A new genus and two new species of congrid eels (Teleostei: Anguilliformes: Congridae) from the Indo-West Pacific, with a redescription and osteology of Chiloconger dentatus.
Author
David G. Smith
Author
Emma S. Karmovskaya
text
Zootaxa
2003
343
1
19
http://www.zoobank.org/urn:lsid:zoobank.org:pub:7B370603-F5CD-4C1D-AB36-331D394C8473
journal article
z00343p001
Chiloconger Myers and Wade, 1941
Chiloconger Myers and Wade, 1941
: 65
Type species:
Chiloconger labiatus Myers and Wade, 1941
: 66.
Diagnosis. Body moderately elongate, preanal length greater than 40% TL; tip of tail blunt and stiffened, caudal fin reduced; dorsal fin begins over posterior part of appressed pectoral fin; dorsal- and anal-fin rays unsegmented; upper end of gill opening opposite upper part of pectoral-fin base, not enclosing pectoral fin; snout short and blunt, eye large, its diameter slightly greater than snout length; well developed, broadly rounded and elevated flange on upper lip, covering a hollowed-out area; adnasal pore present in at least one species, second and fifth infraorbital pores present, but third and fourth absent; maxillary and mandibular teeth irregularly biserial or triserial, not forming a cutting edge; lateral ethmoid process present, supraoccipital present, posterior end of urohyal simple (not trifurcate).
Relationships. Smith (1989: 490) observed that the
Bathymyrinae
could be divided into two groups. One group contains the genera
Ariosoma
,
Bathymyrus
, and
Parabathymyrus
and is characterized as follows: supraoccipital bone absent, urohyal trifurcate, adnasal pore absent, third and fourth infraorbital pores present, leptocephali with lateral pigment consisting of a series of short, oblique rows of tiny melanophores on myosepta. The other group contains
Paraconger
and
Chiloconger
and is characterized as follows: supraoccipital bone present, urohyal simple, adnasal pore usually present, third and fourth infraorbital pores absent, leptocephali with lateral pigment consisting of a single series of moderately large melanophores along midlateral line. At the time, Smith had no detailed information on
Chiloconger
, but he assigned it to the
Paraconger
group on the basis of retained larval pigmentation in a small specimen. Information presented here (see below) confirms Smith's conclusion;
Chiloconger dentatus
has a supraoccipital and a simple urohyal. In addition,
Chiloconger philippinensis
, at least, has an adnasal pore, and both species lack the third and fourth infraorbital pores.
Key to species
1a. Predorsal length 20-26 % TL, preanal LL pores 19-27, vertebrae 118-122 ................. ............................................................................................
C. dentatus
(eastern Pacific)
1b. Predorsal length 18-19 % TL, preanal LL pores 36-39, vertebrae 113-115 ................. ..................................................................................
C. philippinensis
(western Pacific)