Neobythites steatiticus, Alcock, 1894

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 : 202

Key to the steatiticus species group

1 Anterior gill arch with 6–7 long rakers; anal fin without dark margin or band..................................... 2

- Anterior gill arch with 8–15 long rakers; anal fin with or without dark margin or band.............................. 3

2 Ocellus short, placed above anus with ocellus spot covering 9 dorsal-fin rays; longest gill filament 13.0% HL....................................................................... N. meteori (off Sokotra Island, NW Indian Ocean)

- Ocellus long, placed above anterior part of anal fin with ocellus spot covering 14 dorsal-fin rays; longest gill filament 9.4% HL............................................................ N. lombokensis (off Lombok, E Indian Ocean)

4 Vertical, dark bar below ocellus spot; dorsal and anal fins without dark margin or band, dorsal-fin rays 99–103, dorsal-fin origin above vertebrae number 2–3, anal-fin origin below dorsal-fin ray number 23–25............................................................................................ N. malhaensis (Saya de Malha Bank, W Indian Ocean)

- None to a few indistinct, vertical, dark bars on body; dorsal and/or anal fin with dark margin or band, dorsal-fin rays 88–99, dorsal-fin origin above vertebrae number 4–6, anal-fin origin below dorsal-fin ray number 17–21..................... 4

4 Median part of anal fin dark, and distal and proximal parts light; head length 28–31% SL; longest gill filament 4.4–5.9% SL.............................................................. N. steatiticus (Bay of Bengal, NE Indian Ocean)

- Distal part of dorsal and anal fins dark and proximal part light; head length 21–28% SL; longest gill filament 1.3–4.9% SL.. ................................................................................................... 5

5 Developed gill rakers 8–11 (mostly 9 or 10); orbit length 4.2–5.6% SL and 37–46% upper-jaw length; precaudal vertebrae 13 (rarely 12).......................................................................................... 6

- Developed gill rakers 10–15 (mostly 11–15); orbit length 4.9–7.0% SL and 42–59% times in upper-jaw length; precaudal vertebrae 12 (rarely 13)................................................................................ 7

6 Preopercular spine indistinct or a flat process, upper-jaw length 44–52% HL, ostium height 0.77–0.93% SL, 21–25% sulcus length and 32–38% ostium length.................................. N. malayanus ( Indonesia, Philippines, Vanuatu)

- Preopercular spine very short but distinct, upper-jaw length 54% HL, ostium height 0.65% SL, 17% sulcus length and 25% ostium length................................................................. N. pako n. sp. (Solomon Sea)

7 Dorsal-fin rays 93–99, anal-fin rays 78–83, developed gill rakers 13–15, head length 21–24% SL, postorbital distance 11–14% SL, sulcus length 4.0–4.7% SL and ostium length 59–64% sulcus length..................................................................................... N. monocellatus ( Honduras to off Bahia, E Brazil, W and SW Atlantic)

- Dorsal-fin rays 89–95, anal-fin rays 72–78, developed gill rakers 10–13, head length 23–28% SL, postorbital distance 14–18% SL, sulcus length 3.4–4.1% SL, and ostium length 63–70% sulcus length........................................ 8

8 Longest gill filaments 1.4–3.7% SL; dorsal-fin rays in ocellus spot 8–12.............................................................................................. N. stefanovi (Red Sea and Gulf of Aden, NW Indian Ocean)

- Longest gill filaments 3.9–4.9% SL; dorsal-fin rays in ocellus spot 6–8....................................................................................... N. gloriae (Arabian Gulf and inner Gulf of Oman, NW Indian Ocean)