Roncus montsenyensis Zaragoza & Áhlavský, 2008, sp. nov.
Creators: name: Zaragoza, Juan A.
name: Áhlavský, Franti Š Ek Š Ť
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Pseudoscorpiones
Neobisiidae
Roncus
Roncus montsenyensis

description: Roncus montsenyensis sp. nov.
(figs 2–17)
Type material. Male holotype: Spain, Catalonia, Barcelona province, Montseny Natural Park, N41° 45’6.14” E02°26’34.30”, altitude 1137m, in beech leaf-litter, 9 Sept. 2006, lgt. F. Š Ù áhlavský, L. Bouzek & V. Opatová; deposited in DEUA. Paratypes: 2 ɗ and 3 Ψ with the same collection data as holotype, 1 Ψ deposited in DEUA, 1 ɗ in MHNG, 1 Ψ in MNHNP, 1 Ψ in MCNB, 1 ɗ in MNCNM.
Diagnosis. Epigean Roncus of typical roncoid facies, small-medium in size. Carapace longer than broad (ξ: ɗ 1.20×, 0.67/0.55; Ψ 1.21×, 0.67/0.55); epistome moderately prominent, isosceles triangle shape, apex rounded; chaetotaxy: 4-8-6-6=24. Chelicera without granulation at base of movable finger. Tergites I–V: 6– 7:7–11:11:10-11:11. Medial process of coxa I without denticles. Palp femur granulated but without tubercles at the paraxial face, one tiny tubercle at middle of antiaxial face; longer than either chelal finger or carapace; ξ: ɗ 3.94×, 0.72/0.18; Ψ 3.75×, 0.71/0.19. Patella smooth. Chela, ξ: ɗ 3.62×, 1.25/0.35; Ψ 3.34×, 1.21/0.36. Ratio length finger/hand, ξ: ɗ 1.25×, Ψ 1.19×. Five, seldom four, microsetae between trichobothria eb and esb. Distance between trichobothria ib and ist about 2.00×distance ist–it (ξ: 1.85×), distance (ξ) sb–st 0.95× distance b–sb. Leg IV claws with a tiny tooth on dorsal side; subterminal setae with three rami.
Etymology. Named in reference the locus typicus of the species, Montseny Natural Park.
Description. Data correspond to the male holotype, with paratype data in parentheses. Measurements and ratios as in Table 1.
Opisthosomal pleura and legs yellowish, tergites slightly sclerotized. Carapace, chelicerae and pedipalps red-brownish.
Carapace (fig. 2) longer than broad, maximum width at medial third. One pair of reduced eyes with flattened lens 0.075 (0.063–0.070) mm long, situated 0.068 (0.055–0.068) mm from anterior margin. Epistome (fig. 3) obtuse-angled isosceles triangle shaped (more or less pronounced), apex broadly rounded, 0.020 (0.015–0.023) mm long and 0.028 (0.022–0.030) mm wide. Chaetotaxy: 24 (23–25) setae, formula: 4:4:10(9– 11):6. Glandular pores present, three (one to four) on each side between anterior and ocular zones. One microlyrifissure close to each eye and one on each side of the posterior zone.
Coxal area. Manducatory process with 3 (3–4) setae; palpal coxa with 7 (7–9) setae, pedal coxa I with 5– 7 (5–6) setae, II: 5 (6–8), III: 4–5, IV: 7–8 (6–9). Anterior process of coxa I (fig. 13) with short and simple tooth shape, apically pointed, 0.020 (0.015–0.018) mm long and 0.018 (0.015–0.019) mm broad; medial process straight, not prominent, without denticles.
Tergal chaetotaxy I–X: 6:7:11:11:11:11:11:11:11(4 PT):9(4TS) (6–7:7–11:11:10–11:11:11:11–12:10– 11:11:11). Segment XI with 13 setae, 6 of them tactile setae. Anal cone with 2 dorsal and 2 ventral setae. Male genital area with 15 (13–14) setae on sternite II; sternite III with 13 (13–14) setae, 5 (4–5) of them along posterior margin of genital opening; genital opening with 2+2 internal setae. Female genital opening with 8–10 microsetae on sternite II and 12–13 on sternite III. Chaetotaxy of sternites IV–X: 8:13:13:13:13:13:?(sternite X fragmented) (9–10:13–14:13–14:13–15:13–14:13–14:11–13).
