Neobythites pako, Uiblein & Nielsen, 2023

Uiblein, Franz & Nielsen, Jørgen G., 2023, Five new ocellus-bearing species of the cusk-eel genus Neobythites (Ophidiidae, Ophidiiformes) from the West Pacific, with establishment of three new species groups, Zootaxa 5336 (2), pp. 179-205 : 197-201

Neobythites pako n. sp.

urn:lsid:zoobank.org:act:B3E4CA7D-F0FD-41EF-A884-451331786136

Figures 3 , 6 , 7 ; Tables 1 , 5 , 6

Holotype. MNHN 2006-0337 , 165 mm SL, Solomon Sea, 8°6′25.2″S, 157°23′2.4″E, Salomon 2 cruise, R / V Alis, st. CP 2286, 248– 253 m depth, 6 Nov. 2004.

Diagnosis. Hind margin of preopercle with very short spine; dorsal-fin rays 92; anal-fin rays 77; pectoral-fin rays 28; precaudal vertebrae 13; total vertebrae 56; pseudobranchial filaments 2; long rakers on anterior gill arch 10; head length 22% SL; pelvic-fin length 14% SL, fins not reaching anus; orbit length 4.5% SL and 21% HL; longest gill filament 1.9% SL and 8.8% HL; dorsal fin with central ocellus placed well behind vertical line through anus, spot distance 46% SL and spot covers 7 dorsal-fin rays, not extending ventrally onto body; ocellus spot dark brown; posterior two-thirds of anal fin black; no vertical bars on body; otolith length 4.8% SL, sulcus length 3.8% SL, and ostium height 17% sulcus length and 25% ostium length.

Description. The principal meristic and morphometric characters are shown in Table 5 . Elongate fish with complete lateral line; head and body covered by deciduous, cycloid scales; origin of dorsal fin above middle of pectoral fin; origin of anal fin slightly in front of midpoint of fish; snout blunt and equal in length to diameter of eye window; very short spine on hind margin of preopercle; opercular spine short and pointed; anterior gill arch on both sides with 4 short and 2 long rakers on upper branch, one long raker at angle, and 7 long and 6–8 short rakers on lower branch; longest filaments on anterior gill arch 8.8% HL and longest raker on anterior gill arch 10% HL.

Sagittal otolith ( Fig. 3E ). Otolith peanut-shaped, ventrally rounded, dorsally and anteriorly flattened, posteriorly blunt, its depth 1.7 times in its length; sulcus large, 1.3 times in otolith length; ostium 1.5 times in sulcus length; ostium depth 5.4 times in sulcus length and 3.6 times in ostium length.

Dentition. Premaxillaries, palatines, and dentaries with many small, pointed, close-set teeth in irregular rows; vomer boomerang-shaped with many, pointed teeth; two median basibranchial tooth patches, anterior one long and narrow and posterior one small and circular.

Axial skeleton. Precaudal vertebrae 13, all with pointed tip; anterior neural spine almost half length of second spine; neural spines on vertebrae 1–9 somewhat depressed, parapophyses present on vertebrae 8–13, pleural ribs on vertebrae 3–13 and epipleural ribs indistinct; basis of neural spines 4–13 enlarged.

Colour. Preserved fish ( Fig. 6A ). Body and head of preserved HT rather uniformly pale brown, slightly darker dorsally and in snout region, gill cover anteriorly gray brown, posteriorly pale, lateral line indistinct, abdomen pale gray anterior of anus; single ocellus placed well behind vertical line through anus at body midpoint, central-ocellus spot dark brown, slightly larger than orbit diameter, covering 7 dorsal-fin rays, not extending onto body below dorsal fin, ocellus ring pale, rather indistinct on folded fin, becoming more distinct when fin is raised; dorsal fin anterior and behind ocellus pale gray brownish, pigmentation becoming somewhat more intense on posterior third towards caudal fin; anal fin almost entirely covered with continuous dark brown stripe behind vertical line through posterior ocellus spot edge; pelvic and pectoral fins hyaline.

