Rhacochelifer nonidezi Zaragoza & Hernández-Corral, 2018

Hernández-Corral, Jesús, Zaragoza, Juan A. & Micó, Estefanía, 2018, New species of Pseudoscorpiones (Arachnida) from tree hollows in a Mediterranean oak forest in Spain, Zootaxa 4497 (2), pp. 201-225 : 218-221

Rhacochelifer nonidezi Zaragoza & Hernández-Corral n. sp.

( Figs 6 , 34‒41 )

Type locality. Spain, Castilla y León Community, Salamanca province , La Bastida (40°35′06″N, 06°03′31″W).

Distribution. Spain: Castilla y León Community.

Etymology. The new species is dedicated to the memory of the Spanish zoologist José Fernández Nonídez, to mark the centenary of the publication of his important paper Pseudoscorpiones de España ( Nonídez, 1917).

Diagnosis (Ƌ). Medium-sized Rhacochelifer species without coarser granules on carapace and pedipalps and without elongated keels on posterolateral corners of carapace and tergites in males. Most hemitergites with one lateral, one medial and one discal seta in an anterior position (in addition to postero-marginal setae). Anterior genital operculum with some forked setae. Pedipalpal femur 3.1 times longer than broad, length 0.81 mm; patella 2.2 times longer than broad, length 0.66 mm; chela+ 3.2 times longer than broad, length 1.27 mm. Trichobothrium it distinctly distad of ist and level with est. Tarsus leg I with dorsal and distal margins slightly concave, dorsodistally rounded, without projection, 2.8 times longer than deep.

Type material. ♂ holotype ( CEUA 00106325 ), Spain, Castilla y León Community, Salamanca province, La Bastida (40°35′06″N, 06°03′31″W), 21.VIII.2012, leg. A. García-López, E. Micó & A. Ramírez-Hernández.

Description (Ƌ; ♀ unknown). Medium-sized epigean species ( Fig. 6 ). Body and pedipalps medium brown, legs pale brown Vestitural setae slightly clavate, acuminate on sternites.

Carapace broader than long, granulate, without coarser granules; two transverse furrows, subbasal one more attenuated, posterolateral corners without elongated keels. Setae short, clavate and apically dentate, chaetotaxy: 35:22:9(66), 4 setae on anterior margin, metazone without medial setae. One pair of well developed eyes, diameter 0.07 mm, distance to anterior margin 0.07 mm.

Chelicera ( Fig. 34 ) with 5 setae on hand, ib and db finely dentate, the others smooth; fixed finger with 3 tiny subapical teeth and 3 large medial teeth. Movable finger distally without distinct tubercles; seta gl 0.8 from base; galea ( Fig. 35 ) 0.055 mm long, with 6 apical rami; rallum with 3 blades, the distal one with 8 teeth; serrula exterior with 17 blades.

Tergites I‒X divided, XI partially divided. Tergites without elongated keels on posterolateral corners; in addition to the marginal setae, hemitergites IV‒V with one lateromedial and one discal seta, hemitergites VI‒X with one lateral, one medial and one discal seta ( Fig. 36 ); setae finely dentate apically, chaetotaxy of hemitergites 4‒6:6‒7:5‒6:7:6‒7:7‒8:6‒7:7:7:6‒7, tergite XI 10 (2 long tactile setae, apically acuminate, length 0.21 mm), tergite XII 2. Sternites IV‒X divided, XI partially divided; anterior genital sternite ( Fig. 41 ) with 12 medial acuminate setae and 25 marginal, setae, mostly acuminate except for 8 bifid setae, posterior 13 setae, 5 acuminate internal setae on each side, statumen convolutum as in Fig. 41 , similar to that of R. peculiaris ; hemisternites 4:5:5‒6:5:5:5‒ 6:5‒6(2 long tactile setae), sternite XI 9 (2 long tactile setae, apically acuminate, length 0.20 mm) setae, XII 2 setae.

Pedipalpal coxa with 4 setae on manducatory process (including suboral seta) and 9‒10 setae on disk, leg coxa I 7‒8, II 7, III 8‒9, IV 28 setae.

Pedipalps ( Figs 37‒39 ) with granulation, more pronounced paraxially, without coarser granules. Setae clavate and apically dentate, except those of fingers, which are acuminate. Trochanter with prominent rounded antiaxial hump, femur strongly pedicellate, maximum width at middle. Dental row of fixed chelal finger shorter than that of movable finger, with 29 teeth, movable finger with 33 teeth; venom ducts in both fingers, nodus ramosus proximad et in fixed finger and distad of trichobothrium t in movable finger. Trichobothria as in Figs 38‒39 ; it distinctly distad of ist and very slightly proximad of est; est slightly distad of st; it -est - st almost level.

Tarsus leg I ( Fig. 40 ) with dorsal and distal margins slightly concave, dorso-distally rounded, without projection, claws asymmetric, length of claws 0.145 mm, 1.3 times longer than tarsus width. Leg IV tarsus without tactile seta. All legs with dentate subterminal setae on tarsi.

