Traegaardhia cavernarum Zacharda, 2010

Zacharda, Miloslav, Fong, Daniel, Hobbs Iii, Horton H., Piva, Erminio, Slay, Michael E. & Taylor, Steven J., 2010, 2474, Zootaxa 2474, pp. 1-64 : 26-31

Traegaardhia cavernarum Zacharda , n. sp. ( Figs 17–20)

Material examined

HOLOTYPE: adult female, Italy, Veneto, Massiccio del Monte Grappa, Quero (Belluno), Buso del Marmo Cave (1202 V / BL), 340 m a.s.l., coll. E. Piva, 14.1.2007, deposited in the Museum of Biological Diversity, Ohio State University, Type No. OSAL0007423; paratypes (deposited with holotype): adult female, Italy, Veneto, the Monti Berici Mts, Arcugnano (Vicenza), in the mesovoid shallow substratum habitat (cf. Juberthie 2000), in a grove east of the Moreieta Restaurant (out of the limestone zone), 335 m a.s.l., coll. E. Piva, 29.10.2006, OSAL0007424; adult female, Veneto, the Hills of Conegliano, San Pietro di Feletto (Treviso), Buso dei Zambon Cave (6080 V/ TV), 190 m a.s.l., coll. E. Piva, 17.3.1996, OSAL0007425; adult female, Veneto, Il Montello, Nervesa della Battaglia (Treviso), Tavaran Grando Cave (69 V/ TV), 100 m a.s.l., coll. G. Peretto, E. Piva, 16.11.1997, OSAL0007426; adult male, Veneto, the Hills of Conegliano, San Pietro di Feletto (Treviso), Buso dei Zambon Cave (6080 V/ TV), 190 m, coll. E. Piva, 12.3.1994, OSAL0007427; adult female, Venezia Tridentina, Altopiano dei Sette Comuni, Grigno, Trento, Grotta della Bigonda Cave (243 VT/ TN), 450 m, coll. G. Peretto, E. Piva, 10.3.1996; two adult females, Veneto, Altopiano dei Sette Comuni, Valstagna ( VI), Grotta del Subiolo Cave (135 V/ VI), 169 m, coll. E. Piva, 31.3.1990; adult female, Veneto, the Hills of Conegliano, San Pietro di Feletto (Treviso), Bus dei Tedeschi Cave (1818 V / TV), 100 m, coll. E. Piva, 11.12.1993; adult male, Veneto, Il Montello, Nervesa della Battaglia (Treviso), Bus de le Fratte Cave (1277 V / TV), 132 m a.s.l., coll. M. Bau, B. Bianco, A. Costia, E. Piva, P. & S. Romani, G. Roncolato, 10.2.2008; adult female, Veneto, the Hills of Conegliano, San Pietro di Feletto (Treviso), Buso dei Zambon Cave (6080 V/ TV), 190 m a.s.l., coll. E. Piva, 13.4.2009; adult female, Veneto, the Monti Berici Mts, Arcugnano (Vicenza), in the mesovoid shallow substratum habitat (cf. Juberthie 2000), in a grove east of the Moreieta Restaurant (out of the limestone zone), 335 m a.s.l., coll. E. Piva, 3.5.2009, all in collection of M. Zacharda.

Diagnosis

Naso short. Cheliceral digits smooth along masticatory surface; prebasal laterodorsal fissure on fixed digit positioned at level of insertion of proximal cheliceral seta; proximal cheliceral seta inserted distad of articulation of cheliceral digits; tip of proximal seta not reaching insertion of distal seta. Palpal tarsus shorter than femorogenu, with ten pubescent setae. Solenidion on palpal tarsus recumbent, lying in superficial depression. Coxae I, II, III, IV with 3-1-6-3 finely pubescent setae, respectively; exceptionally five setae on coxa III asymmetrically. Rhagidial organ I comprised of four strikingly long oblique separate rhagidial solenidia (ω) that are much longer than diameter of tarsus at site of their insertion; stellate famulus (ε) subtending second proximal rhagidial solenidion antiaxially; rhagidial organ II comprised of three rhagidial solenidia lying in tandem, two proximal in confluent depressions and one distal in separate depression; small spiniform famulus (ε) subtending proximal rhagidial solenidion. Tibia I with one long recumbent dorsal mediodistal solenidion (Φ) lying in depression and resembling rhagidial solenidion.

Affinities

Traegaardhia cavernarum n. sp. differs from the majority of other known Traegaardhia -species in the recumbent solenidia on tibia I and palpal tarsus. In the other known Traegaardhia -species the proximal solenidia on tibiae I and palpal tarsus are spiniform and erect, except in T. paralleloseta ( Zacharda 1985: 76.) in which these solenidia are also recumbent, but the solenidion on the palpal tarsus is spiniform, erect ( Fig. 36E,G,H,I).

Etymology The epithet cavernarum reflects the subterranean habitats where the species occurs. Feminine gender.

Description

Adult female (four examined). Length of idiosoma 912(880–992) µm. Ratio of leg I length to idiosomal length 1.63(1.35–1.84).

