Orthochirus zagrosensis, Kovařík & 1996, 2004

Kovařík, Baloorthochirus becvari & 1996, 2004, Revision and taxonomic position of genera Afghanorthochirus Lourenço & Vachon, Baloorthochirus Kova ík, Butheolus Simon, Nanobuthus Pocock, Orthochiroides Kova ík, Pakistanorthochirus Lourenço, and Asian Orthochirus Karsch, with descriptions of twelve new species (Scorpiones, Buthidae), Euscorpius 16, pp. 1-33 : 26-28

publication ID

1536-9307

publication LSID

lsid:zoobank.org:pub:4D38E32B-A445-4707-ABEE-3C6D3BFA4A2E

persistent identifier

https://treatment.plazi.org/id/038B2040-3C2B-5B37-FCB3-FB03FE91FA06

treatment provided by

Carolina

scientific name

Orthochirus zagrosensis
status

sp. n.

Orthochirus zagrosensis sp. n.

DISTINGUISHING CHARACTERS IN FORM OF KEY 1. Dorsal surface of fourth metasomal segment smooth and sharply delimited by two lateral carinae .....................……… O. iraqus sp. n. ( Iraq)

– Dorsolateral surface of fourth metasomal segment punctate or tuberculate, lateral carinae often absent, if present then do not sharply delineate border between smooth and punctate/tuberculate areas .............….. 2

2. Bristlecombs on third legs composed of 9-13 bristles...... O. afghanus sp. n. ( Afghanistan)

– Bristlecombs on third legs composed of from 4-8 bristles. ..................….. 3

3. Manus of pedipalp dark brown, mesosoma, metasoma, and femur and patella of pedipalp black…………. …………...… O. zagrosensis sp. n. ( Iran)

– Manus and patella of pedipalp yellow, mesosoma, metasoma, and femur of pedipalp greenish gray or sometimes black. … O. fuscipes (Pocock, 1900) ( Iran, India and Pakistan)

Comments on African and Arabian Species of Orthochirus

Three species are known from Africa. The first one described was Orthochirus aristidis (Simon, 1883) from Egypt, to which the same author subsequently added Orthochirus innesi Simon, 1910 , also from Egypt. Orthochirus innesi was characterized by the describer (Simon, 1910: 78–79) as having the ventral surface of the fifth metasomal segment posteriorly punctate to weakly granulose. Granules may be present also on the fourth metasomal segment, whereas in Orthochirus aristidis (Simon, 1883) the spaces among punctae are entirely smooth. However, examination of numerous specimens from populations occurring in Morocco and Egypt convinces me that the spaces among punctae may be either entirely smooth or slightly granulose, although not as much as in Asian species. The third species is Orthochirus seurati Pallary, 1929 from Algeria, which was synonymized with O. innesi by Foley (1945: 84). Unfortunately, the types of these three species are deposited at MNHN, and I was not afforded an opportunity to study them. I can only hope that MNHN will change its policy, which is detrimental to research and against the spirit of the Code ( ICZN, 1999, Recommendation 72F. 3).

In the region between Egypt and Syria there occurs a taxon which was described as Orthochirus innesi negebensis Shulov & Amitai, 1960 , and is also sometimes labeled as O. scrobiculosus negebensis (e.g. Levy & Amitai, 1980: 96; Fet & Lowe, 2000: 199). I suspect it to be a separate species, but this issue can be resolved only by study of MNHN types and their comparison with more recently collected samples of various populations.

General Discussion

The genus Orthochirus has never been revised and no acceptable key has been published. The reason may well lie in the surprising variability of characters which in other genera are considered species- and even genusdiagnostic. Searching for characters usable in a key to Orthochirus species, I have assessed the degree of variability on species available to me in reasonably large series and numbers of populations.

Buthids normally have an orthobothriotaxic pattern with 4 internal and 5 dorsal trichobothria on the femur of pedipalp; however Baloorthochirus , Orthochiroides , and Orthochirus lack trichobothrium d 2 (see Sissom 1990: 67). I at first assumed that d 2 migrated to the internal spect ( Kovarik 1996: 178) and one of the internal trichobothria was lost. It appeared to be supported by the fact that this trichobothrium is as large as d 1 and d 3 – d 5, whereas the remaining three internal trichobothria are much smaller. However, subsequent examination of Butheolus and Paraothochirus, which have d 2 situated on the dorsal surface, convinced me that it was the d 2 which was lost. The reason is that in those two genera the d 2 is smaller than the other dorsal trichobothia and on the internal surface they have one large and three small trichobothria situated exactly in place where Baloorthochirus , Orthochiroides and Orthochirus have the large internal trichobothium ( Figs. 5, 6).

