Indohya arcana 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 : 45-47

Indohya arcana Harvey & Burger , n. sp.

( Figs. 1–3 , 17 , 18 )

urn:lsid:zoobank.org:act:702077AF-FC70-4698-AA78-AD7247256DAC

Material examined. Holotype deutonymph. AUSTRALIA: Western Australia: Yarrie Ridge , bore YP006, 20°36′33.6″S, 120°19′25.4″E, 8 November 2008, troglofauna trap, P. Bell, B. Vine, E. Ridley ( WAM T151337 ).

Diagnosis. Indohya arcana is a blind troglobite that differs from all other Indohya species for which sequence data are available by six synapomorphies in COI mtDNA: at base 72 there is a substitution to C; at base 83 there is a substitution to A; at base 102 there is a substitution to G; at base 119 there is a substitution to A; at base 242 there is a substitution to T; and at base 363 there is a substitution to G. The single sequenced specimen differs from all other sequenced specimens of Indohya by 21.4–30.2% (Table 2).

Description (deutonymph). Colour ( Fig. 17 ): Very pale, yellow-white.

Chelicera: hand with 5 setae, movable finger with 1 sub-medial seta.

Pedipalp: trochanter 2.33 ×, femur 5.53 ×, patella 3.36 ×, chela (with pedicel) 4.21 ×, chela (without pedicel) 4.03 ×, hand (without pedicel) 1.59 × longer than broad, movable finger 1.45 × longer than hand (without pedicel). Fixed finger with 6 trichobothria ( Fig. 18 ), eb, est, et, ib, ist and it present; movable finger with 2 trichobothria, b and t present. Fixed chelal finger with 42 teeth, low, juxtadentate, and mostly quadrate; movable chelal finger with 20 teeth, low and juxtadentate.

Cephalothorax: carapace 1.01 × longer than broad; with 11 setae, arranged 4: 0: 3: 2: 2; without furrows; eyes absent. Coxal chaetotaxy 3: 4: 3: 3.

Legs: metatarsi and tarsi not fused.

Abdomen: tergal chaetotaxy 4: 4: 6: 5: 6: 6: 6: 6: 6: 4 (including 2 tactile setae):? (including 2 tactile setae): 2; sternal chaetotaxy 0: (0) 2 (0): (1) 4 (1): 6: 6: 6: 6: 6: 6 (including 2 tactile setae): 4 (including 2 tactile setae): 2.

Dimensions (mm): holotype ( WAM T151337 ). Body length 1.24. Pedipalp: trochanter 0.210 / 0.090 , femur 0.525 / 0.095, patella 0.370 / 0.110, chela (with pedicel) length 0.820 / 0.195, chela (without pedicel) length 0.785, hand (without pedicel) length 0.310, movable finger length 0.450. Carapace 0.415 / 0.410.

Distribution and remarks. Indohya arcana is a blind, troglobitic species currently represented only by a single deutonymph but, based on available sequence data, it is different from other species. The species was previously known by WAM identification code Indohya ‘PSE177’.

Conservation assessment. Indohya arcana has been collected from a single rocky outcrop, Yarrie Ridge ( Fig. 5 ), which has a total area of ca. 20 km 2. This most likely represents its maximum area of occupancy. It therefore represents an extreme short-range endemic species ( Harvey 2002). Although the ridge has an active iron ore mine at the southern edge, the species does not 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 use of molecular sequence data to establish that this nymphal specimen represents a distinct species (arcanus, Latin, shut up, secret, private, mysterious) ( Brown 1956).

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 17. Indohya arcana Harvey & Burger, n. sp., holotype deutonymph (WAM T151337): A, dorsal; B, ventral; C, cephalothorax, dorsal. Scale lines = 1.0 mm.

FIGURE 18. Indohya arcana Harvey & Burger, n. sp., holotype deutonymph (WAM T151337): left chela, retrolateral. Scale line = 0.2 mm.