Eptatretus poicilus Zintzen & Roberts, 2015
Mottled hagfish

Family:  Myxinidae (Hagfishes), subfamily: Eptatretinae
Max. size:  92.1 cm TL (male/unsexed)
Environment:  bathydemersal; marine; depth range 110 - 842 m,
Distribution:  Western Pacific: endemic to the Three Kings Islands of New Zealand (Ref. 115309).
Diagnosis:  Diagnosis: 8 pairs of gill pouches and gill openings, strongly mottled with pale brown, dark brown, and white-beige body colour, 3/3 multicusps, and 77–86 total slime pores; distinguished from all other myxinids except Eptatretus gomoni, Eptatretus luzonicus, Eptatretus indrambaryai, Eptatretus okinoseanus, and Eptatretus octatrema by having 8 gill pouches associated with 8 branchial openings; differs from those 5 Indo-Pacific species by having 3-cusp multicusps on the posterior row of teeth (versus 2-cusp multicusps). (Ref. 115309). Description: 3/3 multicusp pattern; anterior unicusps, 11 (paratypes, 10–12; additional material, 9–12); posterior unicusps, 10 (paratypes, 9–11; additional material, 9–12); left-side cusps, 27 (paratypes, 25–28; additional material, 24–30); prebranchial pores, 15 (paratypes, 13–16; additional material, 13–17); branchial pores, 7 (paratypes, 6–8; additional material, 6–9); trunk pores, 46 (paratypes, 45–50; additional material, 43–51); tail pores, 10 (paratypes, 10–13; additional material, 9–13); total pores, 78 (paratypes, 78–86; additional material, 77–86); 8 pairs of gill pouches associated with 8 pairs of gill apertures (9 pouches and 9 apertures on one specimen in additional material); morphometrics, as percentage of TL; preocular length, 6.1% (5.3–6.7%); prebranchial length, 23.7% (21.6–24.1%); branchial length, 8.8% (7.9–10.6); trunk length, 53.1% (50.4–55.0%); tail length, 15.6% (14.3– 16.5%); greatest body depth including ventral finfold, 7.9% (7.1–9.4%); greatest body depth excluding ventral finfold, 7.7% (6.9–9.0%); depth at pharyngocutaneous duct: 8.0% (6.6–8.0); depth at cloaca, 8.0% (6.5–8.6%); tail depth, 9.6% (8.1–9.8%); body subcylindrical, slightly deeper than wide at prebranchial and branchial regions, laterally compressed at trunk and strongly compressed at tail; rostrum bluntly rounded; 2 minute bilaterally symmetrical nasal-sinus papillae in the dorsal surface of the nasal sinus (sometimes difficult to observe); eyespots usually well defined, circular to elliptical in shape, white to pale pink; 3 pairs of barbels on head, 1st 2 subequal in size 1.2–1.4% TL, (1.2–2.1% TL), 3rd one longer 1.9% TL (1.6–2.4% TL), and adjacent to oral cavity; ventral finfold small, 1.3 mm (0.7–2.0 mm), no ventrolateral branchial finfolds; its origin difficult to assess and located within anterior 59% (51–61%) of body length, extending to cloaca; caudal finfold rounded, thick, beginning immediately posterior to edge of cloaca, extending around tail to dorsal surface, ending about over cloaca; gill aperture 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 6th (5th to 7th) gill pouches (counting from head), with length 24.6% TL (24.8–28.9% TL); ventral aorta branches at 8th (7th to 8th) gill pouch (Ref. 115309). Colour: distinct body coloration unique in New Zealand Myxinidae; body strongly mottled with pale brown, dark brown, and white-beige, usually with 2 or 3 distinct colours in a single individual; pattern irregular but always with well-defined margins separating the different colours; caudal finfold sometimes partly pink; eyespots well defined, white to pale pink; barbels dark brown with white tips or mottled, or with a combination of these 2 patterns; slime pore contours usually of the same colour as the body, but sometimes contrasting with a paler (white) rim; branchial apertures and pharyngocutaneous duct openings white to pink (Ref. 115309).
Biology:  From observations of baited videos, this hagfish is much less active feeding on the bait, and is less inclined to produce slime; possible that the colour pattern of this species offers good camouflage in deep-sea reefs or habitats composed of sand patches over hard substrate, which was also abundant in the Three Kings area (Ref. 115309).
IUCN Red List Status: Not Evaluated (N.E.) Ref. (130435)
Threat to humans:  harmless


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