Forsteropsalis photophaga, Taylor, Christopher K. & Probert, Anna, 2014

Taylor, Christopher K. & Probert, Anna, 2014, Two new species of harvestmen (Opiliones, Eupnoi, Neopilionidae) from Waitomo, New Zealand, ZooKeys 434, pp. 37-45 : 41-43

Taxon classification Animalia Opiliones Neopilionidae

Forsteropsalis photophaga sp. n. Figure 2

Holotype male.

WO. Waitomo, Gardners Gut Cave System, 200 yards from Zweihöllen entrance, 25 June 1977, W. L. Blundell (MONZ).

Paratypes.

WO. 1 male, Giants Cavern, Hollow Hill Cave, Te Kuiti, in 'Crows Nest’, 60-70 ft high, 12 January 1958, coll. R. W. Taylor (MONZ); 1 male, Aussie Cave, Taumatamaire Rd, Waitomo County, 50 ft, 16 May 1966, K. A. J. Wise (MONZ); 2 males, Stubbs Farm, Waitomo, on rocky cave substrate, February 2013, G. Holwell et al. (NZAC); 2 males, Mangapohue Cave, Stubbs Farm, Waitomo, on rocky cave substrate, 21 Oct 2013, A. Probert & D. Townsend (NZAC).

Etymology.

From the Greek phos, light, and phagein, to eat, in reference to this species’ predation of the glow-worm Arachnocampa luminosa .

Male (n=7).

Total body length 3.5-6.1; prosoma length 1.9-2.1, width 2.5-3.9. Prosoma (including ocularium) unarmed except for few black setae (Fig. 2A); ground colour orange-brown with longitudinal yellow stripes on either side of ocularium (live colouration light to mid-brown with pale yellow stripes). Ozopores elongate, with small flanking lobes. Opisthosoma grey-brown. Mouthparts cream-coloured; medial side of pedipalpal coxa with array of sharp denticles; cervix with single pair of denticles laterally. Coxa I orange; remaining coxae and venter of opisthosoma yellow. Chelicerae (Fig. 2B, D): Segment I length 3.4-6.5, segment II 4.9-9.1. Elongate; orange except for lighter yellow patch at distal end of first segment. First segment dorsally with scattered denticles, becoming more elongate retrolaterally, ventrally with longitudinal prolateral and retrolateral rows of elongate denticles and some scattered median denticles proximally. Second segment mildly to notably inflated, sub-conical, evenly denticulate with longitudinal rows of more elongate denticles dorsally and retrolaterally. Cheliceral fingers elongate, slightly bowed apart; setae present along central third of mobile finger. Pedipalps: Femur length 4.6-6.5, patella 2.8-3.2, tibia 2.2-2.8, tarsus 4.8-5.7. Distinctly elongate; yellow. Median side of coxa with array of sharp denticles. Femur with few denticles dorsally in proximal half; remainder of pedipalp unarmed. Patella, tibia and proximal half of tarsus densely covered with plumose setae; microtrichia present over entirety of patella, tibia and tarsus; patella with small, rounded, prodistal apophysis (Fig. 2C). Tarsal claw without ventral tooth-row. Legs: Leg I femur length 8.1-11.0, patella 1.9-2.2, tibia 8.4-10.7; leg II femur 14.0-17.7, patella 1.9-2.5, tibia 16.0-19.0; leg III femur 7.1-9.4, patella 1.6-1.9, tibia 7.6-9.8; leg IV femur 9.0-12.2, patella 1.8-2.2, tibia 10.3-12.4. Yellow. Proximal half of femur I with few scattered dorsal denticles; remainder of legs unarmed. Tibia II with 12 pseudosegments; tibia IV with three pseudosegments. Penis (Fig. 2 E–F): Shaft subquadrate; tendon long. Bristle groups relatively long, posterior bristle group with longest bristles reaching dorsal margin in lateral view. Glans relatively long, subrectangular in ventral view, remaining relatively deep to distal end but with dorsodistal end rounded.

Comments.

Females of this species are currently unknown. The holotype of Forsteropsalis photophaga when first examined had a parasitic mite attached to the opisthosoma (Fig. 2A). This mite is a representative of the Microtrombidiidae , a family that has not previously been recorded as parasitic on Opiliones ; a more detailed description is currently being prepared by C. Taylor.

The genera Pantopsalis and Forsteropsalis have hitherto been regarded as well distinguished by the morphology of the cheliceral fingers (crescent-shaped in Pantopsalis vs bowed in Forsteropsalis ), pedipalpal patellar apophysis (hypersetose and rounded in Pantopsalis , sparsely setose and triangular in Forsteropsalis ) and penile bristle groups (shorter in Pantopsalis than in Forsteropsalis ) ( Taylor 2004, 2011). The current species blurs this distinction: in its hypersetose and rounded pedipalpal apophysis it resembles Pantopsalis , but its elongate cheliceral fingers and penile bristle groups are more characteristic of Forsteropsalis . It also possesses an array of denticles on the medial side of the pedipalpal coxa as found in Forsteropsalis species (Fig. 3A; Taylor 2011). We therefore assign it to the latter genus herein. A hypersetose, rounded patella is also present in the female of Forsteropsalis grimmetti , though the male of that species possesses a more typical Forsteropsalis -type patella ( Taylor 2011). It is possible that the hypersetose patella is in fact a symplesiomorphy of Pantopsalis and Forsteropsalis , with Forsteropsalis photophaga being a basal member of the latter genus.

Forsteropsalis photophaga can be readily distinguished from all other Neopilionidae in New Zealand by the hypertrophied denticle rows on the second cheliceral segment. The only other neopilionid with comparable chelicerae is the major male of the Tasmanian species Megalopsalis nigricans ( Hickman 1957). This, however, is a much smaller species, with very different genital morphology and with small ozopores unlike those of any Forsteropsalis species ( Hickman 1957, Taylor 2013).