with A. columbiana, 1991. See abstract for further details.

Some contributions to the knowledge of the buthid scorpion genus Ananteris Thorell, 1891 in Colombia are herein presented, based upon the examination of over 100 specimens. Ananteris ochoai sp. nov. and Ananteris solimariae sp. nov. are described from Nariño and Santander departments, respectively. The recently described Ananteris hasshy Teruel & Roncallo, 2008 is synonymized under Ananteris columbiana Lourenço, 1991 based on several evidences from morphology. The males of Ananteris dorae Botero-Trujillo, 2008, Ananteris ehrlichi Lourenço, 1994 and Ananteris myriamae Botero- Trujillo, 2007, and the female of Ananteris arcadioi Botero-Trujillo, 2008 are described for the first time. Ananteris meridana González Sponga, 2006 is reported for the first time for Colombia and the genus Ananteris for the departments of Cundinamarca, Santander and Norte de Santander. Likewise, new locality records are given for A. arcadioi, A. dorae and A. myriamae. Revised diagnoses and data on intraspecific variability are provided for A. arcadioi, A. columbiana, A. dorae, A. ehrlichi, A. meridana and A. myriamae. Hemispermatophore morphology is described for the first time for A. arcadioi, A. columbiana, A. dorae, A. ehrlichi, A. meridana, A. myriamae, A. ochoai sp. nov. and A. solimariae sp. nov., providing evidence of this structure’s taxonomic usefulness and revealing a paramount need to describe it in further taxonomic works on Ananteris. Some notes on the use of the fixed finger trichobothria for the definition of Ananteris species are provided. A distribution map plotting the known locality records of the thirteen Colombian species of Ananteris and a key to their identification are also included. Finally, the name ‘Ananteris antioquensis’, used by Otero et al. (2004) but never published, is herein deemed a nomen nudum

Botero-Trujillo R, Florez D E. A revisionary approach of Colombian Ananteris (Scorpiones, Buthidae): two new species, a new synonymy, and notes on the value of trichobothria and hemispermatophore for the taxonomy of the group. Zootaxa. 2011(2904):1-44. [Subscription required for fulltext].

Thanks to Ricardo Botero-Trujillo for sending me this paper!

Family Buthidae