The eels of the genus Nettenchelys, with description of a new species from Taiwan (Teleostei: Anguilliformes: Nettastomatidae)
Author
Smith, David G.
Author
Lin, James
Author
Chen, Hong-Ming
Author
Pogonoski, John J.
text
Zootaxa
2015
4060
1
105
120
journal article
39198
10.11646/zootaxa.4060.1.13
38093659-b690-4784-9a94-8cae00087b82
1175-5326
238161
CF6D51E1-2BBE-480A-9331-E9D4CA4808D8
Genus
Nettenchelys
Alcock 1898
Nettenchelys
Alcock 1898
:149
.
Type
species
Nettenchelys taylori
Alcock 1898
, by monotypy. Feminine.
Diagnosis.
Body elongate, round anteriorly, compressed posteriorly, deepest in middle and tapering at both ends, tail slender and attenuate, its tip delicate and frequently broken. Dorsal fin begins over gill opening or slightly behind, anal fin begins immediately behind anus, the fins confluent with caudal fin. Pectoral fin absent. Head and snout slender, elongate, and slightly depressed, snout projecting beyond tip of lower jaw. Anterior nostril tubular, near tip of snout; posterior nostril located on dorsal surface of head or body, from a point just posterior to eye to dorsal surface of body well behind dorsal origin (
Fig. 1
). Lateral line on body complete; 5 SO pores, 8–10 + 2–4 IO pores, 11–16 POM pores. Teeth small, conical, in narrow bands on jaws and vomer; vomerine tooth patch elongate, sometimes with a median series of enlarged teeth anteriorly.
Species.
Nettenchelys
contains nine known adult species:
N. dionisi
Brito 1989
;
N. erroriensis
Karmovskaya 1994
;
N. exoria
Böhlke & Smith
in
Smith
et al.
1981
;
N. gephyra
Castle & Smith
in
Smith
et al.
1981
;
N. inion
Smith & Böhlke
in
Smith
et al.
1981
;
N. paxtoni
Karmovskaya 1999
;
N. proxima
n. sp.
;
N. pygmaea
Smith & Böhlke
in
Smith
et al.
1981
; and
N. taylori
Alcock 1898
. They are distinguished by the position of the posterior nostril (
Figure 1
), the presence or absence of the median supratemporal pore, infraorbital pore counts, and the form of the vomerine teeth (
Table 1
). A tenth species,
Nettenchelys belottii
(D’Ancona 1928)
, is known only from a larva.
Distribution
. Tropical Atlantic and Indo-West Pacific, rarely collected as adults.
Remarks.
All of the known specimens have regenerated tails. As a result, the total number of vertebrae, an important character in eels, is unknown for any of the species, except by inference from the number of myomeres in larvae.
TABLE 1.
—Distinguishing characters in
Nettenchelys
species. Abbreviations as in Material and Methods. Sources from: 1. Brito (1989); 2. Karmovskaya (1994); 3. Karmovskaya 1999); 4. Smith
et al.
(1981); 5. Smith (1989); 6. This study. (*reported as abdominal vertebrae)
Character
N. dionisi
N. erroriensis
N. exoria
N. gephyra
N. inion
N. paxtoni
N. proxima
n. sp.
N. pygmaea
N. taylori
single row of enlarged vomerine teeth anteriorly Yes No No Yes No No Yes Yes No