Chelicera (figs 4–5) with 6 (6–7) setae on hand and one seta on movable finger, 0.66× (0.60–0.68) from base. The spinneret a flattened hyaline tubercle (slightly lower in males than in females) with 4 silk ducts. Fixed finger with 4 (4–7) apical protuberances and 14 (15–18) medium and small size teeth; movable finger with 3 (2–5) apical protuberances and 12 (9–12) teeth, 4 (2–3) of large size. Flagellum with 8 denticulate blades, length of proximal blade about one third that of the others; serrula exterior with 26 (23–27) blades, serrula interior with 24 (18–23) blades.
Palps (figs 8–12, 14–17), trochanter with one small (small or medium) tubercle and one small protuberance at antiaxial face; with tiny dorsal denticulation in distal half; paraxial face of femur completely granulated, one tiny (almost indistinguishable) tubercle at middle of antiaxial face, one glandular pore mediodistally. Patella smooth, two micropores at base of pedicel, some lyrifissures as drawn in fig. 9. Chela (figs 8,10,16): paraxial face of hand granulated at base of fixed finger, one pore at antiaxial face close to finger base, with significant protuberance (gp, fig. 10); one micropore at base of dorsal face of pedicel. Fixed finger with 61 (54–63) teeth up to the level of trichobothrium ib; nodus ramosus (fig. 11) at level of 5th (4th) distal tooth; distance between trichobothria ib and ist 2.02 (1.64–2.08) times longer than between ist and it; 5 (5, only one male 4) microsetae below trichobothria eb and esb and one (1–2) slightly distal of eb (fig. 12); one lyrifissure at level of trichobothria eb, ib and distal of it. One sensillum near the tip of both fingers. Movable finger with 59 (54–64) teeth up, extending further than teeth of fixed finger, ending just distad of trichobothrium b; distance between trichobothria s b and st 0.92 (0.87–0.97, one female 1.05) shorter than distance b–sb; one sensillum (p 2) close to dental margin, above or slightly proximad of trichobothrium sb, another sensillum (p 1) distad of sb (more or less close to trichobothrium, but always distal); two ventral glandular pores between trichobothria b and sb (gp, fig. 10); one lyrifissure basal of trichobothrium b, one between b and sb and one slightly basal, level with or even distad of sb.
Claws of legs I and IV (fig. 6) with a tiny tooth at middle of dorsal side. Leg IV (fig. 7) tibia TS ratio 0.51 (0.53–0.59), basitarsus TS ratio 0.18 (0.16–0.23), telotarsus TS ratio: 0.31 (0.35–0.39); subterminal setae (fig. 6) 0.063 (0.063–0.071) mm long, with three rami, the longest [L=0.030 (0.030–0.043)] and the next longest [L=0.019 (0.018–0.026)] with some spinules, the shortest [L=0.008 (0.05–0.009, apically broken in some specimens)] smooth.
Distribution. The new species has thus far been found only at the Montseny Natural Park (Barcelona province, Catalonia, Spain) and is probably endemic to that area.
Remarks. Amongst the Roncus species from Spain with a roncoid form [in the sense used by Zaragoza et al. (2007) for the species of the genus with epigean appearance, in contrast to the term parablothroid adopted by Gardini (1982a) for species with a cave-dwelling appearance], R. montsenyensis sp. nov. resembles R. neotropicus Redikorzev, 1937 and R. judsoni Henderickx & Zaragoza, 2005 in having a male palpal femur ratio of about 4.0. However, the latter species differ in having the femur distinctly longer (about 1.00 mm in both), and the palpal microsetae below trichobothria eb -esb are more numerous in R. judsoni (8–10 microsetae). Compared with species with short palpal articles, R. montsenyensis sp. nov. is easily distinguished from R. lubricus L. Koch, 1873 (as defined by Gardini 1983) by the absence of a microsetae group proximal to trichobothrium eb (present in R. lubricus); moreover R. lubricus is probably absent from Spain (Gardini 1983, 2000; Henderickx & Zaragoza 2005; Zaragoza 2007). The differences between the new species and R. cadinensis Zaragoza, 2007 (in Zaragoza et al., 2007), also from Barcelona province, are subtle but consistent: palp trochanter tubercle more pronounced in R. cadinensis, palp smaller and more robust in R. cadinensis (ξ: femur ɗ 3.39×, 0.69/0.20, Ψ 3.45×, 0.77/0.22; chela ɗ 3.34×, 1.17/0.35, Ψ 3.06×, 1.30/0.42); average distance between trichobothria ib and ist 1.85× distance between ist and it (versus average of 1.56 in R. cadinensis), distance (ξ) sb–st 1.13× distance b–sb in R. cadinensis (versus 0.95× in R. montsenyensis); finally R. cadinensis bears only three microsetae below eb and esb, as opposed to five in R. montsenyensis, which emphasizes the importance of this characteristic.
