Trogolaphysa entreriosensis sp. nov.

Figs 3 F, 12A–G, 13A–B Table 2

Etymology. The epithet refers to province of Entre Rios, Argentina, where the species was collected.

Material examined. Holotype in preparation, ARGENTINA, Entre Rios, P.N. El Palmar, along banks of arroyo El Palmar, S 30.884, W 58.237, 13m elevation, vacuuming grass/sedge in wetland, 14.ii.2014, C.H., Dietrich coll., AR 14-19-2.

Description. Size, 1.4mm.

Color p attern. Light purplish red throughout, more intense on coxae (Fig. 3 F).

Head. Antennae missing in specimen examined. Eyes 8+8, eyes G and H greatly reduced, eye valley with 3 ciliate chaetae. Head dorsally (Fig. 12 A) with 4 anterior (A0, A2, A3, S5) and 2 posterior (Pa5, Pm3) macrochaetae. Pre-labral chaetae ciliate. Distal margin of labrum with 1+1 denticles with independent stalks. Labial triangle with M1M2rEL1L2A1-5: anterior chaetae smooth; r stout and smooth, all other posterior chaetae ciliate. Post-labial field with 8 chaetae between columns I and L.

Body. Body macrochaetae 70/0243+0+6. Thoracic chaetotaxy as in Fig. 12 E, Th. 2 with 1 anterior (a5) and 6 posterior (p3 complex) macrochaetae; Th. 3 without macrochaetae. Abd. 1 chaeta a6 present, rather distant from Smicrochaeta (Fig. 12 B). Chaetotaxy of Abd. 2–3 as in Figs. 12 F–G. Abd. 4 (Fig. 13 A) pseudopore clearly in field posterior to bothriotrix T4; inner macrochaetae A3, B4 and B5 present; A3 almost in line with bothriotrix T2, B4 closer to pseudopore that to B5; lateral macrochaeta E4 enlarged and F2 absent. Abd. 4 posterior chaetae 7+7.

Legs. Trochanteral organ V-shaped, with 16 chaetae. Metathoracic claw complex as in Fig 13 B: tenent hair spatulate, 1.3x as long as unguiculus. Hind claw with 4 inner teeth; basal teeth subequal; proximal unpaired tooth as long as shortest basal tooth; inner teeth spread as 50%, 50%, 74%, 90%. Outer teeth ending on basal quarter of unguis. Unguiculus lanceolate, posterior edge smooth or weakly serrate.

Furcula. Dens with 2 rows of ciliate spines: inner row with 19 spines; outer row with 15 spines. Mucro rectangular (Figs. 12 C–D), 3.4x as long as wide; 0.89x as long as inner margin of metathoracic unguis; with 4 sequential teeth.

Remarks. Among species with known chaetotaxy, T. entreriosensis sp. nov. is unique in having 4 dorsal anterior head macrochaetae in the combination A0, A2, A3, S5, having 3 inner macrochaetae on Abd. 4 in the combination A3, B4, B5, lacking Abd. 4 macrochaetae A5 and F2, and having a rectangular mucro. The new species is most similar to T. geminata from which it differs in color pattern, in carrying head macrochaeta S5 instead of S3, in having Abd. 4 macrochaeta B4 but without A5 and in the absence of Abd. 4 lateral macrochaeta F2. Other species with four dorsal anterior head macrochaetae have a combination of macrochaetae different from the one seen in T. entreriosensis sp. nov. (Table 2).

The rectangular mucro in the holotype first lead me to identified the species as T. berlandi (Denis, 1925), following Cassagnau's (1963) report of that species from Argentina. However, the new species clearly carries two rows of spines on the dens instead of the single row reported by Denis (1925) and Cassagnau (1963). The claw of the new species is intermediate between those described by Denis and Cassagnau: the new species is similar to the individual described by Denis in having four inner teeth, whereas the relatively basal position of the outer teeth resembles that in the material described by Cassagnau.