Litarachna lopezae, Pesic, Vladimir, Chatterjee, Tapas, Alfaro, Monica & Schizas, Nikolaos V., 2014

Pesic, Vladimir, Chatterjee, Tapas, Alfaro, Monica & Schizas, Nikolaos V., 2014, A new species of Litarachna (Acari, Hydrachnidia, Pontarachnidae) from a Caribbean mesophotic coral ecosystem, ZooKeys 425, pp. 89-97 : 91-93

Taxon classification Animalia Trombidiformes Pontarachnidae

Litarachna lopezae sp. n. http://zoobank.org/4C577A5A-9287-476A-A611-12DD3667687CFigs 1 A–B, 2, 3 A–E

Type series.

Holotype male, dissected and slide mounted, Puerto Rico, Bajo de Sico, 18°14'41.676"N, 67°24'45.791"W, depth 69.5 m, 20.iv.2011. Paratypes: three males, two females, one deutonymph, same data as holotype, one male and one female dissected and slide mounted.

Diagnosis.

Adults. Idiosoma small (L 250-300 µm); first coxal plates fused; glandularium-like structure fused with Cx-IV, a pair of small platelets with (according to Wiles et al. 2002) coxoglandularia 4 and associated setae free in the integument near the lateral posterior apodemes of Cx-IV; ventral margin of P-4 with a setal tubercle and a small peg-like seta.

Description.

General features - First coxal plates fused medially; suture lines Cx-I/II complete, suture line Cx-II/III and Cx-III/IV incomplete. Posterior margin of Cx-IV with two pairs of apodemes of moderate length, the medial longer than lateral ones, extending beyond anterior margin of genital field; glandularium-like structure on the outer side of lateral posterior apodemes of Cx-IV, fused with the fourth coxal plates; a pair of small platelets with coxoglandularia 4 and associated setae free in the integument near the lateral posterior apodemes of Cx-IV; posterior to the genital field a pair of platelets with three pores, and three pairs of small wheel-like acetabula, with relatively few radiating spokes. Excretory pore unsclerotized, near posterior end of idiosoma. Palp: ventral margin of P-2 concave without extension; ventral margin of P-4 with a setal tubercle and a small peg-like seta. Legs (Fig. 3C): swimming seta numbers: III-L-5, 1; IV-L-4, 1; IV-L-5, 1. Male: genital field consisting of a sclerotized ring with four pairs of setae; four pairs of perigenital setae free in integument around genital field. Female: pre and postgenital sclerites bowed.

Deutonymph. As in adults but lacking genital field; glandularium-like structure free in the integument on the outer side of lateral posterior apodemes of Cx-IV.

Measurements. Male (holotype, in parentheses paratype, n = 1) - Idiosoma (ventral view, Figs 1A, 2) L 258 (268), W 234 (230); coxal field L 116 (106), Cx-III W 154 (158); ring-shaped genital plate L 29 (31), W 25 (24); chelicera total L (116). Palp (Figs 3A-B): total L 183 (182), dL/H, L/H ratio: P-1, 17/12, 1.38 (16/12, 1.3); P-2, 52/28, 1.89 (53/29, 1.86); P-3, 22/23, 0.97 (23/23, 1.0); P-4, 67/17, 4.0 (67/17, 4.0); P-5, 25/10, 2.5 (23/10. 2.4); dL P-2/P-4 ratio 0.78 (0.79); dL of I-L-3-6: 35, 34, 53 (52), 71 (73); I-L-6 H 17 (15), I-L-6 dL/H ratio 4.3 (4.7); dL of IV-L-2-6: 35, 42, 68, 88, 88.

Female - Idiosoma (ventral view, Fig. 1B) L 295, W 237; coxal field L 118, Cx-III W 160; genital field L 44, pregenital sclerite W 34, postgenital sclerite W 35; chelicera total L 134. Palp (Fig. 3D): total L 190, dL/H, L/H ratio: P-1, 16/12, 1.3; P-2, 59/31, 1.9; P-3, 19/24, 0.78; P-4, 71/17, 4.2; P-5, 25/11, 2.35; dL P-2/P-4 ratio 0.83; dL of IV-L-4-6: 74, 91, 92.

Deutonymph - Idiosoma (ventral view, Fig. 3E) L 220, W 190; coxal field L 90, Cx-III W 119; palp: total L 129, dL/H, L/H ratio: P-1, 13/9, 1.4; P-2, 34/20, 1.7; P-3, 17/17, 1.0; P-4, 48/13, 3.7; P-5, 17/7, 2.46 dL P-2/P-4 ratio 0.71.

Etymology.

This species is named after the famous Puerto Rican singer Jennifer Lopez.

Remarks.

Six Litarachna species have their first coxal plates fused, i.e., Litarachna degiustii Cook, 1958 (Caribbean Sea - Cook 1958, Pešić et al. 2008), Litarachna amnicola Cook, 1986 (Tasmania - Cook 1986, Pešić and Smit 2009), Litarachna brasiliensis Smit, 2007 (Brazil - Smit 2007), Litarachna caribica Pešić, Chatterjee & Schizas, 2008 (Caribbean Sea - Pešić et al. 2008), Litarachna indica Pešić, Chatterjee & Ingole, 2012 (West Indian coast - Pešić et al. 2012a) and Litarachna minuta Pešić, Chatterjee & Marshall, 2013 (Brunei Darussalam - Pešić et al. 2013).

Due to the glandularium-like structure fused with posterior margin of Cx-IV, Litarachna lopezae sp. n. most closely resembles to Litarachna minuta , a species known from a single female from Brunei Bay, but differs by a pair of small platelets with coxoglandularia 4 and associated setae lying free in the integument, not fused with Cx-IV (fused in Litarachna minuta ).

Moreover, peg-like seta at the base of P-4 ventral projection separates new species from Litarachna minuta and other species with fused first coxal plates.

Habitat.

The mites were collected from 69.5 m depth. The greatest depth at which pontarachnid mites have been recorded previously was reported by Pešić et al. (2012b) who found Pontarachna nemethi in a mesophotic coral ecosystem near Vieques Island of Puerto Rico at 67 m depth.

Distribution.

Only known from the type locality.