Etymology. The new species name “ pako ” is used as a noun in apposition and honours the son of the first author, Francisco “Pako” Uiblein.

Distribution and size. Only known from the HT (165 mm SL), caught in bottom trawl in eastern Solomon Sea at 248–253 m depth.

Figures

FIGURE 3. Neobythites otoliths. (A) N.superocellatus n. sp., HT, MNHN 2021-0457, Solomon Sea (M. Krag). (B) N. japonicus n. sp., HT, KAUM -I. 37071, off Okinawa (from left side of head, shown side-reversed; M. Krag); (C) N. jonathan n. sp., HT, MNHN 2002-3883, Solomon Sea (C. Høegh-Guldberg); (D) N. zora n. sp., HT, ZMUC P771324, Fiji (C. Høegh-Guldberg); (E) N. pako n. sp., HT, MNHN 2006-0337, otolith number MNHN-ICOT-001969, Solomon Sea (M. Krag); (F) N. malayanus, ZMUC P77742, Lombok (C. Høegh-Guldberg); all otoliths from right side of head except for (B); with 1 mm scale bars.

FIGURE 6. Four species of the steatiticus group. (A) Neobythites pako n. sp., HT, MNHN 2006-0337, SL 165 mm, Solomon Sea (side-reversed; M. Krag), (B) N. malayanus ZMUC P77742, 138 mm SL, off Lombok (listed in Uiblein & Nielsen 2018; M. Krag); (C) N. stefanovi, ZMUC P77841, PT, 198 mm SL, Gulf of Aden (listed in Uiblein & Nielsen 2018; M. Krag); (D) N. monocellatus, MOVI 39139, 97 mm SL, off E Brazil (listed in Nielsen et al. 2009; G. Brovad); with 10 mm scale bars.

FIGURE 7. Plots of four morphometric characters and SL for visual comparisons between N. pako n. sp. and N. malayanus (the latter separated into 4 populations).

Tables

TABLE 5. Meristic, morphometric, quantitative colour, and otolith characters in Neobythites pako n. sp. and the eight other steatiticus group species.

