Centetostoma scabriculum ( Simon, 1879 )

Martens, Jochen, 2011, The Centetostoma scabriculum complex — a group of three cryptic species (Arachnida: Opiliones: Nemastomatidae), Zootaxa 2783, pp. 35-51 : 39-41

publication ID	https://doi.org/ 10.5281/zenodo.202391
DOI	https://doi.org/10.5281/zenodo.6194503
persistent identifier	https://treatment.plazi.org/id/894A4140-6F44-563C-D4F7-FF2323ADFD1F
treatment provided by	Plazi
scientific name	Centetostoma scabriculum ( Simon, 1879 )
status	sensu stricto

Treatment

Centetostoma scabriculum ( Simon, 1879) View in CoL sensu stricto

Figs 1 View FIGURE 1 , 3 View FIGURES 2 – 4 , 7–8 View FIGURES 5 – 10 , 12 View FIGURES 11 – 13 , 14–18 View FIGURES 14 – 18 , 20–21 View FIGURES 19 – 23 .

Nemastoma scabriculum Simon 1879: 284 View in CoL ; Simon 1881: 90; Roewer 1914: 150; Roewer 1919: 169; Roewer 1923: 675; Roewer 1951: 130; Kraus 1961: 344; Rambla 1980: 198.

Material investigated. Lectotype 3, FRANCE, Dép. Hautes-Pyrenées, Saint-Sauveur (type locality), collector and collecting date unknown, N 42.867° W 0.017° (syntype series SMF RI /967; this series originally comprised also 1Ƥ C. scabriculum and 13 C. juberthiei sp. n. – see below).

Paralectotype Ƥ, FRANCE, Dép. Hautes-Pyrenées, Saint Sauveur (type locality), collector and collecting date unknown, N 42.867° W 0.017° ( SMF 61245, from syntype series SMF RI /967).

Further material investigated. 13, Dép. Pyrénées-Atlantiques, St. Martin, S of Arette, la Pierre, 1900 m, N 42.97° W 0.73°, J. Martens leg. 20.8.1996 (CJM 3807); 2Ƥ, Dép. Pyrénées-Atlantiques, Pic du Midi d'Ossau, 2700–2880 m, N 42.843° W 0.438°, K. Thaler leg. 13.7.1982 (CJM 3917); 1Ƥ, Dép. Pyrenées-Atlantiques, Col du Pourtalet, Ref. Piombie, 2100 m, N 42.8° W 0.416°, K. Thaler leg. 13.7.1982 (CJM 3916); 153 8Ƥ Dép. Pyrenées- Atlantiques, Col du Pourtalet, 1800 m, N 42.805° W 0.416°, J. Martens leg. 6.9.1967 (CJM 657); 13, Dép. Pyrénées-Atlantiques, E of Col d´Aubisque, 1600 m, N 42.996° W 0.341°, W. Schawaller leg. 1.9.1986 (CJM 2684); 13 1Ƥ, Dép. Pyrénées-Atlantiques, Laruns, Arrens, E of Col d'Aubisque, 1600 m, N 42.996° W 0.218°, K. Thaler leg. 14.7.1982 (CJM 3918); 13, Dép. Hautes-Pyrénées, Gavarnie, Fagetum, 1400 m, N 42.733° W 0.01°, P. Beron leg. 1.9.1967 (CJM 3699); 223 11Ƥ, Dép. Hautes-Pyrénées, Cirque de Gavarnie, 1600–1650 m, N 42.683° W 0.006°, J. Martens leg. 26.9.1979 (CJM 2594); 236Ƥ, Midi-Pyrénées, Dép. Hautes-Pyrénées, SW Lannemezan, Val d´Estaragne near Lac de Cap-de-Long, 2050–2150 m, N 42.816° E 0.141°, J. Martens leg. 30.8.1978 (CJM 1771); – SPAIN. 73 2Ƥ, Aragón, Prov. Huesca, Parque Nacional de Ordesa-Monte Perdido, close to the town of Torla, 1400 m, Fagus forest, N 42.633° W 0.1°, J. Niethammer leg. 29.5.1972 (CJM 1796); 83 12Ƥ, same locality, 1850 m, Fagus forest, N 42.633° W 0.1°, J. Niethammer leg. 29.5.1972 (CJM 1799); 1Ƥ, same locality, Torla, N 42.633° W 0.1°, J. Niethammer leg. 24.5.1972 (CJM 1801); 13 2Ƥ (label indication: 233Ƥ), Parque Nacional de Ordesa-Monte Perdido, Refugio de Góriz, [original label: Zentralpyr., Refugio de Golic], N 42.656º W 0.089°, H. Franz leg. 10.8.1955 ( SMF 11668).

