Chaerilus stockmannorum, Kovařík & Lowe & Šťáhlavský, 2018

Kovařík, František, Lowe, Graeme & Šťáhlavský, František, 2018, Three new Chaerilus from Malaysia (Tioman Island) and Thailand (Scorpiones Chaerilidae) with a review of C cimrmani C sejnai and C tichyi, Euscorpius 268, pp. 1-27 : 19-25

Chaerilus stockmannorum sp. n.

( Figs. 35–36, 69–104, 106–107, 111–112, 119–120, Table 2) http://zoobank.org/urn:lsid:zoobank.org:act:7368D4

50-5471-47CB-8D52-CB93F25DB21F

TYPE LOCALITY AND TYPE REPOSITORY. Thailand, Trang, 7.565100°N 99.623855°E; FKCP .

TYPE MATERIAL. Thailand, Trang, 7.565100°N 99.62 3 855°E, 2♂ (1482) 1♀, local collector .

ETYMOLOGY. The specific epithet honors Mark Stockmann and his wife Britta ( Germany) for their invaluable contributions to the knowledge of the worldwide scorpion fauna.

DIAGNOSIS. Total length 45–50 mm. Two pairs of lateral eyes and one pair of median eyes. Chela length /width ratio in males 2.27–2.80. Movable and fixed fingers of pedipalp with 11 imbricated granule rows. Fingers straight. Chela of pedipalp with 8 carinae. Pectinal teeth number 6 in males and 4 in female. Carapace and tergites sparsely granulated in male and densely granulated in female. All sternites smooth without carinae and granules in both sexes. First metasomal segment with 8 or 10 carinae, second to fourth segments with 8 carinae, ventral metasomal carinae absent on metasomal segment V. All metasomal segments rather densely granulated including dorsal surfaces.

DESCRIPTION. Total length 45–50 mm of both sexes. Two well developed pairs of lateral eyes and one pair of median eyes. The chelicerae ( Figs. 35–36) are finely granulated, yellow and strongly reticulate, anteriorly black. For the position and distribution of trichobothria, see Figs. 96–101. For measurements, see Table 2.

COLORATION ( Figs. 106–107). The color is reddish brown, spotted; pedipalp chela and telson are red.

CARAPACE AND MESOSOMA ( Figs. 73–76). The carapace is covered with large granules which do not form carinae. The anterior margin of the carapace is almost straight to weakly concave. The mesosomal tergites are irregularly sparsely granulated in males and densely covered by large granules in the female. All sternites are smooth without carinae and granulation. Sternite V

with smooth patch developed. Pectinal teeth number 6 in males and 4 in female.

METASOMA AND TELSON ( Figs. 85–92). The first metasomal segment bears 8 or 10 carinae, the second to fourth bear eight carinae, and the fifth segment bears seven carinae including the ventromedian carina which posteriorly bifurcates in a "Y" configuration. All carinae are composed of large, sparse granules. All metasomal segments are sparsely hirsute and rather densely granulated including dorsal surfaces.

The telson is elongate, densely granulate and sparsely hirsute.

PEDIPALPS ( Figs. 93–104). The pedipalp chela is wide and swollen in the male. The movable and fixed fingers of pedipalp bear 11 imbricated rows of granules. The chela has eight marked carinae. The patella has five marked carinae and the femur has four or five granulated carinae. The spaces between carinae are densely covered by granules on the femur and patella. The chela is densely granulated anteriorly and has reticulate fine granulation patterns centrally and posteriorly. LEGS ( Figs. 77–84). The legs are sparsely hirsute, without bristlecombs and carinae. The patellae have several strong spines dorsally. The tarsomeres bear two rows of spiniform setae and 3 – 5 outer spiniform setae. Spiniform setae formula is 7/8: 7–8/7–9: 8–9/8–9: 8–9/8– 10 (omitting outer spiniform setae).

HEMISPERMATOPHORE ( Figs. 111–112). Fusiform, with relatively large capsule region (ca. 1 mm), and distal lamina of moderate length (ca. 725 µm), angled posteriorly and apically rounded. Sperm hemiduct of capsule well sclerotized, with long posterior carina and shorter anterior carina.

KARYOTYPE ( Figs. 119–120). We analyzed one male paratype. We identified 2n= 186 in this specimen ( Fig. 119). During metaphase I we observed 89 bivalents, one trivalent and the chain from five chromosomes ( Fig. 120). We did not observe chiasmata during meiosis in this species.

AFFINITIES. Chaerilus stockmannorum sp. n. is reliably distinguished from all other Chaerilus species by the following unique combination of characters: total length 45–50 mm; movable and fixed fingers of pedipalp with 11 imbricated granule rows; chela length/ width ratio in males 2.27–2.80; chela fingers straight in male.

The type locality of C. stockmannorum sp. n. lies within the area of distribution of C. cimrmani Kovařík, 2012 which can be distinguished morphologically from C. stockmannorum sp. n. by the shape of the chela of males. Figures 95 versus 105 show that the male of C. cimrmani has a wider chela with shorter fingers.

Comparative Chaerilus material examined, including new records ( FKCP).