Limnesia (Limnesia) multiscutata, Smit, Harry, 2013

Smit, Harry, 2013, New records of water mites mainly from Vogelkop, New Guinea (Acari: Hydrachnidia), with the description of one new genus and thirteen new species, Zootaxa 3716 (2), pp. 207-235 : 210-212

Limnesia (Limnesia) multiscutata n. sp.

( Figures 8–13 )

Material examined. Holotype female (fluid, palp and I-, II-L and IV-L mounted), stream Ilik, near Lake Gita, Anggi Lakes, West Papua province, New Guinea, Indonesia, 17-xi-2011, 1° 21.423 S 133° 58.553 E, alt. 1912 m asl (RMNH). Paratype: one female, same data as holotype. (RMNH).

Diagnosis. Idiosoma with two large medial plates surrounded by a pair of frontal plates and five pairs of lateral and posterior plates; first and second legs modified, palp very stocky.

Description. Female: Idiosoma ventrally 980 (1004) long and 656 (637) wide, dorsally 923 (964) long. Integument soft. Dorsum with two large medial plates, anterior plate 259 long and 227 wide, posterior plate 267 long and 300 wide, surrounded by a pair of frontal plates and five pairs of lateral and posterior plates varying in size, with the middle pair of plates being the largest. Dorsal glandularia on separate platelets. Coxal plates surrounded by a large area of secondary sclerotization. First coxal plates fused medially, extending beyond anterior idiosoma margin. Glandulae Limnesiae with their associated setae located medially on third coxal plates. Third and fourth coxal plates fused to one plate. Genital field 204 long and 164 wide, with three pairs of acetabula, lengths of Ac- 1–3 66, 50 and 70, respectively; each genital flap with five small setae. Pregenital sclerite 160 wide, postgenital sclerite a large plate 216 long and 227 wide. Posteriorly of postgenital plate two pairs of large plates, anterior pair 176 long, posterior pair 150 long. Palp very stocky, PII bulging ventrally with a short and fine peg-like seta, not inserted on a setal tubercle, ventral margin of PIV with an extension with two hair-like setae and one stout seta. Lengths of PI-PV: 28, 126, 60, 74, 50. First and second legs somewhat modified, especially segments I- and II-leg- 4 and -5, with an expanding ventral margin; I-leg-5 ventrally with six heavy setae, II-leg-5 ventrally with seven heavy setae. I- and II-leg-4 posteroventrally with three heavy setae. Third and fourth leg not modified in such a way. IV-leg-3 and -4 ventrally with six and seven pinnated setae; IV-leg-6 ending in a long seta. Legs I–III with a claw, without claw blade and with a minute clawlet; swimming setae absent.

Male: Unknown.

Etymology. Named for the high number of dorsal and posteroventral plates.

Remarks. Within the genus Limnesia , the occurrence of plates and platelets is not unusual. However, most species have two large dorsal plates, occasionally the anterior plate is divided. A configuration of the dorsal and ventral plates as in the new species, is not found in any other Limnesia species. Other unusual characteristics are the very stocky palp, not found in other species of the Oriental and Australasian regions, and the modified first and second leg. It is possible that the new species must be placed in a subgenus of its own, but this can only be decided after the male is known. A rheophilic species.

Figures

FIGURES 8 – 13. Limnesia multiscutata n. sp., holotype female: 8. Dorsal view; 9. Ventral view; 10. Genital field; 11. Palp; 12. I-leg- 4 – 6; 13. IV-leg- 4 – 6. Scale bars: 8 – 9 = 200 µm, 10 – 13 = 50 µm.