Gnathosoma . Subcapitulum broadly oval, subtriangular ( Fig. 18F); ratio of length to breadth 1.22(1.13– 1.34); distal hypostomal lips with spiniform internal and serrate external malar processes; adoral setae nude, overlapping apex of subcapitulum; proximal subcapitular setae pubescent, external pair slightly longer than internal pair. Dorsal surface of chelicera with saddle-shaped depression at level of bases of digits ( Fig. 18A,B); cheliceral digits long, slender; fixed digit terminates in two cusps, smooth along masticatory surface and with distinct prebasal laterodorsal fissure located at level of insertion of proximal cheliceral seta; movable digit smooth along masticatory surface. Chelicera with two setae; proximal seta inserted distad of articulation of cheliceral digits; tip of proximal seta not reaching insertion of distal seta; tip of distal seta distinctly overlaps apex of fixed digit. Length of chelicera 259(244–274) µm, dorsoventral width 101(89–112) µm, length of movable digit 108(102–115) µm, length of proximal and distal cheliceral setae 25(20–30) and 48(43–53) µm, respectively, distance between their insertions 29(23–36) µm. Ratios: cheliceral length to dorsoventral width 2.56(2.44–2.81), length of movable digit to length of chelicera 0.42(0.41–0.43), length of movable digit to dorsoventral width of chelicera 1.06(1.0–1.18). Palpal tarsus shorter than femorogenu; ratio of length to dorsoventral width of tarsus 2.87(2.63–2.83). Solenidion on palpal tarsus recumbent, lying in depression ( Fig. 18G). Length of palpal trochanter, femorogenu, tibia and tarsus 44(43–49), 134(119–145), 58(53–66) and 109(102–115) µm, respectively. Number of setae and solenidia (in brackets) on palpal trochanter, femorogenu, tibia and tarsus 0-2-3-10(1), respectively.

Prodorsum. Naso short, with pair of internal vertical setae v 1 ( Fig. 17A). Bothridial setae sc 1 filiform, finely pubescent, reaching to insertions of opisthosomal setae c 1. Length of setae: v 1 62(59–66), v 2 54(46–63), sc 1 142(135–148), sc 2 145(138–152) µm.

Opisthosomal dorsum and anal region. Cupules ia positioned proximad of insertions of setae c 2, and about midway between insertions of setae c 1 and d 1; im lateral and about at level of insertions of e 1; ip lateral and about at level of insertions of setae f 1; ih positioned ventrolaterally in anal region, laterad of insertions of adanal setae ad 1 ( Fig. 17A,B). Short setae c 1, d 1, e 1 reach about half of distance to insertions of successive setae; seta f 1 overlaps insertion of h 1. Length of setae: c 1 58(40–66), c 2 143(129–158), d 1 52(40–59), e 1 52 (40– 59), f 1 73(59–79), f 2 40(36–46), h 1 124(115–132), h 2 56(46–63), ps 1 103(99–105), ps 2 58(49–66), ps 3 54(49– 59), ad 1 55(48–60) µm.

Podosoma. Coxae I, II, III, IV with 3-1-6-3 finely pubescent setae, respectively; exceptionally five setae on coxa III asymmetrically.

Genital region. Genital valves each with five or six finely pubescent genital setae (g) of similar length, about 27(20–30) µm, arranged evenly along medial edge of valve ( Fig. 17B). Five pairs of aggenital setae (ag) of similar length, about 49(46–53) µm. Length of genital valves 122(102–138) µm.

Legs. Leg I 1484 (1344–1648) µm long, about 1.63(1.35–1.84) as long as idiosoma. Empodia of all legs setulose, broadly oval in dorsoventral view, slightly overlapping claws; claws each with small tubercle ventrobasally. Number of setae and solenidia (solenidia and famulus (ε) bracketed), respectively, on legs I-II-III- IV (Figs 19,20): trochanters 1-1-2-2, basifemora + telofemora 6+5-5+5-4+4-3+4, genua 12(1)-9(1)-7(1)-6, tibiae 11(2)-7(2)-7(2)-6(1), tarsi 19(4+ε)-16(3+ε)-14-14. Genua I and II each with one erect spiniform distoventral solenidion (σ); genu III with one small dorsoproximal spiniform solenidion. Tibia I with one recumbent dorsal mediodistal solenidion (Φ) resembling slender rhagidial solenidion ( Fig. 19C) (homologous with erect spiniform solenidion), and one small dorsodistal rhagidial solenidion; tibia II with one erect spiniform dorsoproximal solenidion, and one dorsodistal lanceolate solenidion recessed in deep pit with broadly open surface pore ( Fig. 19D); tibia III with two erect spiniform dorsoproximal solenidia arranged in tandem; tibia IV with one erect spiniform laterodorsal proximal solenidion. Tarsus I slender, its tip slightly tapers in lateral view, ratio length to width 6.31(5.71–6.66), with four strikingly long oblique separate rhagidial solenidia (ω) dorsodistally; stellate famulus (ε) subtending second proximal rhagidial solenidion antiaxially ( Fig. 18D); tarsus II with three rhagidial solenidia lying in tandem, two proximal of them in confluent and one distal in separate depressions; small spiniform famulus (ε) subtending proximal rhagidial solenidion ( Fig. 18E).

Adult male (one examined). Length of idiosoma 912 µm. Ratio of leg I length to idiosomal length 1.62. Sperm sac club-shaped, showing through tegument. Otherwise as in females.

Remarks

Traegaardhia cavernarum is the most common cave rhagidiid mite in northeastern Italian Prealps. Aside from caves it was also recorded in the mesovoid shallow substratum ( Juberthie 2000; Culver & Pipan 2009). It is a troglomorphic troglobiont.