29 December, 2010

Life cycle data for Opisthacanthus madagascariensis

Wilson Lourenco and co-workers have recently published a paper with life history data for Opisthacanthus madagascariensis (Hemiscorpiidae) from Madagascar.

Biological observations were made during the 1980s by the senior author on living specimens of Opisthacanthus madagascariensis Kraepelin, 1894. These were collected by French biologists on a field trip in 1980-1981 to the Parc National de Namoroka, Mahajanga Province, Madagascar. The total duration of embryonic development averaged 18 months. The moults necessary to reach the various juvenile instars and adulthood took place at average ages of 13, 101, 204, 327 and 442 days. These developmental periods are significantly longer than those of most medium-sized species of scorpions but are similar to the ones previously observed in other species of the genus Opisthacanthus. Morphometric growth values of the different instars are also similar to those in other known species of Opisthacanthus. A significant allometric growing of pedipalps is observed for some males collected in the field, suggesting the existence of at least one extra instar.

Lourenco WR, Leguin E-A, Cloudsley Thompson JL. The life cycle of the Malagasy scorpion Opisthacanthus madagascariensis Kraepelin, 1894 (Liochelidae). Entomol Mitt Zool Mus Hamburg. 2010;15(183):173-82.

Family Hemiscorpiidae

23 December, 2010

Seasons Greeting

I wish you all a Merry Christmas and a Peaceful New Year!

Jan Ove Rein
Editor of The Scorpion Files

New Heterometrus from India

Javed and co-workers has recently described a new Heterometrus (Scorpionidae) from India:

Heterometrus telanganaensis Javed, Mirza, Tampal & Lourenco, 2010

The papers also has some information about the new species' natural history.

A distinctive new species of the genus Heterometrus Ehrenberg, 1828 is described from the Indian state of Andhra Pradesh. Heterometrus telanganaensis sp. nov. differs from all Indian species of the genus in being one of the smallest species with a relatively short metasoma.

Maqsood Javed SM, Mirza ZA, Tampal F, Lourenco WR. A new species of the genus Heterometrus Ehrenberg, 1828 (Scorpiones: Scorpionidae) from India with notes on its natural history. Boletin de la SEA. 2010(47):143-8.

Thanks to Javed for sending me the paper and sharing the picture with The Scorpion Files!

Family Scorpionidae

21 December, 2010

Biochemical analysis of Hemiscorpius lepturus venom

Hemiscorpius lepturus Peters, 1861 (Hemiscorpiidae) is a highly cytotoxic scorpions that has the highest mortality rate among scorpions in Iran. Causing different symptoms than most other scorpions, knowledge about the biochemistry and toxicology of the Hemiscorpius venom is important.

Ramin Seyedian and co-workers have now published an enzymatic analysis of Hemiscorpius lepturus venom that increase the knowledge of the venom composition and how the venom works on the human body. This knowledge is important in the development of better treatment of the sting victims of this dangerous species.

Hemiscorpius lepturus envenomation exhibits various pathological changes in the affected tissues, including skin, blood cells, cardiovascular and central nervous systems. The enzymatic activity and protein component of the venom have not been described previously. In the present study, the electrophoretic profile of H. lepturus venom was determined by SDS-PAGE (12 and 15%), resulting in major protein bands at 3.5–5, 30–35 and 50–60 kDa. The enzymatic activities of the venomwas, for the first time, investigated using various zymography techniques, which showed the gelatinolytic, caseinolytic, and hyaluronidase activities mainly at around 50–60 kDa, 30–40 kDa, and 40–50 kDa, respectively. Among these, the proteolytic activities was almost completely disappeared in the presence of a matrix metalloproteinase inhibitor, 1, 10-phenanthroline. Antigen-antibody interactions between the venom and its Iranian antivenin was observed by Western blotting, and it showed several antigenic proteins in the range of 30–160 kDa. This strong antigen– antibody reaction was also demonstrated through an enzyme-linked immunosorbent assay (ELISA). The gelatinase activity of the venom was suppressed by Razi institute polyvalent antivenin, suggesting the inhibitory effect of the antivenin against H. lepturus venom protease activities. Prudently, more extensive clinical studies are necessary for validation of its use in envenomed patients.

