Centetostoma Kratochvíl, 1958

Martens, Jochen, 2011, The Centetostoma scabriculum complex — a group of three cryptic species (Arachnida: Opiliones: Nemastomatidae), Zootaxa 2783, pp. 35-51 : 38

Centetostoma Kratochvíl, 1958

Type species: Nemastoma centetes Simon, 1879 (original designation).

The genus is here defined comprising four species, one from the western Alps ( C. centetes ) and three from the Pyrenees ( C. scabriculum , C. ventalloi , C. juberthiei sp. n.).

Genital morphology ( Figs 11–13 ): Penial truncus straight, at the basis bulb-like enlarged and bifid, thus the two portions of penial muscles confined to one half of the bulb each; truncus slender, more or less parallel-sided, glans symmetrically tapering to the end, opening of the sperm duct at the very tip; below the glans, an alate (wing-like) structure, slender and rounded (in centetes , ventalloi ) or strongly extended and pointed sidewards (in scabriculum , juberthiei sp. n.).

Apophysis of male chelicerae ( Figs 5–10 ): Well developed, concave medially and (only in the Pyrenean species) split into two parts, a distal and a proximal one (from dorsal view).

Pedipalps: Slender, only in two species ( scabriculum and juberthiei sp. n.) with a spur on the patella mediodistally.

Legs: Short in the Pyrenean species, (relatively) longer and considerably more slender in C. centetes .

Armature of the dorsal side ( Figs 2–4 ): Besides a differing granulation covering the scutum, a more or less indistinct tubercle pair is on each area I-V of the scutum; these are strongly developed with additional long thorns only in C. centetes .

Coloration. Depending on age brownish to blackish without silvery marks. This holds true also in C. centetes of the Alps.

Distribution. One species in the western Alps, three at medium to high altitude in the Pyrenees except for the western-most part ( Fig. 1 ).

Figures

FIGURE 1. Pyrenean distribution of Centetostoma scabriculum (squares, blue), C. ventalloi (dots, green) and C. juberthiei sp. n. (triangles, red). Note two sympatric occurrences of C. ventalloi and C. juberthiei sp. n. with overlaying symbols. The western-most overlaying symbols (scabriculum / juberthiei sp. n.) represent the type locality of C. scabriculum (Saint-Sauveur) and denote a false record for C. juberthiei sp. n.

FIGURES 11 – 13. Penes, dorsal view. 11: Centetostoma ventalloi (SW Foix, CJM 1789). 12: C. scabriculum (Col d’Aubisque, CJM 3918). 13: C. juberthiei sp. n. (Col de Port, CJM 1726).

FIGURES 5 – 10. Right 3 chelicerae. 5, 7, 9: lateral (left column) and medial view (right column); 6, 8, 10: dorsal view. 5 – 6: Centetostoma ventalloi (Col de la Core, CJM 1792). 7 – 8: C. scabriculum (Torla, CJM 1799). 9 – 10: C. juberthiei sp. n. (Lac des Bouillouses, CJM 1792).

FIGURES 2 – 4. Dorsal side of body, ♂. 2: Centetostoma ventalloi (Col de la Core, CJM 752). 3: C. scabriculum (Torla, CJM 1799). 4: C. juberthiei sp. n. (Lac des Bouillouses, CJM 1792).