Indohya finitima Harvey & Burger, 2023

Harvey, Mark S., Burger, Mieke A. A., Abrams, Kym M., Finston, Terrie L., Huey, Joel A. & Perina, Giulia, 2023, The systematics of the pseudoscorpion genus Indohya (Pseudoscorpiones: Hyidae) in Australia, Zootaxa 5342 (1), pp. 1-119 : 100-101

Indohya finitima Harvey & Burger , n. sp.

( Figs. 6B , 56 , 57 )

urn:lsid:zoobank.org:act:7BB10C00-6DFD-4EF1-9A2B-182BF477B164

Material examined. Holotype adult. AUSTRALIA: Western Australia: Irvine Island , bore ID27, 16°05′37.75″S, 123°33′18.66″E, 1 June–1 August 2011, troglofauna trap, 10 m depth, J. Alexander, S. Werner ( WAM T120197 ).

Diagnosis. Indohya finitima belongs to a group of Indohya species that have 12 setae on the carapace and no eyes. It differs from I. anastomosa , I. aquila and I. humphreysi by the presence of 4 setae on tergite I (only 2 setae in I. anastomosa , I. aquila and I. humphreysi ). It differs from all of the others except I. arnoldstrongi by the rounded distal teeth of the fixed chelal finger (at least 2 distal teeth pointed in I. alexanderi , I. cockingi , I. cribbi , I. damocles , I. draconis , I. jessicae , I. lynbeazleyae , I. sagmata and I. scanloni ), and differs from I. finitima by at least some of the teeth of the fixed chelal finger being pointed, whereas all teeth are rounded in I. finitima .

It also differs from all other Indohya species for which sequence data are available by a synapomorphy in COI mtDNA: at base 59 there is a substitution to G.

Description (adult). Colour ( Fig. 56 ): carapace and pedipalps red-brown.

Setae and cuticle: setae long, mostly straight and acicular; most cuticular surfaces smooth and glossy.

Chelicera: surface smooth; hand with 6 setae, movable finger with 1 sub-medial seta, all setae acuminate; galea present, long, slender and slightly curved; fixed finger with 14 teeth, larger teeth alternating with smaller teeth; movable finger with 7 small teeth, each approximately same size; with 2 dorsal and 1 ventral lyrifissures; lamina exterior absent; rallum with 7 blades, all blades with anterior spinules, basal blade shorter than others.

Pedipalp ( Fig. 57B ): long and slender; trochanter smooth, 2.34 ×; femur slightly broadened distally, basal third lightly granulate, without dorsal tactile seta, with 3 stout retrolateral setae near base, 5.18 ×; patella broadened distally, smooth, pedicel not strongly pronounced but basal portion slimmer than distal portion, with several small lyrifissures situated basally on dorsal surface, 3.34 ×; chela ( Fig. 57C ): hand ovoid, with prolateral and retrolateral faces lightly granulate, chela (with pedicel) 3.51 ×, chela (without pedicel) 3.36 ×, hand (without pedicel) 1.44 × longer than broad, movable finger 1.31 × longer than hand (without pedicel). Fixed finger with 8 trichobothria, eb, esb and isb in straight row at base of finger, ib situated dorsally at the end of the chelal hand, isb at the basal end of the fixed finger, ib situated on dorsum of chelal hand, it closer to et than to est, et slightly distal to it; movable finger with 4 trichobothria, sb closer to b than to st, st situated much closer to t than to sb; ratio sb–st/sb–b = 1.40, t acuminate. Both fingers straight in lateral view. Fixed finger smooth, movable finger with several prolateral and retrolateral granulations basally. Chelal teeth ( Figs. 57D, E ) juxtadentate, fixed finger with 65, teeth 50, 53, 56-57, 62-65 slightly pointed, 1–49, 52, 55, 58–61 rounded, movable finger with 29, low, but discernible teeth. Venom apparatus present only in movable chelal finger, venom duct long, terminating in nodus ramosus between sb and st.

Cephalothorax: carapace ( Fig. 57A ) sub-rectangular; smooth; anterior margin slightly convex; epistome absent; lateral margins slightly convex; 1.34 × longer than broad; with 12 setae arranged 4: 0: 4: 2: 2; without furrows; eyes absent. Manducatory process distally triangular, with 2 distal setae; pedipalpal coxa with 6 additional setae. Coxa I with anterior margin not modified; chaetotaxy of coxae I–IV: 4: 5: 4: 6.

Legs: femora I and II much longer than patellae I and II, respectively; femora I and II with basal swelling; femora I and II with primary slit sensillum directed transversely; junction between anterior femora and patellae perpendicular; junction between posterior femora and patellae slightly oblique; femora III and IV much smaller than patellae III and IV, respectively; femur + patella IV 3.87 × longer than broad; metatarsi shorter than tarsi; subterminal tarsal seta acuminate; claws smooth, arolium slightly shorter than claws; arolium not divided.

Abdomen: absent.

Dimensions (mm): adult holotype ( WAM T120197 ). Body length? (damaged). Pedipalp : trochanter 0.340 / 0.145 , femur 0.880 / 0.170, patella 0.685 / 0.205, chela (with pedicel) 1.370 / 0.390, chela (without pedicel) 1.31, hand (without pedicel) 0.560, movable finger length 0.735. Carapace 0.610 / 0.455 . Leg IV: femur + patella 0.625 / 0.180, tibia 0.450 / 0.075, metatarsus 0.150 / 0.055, tarsus 0.360 / 0.045.

Distribution and remarks. Indohya finitima has only been collected from subterranean ecosystems on Irvine Island which is situated in the western Kimberley region ( Fig. 6B ). The site is situated within the Northern Kimberley bioregion. The holotype is damaged and its sex cannot be determined as the abdomen is missing ( Fig. 56 ). Nevertheless, there is sufficient morphological and molecular data to demonstrate that it is distinct from all other Indohya species. The species was previously known by WAM identification code Indohya ‘PSE197’.

Conservation assessment. Indohya finitima has been collected from subterranean habitats on Irvine Island, where the surface formations are intact. The species does not appear to meet the status of threatened using the criteria developed by the International Union for Conservation of Nature (2012).

Etymology. The specific epithet refers to the close geographic and phylogenetic relationship this species shares with I. sachsei (finitimus, Latin, adjoining, bordering, near, related) ( Brown 1956).

Figures

FIGURE 6. Maps of north-western Australia depicting recorded distributions of the three epigean species of Indohya from the Kimberley:A, epigean species; B, troglobitic species.

FIGURE 56. Indohya finitima Harvey & Burger, n. sp., holotype adult (WAM T120197):A, dorsal; B, ventral; C, cephalothorax, dorsal. Scale lines = 1.0 mm.

FIGURE 57. Indohya finitima Harvey & Burger, n. sp., holotype adult (WAM T120197):A, carapace, dorsal; B, right pedipalp, dorsal; C, left chela, retrolateral; D, movable finger, chelal teeth, retrolateral; E, fixed finger, chelal teeth, retrolateral. Scale lines = 0.5 mm (Figs. A–C), 0.1 mm (Figs. D, E).