Centetostoma juberthiei, Martens, Jochen, 2011

Martens, Jochen, 2011, The Centetostoma scabriculum complex — a group of three cryptic species (Arachnida: Opiliones: Nemastomatidae), Zootaxa 2783, pp. 35-51 : 47-48

Centetostoma juberthiei sp. n.

Figs 1 , 4 , 9–10 , 13 , 22 , 30–32 .

Holotype 3 FRANCE. Dép. Pyrénées-Orientales, SW Quillan, Lac des Bouillouses, 1900–2100 m, N 42.716° E 1.983°, J. Martens leg. 20.6.1972 (CJM 7004).

Paratypes 103 10Ƥ; same data as holotype (CJM 1792; originally together with 13 C. ventalloi , see above); 263 18Ƥ, Dép. Pyrénées-Orientales, Prats-de-Mollo-la-Preste, NE Col d’Ares, border of open pasture and Pinus forest, 1501 m, N 42.375° E 2.456°, A. Schönhofer leg. 2.10.2009 ( CAS 576, together with 13 C. ventalloi , see above).

Further material investigated. FRANCE. 13 from syntype series C. scabriculum SMF RI /967, now in SMF 61246; this series originally comprised also 13 1Ƥ C. scabriculum , see above); 13, Dép. Ariège, 30 km S St.Girons, Port d'Aula (road D703), 1500- 1500 m, N 2.456° E 1.116°, J. Martens leg. 3.9.1967 (CJM 782); 23 2Ƥ, Midi-Pyrénées, Dép. Ariège, SE of Col de Port, ESE of St. Girons, Forêt de Sanzet, 1200–1300 m, N 42.896° E 1.449°, J. Martens leg. 26.8.1978 (CJM 1726); 2Ƥ, Dép. Pyrénées-Orientales, above Mt. Louis, Tet valley, Kiefernwald, 1700 m, N 42.506° E 2.1°, W. Schawaller leg. 28.8.1980 (CJM 2672); 13 1Ƥ, Dép. Pyrénées-Orientales, 28 km W of Céret, Pic de Costabonne, 2400–2465 m, alpine grassland, N 42.416° E 2.466°, J. Martens leg. 25.8.1997 (CJM 3633); 63 1Ƥ, Dép. Pyrénées-Orientales, below Col d’Ares, grass, small brook, below stones, 1500 m, N 42.366° E 2.45°, J. & B. Martens leg. 26.8.1984 (CJM 2626); 1Ƥ, Dép. Pyrénées-Orientales, Mont Canigou, high alpine habitat, appr. N 42.519° E 2.457°, H. Franz leg. 25.8.1953 ( SMF 11728/1); 2Ƥ, Dép. Pyrénées-Orientales, Mont Canigou, 2200–2500 m, appr. N 42.519° E 2.457°, H. Franz leg. 25.8.1953 ( SMF 11749/2); 13, Dép. Pyrenées-Orientales, Massif du Canigou, Gomp de Cady, 2400 m, N 42.516° E 2.459°, K. Thaler leg. 25.8.1982 (CJM 3919); 1Ƥ, Dép. Pyrénées-Orientales, Haut Vallespir, NW Prats-de-Mollo, 1600 m, N 42.409° E 2.475°, J. Martens leg. 16.7.1994 (CJM 3895); 13 1Ƥ, Dép. Pyrénées-Orientales, Tech valley, SW of Amélie-les-Bains, la Preste, 1300 m, N 42,4° E 2.488°, J. Martens leg. 23.8.1997 (CJM 3624); 13 2Ƥ, Dép. Pyrénées-Orientales, between Ax-les-Thermes and Querigut, 1150 m, N 42.708° E 2.55°, J. Martens leg. 12.8.1993 (CJM 3422); 13, Dép. Pyrénées-Orientales, Haut Vallespir, above Serralongue, 950–1100 m, N 42.383° E 2.55°, J. Martens leg. 1.– 30.8.1993 (CJM 3410).

Taxonomy. Nemastoma scabriculum Simon, 1879 turned out to be a composite entity embracing three distinct species taxa. Two of this group are already named ( scabriculum Simon, 1879 , ventalloi Mello-Leitao, 1936 ; see above), and the third one is described here as a new species.

Diagnosis. A Pyrenean species of Centetostoma . Apo of male basichelicerite smoothly indented at medial side ( Fig. 9 right); with a small spur on palpal patella medio-distal ( Fig. 19 ), wings on penial truncus only slightly exposed sideward, rounded, small and much less distinct than in C. scabriculum and C. ventalloi ( Figs 30–32 ).

Measurements. Leg II (3, Ƥ in parentheses): Fe 1.05 (1.1), Pt 0.3 (0.4), Ti 0.8 (0.8), Mt 1.25 (1.3), Ta 1.15 (1.25). Body length: 1.4–1.7, n=11 (1.6–1.75, n=8). Span of truncus wings: 0.08–0.09 (n=3, Figs 30–32 ).

Description. Body ( Fig. 4 ): Body narrowest at front, towards the rear end slightly enlarged laterally, most significant at rear third. Entirely black in adults several weeks after moult to adulthood; older adult specimens are encrusted with a thin layer of secretion which – at least after storage in alcohol – is opaque whitish and more or less camouflages sculpture of the body’s surface.

