Aegla ringueleti Bond-Buckup & Buckup, 1994

Diagnosis. Anterolateral spine of carapace reaching base of cornea; protogastric lobes absent; rostrum triangular, of medium length, carinate along its entire length; front narrow; anterior angle of ventral margin of epimera 2 with small tubercle; fourth thoracic sternite raised, with tubercle; proximal outer margin of moveable finger of cheliped without lobe; fingers of cheliped without lobular tooth; palmar crest of cheliped little developed, narrow; inner margin of ventral face of ischium of cheliped with up to three tubercles; dorsal margin of merus of second pereiopod unornamented, with long setae; ventral margin of merus of second pereiopod with scale-shaped tubercles; inner margin of coxa of cheliped with one conical spine. (Modified from Bond-Buckup & Buckup 1994.)

Measurements. Mean length of cephalothorax: 23.19 mm CL (n = 3 males); 21.69 mm CL (n = 4 females). The mean of the PCW/FW ratio (2.04) confirms the narrow front; however, the areola is quadrate (mean AL/AW=1.49 for males and 1.56 for females). Examination of new specimens and new comparative analyses led to modifications in the species diagnosis of Bond-Buckup & Buckup (1994).

New Records. ARGENTINA: Province of Salta, River Calchaqui, near city Cachi. 25º07'16"S, 66º09'31"W; 2346 m, 07.xii.2001 (UFRGS 3207, 12 M, 12 F).

Former distribution. ARGENTINA: Province of Salta, Cachi.

Present distribution. ARGENTINA: Parana River system, Salado River.

Remarks. Aegla ringueleti was described by Bond-Buckup & Buckup (1994) on the basis of only two females, that were deposited in the Senckenberg-Museum, Frankfurt, Germany (SMF). The collection records indicated an altitude of 4500 m. However, the locale where this species was found is quite singular, at a lower altitude than previously recorded, a mountain river with variable water volume. These streams become torrents during the spring melt, and contain little water during the rest of the year. A large population of the species was found, most of medium size, with a few large specimens. The watercourse was more than 20 m wide, only about 20 cm in depth, and had a rocky bottom, with the animals concentrated along the riverbanks. This river, embedded in the Andes, shelters the species that is the most basal ingroup taxon (Perez-Losada et al. 2004), suggesting that A. ringueleti became trapped in the Andes during their uplifting about 65 my ago.