One of the most important characters in scorpion taxonomy is the distribution pattern of trichobothria. For Orthochirus and its separation from related genera, the absence of trichobothrium d 2 ( Fig. 5) is an important criterion, which was used by Lourenço & Vachon (1997: 327) to establish a new genus, Paraorthochirus . However, the absence of a single trichobothrium is the only character distinguishing Paraorthochirus from Orthochirus , which makes the status of Paraorthochirus open to question. Moreover, the two genera inhabit the same region.

Tikader & Bastawade (1983: 113) used the position of trichobothrium Est on the pedipalp chela as a chief character in their key to the Indian species of Orthochirus . I checked the position of this trichobothrium in many specimens and found it to be so intraspecifically variable and population-dependent that it clearly is useless in separating species.

In a single instance, I decided to use the mutual positions of trichobothria d 1, d 3, d 4, and e 1 on the femur of pedipalp as a supplemental character. These positions, however, cannot be used as an independent character and cannot be extrapolated to the entire genus, because in the holotype of O. samrchelsis sp. n. on the left femur the distance between d 1 and d 3 is shorter than that between d 3 and d 4, and e 1 is located between d 3 and d 4 ( Fig. 5), whereas on the right femur the distance between d 1 and d 3 approximately equals that between d 3 and d 4, and e 1 is between d 4 and d 5.

As an independent character, mutual positions of any trichobothria cannot, in my opinion, be used to separate species of Orthochirus .

Another variable feature frequently encountered in the family Buthidae is the number of rows of granules on the movable fingers, existence of external and internal granules at these rows, and presence of distal granules. In Orthochirus there are 7–10 rows, most frequently 8, and they cannot be used as a principal differentiating character. The last rows are usually not slanted and often lack some accessory external and internal granules. However, all Asian species of Orthochirus have internal granules present at least at the first five rows and usually possess also external granules. Only four species ( O. feti sp. n., O. gromovi sp. n., O. heratensis sp. n., and O. scrobiculosus ( Grube, 1873)) completely lack external granules. The number of distal granules can be used as only a supplemental character and only for certain species. In the Asian species the number of distal granules varies between two and five. Two are in the Iranian O. sobotniki sp. n., O. varius sp. n., and O. zagrosensis sp. n.; all the above described new species from Afghanistan have two or three distal granules; O. fuscipes has two to four, O. bicolor and O. iraqus sp. n. have four or five, and O. scrobiculosus has three to five distal granules.

A convenient way of distinguishing species is also the coloration of the femur and patella of legs and pedipalps, which may be yellow ( O. scrobiculosus ) or black ( O. feti sp. n. and O. zagrosensis sp. n.). However, examination of larger collections indicates that this can be used only as a supplemental character and only in adult specimens. It is highly variable in juveniles, and, furthermore, it often is part of sexual dimorphism. A notable example is O. jalalabadensis sp. n. with yellow males and black females.

Hirsuteness of metasomal segments and telson is used to characterize O. danielleae (Lourenço & Vachon, 1997) and O. monodi (Lourenço & Vachon) . Of the examined species only specimens of O. feti sp. n., O. gromovi sp. n., and O. heratensis sp. n. are markedly hirsute. Apart from these species, O. zagrosensis sp. n. is notable in having the metasoma ventrally glabrous and dorsally hirsute on the margins, especially of the fifth segment, either with long hairs (allotype) or short, inconspicuous hairs (holotype and paratype).

Granulation and presence of carinae on the sixth and seventh mesosomal segments are so highly variable in relation to ontogeny and sex that they can be confidently discarded as possible characters.

Based on the assessment of variability of individual features, I have defined eight basic characters that permit either differentiation of species or of species groups within which it is possible to use also supplemental characters that are to some extent variable. These eight characters can be regarded as stable in adults (the problem of juveniles is so complex in this genus that their identification is often impossible) except for the bristlecombs on legs, which turn out to be variable in two studied species and in Orthochiroides are sexrelated.

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Scorpiones

Family

Buthidae

Genus

Orthochirus