Chaerilus annapurna, Lourenco & Duhem, 2010

Lourenco, Wilson & Duhem, Bernard, 2010, The genus Chaerilus Simon, 1877 (Scorpiones, Chaerilidae) in the Himalayas and description of a new species, ZooKeys 37 (37), pp. 13-25 : 16-23

Chaerilus annapurna sp. n.

urn:lsid:zoobank.org:act:6EB5ECF8-DBEF-4120-BB45-A3CAA50E4FCC

Figs 12–29

Diagnosis. Species of moderate size in relation to that of the other species in the genus, 49 to 55 mm in total length. General coloration reddish-yellow, marked intensely with variegated brownish spots. The exocuticular pigmentation becomes darker with age and finally turns blackish. This phenomen has already been observed in several other groups of scorpions ( Lourenço and Cloudsley-Thompson 1996). However, in the present case, it was also observed among juveniles. This would suggest that intermolt periods are rather long. Carapace moderately narrowed toward the anterior edge; better marked in females; acarinate and smooth in males; moderately granulated in females; anterior margin straight; furrows shallow in males, moderately deep in females.

Figures 5–ΙΙ. Chaerilus truncatus from India. 5–6 Sternum, genital operculum and pectines, male and female 7–8 Metasomal segment V and telson, lateral aspect, male and female. 9–ΙΙ Chaerilus anthracinus Pocock (= C. truncatus ), male lectotype and female paralectotype. 9–Ι0 Metasomal segment and telson, lateral aspect, male and female ΙΙ Cutting edge of movable finger with rows of granules, male (scales = 3 mm).

Metasomal carinae moderately marked in males; strongly marked in females; ventral carinae obsolete on segment I, weakly marked on segment II; latero-ventral and ventral carinae on segments IV–V composed of strong spinoid granules; other carinae with moderately marked spinoid granules. Telson with an elongated pear-like shape; dorsal surface strongly depressed in males, only slightly in females. Male pedipalps strongly elongated in comparison with female pedipalps; chela fingers strongly granulated in males, in particular on the ventral surface of movable finger; dentate margins of fixed

Ι5

Ι3

Figures Ι2–Ι5. Chaerilus annapurna sp. n. Ι2–Ι3 Carapace, dorsal aspect, male holotype and female

paratype Ι4–Ι5 Sternum, genital operculum, pectines and sternite 3. Idem 12–13 (scales = 3 mm).

and movable fingers with 10–12 (11–13) rows of granules. Pectinal tooth count 4–5 in males, 3–4 in females. Genital operculum plates have a sub-oval shape. Trichobothriotaxy of type B, orthobothriotaxic. Hemispermatophore of fusiform type, with the distal lamina short and curved on its distal portion.

Etymology. The specific name is placed in apposition to the generic name, and refers to the Annapurna Mountain, in the vicinity of which the new species was found, and seems to be endemic.

Material. Nepal, Region of Naudanda, N. of Lakhne, Kaski Gandaki, 2150 m, under large flat stones, 26/V/1996 (H. Tillak), 1 male holotype; Rice fields, 1450 m, under large flat stones, VI/1997 (H. Tillak), 1 male (pre-adult) paratype; 1350–1450 m, under large flat stones, VIII/1999 (H. Tillak), 1 male, 1 female paratypes. NW. of Gorkha, 2000 m, 25/VIII/1980 (B. Lasale), 1 male (juvenile) paratype. Pokkara, 1100 m, station n°4, 31/VII/1970 (J. Martens), 1 female (juvenile), paratype. Holotype and

Figures Ι6–2Ι. Chaerilus annapurna sp. n. Ι6–Ι9 Metasomal segments and telson, lateral aspect. Ι6–Ι 7 Male holotype and male (juvenile) paratype Ι8–Ι 9 Female paratype and female (juvenile) paratype 20–2Ι Cutting edge of movable finger with rows of granules (extremity in detail) and hemispermatophore, male holotype (scales = 3 mm).

paratypes deposited in the Muséum national d’Histoire naturelle, Paris ( MNHN). Female paratype from Pokkara deposited in the collection of J. Martens.

Description. Coloration: Basically reddish-brown, intensely marked with variegat- ed brownish spots, before tegumental sclerification (see diagnosis). Carapace reddishyellow. Tergites of the same colour as carapace; both with variegated spots. Metasomal segments yellowish to reddish-yellow; carinae reddish. Telson yellowish; tip of aculeus reddish. Chelicerae yellowish with diffused variegated spots; fingers and teeth reddish. Pedipalps reddish; chela fingers with the carinae dark to blackish; dentate margins of fingers almost blackish. Legs reddish-yellow with diffused brownish spots. Venter and sternites yellowish; pectines pale yellow. Once tegumental sclerification has taken place general appearance is blackish and only pectines remain pale yellow.