Measurements (mm) and ratios. Male holotype: Body 2.26. Carapace 0.71/0.82 (0.9). Chelicera 0.28/0.14 (1.9), movable finger 0.19. Pedipalp: trochanter 0.41/0.26 (1.6), femur 0.81/0.26 (3.1), patella 0.66/0.30 (2.2), hand+ 0.74/0.40 (1.9), hand - 0.68 (1.7), movable finger 0.57, chela+ 1.29/0.40 (3.2), chela - 1.18 (3.0); ratio hand+/ movable finger 1.3, femur/movable finger 1.4, femur/carapace 1.1, femur/patella 1.2, hand+/patella 1.1, chela+/ carapace 1.8, chela+/femur 1.6. Leg I: femur+patella 0.47/0.15 (3.2), femur 0.27/0.15 (1.8), patella 0.35/0.14 (2.6), tibia 0.31/0.13 (2.3), tarsus 0.31/0.11 (2.8). Leg IV: femur+patella 0.69/0.23 (3.0), femur 0.24/0.16 (1.5), patella 0.57/0.23 (2.5), tibia 0.48/0.14 (3.4), tarsus 0.34/0.10 (3.4).

Remarks. Five Rhacochelifer species have previously been recorded from the Iberian Peninsula ( Zaragoza 2017a), all occurring in Spain and one of them in Portugal. In four of these species the trichobothria ist and it are close together or separated by no more than one areolar diameter [this characteristic is unknown for Rhacochelifer tingitanus (L. Koch, 1873) , a poorly known species from Morocco that was probably incorrectly assigned to the genus ( Callaini 1988) and whose presence in Spain is highly doubtful ( Zaragoza 2007) (hence its exclusion from the key below)]. In R. nonidezi n. sp. ist and it are distinctly separated, making this species easily distinguishable from the other four Iberian species.

R. nonidezi n. sp. shares with the African species R. similis Beier, 1932 ( Egypt, Libya, Tunisia), R. villiersi Vachon, 1938 ( Morocco) , R. subsimilis Vachon, 1940 ( Algeria, Mali), R. nubicus Beier, 1962 ( Sudan) and R. saharae Beier, 1962 ( Chad, Niger) the absence of coarser granules on carapace and pedipalps, the absence of posterolateral keels on the carapace and anterior tergites, trichobothrium it distinctly distad of ist, a pedipalpal femur with a ratio of 3.0 or less and a length of about 0.70 mm, and the absence of a dorsodistal projection on tarsus I of the male ( Beier 1932, 1962; Vachon 1938, 1940b, 1950). The presence or absence of forked setae on the anterior genital sternite of the male has not been determined in these species. Additionally, R. nonidezi n. sp. shares with R. similis the position of trichobothrium it, level with est, as opposed to distinctly distad of est in the other four species; these two species also have similar pedipalp ratios, but R. nonidezi n. sp. has distinctly larger pedipalp articles (femur 0.65 mm and patella 0.55 mm long in male of R. similis ). Additional differences are provided by the ratios of the tibia and tarsus of male leg I, which are, respectively, 2.3 and 2.8 in R. nonidezi n. sp. and 3.0 and 2.9 in R. similis , and in the tarsus shape, which is distally dilated in R. similis ( Beier 1932: fig. 2). R. nonidezi n. sp. is close to R. saharae in some measurements, but the latter has a more robust pedipalpal femur and chela [femur 2.7, chela (without pedicel?) 2.5 in R. saharae ], the tarsus of male leg I distinctly deeper distally ( Vachon 1950: fig. 12), as opposed to proximad of the middle in R. nonidezi n. sp. ( Fig. 40 ), and in the position of trichobothrium it, distinctly distad of est, halfway between est and et in R. saharae ( Vachon 1938, fig. 11) (slightly proximad of est in R. nonidezi n. sp.).

R. nonidezi n. sp. shares the presence of forked setae on the genital opening of males with R. pinicola ( Spain: mainland, Canary Islands), R. gracilimanus (Canary Islands) ( Mahnert 1980; 1993) and the African species R. tenuimanus Heurtault, 1971 and R. tibestiensis Heurtault, 1971 (both from Chad) ( Heurtault 1971). Both R. tenuimanus and R. tibestiensis differ from R. nonidezi n. sp. in having coarser granules on the carapace and pedipalps. The pedipalp of R. gracilimanus is distinctly longer and more slender (male femur 3.6 times longer than broad, length 1.17 mm, patella 2.8x, length 1.05 mm) than that of R. nonidezi n. sp. R. pinicola has a distinctly shorter palp than that of R. nonidezi n. sp. and lacks a medial anterior seta on tergites VI‒X. The presence of forked setae on the anterior genital sternite has been also reported for some cheliferid genera: e.g. Ancistrochelifer Beier, 1951 ( Dashdamirov 2006) , Ellingsenius Chamberlin, 1932 ( Judson 1990, fig. 7) and Mesochelifer Vachon, 1940 ( Mahnert 1981, figs 10a, 10b; Zaragoza 2009, fig. 6).

Figures

FIGURE 41. Rhacochelifer nonidezi n. sp., male holotype, genital area, ventral view. Abbreviations: fs, forked seta; is, internal seta; sc, statumen convolutum.

FIGURES 2–6. Habitus of species from Salamanca province. 2. Neobisium hispanicum n. sp.; 3. Amblyolpium dollfusi Simon, 1898; 4. Beierochelifer peloponnesiacus (Beier, 1929); 5. Rhacochelifer gaeli n. sp.; 6, Rhacochelifer nonidezi n. sp.

FIGURES 34–40. Rhacochelifer nonidezi n. sp., male holotype. 34, left chelicera; 35, galea of movable cheliceral finger of right chelicera, antiaxial view; 36, left hemitergites VI, with detail of seta ls; 37, left pedipalp, minus chela, dorsal view, with details of setae; 38, left chela, dorsal view; 39, fingers of left chela, antiaxial view; 40, tibia and tarsus of right leg I, antiaxial view. Abbreviations: ds, discal seta; gp, glandular pore; ls, lateral seta; ms, medial seta.