Taxonomy. Within the scabriculum complex there are two species which carry a spur on the palp patella medio-distally, scabriculum sensu stricto and a hitherto undescribed species from the eastern Pyrenees. The scabriculum syntype series contains a male of each of these species that possess this spur. According to the presented material ( Fig. 1 View FIGURE 1 ) both species are strictly allopatric and according to locality a male and the female were selected as representatives of N. scabriculum sensu stricto and the male fixed as a lectotype. The third specimen of the series (13) belongs to the species of the eastern Pyrenees and apparently does not originate from the locality indicated, Saint-Sauveur. This species is described below as new based on fresh material (see C. juberthiei sp. n.).

Diagnosis. A Pyrenean species of Centetostoma . Apo of male basichelicerite moderately split at medial side ( Fig. 8 View FIGURES 5 – 10 ); with a strong spur on palpal patella medio-distally ( Figs 20–21 View FIGURES 19 – 23 ); span of wings on penial truncus broad, but less than those of S. ventalloi and with no mensural overlap ( Figs 12 View FIGURES 11 – 13 , 14–18 View FIGURES 14 – 18 ).

Measurements. Leg II (3, Ƥ in parentheses): Fe 1.25 (1.25), Pt 0.3 (0.3), Ti 0.9 (0.9), Mt 1.75 (1.7), Ta 1.4 (1.3). Body length: 1.4–1.7, n=10 (1.7–1.9, n=3). Span of truncus wings: 0.14–0.21 (n=5, Figs 14–18 View FIGURES 14 – 18 ).

Description. Body ( Fig. 3 View FIGURES 2 – 4 ): Body narrowest at front, towards the rear end slightly enlarged laterally, most significant at rear third of body; entirely black in adults several weeks after moult to adulthood; older adult specimens encrusted with a thin layer of secretion, which – at least after storage in alcohol – is opaque whitish, which more or less camouflages sculpture of the body’s surface.

Dorsal scutum ( Fig. 3 View FIGURES 2 – 4 ): With a distinct armature of well-defined button-like tubercles, quite large and positioned in only moderately regular rows. Along an imaginary median line from the rear eye tubercle to the rear end of the dorsal scutum there are about 27–30 individual tubercles not touching each other; intermediate space between tubercles about tubercle’s diameter. Rear end of scutum with a saw-like row of blunt longish tubercles. On area I–V of the dorsal scutum one pair each of larger und slightly higher tubercles, the inter-distances enlarging towards the rear end of the scutum.

Tuber oculorum ( Fig. 3 View FIGURES 2 – 4 ): Anterior end on the front margin of the dorsal scutum; irregularly armed with two longer (front) to shorter (middle and rear) blunt tubercles.

Supracheliceral lamellae ( Fig. 3 View FIGURES 2 – 4 ): Split into several longish and upwards-extended comb-like structures, each single tooth armed with a short spiny brush on top.

Chelicerae ( Figs 7–8 View FIGURES 5 – 10 ): For male only; basal segment dorso-distally with large bulky frontad-directed Apo, markedly broadened at basis, slightly surpassing the dorso-frontal margin of chelicera’s basal segment; no marked incision at the dorsal part of the Apo (medial and lateral view; Fig. 7 View FIGURES 5 – 10 ). In dorsal view, Apo moderately indented at medial side, the curvature forming an approximately right angle, quite obtuse in Fig. 8 View FIGURES 5 – 10 . In medial view ( Fig. 7 View FIGURES 5 – 10 right) the top of the Apo rounded, the basal part notably broadened and its medial side deeply carved, protected by a row of strong bristles. Its upper margin is slightly bent to the medial side. Latero-distal side of the basichelicerite and the whole Apo covered with strong bristles ( Fig. 7 View FIGURES 5 – 10 left).