Morphology: Carapace moderately narrowed anteriorly in males, more strongly marked in females; anterior margin straight, almost acarinate; smooth in males, moderately granulated in females; furrows shallow in males, moderately deep in females. Two

20 Wilson R. Lourenço & Bernard Duhem / ZooKeys 37: 13–25 (2010)

24 22 23 26 27 25 28 29

Figures 22–29. Chaerilus annapurna sp. n. Trichobothrial pattern. 22–24 Chela, dorso-external, ventral and internal aspects 25–27 Patella, dorsal, external and ventral aspects, male holotype 28–29 Femur, dorsal aspect and patella ventral aspect, female paratype (scales = 3 mm).

pairs of lateral eyes, and one pair of moderate median eyes, about 1.5 times the size of lateral eyes; median eyes anterior to the centre of the carapace. Tergites smooth in males with moderately marked granulations females; carinae obsolete in both sexes. Sternum pentagonal, longer than wide; genital operculum plates with sub-oval shape. Pectinal tooth count 5– 5 in male holotype, 3– 3 in female paratype. Sternites smooth with spiracles small and oval-shaped; carinae absent from VII. Metasoma: Segments I and II wider than long; segments III to V longer than wide. All the carinae moderately to strongly granular; ventral carinae obsolete on I, weakly marked on II; segments IV and V with latero-ventral and ventral carinae composed of strong spinoid granules. Vesicle very elongated with a pearlike shape, smooth; strongly dorsally depressed in males, only weakly depressed in females; aculeus moderately short. Pedipalps strongly elongated in males in comparison with females; femur with five carinae; internal with spinoid granules. Patella with seven carinae; dorso-external weakly granular; dorso and basal-internal with spinoid granules. Chela with eight carinae, moderately to strongly granular; ventral median carinae moderate.Tegument moderately granular. Fixed and movable fingers longer than manus, strongly granular with 10–12(11–13) rows of granulations on the dentate margins. Chelicerae characteristic of the family Chaerilidae ( Vachon 1963) . Trichobothriotaxy of type B; orthobothriotaxic ( Vachon 1974); femur with 9 trichobothria, patella with 14, and chela with 14. Legs with pedal spurs strongly developed. Tarsi with two rows of spiniform setae. Hemispermatophore of Fusiform Type, with the distal lamina short and curved on its distal portion.

Relationships

Chaerilus annapurna sp. n., shows morphological similarities with Chaerilus truncatus Karsch, 1879 , also described from the Himalayas. The new species can, however, be readily distinguished by the following features: (i) the shape and structure of the telson, strongly depressed dorsally in males, (ii) male pedipalps much more elongated than female pedipalps (see Table I), (iii) movable finger of chela with very strongly marked granulation.

Conclusions

Although this study is only preliminary, some insights have been gained concerning the species of Chaerilus found in the Himalayas and nearby regions of India and Tibet.

Chaerilus truncatus is undoubtedly a rather common species, presenting intra-specific variations that led to the description of several ‘closely associated’ species. Consequently we agree with the decisions of previous authors ( Kraepelin 1899; Kovařík 2000) who placed several of these species in synonymy of C. truncatus .

Chaerilus insignis Pocock, 1894 , remains poorly characterized. Very few specimens are known and the type specimen, originally stored dry, is poorly preserved. The study of more material may show that this species is also conspecific with C. truncatus .

Chaerilus assamensis Kraepelin, 1913 , described from Assam in India, remains poorly known. The type specimen is housed in NZSI, Calcutta, India, and its study by foreign experts is not possible. The recently described Chaerilus tryznai Kovařík, 2000 from China (Tibet), presents few differences from the species described by Kraepelin and may prove to be conspecific. Although Zhu et al. (2008) recently redescribed and properly illustrated C. tryznai , without the study of the type of C. assamensis a final decision cannot be taken in relation to these two species.

Chaerilus pictus (Pocock, 1890) is one of the most peculiar species in the genus (Figs 30–31). Chaerilus gemmifer Pocock, 1894 , is unquestionably a synonym of C. pictus , as already suggested on several museum labels (by Kraepelin and Simon; results not published) for the material deposited in Hamburg and Paris. Kovařík (2000) confirmed this synonymy.

Figures 30–3Ι. Chaerilus pictus from India. Metasomal segment V and telson. 30 Male 3Ι Female (scales = 3 mm).

In conclusion, in the present state of our knowledge, only the following species can be retained as valid for the Himalayas and nearby regions:

Chaerilus truncatus Karsch, 1879

Chaerilus pictus (Pocock, 1890)

Chaerilus assamensis Kraepelin, 1913

Chaerilus tessellates Qi, Zhu & Lourenço, 2005

Chaerilus conchiformus Zhu, Hav & Lourenço, 2008

Chaerilus annapurna sp. n.