Seyedian R, Pipelzadeh MH, Jalali A, Kim E, Lee H, Kang C, et al. Enzymatic analysis of Hemiscorpius lepturus scorpion venom using zymography and venom-specific antivenin. Toxicon. 2010 Sep 15;56(4):521-5. [Subscription required for fulltext]

Thanks to Ramin Seyedian for sending me this paper!

17 December, 2010

Water loss in scorpions

Scorpions are known for low metabolic rates and low water loss rates. Previously, we have learned that mesic and/or burrowing species have had lower water loss rates than xeric species due to a life in a "better" microclimate. A new study shows that it ain't necessarily so.

Eran Gefen have now published a very interesting study investigating how the relative importance of respiratory water loss is correlated with species habitat type and activity pattern, using both xeric and mesic and burrowing and non-burrowing species. Also, Gefen's study has an improved experimental design placing the scorpions in a more realistic situation during experiments and thereby getting more realistic data for water loss and metabolic rates.

A summery of the results and conclusions can be seen in the abstract below.

Scorpions exhibit some of the lowest recorded water loss rates compared with those of other terrestrial arthropods of similar body size. Evaporative water loss (EWL) includes cuticular transpiration and respiratory water loss (RWL) from gas exchange surfaces, that is, book lung lamellae. Estimated fractions of cuticular and respiratory losses currently available from the literature show considerable variation, at least partly as a result of differences in methodology. This study reports RWL rates and their relative importance in scorpions from two families (Buthidae and Scorpionidae), including both xeric and mesic species (or subspecies). Two of the included Buthidae were surface-dwelling species, and another inhabits empty burrows of other terrestrial arthropods. This experimental design enabled correlating RWL importance with scorpion phylogeny, habitat type, and/or homing behavior. Buthidae species exhibited significantly lower EWL rates compared with those of Scorpionidae, whereas effects of habitat type and homing behavior were not significant. Resting RWL rates were not significantly affected by scorpion phylogeny, but rates for the xeric species (totaling ∼10% of EWL rates at 30 C) were significantly lower compared with those of mesic species. These lower RWL values
were correlated with significantly lowerH2O/CO2 emission rates in xeric species. The experimental setup and ∼24-h duration of each individual recording allowed estimating the effect of interspecific variation in activity on RWL proportions. The high respiratory losses in active hydrated Scorpio maurus fuscus, totaling 30% of EWL, suggest that behavioral discretion in this species is a more likely mechanism for body water conservation under stressful conditions when compared with the responses of other studied species.

Gefen E. The Relative Importance of Respiratory Water Loss in Scorpions Is Correlated with Species Habitat Type and Activity Pattern. Physiol Biochem Zool. 2010 Nov 19. [Published ahead of print] [Subscription required for fulltext]

Thanks to Dr. Gefen for sending me this paper!

16 December, 2010

A new Butheoloides from Morocco

Wilson Lourenco has described a new species of Butheoloides Hirst, 1925 (Buthidae) from Morocco, bringing the number of species in the genus up to 13:

Butheoloides slimanii Lourenco, 2010

The paper also record Butheoloides monodi Vachon, 1950 from Guinea Bissau for the first time.

A new species belonging to the genus Butheoloides Hirst, 1925 (subgenus Butheoloides Hirst, 1925) (Scorpiones, Buthidae) is described from the northern range of the Atlas Mountains in Morocco. With the description of Butheoloides (Butheoloides) slimanii sp. n., the total number of species known from Morocco is
raised to four. Butheoloides (Butheoloides) monodi Vachon, 1950 is also recorded from Guinea Bissau for the first time.

Lourenco WR. A new species of Butheoloides Hirst, 1925 from Morocco (Scorpiones, Buthidae). Entomol Mitt Zool Mus Hamburg. 2010;15(183):183-9.

Thanks to Gerard Dupre for sending me this paper!

Family Buthidae

A remarkable new genus and species of Pseudochactidae from Vietnam

New scorpion taxa are discovered regularly, but sometimes really fantastic discoveries are made. This is one of them! Lourenco & Pham have recently described a remarkable new troglobitic genus and species from the Tien Son Cave in Vietnam. The new taxa belongs to the enigmatic family Pseudochactidae Gromov, 1998, which now has three genera with three species from Tajikistan, Uzbekistan, Laos and Vietnam. There is not a consensus within the scorpion community on the phylogenetic position of this family, but there is an agreement that this family has a basal status among recent scorpions.

