Traegaardhia cavernicola 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 : 13-17

Traegaardhia cavernicola Zacharda , n. sp. ( Figs 6–9)

Material examined

HOLOTYPE: adult female, Italy, Friuli, the Stubai Alps, Monte Cavallo mountain range, Barcis (Pordenone), Grotte Vecchia Diga Cave (327 Fr/ PN), 484 m a.s.l., coll. E. Piva, 5.3.1995, deposited in the Museum of Biological Diversity , Ohio State University, Type No. OSAL0007407; paratypes (deposited with the holotype): two adult females, same data as holotype, coll. E. Piva, 27.11.1994, OSAL0007408 and OSAL0007409.

Diagnosis

Cheliceral digits smooth along masticatory surface, prebasal lateral fissure on fixed digit located at level of insertion of proximal cheliceral seta; proximal cheliceral seta inserted just above articulation of movable digit; tip of proximal seta not reaching insertion of distal seta. Palpal tarsus same length as femorogenu, with ten pubescent setae and one spiniform solenidion. Coxae I, II, III, IV with 3-1-5-3 finely pubescent setae, respectively. Rhagidial organ I comprised of four strikingly long, slender, serpentine rhagidial solenidia (ω) lying obliquely in separate depressions; stellate famulus (ε) inserted between second and third proximal rhagidial solenidia antiaxially; rhagidial organ II comprised of three long rhagidial solenidia lying in slightly oblique separate depressions, and small spiniform famulus (ε) subtending proximal rhagidial solenidion. Spiniform solenidion (Φ) on tibia I lateroventral, mediodistal. Spiniform solenidion (σ) on genu II ventral, proximal, on genu III lateroventral, proximal.

Affinities

Traegaardhia cavernicola n. sp. is very similar to T. vicenzaensis Zacharda, 1994 from which it can be distinguished by the following characters: (1) The length of body 860–930 µm; in T. vicenzaensis it is approx. 1280–1300 µm. (2) The stellate famulus (ε) in rhagidial organ I is positioned between the second and third proximal rhagidial solenidion antiaxially; in T. vicenzaensis it subtends the second proximal rhagidial solenidion. (3) The rhagidial solenidia in rhagidial organ II are inserted in separate, slightly oblique depressions; in T. vicenzaensis they are inserted in tandem in confluent depressions. (4) The spiniform solenidion on tibia I is lateroventral, mediodistal; in T. vicenzaensis it is ventral, mediodistal. (5) The spiniform solenidion on genu II is ventral, proximal; in T. vicenzaensis it is distoventral.

Etymology The epithet cavernicola reflects the cave habitat where this species was discovered. Feminine gender.

Description

Adult female (three examined). Length of idiosoma 890(864–928) µm. Ratio of leg I length to idiosomal length 2.09(2.05–2.12).

Gnathosoma . Subcapitulum slenderly oval, subtriangular ( Fig. 7F); ratio of length to breadth 1.58(1.56– 1.60); distal hypostomal lips with spiniform internal and serrate external malar processes; adoral setae nude, long and overlapping apex of subcapitulum; proximal subcapitular setae pubescent, external and internal pair about the same length. Dorsal surface of chelicera with shallow saddle-shaped depression located slightly distad of articulation of digits ( Fig. 7A,B); cheliceral digits long, slender; dorsal surface of fixed digit with distinct short narrow rim above insertion of distal cheliceral seta; fixed digit terminates in two cusps, smooth along masticatory surface and with prebasal lateral fissure located at level of insertion of proximal cheliceral seta; movable digit smooth along masticatory surface. Chelicerae with two setae, proximal seta inserted just above articulation of movable digit; tip of proximal seta not reaching insertion of distal seta; tip of distal seta not reaching apex of fixed digit. Length of chelicera 258(247–264) µm, dorsoventral width 79 µm, length of movable digit 90(86–92) µm, length of proximal and distal cheliceral setae 28(26–30) and 42(39–46) µm, respectively, distance between their insertions 36 µm. Ratios: cheliceral length to dorsoventral width 3.26(3.12–3.33), length of movable digit to length of chelicera 0.34(0.33–0.35), length of movable digit to dorsoventral width of chelicera 1.13(1.08–1.16). Palpal tarsus ( Fig. 7E) the same length as femorogenu; ratio of length to width of tarsus 4.93(4.70–5.10). Length of palpal trochanter, femorogenu, tibia and tarsus 53(49– 56), 154(142–165), 87(82–92) and 163(155–168) µm, respectively. Number of setae and solenidia (in brackets) on palpal trochanter, femorogenu, tibia and tarsus 0-2-3-10(1), respectively; tarsal solenidion spiniform, erect.

