Trilacuna qarzi Malek Hosseini & Grismado

Hosseini, Mohammad-Javad Malek, Grismado, Cristian J., Sadeghi, Saber & Bakhshi, Yaser, 2015, Description of the first cave dwelling species of the spider genus Trilacuna Tong & Li from Iran (Araneae: Oonopidae), Zootaxa 3972 (4), pp. 549-561 : 552-554

Trilacuna qarzi Malek Hosseini & Grismado , sp. nov.

( Figures 2−8 )

Types. Male holotype, Iran: Kohgiluyeh and Boyer-Ahmad Province: Gachsaran County: Gakal Cave, 1100m, 30.31222°, 51.15778°, June 24, 2013, Mohammad-Javad Malek Hosseini, Yaser Bakhshi & Saber Sadeghi coll. (ZM CBSU Sp-Ar_001, PBI_OON 42521). Paratypes, same data: 2 ♂, 3♀ (ZM CBSU Sp-Ar_002, PBI_OON 42523), 1♀ (MACN-Ar 31941, PBI_OON 42519), 1♂ (MACN-Ar 31943, PBI_OON 42520), 1♂ (MACN-Ar 31944, PBI_OON 42544), 1♀ (MACN-Ar 31939, PBI_OON 42545), 1♀ (MACN-Ar 31942, PBI_OON 42546).

Etymology. The specific epithet is a Persian word that means “cave dweller”, referring to the habitat where this species was found.

Diagnosis. Trilacuna qarzi is easily distinguishable from the other known species of the genus by its troglomorphic characters: absence of eyes, pale integuments and relatively long legs ( Figs. 1 , 3 ). The male palp is similar to those of T. bangla and T. aenobarba , but has the cymbium partially fused to the bulb, and its embolic division shows a more complex set of filiform structures ( Figs. 7 , 8 B).