Vietbocap Lourenco & Pham, 2010
Vietbocap canhi Lourenco & Pham, 2010

This is the first true troglobite (loss of eyes and pigmentation and living in caves) reported for this family.

A new genus and species of scorpion belonging to the family Pseudochactidae are described based on four specimens collected in the Tien Son cave at the Phong Nha - Ke Bang National Park, Quang Binh Province, Vietnam. The new species represents a true troglobitic element, the first one known for the family Pseudochactidae. This represents the third known record of a pseudochactid, and the first from Vietnam.

Lourenco WR, Pham D-S. A remarkable new cave scorpion of the family Pseudochactidae Gromov (Chelicerata, Scorpiones) from Vietnam. ZooKeys. 2010;71:1-13. [Free fulltext, but article not available online yet]

Thanks to Gerard Dupre for sending me this paper!

Family Pseudochactidae

15 December, 2010

First record of Orthochirus from Turkey

Ersen Yagmur has recently published a paper reporting the first occurrence of the genus Orthochirus Karsch, 1891 (Buthidae) from Turkey. The species found was O. zagrosensis Kovarik, 2004, which previously has been reported only from Iran.

The above raises the number of Turkish genera and species to 11 and 23.

This study reports the first record of a genus and a species for the Turkish scorpion fauna. The scorpion Orthochirus zagrosensis Kovařík, 2004 is recorded from Hakkari Province. Body measurements and geographical distribution of the species are provided.

Yagmur EA. First record of Orthochirus Karsch, 1891 (Scorpiones, Buthidae) from Turkey. Anadolu Doga Bilimleri Dergisi. 2010;1(1):15-9. [Free fulltext]

Thanks to Ersen for sending me this paper!

14 December, 2010

Scorpion fluorescence - a way to avoid moonlight?

Scorpions fluorescence under UV-light. This is a great phenomenon for scorpion scientists and enthusiasts wanting to find and study scorpions, but its function has not been known so far. Suggested functions have been uv-light detection, mate identification, species identification, luring of prey, light amplification and that the fluorescence has no fuction at all.

Carl Kloock has written several papers on scorpion fluorescence (previous blog post), and in his latest paper (authored together with Abraham Kubli and Ricco Reynolds) it is concluded that their experimental data support the hypothesis that scorpion fluorescence serves as a means for the detection of UV-light at very low levels. Further, it is suggested that the UV-light acts as a cue for moonlight avoidance (fluorescence is a way to detect the presence of uv-light which is correlated to a moonlit night and this cause the scorpions to stay hidden in their hidings).

This is the first experimental evidence for a potential function for scorpion fluorescence, but further studies are necessary before final conclusion can be made on this phenomenon.

The hypothesis that fluorescence in scorpions functions in the detection of ultraviolet light was tested. We reduced the fluorescence of scorpions by prolonged exposure to ultraviolet light on a 16:8 h light:dark cycle and compared their activity levels and light environment choices to unmodified scorpions in simple arenas that were half in shadow and half exposed to light. Three different lighting conditions were tested: infrared (IR) light only, IR + ultraviolet light and IR + white light. Treatments were illuminated by infrared light for videotaping. Activity level was measured by the number of transitions from the exposed to shadowed regions, and choice was measured by the percentage of time spent in the shadowed portion of the arena. Under IR + ultraviolet light, fluorescent scorpions reduced their activity levels and the variance in habitat choice increased, compared with reduced-fluorescence scorpions. There were no differences between fluorescent and non-fluorescent scorpions in the IR only condition or in the IR + white light condition. This is interpreted as evidence that fluorescence aids in the detection of and response to ultraviolet light, and possible implications of this result in natural habitats are discussed. This is the first experimental demonstration of a possible function for scorpion fluorescence.

Kloock CT, Kubli A, Reynolds R. Ultraviolet light detection: A function of scorpion fluorescence. Journal of Arachnology. 2010;38(3):441-5. [Subscription required for fulltext, but free fulltext after 12 months]

13 December, 2010

Scorpion stings in children in Tunisia

As mentioned in a previous posting, children are more vulnerable to scorpion stings than adults. Bahloul and co-workers have now published an extensive study of scorpion envenomation among 685 children in Tunisia.

