Indohya adlardi 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 : 34-37

Indohya adlardi Harvey & Burger , n. sp.

( Figs. 1–3 , 9 , 10 )

urn:lsid:zoobank.org:act:A8EA81EA-4372-4363-961E-0126449EBBF9

Material examined. Holotype female. AUSTRALIA: Western Australia: Mesa B, 38.26 km W. of Pannawonica , 21°39′42″S, 115°57′20″E, 22 May–19 July 2012, subterranean troglofauna trap, J. Alexander ( WAM T127062 ).

Paratypes. AUSTRALIA: Western Australia: 1 ♀, Mesa B, 15 km SW. of Pannawonica , MEBRC0022 , 21°39′42″S, 115°57′20″E, 12 July 2014, litter trap, S. Lange ( WAM T134275 ) ; 1 ♀, Mesa B, ca. 40 km W. of Pannawonica , 21°39′37.88″S, 115°56′0.33″E, 7 June 2015, troglofauna scrape, J. Alexander ( WAM T138456 ) ; 1 ♀, Robe Valley, near Mesa B, ca. 39 km W. of Pannawonica , 21°39′33.36″S, 115°56′33.15″E, 6 August–1 October 2015, troglofauna trap, J. Alexander ( WAM T138533 ) ; 1 ♀, Mesa B, RC14MEB0013, 38.1 km W. of Pannawonica , 21°39′45″S, 115°57′18″E, 25 May 2013, haul net, J. Alexander ( WAM T144191 ) ; 1 ♀, Mesa B, site GR15MEB0022, 39.1 km W. of Pannawonica , 21°39′28.64″S, 115°56′38.41″E, 26 July 2012, haul net scrape, J. Alexander ( WAM T144229 ) .

Diagnosis. Indohya adlardi most closely resembles I. rixi and I. sachsei as all three those species have 14 carapaceal setae arranged 4: 2: 4: 2: 2 and they lack eyes ( Fig. 10A ). It differs from them by its larger size, e.g. chela (with pedicel) 1.865 –2.005 (♀) mm.

It also differs from all other Indohya species for which sequence data are available by a synapomorphy in COI mtDNA: at base 47 there is a substitution to G. The three sequenced specimens differ from all other sequenced specimens of Indohya by 18.2–25.5% (Table 2).

Description (adult). Colour ( Fig. 9 ): pale red-yellow; carapace, cheliceral fingers, pedipalp trochanter, femur and patella darker reddish 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 9 (♀) teeth, each approximately same size; movable finger with ca. 12, 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. 10B ): long and slender; trochanter smooth, 2.49–2.61 (♀) ×; femur slightly broadened distally, basal half lightly granulate, without dorsal tactile seta, with 3 stout retrolateral setae near base, 6.71–7.44 (♀) ×; patella slightly broadened distally, smooth, pedicel not strongly pronounced but basal portion slimmer than distal portion, with several small lyrifissures situated basally on dorsal surface, 4.49–4.81 (♀) ×; chela ( Fig. 10C ): hand ovoid, with prolateral face lightly granulate, chela (with pedicel) (♀) 4.77–5.19 ×, chela (without pedicel) 4.49–4.91 (♀) ×, hand (without pedicel) 1.75–1.86 (♀) × longer than broad, movable finger 1.52–1.61 (♀) × 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 = 1.93 (♀), t acuminate. Both fingers straight in lateral view. Fixed finger smooth, movable finger with several prolateral and retrolateral granulations basally. Chelal teeth ( Fig. 10D ) juxtadentate, fixed finger with 97 (♀) teeth, teeth 1–5, 53, 55–56, 59–60, 62, 64, 66, 68–72, 74–97 pointed, remainder rounded, movable finger with ca. 45, low teeth. Venom apparatus present only in movable chelal finger, venom duct long, terminating in nodus ramosus between sb and st.

Cephalothorax: carapace ( Fig. 10A ) sub-rectangular; smooth; anterior margin slightly convex; epistome absent; lateral margins slightly convex; posterior margin straight; 1.38–1.55 (♀) × longer than broad; with 14 setae arranged 4: 2: 4: 2: 2; without furrows; eyes absent. Manducatory process distally triangular, with 2 distal setae; pedipalpal coxa with 7 additional setae. Coxa I with anterior margin not modified; chaetotaxy of coxae I–IV: ♀, 4: 4: 4: 5.

