Rhencus macracanthus (Günther, 1864)

Angulo, Arturo, 2021, New records and range extensions to the Costa Rican freshwater fish fauna, with an updated checklist, Zootaxa 5083 (1), pp. 1-72 : 10

11) Rhencus macracanthus (Günther, 1864) ;

Haemulidae .

Longspine Grunt; Corocoro Coche, Ronco Espina Larga, Roncacho Gordo ( Fig. 3E ).

Diagnosis: This species differs from the other species of the family occurring in the freshwaters of the country (Pacific) by the following combination of characters: pectoral fins very long, exceeding the end of the pelvic fins and reaching the level of the anus [vs. pectoral fins short, not reaching the end of the pelvic fins in Pomadasys empherus Bussing, 1993 and Rhonciscus bayanus ( Jordan & Evermann, 1898)]; lateral line scales 41–46 [vs. 50–54 in Haemulopsis leuciscus (Günther, 1864) , 47–51 in Pomadasys branickii (Steindachner, 1879) and 50–51 in R. bayanus ); dorsal fin rays 13 (vs. 14 in H. leuciscus and 11–12 in P. branickii , P. empherus and R. bayanus ); and second anal spine longer and thicker than the third anal spine (vs. second anal spine shorter and thinner than the third anal spine in H. leuciscus ).

Basis of the record: Three specimens were captured in the río Lagarto, Chomes, Puntarenas (10.08320, -84.92064), at 15 m. a.s.l., on September 1, 1979, by William Bussing et al. (UCR 1268-025).

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

Figures

FIG. 3. New country records. (A) Mugil incilis, specimen captured in the Río Pacuare, near the mouth of the river, Siquirres, Limón (10.219424, -83.284898), at 8 m.a.s.l., on July 22, 2004, by Jorge Picado (UCR 2835-005). (B) Oligoplites saliens, specimen captured in the Caño Palma, near the Caño Palma Biological Station, Pococí, Limón (10.5938, -83.52731), at 11 m.a.s.l., on February 22, 2019, by Nathan Lovejoy et al. (UCR 3311-001). (C) Oreochromis aureus, specimen captured the Río Pacuar (Térraba river basin), 4 km SE of San Isidro del General, under bridge on road San Isidro-Dominical, San José (09.35264, -83.72790), at 619 m.a.s.l., on March 25, 2013 by Carlos Garita (UCR 3018-001). (D) Pangasianodon hypophthalmus, specimen captured in the laguna San Sebastian, Caño Negro, Alajuela (10.8630, -84.7807), at 41 m.a.s.l., on September 29, 2021, by Bryan Castro and Jader Urbina. (E) Rhencus macracanthus, specimen captured in the Río Lagarto, Chomes, Puntarenas (10.08320, -84.92064), at 15 m.a.s.l., on September 1, 1979, by William Bussing et al (UCR 1268-025). (F) Thalassoma bifasciatum, specimen captured in the Quebrada Cocles (Matina river basin), 2.5 km SE of Puerto Viejo, near the bridge on El Tucán-Cocles road, Limón (9.64221, -82.73588), at 22 m.a.s.l., on August 20, 2020, by Walter Carranza. (G) Trinectes fluviatilis, specimen captured in the Quebrada Cocal Amarillo, 5 Km N of Pavones, on the Puerto Pilón-Pavones road, Puntarenas (8.43643, - 83.09660), at 26 m.a.s.l., on March 30, 2021, by Arturo Angulo et al. (H) Trinectes xanthurus, specimen 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). Range extensions. (I) Achirus declivis, specimen captured in the Río Moín, at the Puerto Fluvial JAPDEVA, Limón (09.99745, -83.08077), at 7 m.a.s.l., on December 14, 2006, by Karina Rodríguez (UCR 2761-003). (J) Amatitlania myrnae, specimen captured in the Río Estrella, Valle La Estrella, Limón (9.77552, -82.93240), at 13 m.a.s.l., on April 6, 2014, by Arturo Angulo. (K) Amphilophus citrinellus, specimen captured in the Río Bebedero, near Paso Real, Cañas, Guanacaste (10.43318, -85.15697), at 32 m.a.s.l., on August 7, 2021, by Luis Bolivar Montero-Chacón. (L) Brachyrhaphis olomina, specimens captured in an unnamed pound in the Reserva Biológica Monteverde, Altos de San Luis, Monteverde, Puntarenas (10.31667, -84.80932), at 1486 m.a.s.l., on July 6, 2019, by Arturo Angulo.