The most dangerous species in the study area were Androctonus australis and "Buthus occitanus" [The former Buthus occitanus and subspecies in North Africa has been split into new several new species and it is not possible for me to say which species that may be the one(s) involved in serious envenomations in Tunisa].

Our objective was to characterize both epidemiologically and clinically manifestations after severe scorpion envenomation and to define simple factors indicative of poor prognosis in children. We performed a retrospective study over 13 years (1990–2002) in the medical intensive care unit (ICU) of a university hospital (Sfax-Tunisia). The diagnosis of scorpion envenomation was based on a history of scorpion sting. The medical records of 685 children aged less than 16 years who were admitted for a scorpion sting were analyzed. There were 558 patients (81.5%) in the grade III group (with cardiogenic shock and/or pulmonary edema or severe neurological manifestation [coma and/or convulsion]) and 127 patients (18.5%) in the grade II group (with systemic manifestations). In this study, 434 patients (63.4%) had a pulmonary edema, and 80 patients had a cardiogenic shock; neurological manifestations were observed in 580 patients (84.7%), 555 patients (81%) developed systemic inflammatory response syndrome (SIRS), and 552 patients (80.6%) developed multi-organ failure. By the end of the stay in the ICU, evolution was marked by the death in 61 patients (8.9%). A multivariate analysis found the following factors to be correlated with a poor outcome: coma with Glasgow coma score ≤ 8/15 (odds ratio [OR] = 1.3), pulmonary edema (OR = 2.3), and cardiogenic shock (OR = 1.7). In addition, a significant association was found between the development of SIRS and heart failure. Moreover, a temperature > 39°C was associated with the presence of pulmonary edema, with a sensitivity at 20.6%, a specificity at 94.4%, and a positive predictive value at 91.7%. Finally, blood sugar levels above 15 mmol/L were significantly associated with a heart failure. In children admitted for severe scorpion envenomation, coma with Glasgow coma score ≤ edema, and cardiogenic shock were associated with a poor outcome. The presence of SIRS, a temperature > 39°C, and blood sugar levels above 15 mmol/L were associated with heart failure. 8/15, pulmonary

Bahloul M, Chabchoub I, Chaari A, Chtara K, Kallel H, Dammak H, et al. Scorpion envenomation among children: clinical manifestations and outcome (analysis of 685 cases). Am J Trop Med Hyg. 2010 Nov;83(5):1084-92. [Subscription required for fulltext]

10 December, 2010

Mesobuthus eupeus - a species complex?

Mesobuthus eupeus (C. L. Koch, 1839) is the most widely dispersed species in the genus Mesobuthus and even one of the most widespread species within the family Buthidae. It has been reported from eastern and central parts of Turkey, Armenia, Azerbaijan, Georgia, southern Russia, Syria, Iraq, Iran, Afghanistan, Pakistan, Central Asia, southern Mongolia and northern China. Several subspecies have been described with varying degrees of morphological variations.

Omid Mirshamsi and co-workers have now published a paper on the phylogenetic relationships of Mesobuthus eupeus based on genetic analysis of 59 specimens. The resulting data indicate two distinct lineages within the species, suggesting that it may be a species complex consiting of at least two species. More studies are necessary though, before any taxonomic decisions can be made.

In this study, the first molecular phylogenetic analysis of Mesobuthus eupeus in Iran is presented based on sequence data of a ∼ 700-base-pair fragment of cytochrome C oxidase, subunit I. Phylogenetic relationships were inferred using parsimony, maximum likelihood and Bayesian inference. The results support monophyly of M. eupeus, but there is a clear divergence between northern and southern clades. The northern clade includes four subspecies – M. e. eupeus, M. e. philippovitschi, M. e. afghanus and M. e. thersites; whereas the southern clade is comprised of two others – M. e. phillipsi and M. e. kirmanensis. Accordingly, possible scenarios for the evolution and phylogeographic structure of M. eupeus based on the geological history of the Iranian Plateau were proposed. The observation of two distinct lineages supports the proposal that M. eupeus might be a species complex composed of species with highly similar morphological features.

Mirshamsi O, Sari A, Elahi E, Hosseinie S. Phylogenetic relationships of Mesobuthus eupeus (C.L. Koch, 1839) inferred from COI sequences (Scorpiones: Buthidae). Journal of Natural History. 2010;44(47):2851-72.

Thanks to Dr. Mirshamsi for sending me this paper!

