14) Trinectes xanthurus Walker & Bollinger, 2001;

Achiridae .

Yellow Tail Sole; Lenguado Redondo Rabo Amarillo (Fig. 3H).

Diagnosis: This species can be easily identified from the other species of the family occurring in the freshwaters of the country (Pacific side) by the coloration pattern [eye-side brown, with faint, thin dark crossbars and dots; dorsal and anal fins dark brown; caudal fin light yellow; blind-side light grey-brown (anterior half) to dark grey-brown (posterior half); see Krupp (1995) and Robertson & Allen (2015)].

Basis of the record: Thirty-two specimens were captured in the río Tempisque (Tempisque River basin), at Puerto Humo, Guanacaste (10.31653, -85.35365), at 9 m. a.s.l., on January 25, 1976, by William Bussing et al. (UCR 0970-005).

Remarks: This species inhabits estuarine areas and coastal environs; it could be considered as an opportunistic visitor of freshwater ecosystems (Robertson & Allen 2015).