Eptatretus mccoskeri, MCMILLAN, 1999

Mincarone, M. M., Plachetzki, D., McCORD, C. L., Winegard, T. M., Fernholm, B., Gonzalez, C. J. & Fudge, D. S., 2021, Review of the hagfishes (Myxinidae) from the Galapagos Islands, with descriptions of four new species and their phylogenetic relationships, Zoological Journal of the Linnean Society 192, pp. 453-474: 462-463

publication ID

C4F4F7F9-C496-4F28-AF92-0B317DC0EBEF

publication LSID

lsid:zoobank.org:pub:C4F4F7F9-C496-4F28-AF92-0B317DC0EBEF

persistent identifier

http://treatment.plazi.org/id/7C4C4E09-C012-9F14-FF53-FBF0E894CBAF

treatment provided by

Felipe

scientific name

Eptatretus mccoskeri
status

 

EPTATRETUS MCCOSKERI MCMILLAN, 1999  

MCCOSKER’ S HAGFISH

( FIGS 1, 2D, 3C, 5, 6C; TABLES 1–3)

Eptatretus mccoskeri McMillan, 1999: 115   , fig. 2d–g [type locality: Galapagos Islands, 01°06.3’S, 89°06.9’W, depth 704 ft (correct depth 660 ft / 201 m); type series: holotype, CAS 86431 View Materials ; paratypes, SIO 97-75 View Materials (2), USNM 344905 View Materials (1)].

Eptatretus mccoskeri   . – Mok, 2001: 356. – Mok et al., 2001: 1026. – McMillan & Wisner, 2004: 55. – Mincarone & McCosker, 2004: 166. – Møller & Jones, 2007: 64. – McCosker & Rosenblatt, 2010: 172. – Mincarone & Fernholm, 2010: 797. – Knapp et al., 2011: 404. – Ruiz et al., 2011: 30. – Mincarone & McCosker, 2014: 347. – Cruz-Mena & Angulo, 2015: 325. – Angulo & Del Moral-Flores, 2016: 105.

Eptatretus   Eptatretus mccoskeri   . – Møller & Jones, 2007: 64.

Material examined: CAS 86431 View Materials , holotype (310 mm), off SE San Cristobal Island, 01°06’19”S, 89°06’56”W, 201 m depth, submersible Johnson Sea Link   , baited minnow trap, John E. McCosker, 16 November 1995 GoogleMaps   . SIO 97–75 View Materials , paratype (290 mm), and   USNM 344905 View Materials , paratype (284 mm), taken with the holotype   . MCCDRS 9397 COI, 16S, 2(303–304 mm) and   SIO 19-81 View Materials COI, 16S, 2 (310– 310 mm), between Santa Cruz and Santa Fé islands, 00°48’00”S, 90°10’12”W, 155 m depth, Valeska Yamile, sta. G1, baited trap, Douglas Fudge et al., 26 May 2019 GoogleMaps   , 08:01–10:06 h.

Diagnosis: Eptatretus mccoskeri   differs from all congeners, except Eptatretus poicilus Zintzen & Roberts, 2015   from New Zealand, by having eight pairs (seven pairs in one specimen of E. mccoskeri   ) of gill apertures well-spaced and arranged in a near straight line, and a 3/3 multicusp pattern of teeth. Eptatretus mccoskeri   differs from E. poicilus   by its number of trunk pores (38–43 vs. 45–50), number of total pores (69–75 vs. 78–86) and by its colour pattern (body purple to purplish brown vs. body strongly mottled with pale brown, dark brown and white-beige) ( McMillan, 1999; Zintzen et al., 2015).

Description: Body elongated, subcylindrical at prebranchial and branchial regions, laterally compressed at trunk and strongly compressed at tail. Rostrum bluntly rounded. Two bilaterally symmetrical nasal-sinus papillae in the dorsal surface of the nasal sinus. Eyespots conspicuous. Three pairs of barbels on head: first two about equal in size (1.5–2.2% TL) and adjacent to opening of nasopharyngeal duct; third pair longer (1.9–2.9% TL) and immediately adjacent to mouth. Ventral finfold absent (occasionally represented by a white line) or low (1–2 mm high), beginning within anterior 1/3 of trunk, extending backwards to cloaca. Caudal finfold well developed, thin, extending around tail to dorsal surface, ending about over cloaca.

Body proportions (in percentage of TL; description of the holotype followed by range of paratypes in brackets): preocular length 7.1 (5.6–6.3); prebranchial length 25.8 (22.6–26.1); branchial length 10.0 (8.8– 13.5); preventral length 51.6 (38.7–53.4); trunk length 49.7 (49.3–56.1); tail length 15.8 (10.6–16.9); body width at PCD 7.3 (6.9–8.6); body depth at PCD (6.6–8.4); body depth including VFF 8.2 (7.7–9.3); body depth excluding VFF 8.2 (7.4–9.1); body depth at cloaca 7.3 (6.8–14.5); tail depth 8.9 (7.1–9.8).

Counts (description of the holotype followed by range of paratypes in brackets): multicusp pattern 3/3; anterior unicusps 10 (8–10); posterior unicusps 9 (8–10); total cusps 51 (44–51). Prebranchial pores 13 (13–16); branchial pores 7 (6–7); trunk pores 43 (38– 43); tail pores 10 (10–12); total pores 73 (69–75).

Eight pairs of gill pouches corresponding to eight pairs of gill apertures (one specimen with seven pairs of gill pouches and apertures). Gill apertures well-spaced and linearly arranged. Last branchial duct confluent with pharyngocutaneous duct on left side, forming a larger aperture. Posterior tip of dental muscle reaches gill pouches 5–6. Ventral aorta branches at gill pouches 6–7.

Colour (in life): body purple to purplish brown; mouth with white margin; barbels white; eyespots visible, but not prominent; gill apertures with white margins; ventral finfold occasionally lighter than body; caudal finfold with white margin ( Fig. 3). Colour in alcohol darker than that described for live specimens.

Distribution and habitat: Galapagos Islands: known from seven specimens collected in two localities: off south-eastern San Cristobal Island, on the top of a seamount at about 201 m depth; and between Santa Cruz and Santa Fé islands, at 155 m depth ( Fig. 1).

CAS

California Academy of Sciences

TL

Université Paul Sabatier

Kingdom

Animalia

Phylum

Chordata

Class

Myxini

Order

Myxiniformes

Family

Myxinidae

Genus

Eptatretus

Loc

Eptatretus mccoskeri

Mincarone, M. M., Plachetzki, D., McCORD, C. L., Winegard, T. M., Fernholm, B., Gonzalez, C. J. & Fudge, D. S. 2021
2021
Loc

Eptatretus

Moller PR & Jones WJ 2007: 64
2007
Loc

Eptatretus mccoskeri

Angulo A & Del Moral-Flores LF 2016: 105
Cruz-Mena OI & Angulo A 2015: 325
Mincarone MM & McCosker JE 2014: 347
Knapp A & Mincarone MM & Harwell H & Polidoro B & Sanciangco J & Carpenter K 2011: 404
Ruiz D & Chiriboga A & Banks S 2011: 30
McCosker JE & Rosenblatt RH 2010: 172
Mincarone MM & Fernholm B 2010: 797
Moller PR & Jones WJ 2007: 64
McMillan CB & Wisner RL 2004: 55
Mincarone MM & McCosker JE 2004: 166
Mok H-K & Saavedra-Diaz LM 2001: 1026
2001
Loc

Eptatretus mccoskeri

McMillan CB 1999: 115
1999