Description. Male (holotype). Total length 1.70. CEPHALOTHORAX: Carapace pale orange, without any pattern, broadly oval in dorsal view, pars cephalica slightly elevated in lateral view, anteriorly narrowed to between 0.5 and 0.75 times its maximum width, with rounded posterolateral corners, surface of elevated portion of pars cephalica with sparse granulation, sides strongly granulate, fovea absent; lateral margin straight, smooth, without denticles; non-marginal pars cephalica setae light, needle-like, the most lateral setae seem to be distributed in an Ushaped row, and pointing to the center; the medial setae appear as scattered.; pars thoracica setae light, needle-like. Clypeus margin unmodified, curved downwards in front view, vertical in lateral view, median projection absent; setae light, needle-like. Chilum absent. Eyes absent. Sternum longer than wide, pale orange, uniform, not fused to carapace, without radial furrows between coxae I–II, II–III, III–IV, surface finely reticulate, without pits, microsculpture covering entire surface, anterior margin unmodified, posterior margin not extending posteriorly of coxae IV, distance between coxae approximately equal, extensions of pre-coxal triangles present, lateral margins unmodified, without posterior hump; setae sparse, light, needle-like, evenly scattered, originating from surface, without hair tufts. Mouthparts: Chelicerae, endites and labium pale orange. Chelicerae straight, anterior face unmodified; fangs without tooth-like projections, directed medially, shape normal, without prominent basal process, tip unmodified; setae light, needle-like, evenly scattered; paturon inner margin with pairs of enlarged setae, distal region abruptly narrowed. Labium triangular, fused to sternum, anterior margin deeply incised, same as sternum in sclerotization; with 3–5 setae on anterior margin, subdistal portion with unmodified setae. Endites distally not excavated, serrula present in single row, posteromedian part unmodified, same as sternum in sclerotization. ABDOMEN: ovoid, rounded posteriorly; dorsum soft portions pale white, without color pattern. Book lung covers large, elliptical, without setae, anterolateral edge unmodified. Posterior spiracles connected by a shallow groove. Pedicel tube medium-sized, ribbed, scuto-pedicel region unmodified, scutum not extending far dorsal of pedicel. Dorsal scutum strongly sclerotized, pale orange, without color pattern, covering full length of abdomen, more than 1/2 to most of abdomen width, not fused to epigastric scutum, with smooth surface. Epigastric scutum strongly sclerotized, surrounding pedicel, not protruding, small lateral sclerites absent. Postepigastric scutum strongly sclerotized, pale orange, long, semicircular, covering about 3/4 of abdominal length, fused to epigastric scutum. Spinneret scutum present, incomplete ring. All abdominal setae light, needle-like. Colulus absent. LEGS: pale orange, without color pattern; femur IV not thickened, same size as femora I–III, patella plus tibia I near as long as carapace, tibia I unmodified. Leg spination (only surfaces bearing spines listed, all spines longer than segment width): leg I: femora: PV0-0-1-0; tibiae: V2-2 -2-2-0; metatarsi: V2-2 -0, leg II: tibiae: V2-2 -2- 2-0; metatarsi: V2-2 -0. Tarsi I to IV superior claws tooth not examined in detail. Tarsi I to IV without inferior claw. Trichobothria: only examined the palpal tibial trichobothria ( Fig. 6 G): proximal plate not well differentiated and not overhanging the distal plate, more or less at the same level, both plates with similar sculpture as in the surrounding cuticle; alveolus narrowed at the proximal margin. GENITALIA: Epigastric region with sperm pore small, circular, situated at level of anterior spiracles, unmodified. Palp normal size, not strongly sclerotized, right and left palps symmetrical, proximal segments pale orange; embolus: only the tip visible (by SEM, Fig. 7 H), distally curved to the prolateral side, lying in the anteroventral hairy process; trochanter normal size, unmodified; femur enlarged, two or more times as long as trochanter, without posteriorly rounded lateral dilation, attaching to patella basally; patella shorter than femur, not enlarged,; cymbium pale orange, ovoid in dorsal view, not extending beyond distal tip of bulb, plumose setae and stout setae absent, abruptly narrowed in the distal third; completely fused with the bulb in the prolateral side ( Fig. 7 C), seam visible in the retrolateral side, but tip not fused, free ( Figs. 7 A, B); tarsal organ nearly rounded, with two sensilla visible ( Fig. 6 H); bulb pale orange, 1 to 1.5 times as long as cymbium, tapering apically, internally, in clove oil preparation, are clearly visible the internal glandular tube typical of the Dysderoides complex ( Fig. 8 B). Its origin is approximately the center of the bulb, continues tortuously to the dorsal and, near the distal third is bent anteroventrally, describing a straight trajectory to the distal part. Embolic division.with a complicated set of "hairy" projections: three bunches of setiform projections around the embolus, distal to a relatively sclerotized subterminal area. The dorsal one have projections with arrow-shaped tips, disposed as a fan in many rows ( Figs. 7 D −F); the anteroventral bunch have projections with rounded tips and apparently annulated surface ( Fig. 7 D); on the retrolateral side, there are an additional flange with a oblique furrow, and with a few filiform structures directed backwards ( Fig. 7 D); on the prolateral side there is a V-shaped keel defining an anterior concavity, and with two different types of setiform processes: the most distal are larger, stout, disposed at the same plane as the anteroventral, annulated setae; the more proximal are thinner, and are arranged on the margin of the projection ( Fig. 7 G).