Pedipalp ( Figs 20–21 View FIGURES 19 – 23 ): Moderately compact, largest of the three species treated here; Fe slightly enlarged towards distal end, Pt ventrally slightly thickened. Fe to Ta covered with sparse (Fe) to more dense (Pt, Ti, Ta) array of bristles, most of them of the clavate glandular type. There is a distinct medial spur on the distal end of the male Pt which is lacking in the female.

Legs: Short in terms of nemastomatid morphology. Fe, Pt and Ti of leg I, III and IV slightly inflated, leg II slen- der and un-inflated, Fe I from basis to distal end slightly enlarged; Fe, Pt and Ti of all legs with minute evenly distributed acute spines. Pseudoarticulations of femora I–IV (3, Ƥ in parentheses): I 1–2 (1–2), II 5–6 (3–4), III 2–3 (2–4), 3–5 (3–6).

Ventral side: Operculum genitale and free sternites with scattered small tubercles, on the sternites only laterally as a short row, on corona analis more densely packed and larger; Cx pro- and retro-laterally with a scattered row of 7–11 blunt tubercles each.

Genital morphology ( Figs 12 View FIGURES 11 – 13 , 14–18 View FIGURES 14 – 18 ): Truncus penis extremely thin and slender, at the basis bulb-like inflated and medially incised, the two portions of penial muscles are confined to one half of the bulb each. Truncus distad of the bulb enlargement parallel-sided ( Fig. 12 View FIGURES 11 – 13 ). Lower contour of the individual wing is oblique, the upper one mostly horizontal ( Figs 14, 18 View FIGURES 14 – 18 ), often with a slight upward turn ( Figs 16–17 View FIGURES 14 – 18 ); a downward turn also occurs but probably only artifactually ( Fig. 15 View FIGURES 14 – 18 ). Wing span from tip to tip is markedly smaller than in C. ventalloi ( Figs 24– 29 View FIGURES 24 – 29 ) with no mensural overlap (see Measurements). Glans is broadest just above the wings ( Figs 14, 17 View FIGURES 14 – 18 ) or in the distal half ( Figs 15–16, 18 View FIGURES 14 – 18 ), continuously tapering towards the pointed stylus; seminal opening on tip of stylus.

Distribution ( Fig. 1 View FIGURE 1 ). Small area in the western part of the French and Spanish side of the Pyrenees. Recently collected material ranges from Pyrenées-Atlantiques (E of Col d’Aubisque: western-most point) to Hautes- Pyrenées (SW Lannemezan, Val d´Estaragne: eastern-most point). The scabriculum type locality, Saint-Sauveur, is situated in the eastern part of the species’ area. From the Spanish side of the Pyrenees C. scabriculum sensu stricto is only known from the province of Huesca, two localities in the Parque Nacional de Ordesa-Monte Perdido. According to the taxonomy advocated here, these series represent the first verified records for the Spanish fauna.

Older unconfirmed records of “ scabriculum ” refer to Guarda ( Portugal; Bacelar 1928), Prieto (2003) does not mentioned specific records of Centetostoma ; he just followed the view of Kraus (1961). Rambla & Perera (1989) and Rambla (1998) recorded eleven localities from the province of Huesca, most of them west of Ordesa valley and, consequently, these latter records probably all do refer to C. scabriculum sensu stricto. Presently, the distributional area of C. scabriculum sensu stricto seems to be strictly allopatric to the eastern species C. ventalloi but the western-most locality of the latter species (valley of Neste de Couplan river, SW of Lannemezan) is only a few kilometres apart.

Ecology. Ten records indicate an altitudinal range from 1400–2800 m (vertical belt 1400 m) and among them five records between 1400–1800 m, three above 2000 m. The species occurs in montane forest, often in open places, under rocks and stones, also in chalky, relatively dry areas ( St. Martin, S of Arette). Above the timberline, C. scabriculum lives in open grassland or in nearly bare alpine rock debris under stones. Due to little sampling in high altitude, its upper limit is unknown but may not reach far beyond 2800 m, the highest record for the whole species complex at present.