Australiobates elongatus, 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 : 215

Australiobates elongatus n. sp.

( Figures 19–23 )

Material examined. Holotype female, Unnamed stream crossing road to Mokwam, West Papua Province, New Guinea, Indonesia, 1° 0 0.608 S 133° 53.863 E, alt. 1480 m asl, 10-xi-2011. Paratype: female, same data as holotype.

Diagnosis. Idiosoma elongated, dorsum with large anterior plate with the postocularia, all dorsoglandularia lying on small separate small platelets; in addition, dorsum with seven pairs of small platelets; PIII with 6+3 setae medially and a long dorsodistal seta.

Description. Female: Idiosoma 462 (437) long and 292 (259) wide, elongated in shape. Dorsum reticulated with elongated meshes and with one large anterior plate with the postocularia, 200 long and 162 wide. All dorsoglandularia lying separate on small platelets; in addition, seven pairs of small platelets. Cx-I extending beyond anterior idiosoma margin. Coxal plates long, especially Cx-I – Cx-III. Cx-I and cx-II fused to one plate, as are Cx-III and Cx-IV. Anterior and fourth coxal plates with short apodemes. Posterior and lateral margin of fourth coxal plates with secondary sclerotization. Genital plates triangular, 66 long, with three pairs of acetabula, Ac- 1–3 28–30, 24–28 and 20 long, respectively. Lengths of PI-PV: 24, 56, 70, 62, 30. PIII medially with 6+3 setae and a long dorsodistal seta (probably lost in the holotype, but well developed in paratype), ventral margin of PIV with two heavy, blunt setae. Lengths of I-leg-4–6: 74, 82, 60; I-leg-5 with two short, pointed ventrodistal setae located close to each other (and therefore only one visible in the illustrated leg). Lengths of IV-leg-4–6: 148, 160, 100. Legs without swimming setae.

Male: Unknown.

Etymology. Named for the elongated idiosoma shape.

Remarks. The new species is characterized by its elongated idiosoma and the shape of dorsal plate and platelets. There are only a few more Australiobates species with dorsal plates, but clearly different in plate arrangement, i.e. A. ventriscutatus Cook, 1986 from Australia (one large dorsal plate, only in male), A. longiseta and A. reticuloides (large anterior plates paired). The palp of the paratype differs strongly from the holotype in the absence of the setae of PIII, the ventral margin of PIV with two pointed setae (one broken off) and a more slender PV. Given the similar idiosoma shape and genital field, however, I do not think the paratype represents a different species. More New Guinean Australiobates species show a remarkable variation in the setation of the palp, e.g. A. reticulatus and A. reticuloides (see Wiles 1997, figures 7B, D and G).

Figures

FIGURES 19 – 23. Australiobates elongatus n. sp., 19 – 21, 23 holotype female, 22 paratype female: 19. Dorsal view; 20. Ventral view; 21. Palp; 22. Palp; 23. I-leg- 4 – 6. Scale bars = 50 µm.