Female (paratype, PBI_OON 42545). Total length 2.10. As in male except as noted. CEPHALOTHORAX: Carapace with a more sparse granulation; posterior part elevated, with a nearly peak-like profile in lateral view ( Fig. 5 B); non-marginal pars cephalica setae present in u-shaped row, with some sparse setae in the anteromedian part. Palp: claws absent, spines absent, tarsus unmodified. ABDOMEN: Dorsal scutum covering more than 3/4 of abdomen. Postepigastric scutum long, almost rectangular, covering about 1/2 of abdominal length ( Figs. 4 B, H). LEGS: Tarsi I to IV superior claws ( Figs. 6 A −D): inner faces with the row of teeth displaced to the distal half, eight on leg I, ten on leg II, four on leg III, and only one, very enlarged, on leg IV. Trichobothria not examined. Tarsal organ nearly round, on leg I (and presumably also leg II) with three sensilla visible; on leg III (and presumably on the leg IV and palp) with two ( Figs. 6 E −F). Epigastrium: two procurved, nearly parallel plates before the genital opening, the anterior one with a median notch on the posterior margin ( Figs. 4 H, 8A); lateral apodemes visible through ventral cuticle. GENITALIA: anterior sclerite T-shaped, with the lateral tips of the transverse bar connected with the lateral apodemes through muscles. Posterior receptacle small, relatively elongated ( Fig. 8 A). OTHER MATERIAL EXAMINED: Same data as the types, 12 ♀ (ZM CBSU, PBI_OON 42524); same locality and collectors, May 18 2012, 2 ♀ (ZM CBSU, PBI_OON 42525); October. 2, 2012, 4♀ (ZM CBSU, PBI_OON 42526)

Habitat. Gakal Cave ( Fig. 1 ) is situated in a mountainous region near the Sartip Abad village, 40 km east of Gachsaran, in the province of Kohgiluyeh and Boyer-Ahmad, southwestern Iran. The cave has a large central hall; water (pH: 7.15) accumulate in small pools in different parts, temperature is around 23°C, and relative humidity is very high (90–99%). The cave floor is covered with a layer of bat guano. The specimens were collected by aspirator and small brush, some of them were separated from bat guano using a Berlese funnel at the laboratory. Some specimens were jumping and walking on guano.

Figures

FIGURE 2. Trilacuna qarzi sp. n. male holotype. A, habitus, dorsal view; B, same, ventral view; C, same, lateral view; D, cephalothorax, dorsal view; E, same, ventral view; F, lateral view.

FIGURE 3. Trilacuna qarzi sp. n. male holotype. A, habitus, anterior view; B, abdomen, ventral view; C, left palp, prolateral view; D, same, ventral view; E, same, retrolateral view; F, same, dorsal view.

FIGURE 4. Trilacuna qarzi sp. n. female paratype (PBI _ OON 42545). A, habitus, dorsal view; B, same, ventral view; C, same, lateral view; D, cephalothorax, dorsal view; E, same, ventral view; F, lateral view; G, anterior view; H, epigastric region, ventral view.

FIGURE 5. Trilacuna qarzi sp. n. female paratype (PBI _ OON 42546). A, cephalothorax and legs, lateral view; B, carapace, lateral view, close up; C, ocular area, lateral view; D, sternum, ventral view; E, mouthparts, ventral view; F, right leg I, prolateral view. Arrow = incision of the labium.

FIGURE 6. Trilacuna qarzi sp. n. A − E female paratype (PBI _ OON 42546); G − H male paratype (PBI _ OON 42520). A − D, tarsal claws on right legs. A, leg I dorsal view; B, leg II, oblique lateral view; C, leg III, dorsal view; D, leg IV, dorsal view; E, tarsal organ of leg I; F, same, leg III; G, trichobothrium of left palpal tibia; H, tarsal organ on cymbium.

FIGURE 7. Trilacuna qarzi sp. n., male paratype (PBI _ OON 42520), left palp. A, retrolateral view; B, same, dorsal view; C, copulatory bulb, prolateral view; D, detail of the embolic division, retrolateral view; E, detail of the arrow-shaped setiform processes; F, detail of embolic division, dorsal view; G, same, prolateral view; H, embolus opening.

FIGURE 8. Trilacuna qarzi sp. n., genitalia, cleared preparations. A, female paratype (PBI _ OON 42546), B, male holotype. A, internal genitalia, dorsal view (ap = apodeme, as = anterior sclerite, pr = posterior receptacle); B, left palp, retrolateral view (gt = glandular tube).

FIGURE 1. A, map of Iran, showing the location of Kohgiluyeh and Boyer-Ahmad Province (in orange). B, Kohgiluyeh and Boyer-Ahmad Province, showing the location of Gakal Cave. C, Gakal Cave, external view of the entrance. D, aspect of the central hall of the cave.