Dorsal scutum ( Fig. 4 ): With a distinct armature of well-defined button (lens)-like tubercles, quite large and positioned in only moderately regular rows. Along an imaginary median line from the rear end of the eye tubercle to the rear end of the dorsal scutum there are about 23–25 individual tubercles not touching each other; intermediate space between tubercles slightly smaller than tubercle’s diameter. Rear end of scutum with a saw-like row of acute tubercles, considerably longer than their diameter. On areae I-V of the dorsal scutum one pair each of larger und slightly higher tubercles than the general surface granulation, the inter-distances enlarging towards the rear end of the scutum.

Tuber oculorum ( Fig. 4 ): Its anterior end at the front margin of the dorsal scutum; irregularly armed with two longer (front) to shorter (middle and rear) blunt tubercles, slightly broadened distally.

Supracheliceral lamellae ( Fig. 4 ): Split into several longish and upwards-extended comb-like structures, each tooth armed with a short spiny brush on top.

Chelicerae ( Figs 9–10 ): Male; basal segment dorso-distally with a large rounded frontally directed Apo, extending considerably from the upper side of the basal segment, beyond the front margin of the basis ( Fig. 9 right), in medial/lateral view egg-shaped and continuously rounded dorsally ( Fig. 9 left); in dorsal view ( Fig. 10 ) the Apo is slightly indented from medial side forming a shallow depression, sometimes even less pronounced than in Fig. 10 . Top of the Apo is only rounded, thus a medially overhanging part of Apo is lacking ( Fig. 9 right). Slight armature with long bristles on top and medial side of Apo, moderately strong bristles on the lateral side of the basal segment’s distal half.

Pedipalp ( Fig. 22 ): Moderately compact, covered with sparse (Fe) to more dense (Pt, Ti, Ta) coverage of bristles, most of them of the clavate glandular type. There is an indistinct medial spur on the distal end of the male Pt. Being opaque it is often difficult to see and can even be absent in rare cases (CJM 3422). The spur is not present in the female.

Legs: Short in terms of nemastomatid morphology. Fe, Pt and Ti of legs I, III and IV slightly inflated, in legs III and IV mostly at distal end, leg II slender and un-inflated, Fe II from basis to distal end slightly enlarged; Fe, Pt and Ti of all legs armed with warty irregular tubercles, producing a rugged surface. Pseudoarticulations of femora I–IV (3, Ƥ in parentheses): I 0–1 (1), II 4–5 (3–5), III 2–3 (2–3), 3–5 (3–5).

Ventral side: Operculum genitale shiny, tuberculation scanty, row of tubercles on free sternites only laterally; larger and higher, thus more accentuated, tubercles on corona analis. Cx I-IV pro- and retro-lateral with a scattered row of 8-10 blunt tubercles each.

Genital morphology ( Figs 13 , 30–32 ): Truncus penis extremely thin and slender (most pronounced of the three species treated here), at the basis bulb-like inflated (this part longest of the three species treated here) and medially incised, each lobe with a bundle of penial muscles. Truncus distad of the bulb enlargement most slender (dorsal/lateral view), from there slightly but continuously enlarged to the lateral wings into which the lateral contours turn ( Fig. 13 ). Lower contour is thus quite steep, upper slightly rounded and the wing-like structure is only small. These wings form a shallow pocket. Glans ( Figs 30–32 ) continuously tapering, then slightly enlarging to distal half, again tapering to the pointed stylus, which is not well differentiated. Opening of seminal duct on top of stylus.

Variability: Genital morphology quite stable, especially the alate structures below the glans ( Figs 30–32 ).

Distribution ( Fig. 1 ). All localities are situated in the central and eastern-most part of the Pyrenees in the départments of Ariège (two localities, the western-most one: Port d'Aula, 30 km S St.Girons) and Pyrénées-Orientales (the eastern-most above Serralongue and between Ax-les-Thermes and Querigut). There is a noticeable distributional overlap between C. ventalloi and C. juberthiei sp. n. in the eastern Pyrenees, just northwest and northeast of Andorra, but only in two localities have both species been found in small-scale syntopy, only a single male of C. ventalloi in large series of C. juberthiei sp. n. (Col d’Ares; Lac des Bouillouses) in both. Apparently, there are no mixed colonies comprising both species in approximately equal numbers. For an alleged record of C. juberthiei sp. n. in Saint-Sauveur (Hautes-Pyrenées), see above ( C. scabriculum ).

Ecology. Eleven records for altitudinal distribution range from 1000–2450 m (vertical belt 1450 m), among them four records between 1500–1700 m, two above 2000 m. Forested areas are commonly inhabited, mainly sparsely overgrown places with low vegetation; often under stones. Due to little sampling at high altitude, the upper limit is not well documented.

Derivatio nominis. This well discernible but for long overlooked species is dedicated to M. le Professeur Dr Christian Juberthie, former Director of the Laboratoire souterrain du CNRS at Moulis, Ariège, France. Dr. Juberthie is famous for his fundamental and long-lasting studies on biology, ecology and anatomy of various groups of harvestmen including European cave fauna.

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 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).

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 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 19 – 23. Pedipalps of 3, medial view. 19, 23: Centetostoma ventalloi (19: Val d’Aran, MNRJ 42545, paratype; 23: Lac des Bouillouses, CJM 6844). 20 – 21: C. scabriculum (20: Torla, CJM 1799, 21: Saint Sauveur, SMF 967). 22: C. juberthiei sp. n. (Lac des Bouillouses, CJM 1792).

FIGURES 30 – 32. Centetostoma juberthiei sp. n., glandes penis, dorsal view. 30: Lac des Bouillouses (CJM 1792). 31: Saint Sauveur (SMF 967, lectotype C. scabriculum). 32: SE Col de Port (CJM 1726).