Monday, August 7, 2017

[Ichthyology • 2016] Bascanichthys gaira • A New Species of Sand Eel Genus Bascanichthys (Anguilliformes: Ophichthidae) from the Caribbean


Bascanichthys gaira 
Moreno, Acero & Grijalba-Bendeck, 2016


ABSTRACT 
A new species of the sand eel genus Bascanichthys (Anguilliformes: Ophichthidae) is described from specimens found inside the stomachs of mature female numbfish Narcine bancroftii. These rays were collected as bycatch in local fisheries, using beach seines in shallow waters (5 to 10 m) in Gaira Bay (Santa Marta, Colombian Caribbean). Bascanichthys gaira n.sp., is described from three specimens and can be distinguished from other species of the genus by its minute pectoral-fin base (12.3- 24.7% of gill-opening length) and its vertebral number (189). 

KEY WORDS: Endemic sand eel, Anguilliformes, Ophichthidae, Colombia, Southern Caribbean.


Figure 1. Bascanichthys gaira n.sp., holotype. INV PEC8147, 477 mm TL, Gaira Bay, Santa Marta, Colombia.
Picture by A. Polanco, MHNM Invemar.

Diagnosis. An elongate, markedly bicolored bascanichthyin, dark brown dorsally and light brown almost cream ventrally, head and snout dark, fins pale without marks, sex unrecognized. Maximum total length 477 mm. Proportions as % of TL: head 4.6-5.3, trunk 47.9-51.7, tail 43.8-47.9; depth (at gill opening) 1.2- 1.5; depth (at anus) 1-1.1; predorsal length 2.1-2.4; snout 12.4-12.7; eye 4.1-5.5; interorbital width 6.9-9.7; pectoral-fin length 6.4-7.0 mm; Pores SO 1 + 3, IO 4 + 2, POM 4 + 2, STC 3. Pectoral fin minute, its base corresponding to 12.3-24.7% of gill-opening length. Uniserial mandibular teeth (Table 1; Figure 2). 

Distribution. All the specimens were collected in Gaira Bay, Santa Marta, Colombia, inside the stomach of mature females of Bancroft’s numbfish Narcine bancroftii, fished as bycatch of the local beach seine fisheries.

 Etymology. This species was named gaira in reference to Bahía de Gaira, where this species was captured. The proposed vernacular name “Colombian Sand Eel” refers to the fact that this species is the first record of the genus Bascanichthys from Colombia and the southern Caribbean.  


Fabián Moreno, Arturo Acero P. and Marcela Grijalba-Bendeck. 2016. A New Species of Sand Eel Genus Bascanichthys (Anguilliformes: Ophichthidae) from the Caribbean. Bol. investig. mar. Costeras. 45(1); 7-14. 

RESUMEN: Una nueva especie de anguila de arena del género Bascanichthys (Anguilliformes: Ophichthidae) del Caribe. Nueva especie de anguila de arena del género Bascanichthys (Anguilliformes: Ophichthidae) es descrita a partir de ejemplares encontrados en el contenido estomacal de hembras maduras de la raya eléctrica Narcine bancroftii. Estas rayas fueron colectadas como parte del bycatch en las pesquerías locales, usando chinchorros playeros en aguas superficiales (5 a 10 m) de la bahía de Gaira (Santa Marta, Caribe colombiano). Bascanichthys gaira sp. n. es descrita a partir de tres ejemplares colectados y es fácilmente diferenciable de otras especies del mismo género debido a su diminuta aleta pectoral (su base representa entre 12.3-24.7% de la longitud de la apertura branquial) y su número de vértebras (189).
PALABRAS CLAVES: Anguila de arena endémica, Angulliformes, Ophichtidae, Colombia, Caribe sur.