Legs: femora I and II much longer than patellae I and II, respectively; femora I and II with basal swelling; femora I and II each with 2 primary slit sensilla, 1 sub-basally and 1 sub-distally, both directed longitudinally; 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 4.45 × longer than broad; metatarsi shorter than tarsi; subterminal tarsal seta acuminate; claws smooth, arolium slightly shorter than claws; arolium not divided.

Abdomen: tergites not divided; tergal chaetotaxy, 4: 4: 6: 6: 6: 6: 6: 6: 6: 5 (including 2 tactile setae): 4 (including 2 tactile setae): 2; arranged in single rows; sternal chaetotaxy, 9: (2) 7 (2): (2) 5 (2): 8: 8: 8: 8: 8: 6 (including 4 tactile setae): 6 (including 4 tactile setae): 2; setae of anterior genital operculum (sternite II) of ♀ minute; posterior tergites and sternites with several tactile setae; medial sternites without suture line; pleural membrane uniformly granulate; without setae; stigmatic helix present.

Genitalia: with large gonosac that is covered with scattered pores.

Dimensions (mm): holotype female (WAM T127062), followed by 5 other females, when measured. Body length (excluding chelicerae) 2.37 (2.27–2.83). Pedipalp: trochanter 0.455 / 0.180 (0.415–0.450/0.165–0.180), femur 1.310 / 0.190 (1.265–1.345/0.170–0.190), patella 1.045 / 0.220 (1.010–1.035/0.210–0.225), chela (with pedicel) 1.990 / 0.400 (1.865–2.005/0.370–0.410), chela (without pedicel) 1.890 (1.775 –1.880), hand (without pedicel) 0.725 (0.670 –0.715), movable finger length 1.120 (1.020 –1.150). Carapace 0.820 / 0.520 (0.800–0.845/0.520–0.600). Leg IV: femur + patella 0.890 / 0.200, tibia 0.660 / 0.095, metatarsus 0.310 / 0.070, tarsus 0.595 / 0.050.

Distribution and remarks. Indohya adlardi has only been collected from Mesa B in the Pilbara region of Western Australia ( Fig. 5 ), where it occurs in subterranean voids. The species was previously known by WAM identification code Indohya ‘PSE073’.

There are no observable morphological differences between I. adlardi and I. rixi , other than size, e.g. the chela length (with pedicel) is 1.055 mm in the sole male of I. rixi , and 1.865 –2.005 mm in six females of I. adlardi . Although male hyids are generally slightly smaller than females, the size difference between this species pair is considerable with the females of I. adlardi being nearly twice as large as the male of I. rixi . Furthermore, they occur in adjacent but separate mesas in the Robe River Valley ( Fig. 5 ).

Conservation assessment. Mesa B is a small mesa in the Robe River Valley which is scheduled to be developed into an iron ore mine in which the vast majority of the subterranean habitat will be extracted. Like other troglobitic arthropods that occur in the subterranean environment of Mesa B, it is highly unlikely that I. adlardi occurs in any nearby environments, as these mesas are occupied by other species of Indohya . The combination of small distribution and potential loss of available habitat if the mine commences suggests that this species is Vulnerable (B2ab[iii]).

Etymology. This species is named for Robert Adlard (Queensland Museum), in recognition of his contribution to biodiversity research.

Figures

FIGURE 1. Maximum likelihood phylogeny of Hyidae and other neobisioids, based on alignment of concatenated COI, 18S and 28S. Ultrafast bootstrap values are presented for nodes greater than 80%.

FIGURE 2. Maximum likelihood phylogeny of Australian Indohya, using COI, 18S and 28S concatenated dataset. Bootstrap values are presented for all nodes. The genes amplified for each specimen are depicted with black squares in the gene matrix.

FIGURE 3. Maximum likelihood phylogeny of Australian Indohya, using COI. Bootstrap values are presented for all nodes.

FIGURE 5. Maps of north-western Australia depicting recorded distributions of the subterranean species of Indohya from the Pilbara and Cape Range region.

FIGURE 9. Indohya adlardi Harvey & Burger, n. sp.: A–C, holotype female (WAM T127062): A, dorsal; B, ventral; C, cephalothorax, dorsal; D–F, paratype female (WAM T144191): D, dorsal; E, ventral; F, cephalothorax, dorsal. Scale lines = 1.0 mm.

FIGURE 10. Indohya adlardi Harvey & Burger, n. sp., holotype female (WAM T127062):A, carapace, dorsal; B, right pedipalp, dorsal; C, left chela, retrolateral; D, fixed finger, chelal teeth, retrolateral. Scale lines = 0.2 mm (Figs. A, C), 0.5 mm (Fig. B), 0.1 mm (Fig. D).