	N. pako n. sp.	N. gloriae		N. lombokensis	N. malayanus		N. malhaensis		N. meteori	N. steatiticus		N. stefanovi		N. monocellatus
	HT	range	n	HT	range	n	range	n	HT	range	n	range	n	range	n
SL (in mm)	165	130–158	9	93	76–199	44	117–135	4	102	113–162	6	29–198	45	36–154	67
Meristic Characters
Dorsal-fin rays	92	90–93	9	91	90–96	23	99–103	4	91	88–94	6	89–95	39	93–99	65
Caudal-fin rays	8	8–8	6	7	8–8	23	8–8	4	7	8–8	5	8–8	28	8–8	61
Anal-fin rays	77	72–76	9	72	74–79	20	78–82	4	75	73–77	6	73–78	40	78–83	66
Pectoral-fin rays	28	24–27	9	29	26–28	13	30–30	4	27	24–24	6	24–26	31	24–27	49
Precaudal vertebrae	13	12–12	9	13	12–13	23	13–13	4	13	12–12	5	12–12	48	12–13	67
Total vertebrae	56	54–56	9	53	54–57	23	57–59	4	53	53–57	5	52–56	40	54–58	67
Pseudobranchial filaments	2	3–4	9	3	2–4	35	3–4	4	3	2–3	6	2–6	29	4–6	60
Dorsal-fin origin above vertebra nr.	6	4–5	9	5	5–6	24	2–3	4	5	4–5	5	4–5	47	5–6	66
Anal-fin origin below dorsal fin ray nr.	21	18–21	9	21	17–21	24	23–25	4	20	19–21	5	17–21	44	17–21	66
Anal-fin origin below vertebra nr.	15	15–15	9	16	15–16	24	15–15	4	15	14–15	5	14–16	46	14–15	66
Developed gill rakers	10	11–13	9	7	8–11	43	12–13	4	6	11–14	6	10–13	44	13–15	63
Total gillrakers	19	20–22	9	15	17–20	19	21–22	4	12	21–24	6	18–24	30	19–24	63
Morphometric characters
in % SL
Head length	22	25–28	9	23	21–28	43	21–22	4	22	28–31	6	23–27	45	21–24	67
Body depth at anal-fin origin	20	18–21	9	19	17–20	21	17–19	4	19	17–20	6	15–22	45	15–19	64
Upper-jaw length	12	12–12	9	9.7	11–12	20	11–11	2	9.8	12–14	5	11–14	37	10–13	61
Orbit length	4.5	5.3–5.9	9	5.2	4.2–5.6	36	4.1–4.9	4	4.9	4.8–5.2	6	5.4–6.9	37	4.9–7.0	61
Preanal distance	41	38–42	8	44	39–47	20	36–40	4	45	40–46	6	38–45	38	36–43	64
Predorsal distance	25	25–27	8	26	24–29	42	20–21	4	24	24–28	6	24–28	38	20–27	64
Pelvic-fin to anal-fin origin distance	25	22–27	9	30	22–30	19	21–27	4	27	24–29	5	21–29	37	20–27	62
Pelvic-fin length	14	14–17	8	13	14–20	35	13–13	4	11	14–15	6	14–20	38	17–23	62
Gill-filament length	1.9	3.9–4.9	9	2.2	1.3–3.8	43	1.6–1.9	4	2.8	4.4–5.9	5	1.4–3.7	42	1.4–2.0	62
Postorbital distance	13	15–18	9	14	13–17	28	13	1	14	17–19	4	14–17	37	11–14	16
in % HL
Upper-jaw length	54	43–48	9	42	44–52	21	50–51	2	44	43–47	5	41–55	37	49–56	61
Orbit length	21	20–24	9	23	16–23	37	19–23	4	22	16–18	6	22–27	40	22–30	61
Gill-filament length	8.8	15–19	9	9.4	5.2–14	44	7.5–8.9	4	13	15–19	5	5.4–16	45	6.2–9.0	62
Postorbital distance	58	59–65	9	62	56–66	29	60	1	63	60–68	4	57–66	37	48–63	16
Central ocellus characters
Snout tip to ocellus spot distance % SL	46	49–51	9	43	43–52	42	42–46	4	39	46–51	6	46–56	44	41–51	67
Dorsal-fin rays covered by spot	7	6–8	9	14	6–10	20	13	1	9	7–10	6	8–12	47	6–7	9
First dorsal fin ray in spot	22	24–30	9	18	20–27	20	23	1	17	21–27	6	22–30	47	22–28	9
Central-most ray in spot	25	27–34	9	25	24–30	20	29	1	21	25–31	6	26–34	47	25–31	9
Vertical-scale rows covered by spot	0	0–1	9	0	0–0	20	1	1	0	0–0	4	0–4	38	0–0	9
Otolith characters
in % SL
Otolith length	4.8	4.8–5.0	4	4.8	5.1–5.6	6	5.2	1	4.6	5.0–5.2	2	4.6–5.2	5	5.0–5.8	8
Otolith height	2.8	3.0–3.3	4	3.1	3.0–3.4	6	3.3	1	2.6	3.0–3.4	2	2.9–3.3	5	2.9–3.7	8
Sulcus length	3.8	3.4–3.7	4	3.2	3.3–4.1	6	3.8	1	–	3.6–3.7	2	3.4–4.1	5	4.0–4.7	8
Ostium length	2.6	2.3–2.5	4	1.9	2.1–2.7	6	2.5	1	–	2.3–2.5	2	2.3–2.6	5	2.5–2.9	8
Ostium height	0.71	0.73–0.89	4	0.84	0.77–0.94	6	0.80	1	–	0.77–0.89	2	0.74–1.05	5	0.70–0.89	8
in % sulcus length
Ostium length	68	67–68	4	59	61–72	7	67	1	–	65–67	2	63–70	6	59–64	8
Ostium height	19	21–26	4	26	21–25	7	21	1	–	21–25	2	20–29	6	18–22	8
in % ostium length
Ostium height	27	31–39	4	44	32–38	7	32	1	–	31–38	2	30–41	6	28–34	8