In comparison with the French species of the genus and following Gardini’s keys (1982b, 1991), the new species is readily distinguished from Roncus duboscqi Vachon, 1937 by the palpal femur measurements— 4.24–4.30× (0.89/0.21) in ɗɗ of the French species, 4.00× or lower (0.72/0.18) in R. montsenyensis— and similar differences generally apply to the rest of palp and leg articles. The same is true for Roncus euchirus (Simon, 1879), which also differs in having a large and pointed epistome: 0.035–0.045 mm long (Gardini 1982b), versus 0.015–0.023 mm in the new species.
Among the mainland Italian species, based on the keys of Gardini & Rizzerio (1985, 1986) and Gardini (1991, 1992, 1993), the new species belongs to the group of species with 6 setae on the posterior carapacial margin, a palpal chela (with pedicel) 1.05–1.54 mm long, and lacking tubercles on the antiaxial face of the palpal femur. Within this group, R. montsenyensis resembles R. binaghii Gardini, 1991 and R. caprai Gardini, 1993 in having the palpal femur less that 0.80 mm long, but it differs from both in lacking denticles on the medial process of coxa I. Moreover R. montsenyensis has the palpal patella smooth, whereas in R. caprai it bears evident granulation.
The new species presents more affinities with species from Sardinia. Following Gardini & Rizzerio’s (1987) key, R. montsenyensis can be compared with the species with ratio finger/hand of the chela 0.90–1.35, palp femur without tubercles at the antiaxial face, patella smooth, femur length 0.52–0.78 mm and chela length 0.86–1.30 mm. Roncus abditus (J.C. Chamberlin, 1930) is easily distinguished from the new species by the lower ratios and measurements of the palpal articles (ξ: femur ɗ 3.34×, 0.54/0.16, Ψ 3.11×, 0.54/0.17; chela ɗ 3.25×, 0.91/0.28, Ψ 3.02×, 0.94/0.31; finger ɗ and Ψ about 0.50). Roncus caralitanus Gardini, 1981 differs from R. montsenyensis by the shape of the carapacial epistome (well developed and pointed in the Sardinian species and short and rounded in the Catalonian species; this distinction is also valid for R. cadinensis although it was not mentioned in the description of the latter); carapace almost as long as broad in R. caralitanus and clearly longer in the new species; palps less slender in the Sardinian species (femur ɗ 3.48–3.52×, Ψ 3.54×; chela ɗ 2.88–3.12×, Ψ 2.95×); and Gardini’s figure (1981: fig. 7) shows only one microseta between eb and esb. R. caralitanus has been recorded from the Balearic Islands, Sicily and Sardinia, but according to Gardini (2000) it is probably endemic to Sardinia, the records from the other islands being misidentifications. R. montsenyensis shows more similarity to Roncus grafittii Gardini, 1982 (Gardini 1982a), a troglophilous species with some troglomorphic adaptations (eyes reduced to spots and slender palps). Both species present similar morphometric values for some article of the palps and legs, but, in addition to the reduction of the eyes, some clear differences can be observed: the segments of the pedipalp and legs tend to be more slender in the Sardinian species (e.g. palp femur Ψ 4.27×, palp patella ɗ 2.50×, Ψ 2.54×; leg I tibia ɗ 5.07×, Ψ 5.14×, telotarsus leg I ɗΨ 5.40×, tibia leg IV ɗ 7.26×, Ψ 5.81×, telotarsus leg IV ɗ 5.33×), reflecting modifications to cave life; subterminal setae of telotarsus IV with two rami in R. grafittii, but clearly with three rami in R. montsenyensis; movable cheliceral finger with dorsal-basal granulation in R. grafittii (completely smooth in the new species); distance between trichobothria ib and ist 1.85× (ξ) longer than ist–it in R. montsenyensis and 1.57× (ξ) in R. grafittii, average distance sb–st 0.95× distance b–sb in the new species and 1.86× in the Sardinian species [ratio for R. grafittii calculated from Gardini’s figures (1982a: figs 14,15,17)]; chelal microsetae pattern below eb and esb reduced to two microsetae in the Sardinian species (observed in micrograph of male holotype kindly sent by Dr Giulio Gardini).
description: Published as part of Zaragoza, Juan A. & Áhlavský, Franti Š Ek Š Ť, 2008, A new Roncus species (Pseudoscorpiones: Neobisiidae) from Montseny Natural Park (Catalonia, Spain), with remarks on karyology, pp. 27-40 in Zootaxa 1693 on pages 30-36, DOI: 10.5281/zenodo.180666