Forsteropsalis bona, 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 : 39-41

Taxon classification Animalia Opiliones Neopilionidae

Forsteropsalis bona sp. n. Figure 1

Holotype male.

WO. Lucky Strike Cave, Te Kuiti, on wall near entrance, 14 Feb 1959, K. A. J. Wise (MONZ).

Paratypes.

WO. 2 males, Waitomo Valley, in stream crevice outside cave entrance (shady), specimens intertwined and sluggish, 30 Mar 1959, L. G. Watson (MONZ); 1 male, Weir Cave, Stubbs Farm, Waitomo, ca. 2 m from cave entrance within a 15 cm radius of Arachnocampa luminosa larvae, 23 Aug 2010, A. Probert (NZAC).

Etymology.

From the Latin bonus, good, in contrast to the related Forsteropsalis fabulosa .

Male (n=4).

Total body length 4.8-6.6; prosoma length 2.5-2.8, width 4.0-4.2. Prosoma (including ocularium) unarmed (Fig. 1A); ground colour in alcohol orange-brown with longitudinal yellow stripes on either side of ocularium (live coloration very dark brown [almost black] with orange-yellow stripes; appendages also black). Ozopores elongate, with small flanking lobes. Opisthosoma grey-yellow. Mouthparts cream-coloured; medial side of pedipalpal coxa with dense array of sharp denticles; cervix unarmed. Coxae yellow. Chelicerae (Fig. 1B): Segment I length 6.2-8.4; segment II 9.4-10.4. Elongate; segment I orange with lighter yellow patch at distal end, segment II dark orange-brown. Segment I denticulate, with denticles concentrated along dorsal, proventral and retroventral margins. Segment II massively inflated, evenly denticulate. Cheliceral fingers elongate, widely bowed apart; setae present on distal half of mobile finger. Pedipalps: Femur length 5.4-5.7; patella 2.2-2.4; tibia 2.8-3.1; tarsus 5.8-6.5. Distinctly elongate, yellow. Femur dorsally denticulate on proximal two-thirds; remainder of pedipalp unarmed. Setae sparse except for small concentration at prodistal end of patella; microtrichia present on tarsus and distal half of tibia; prodorsal end of patella with distinct protrusion but without definite finger-like apophysis (Fig. 1C). Tarsal claw without ventral tooth-row. Legs: Legs I femur length 8.6-9.9, patella 1.9-2.5, tibia 8.3-9.8; leg II femur 14.3-17.2, patella 2.2-2.8, tibia 14.4-17.8; leg III femur 7.5-8.7, patella 1.7-2.3, tibia 5.3-8.2; leg IV femur 8.5-10.7, patella 1.8-2.7, tibia 10.2-10.8. Femora sparsely denticulate, particularly in proximal half; remainder of legs unarmed. Distitarsus I with strong ventral tooth at distal end of each of first five or six pseudosegments (Fig. 1D). Tibia II with nine to fifteen pseudosegments; tibia IV with two pseudosegments. Penis (Fig. 1 E–F): Shaft subquadrate; tendon long. Bristle groups relatively long, posterior bristle group with longest bristles reaching dorsal margin in lateral view. Glans short, subtriangular in ventral view, narrowing rapidly in lateral view.

Comments.

Females of this species are currently unknown. Forsteropsalis bona can be distinguished from most other Forsteropsalis species by its unarmed prosoma and enormous, sub-globose cheliceral segment II with widely bowed cheliceral fingers ( Taylor 2011). In these features it strongly resembles Forsteropsalis fabulosa , and would key out to either Forsteropsalis fabulosa or Forsteropsalis tumida in the key to Forsteropsalis species provided by Taylor (2011). These two species are synonymised below. Forsteropsalis bona can be distinguished from Forsteropsalis fabulosa by the form of the pedipalpal patella: Forsteropsalis fabulosa has a distinct finger-like prodistal apophysis on the patella ( Phillipps and Grimmett 1932: Fig. C p. 732), while the patellar apophysis is almost absent in Forsteropsalis bona (Fig. 1C). Forsteropsalis fabulosa also has denticles both dorsally and ventrally on the pedipalpal femur, while Forsteropsalis bona has denticles dorsally only.

An interesting feature of Forsteropsalis bona is the presence of a strong ventrodistal tooth on the end of each of the proximal pseudosegments of the distitarsus. This tooth sits between the two spinose setae generally present on each tarsal pseudosegment in all Enantiobuninae (Fig. 1D). Such a feature has not previously been recorded for this subfamily, though it is also present in Forsteropsalis fabulosa (specimens from MONZ, details given in Taylor 2011). This may represent a distinct synapomorphy of these two species.

The glans of both Forsteropsalis fabulosa ( Taylor 2011) and Forsteropsalis bona is relatively short compared to other Forsteropsalis species, and converges in shape on that of the Australian genus Megalopsalis ( Taylor 2011, 2013). Nevertheless, the remaining features of these two species support a direct relationship with other New Zealand species of Pantopsalis and Forsteropsalis , and with Forsteropsalis in particular. These features include dorsal papillae on the glans ( Taylor 2011), setae on the mobile finger of the chelicera (absent in Megalopsalis except Megalopsalis caeruleomontium ; Taylor 2011, 2013), and an array of denticles on the medial side of the pedipalpal coxa (Fig. 3A; Taylor 2011).