Family Buthidae

Description of the female of Oiclus nanus

Teruel & Chazal described very recently Oiclus nanus Teruel & Chazal, 2010 (Scorpionidae) from Guadeloupe, Lesser Antilles. In the current paper, the adult female is described for the first time.

The adult female of Oiclus nanus Teruel et Chazal, 2010 is herein described for the first time, on the basis of a topotypic specimen. Taxonomic diagnosis of this species endemic from Guadeloupe is emended, and the comparison to its closest relative is also improved.

Teruel R, Chazal L. On the adult female of Oiclus nanus Teruel et Chazal, 2010 (Scorpiones: Scorpionidae: Diplocentrinae). Euscorpius. 2010(106):1-6. [Free fulltext]

Family Scorpionidae

09 December, 2010

Three cases of Euscorpius sting in Italy

I always tell peoples that contact me after finding Euscorpius in their homes and holliday houses in France, Italy and Greece that no species in this genus are harmless. This info is based on own experiences and the general opinion among scorpion experts, but there is very little in the literature adressing the consequences of stings from this genus.

M. Dutto and co-workers have now published three case reports of Euscorpius sting from northwestern Italy. Fortunately, this study confirms the general notion that Euscorpius mainly causes local effects like pain, skin discoloration and swelling, and that symptoms rapidly dissipate. Other symptoms may have a psychological etiology because of patient's fear and agitation from the sting.

One important caution from the authors however, is that patients where the involved scorpion has not been identified should be observed for a time. Non-native scorpions to Italy/Europe (either introduced as stowaways or kept as pets) may have been involved, and these may cause more serious symptoms.

In the period between June 2008 and August 2009, three cases of stings of Euscorpius scorpions indigenous to Italy were treated at two different emergency departments (ED) in hospitals of the Piedmont region, northwest Italy: Santa Croce e Carle General Hospital in Cuneo, and Santissima Annunziata Hospital in Savigliano. Scorpion stings in Italy are rare and not well documented in the literature; this situation may raise doubts among medical personnel as to how such lesions are best treated. Analysis of the incidents confirms that the venom of Euscorpius do not provokes systemic poisoning in humans and in these cases even dermatological reactions were not significant.

Dutto M, Dutto L, Scaglione N, Bertero M. Euscorpius (Scorpiones, Euscorpiidae): three cases of stings in northwestern Italy. Journal of Venomous Animals and Toxins Including Tropical Diseases. 2010;16(4):659-63. [Free fulltext]

02 December, 2010

Scorpion eating bats

Even though scorpions are notorious predators with a venomous sting, they also are prey for other predators including several vertebrate predators like reptiles, birds and mammals. Marc Holderied and co-workers have published an interesting study showing how the Hemprich's long-eared bat (Otonycteris hemprichii) prey on scorpions in Israel.

Interestingly, the bats didn't differ between potent species like Leiurus quinquestriatus and more harmless species like Scorpio maurus, and stings didn't change the bat's behavior and caused no sign of poisoning.

Over 70% of the droppings of the gleaning bat Otonycteris hemprichii can contain scorpion fragments. Yet, some scorpions found in its desert habitat possess venom of the highest known toxicity, rendering them a very dangerous prey. In this study, we describe how O. hemprichii catches and handles scorpions, quantify its flight and echolocation behaviour in the field, investigate what sensory modality it uses to detect scorpions, and test whether it selects scorpions according to their size or toxicity. We confirmed that O. hemprichi is a whispering bat (approx. 80 dB peSPL) with short, multi-harmonic calls. In a flight room we also confirmed that O. hemprichii detects scorpions by their walking noises. Amplitudes of such noises were measured and they reach the flying bat at or below the level of echoes of the loess substrate. Bats dropped straight onto moving scorpions and were stung frequently even straight in their face. Stings did not change the bats’ behaviour and caused no signs of poisoning. Scorpions were eaten including poison gland and stinger. Bats showed no preference neither for any of the scorpion species nor their size suggesting they are generalist predators with regard to scorpions.

Holderied M, Korine C, Moritz T. Hemprich's long-eared bat (Otonycteris hemprichii) as a predator of scorpions: whispering echolocation, passive gleaning and prey selection. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2010. Ahead of Print Nov 18. DOI: 10.1007/s00359-010-0608-3. [Subscription required for fulltext]