Buthus chambiensis, Kovařík, 2006

Kovařík, František, 2006, Review of Tunisian species of the genus Buthus with descriptions of two new species and a discussion of Ehrenberg s types (Scorpiones: Buthidae), Euscorpius 34 (34), pp. 1-16 : 1-3

Buthus chambiensis , sp. n.

( Figs. 1–5 , Table 1)

Type locality and type repository. Tunisia, Kasserine Province, Jebel Chambi Mts. , 24 km W Kasserine ( Fig. 1 ); author’s collection ( FKCP) .

Type material. Tunisia, Kasserine Province, Jebel Chambi Mts. , 24 km W Kasserine, 23–24 May 1999, 1♂ imm. (paratype), leg. M. Kafka, 29–30 May 2005, 1♂ (holotype) , 2♀ 1 imm. (allotype and paratypes), leg. F. Kovařík.

Etymology: Named after the type locality.

Diagnosis: Total adult length 60–70 mm. Legs, metasoma, and pedipalps uniformly yellowish brown, mesosoma and carapace darker but without noticeable bands, mesosomal sagittal carina black. Movable fingers of pedipalps bear 11 or 12 rows of granules with one internal and one external granule and three distal granules. In female, the segments of pedipalps, namely chela, are wider than in male; chela length to width ratio 5.2 in males, 3.4 in females. Pectines with 26–28 teeth in females, 29–33 in males.

Description: The adult male holotype is 62.3 mm long. Measurements of the carapace, telson, segments of the metasoma and segments of the pedipalps, and numbers of pectinal teeth are given in Table 1. Legs, metasoma, and pedipalps are uniformly yellowish brown, mesosoma and carapace are darker but without noticeable bands, and the sagittal carina on the mesosoma is black. For habitus see Figs. 2–5 .

Mesosoma and carapace: The mesosoma is granulated, with three median carinae, and the seventh segment ventrally bears four inconspicuous carinae. The carapace is sparsely granulated, with carinae typical for the genus Buthus ( Fig. 2 ). Pectinal teeth number 26–28 in females and 29–33 in males.

Metasoma and telson: The first segment bears 10 carinae, the second through fourth segments bear eight carinae (the lateral surface of the second and third segments bears a row of granules that exceeds one-half of the segment length but does not form a complete carina). The fifth metasomal segment has five carinae. The ventrolateral carinae of the fifth segment terminate in two lobes. The ventral carinae on the second and third segments of females posteriorly bear two or three large granules. The surface between carinae is finely granulated, especially in males, may be smooth in females. The telson is bulbous, with the aculeus as long as or shorter than the vesicle.

Legs: Tarsomeres of the legs I to III have very dense bristlecombs. The legs IV are only hirsute. All legs have tarsomeres, tibia, and patella hirsute also on the ventral surfaces. Tibial spurs of legs III and IV are moderately developed.

Pedipalps: The movable fingers bear 11 or 12 rows of granules that have one internal and one external granule and three distal granules. The chela is smooth, males (including immature) may have smooth carinae and on the femur and patella, granulate carinae. Females have wider segments of pedipalps, especially the chela, than males. The chela length to width ratio is 5.2 in males and 3.4 in females.

Affinities. The described features distinguish Buthus chambiensis , sp. n. from all other species of the genus. A key to the Tunisian species of the genus is presented below.

B. chambiensis , sp. n. is easily distinguished from B. tunetanus and B. dunlopi , sp. n. by coloration and sexual dimorphism. Whereas the males of B. tunetanus and B. dunlopi , sp. n. have the chela as wide as or wider than females ( Figs 16 and 18 ), in B. chambiensis , sp. n. the chela is markedly narrower in the male than in the female ( Figs. 2 and 4 , Table 1). Recognition of species within the Buthus occitanus complex (Lourenço, 2002, 2003, 2005) should employ sexual dimorphism as a criterion that allows to divide the complex into groups.

Another Tunisian species is B. paris , whose presence in the steppes around Le Kef I was able to verify during the 2004 and 2005 trips. This species has sexual dimorphism similar to B. chambiensis , sp. n., in which, however, the chela of both sexes is markedly narrower than in B. paris ( Figs. 2–5 ). Other differences are given in the key below.

In the neighboring Algeria there occurs B. tassili Lourenço, 2002 , which differs from all Tunisian species in having the telson and the fifth metasomal segment dark.

The species in all respects closest to B. chambiensis , sp. n. is Buthus barcaeus Birula, 1909 , comb. n. from Libya ( Fig. 6 ), which, however, is larger and has differently colored mesosoma, more bulbous telson, and more densely hirsute legs. This latter species is here elevated to the species status according to the current recognition of former Buthus occitanus as a species complex.

Figures

Figure 1: Type locality of Buthus chambiensis sp. n. (Tunisia, Kasserine Province, Jebel Chambi Mts., 24 km W Kasserine).

Figure 2: Buthus chambiensis sp. n., ♂ holotype, dorsal aspect.

Figure 3: Buthus chambiensis sp. n., ♂ holotype, ventral aspect.

Figure 4: Buthus chambiensis sp. n., ♀ allotype, dorsal aspect.

Figure 5: Buthus chambiensis sp. n., ♀ allotype, ventral aspect.

Figure 6: Buthus barcaeus Birula, 1909, comb. n., immature ♀ from Libya (Tarabulus Province, Abu Qurayn, 31°26´N, 15°14'E, ca. 52 m a. s. l., 14 April 2003, leg. M. Kaftan).

Figure 16: Buthus tunetanus, ♂, dorsal aspect.

Figure 18: Buthus tunetanus, ♀, dorsal aspect.