Prodorsum. Naso well-developed, with pair of internal vertical setae v 1 ( Fig. 6A). Bothridial setae sc 1 filiform, finely pubescent, long, overlapping insertions of opisthosomal setae c 1. Length of setae: v 1 73, v 2 81(73– 89), sc 1 161(158–165), sc 2 157(155–158) µm.

Opisthosomal dorsum and anal region. Cupules ia positioned laterally between setae c 1 and d 1; im lateral and just anterior to setae e 1; ip just distad of insertion of f 2; ih positioned ventrolaterally in anal region, laterodistad of insertions of adanal setae ad 1 ( Fig. 6A,B). Setae c 1, d 1, e 1 slightly shorter than distances between rows of setae; setae f 1 overlapping insertions of h 1. Length of setae: c 1 97(96–99), c 2 126(115–142), d 1 85(82–89), e 1 85(82–89), f 1 105(102–109), f 2 80(79–82), h 1 155, h 2 86(82–92), ps 1 122(119–125), ps 2 88(86–92), ps 3 56(53– 59), ad 1 80(75–90) µm.

Podosoma. Coxae I, II, III, IV with 3-1-5-3 finely pubescent setae, respectively.

Genital region. Genital valves each with five finely pubescent genital setae (g) of similar length, about 39(26–53) µm, arranged evenly along medial edge of valve; sometimes five and six setae on each valve asymmetrically, ( Fig. 6B). Five pairs of aggenital setae (ag) of similar length, about 70(63–82) µm. Length of genital valves 137(132–148) µm.

Legs. Leg I 1867 (1824–1904) µm long, about 2.09(2.05–2.12) as long as idiosoma. Empodia of all legs setulose, slightly longer than claws; claws each with small clawlet (basal spur) ventrobasally. Number of setae and solenidia (solenidia and famulus (ε) bracketed), respectively, on legs I-II-III-IV (Figs. 8,9): trochanters 1- 1-2-2, basifemora + telofemora 5+5-6+5-4+4-3+4, genua 12(1)-9(1)-7(1)-6, tibiae 12(2)-7(2)-7(2)-6(1), tarsi 20(4+ε)+16(3+ε)−14-14. Genu I with one erect spiniform distoventral solenidion (σ); genu II with one erect spiniform proximoventral solenidion; genu III with one erect spiniform lateroventral proximal solenidion. Tibia I with one erect spiniform lateroventral mediodistal solenidion (Φ), and one dorsodistal rhagidial solenidion; tibia II with one spiniform erect dorsoproximal solenidion, and one large lanceolate dorsodistal solenidion recessed in deep pit with large elongated, broadly open surface pore ( Fig. 7G); tibia III with two adjacent erect spiniform dorsoproximal solenidia; tibia IV with one erect spiniform laterodorsal proximal solenidion. Tarsus I slender, its tip slightly tapers in lateral view, ratio length to width 8(7.3–8.3), with four strikingly long, slender serpentine rhagidial solenidia (ω) lying obliquely in separate depressions dorsodistally; stellate famulus (ε) between second and third proximal rhagidial solenidion antiaxially ( Fig. 7C); tarsus II with three rhagidial solenidia lying in separate slightly oblique depressions, and small spiniform famulus (ε) subtending proximal rhagidial solenidion ( Fig. 7D).

Remarks

The elongated slender cheliceral digits, and particularly the strikingly elongated and attenuated rhagidial solenidia in the rhagidial organs I and II together with the enlarged dorsodistal lanceolate solenidion lying in pit with the broadly open surface pore on the tibia II as well as the long palpal tarsus and the very long leg setae are all troglomorphisms associated with adaptations to life in the subterranean environment. Traegaardhia cavernicola n. sp. may be considered a troglobiont.