Key to the species of the genus Parascombrops
1 Pelvic-fin spine, second spine of D1 and second spine of anal fin serrated........................................ 2
- Only pelvic-fin spine serrated........................................................................... 4
2 Spine of D2 serrated; pseudobranchials 16–21; no ridges on preopercle; first anal-fin pterygiophore broad, hollow; otolith compressed (OL:OH = 1.35–1.40).......................................................... P. serratospinosus
- Spine of D2 smooth; pseudobranchials 24–31; 1–3 ridges on preopercle; first anal-fin pterygiophore pointed, not hollow; oto- lith elongate (OL:OH = 1.70–1.80)....................................................................... 3
3 Orbit 8.6–10.9% SL; HL 31.3–35.2% SL; predorsal length 33.3–39.8% SL; pseudobranchials 24–28; OL:OH = 1.75–1.80; otolith rim considerably higher mid-dorsal than postdorsal............................................. P. spinosus
- Orbit 10.8–12.8% SL; HL 37.0–39.8% SL; predorsal length 39.5–42.2% SL; pseudobranchials 29–31; OL:OH = 1.70; post- dorsal angle strong, about as high as mid-dorsal rim........................................... P. mochizukii n. sp.
4 Dense, elongate tooth patch on tongue; large diamond-shaped vomerine tooth patch with granular teeth only................................................................................................... P. glossodon n. sp.
- No tooth patch on tongue; vomerine tooth patch V-shaped or triangular, often with long teeth at rear.................. 5
5 Dentary without lateral fangs............................................................. P. parvidens n. sp.
- Dentary with 2–4 lateral fangs.......................................................................... 6
6 Anal fin with III spines and 6 soft rays (> 65 mm SL); first anal-fin pterygiophore broad, hollow, with forward bent and wid- ened tip....................................................................................... P. analis
- Anal fin always with II spines and 7 soft rays; first anal-fin pterygiophore broad or slender, hollow or pointed, without forward bent or widened tip....................................................................................7
7 Pectoral fin reaching anterior insertion of anal fin, 27–31% SL; gill rakers 19–25......................... P. pellucidus
- Pectoral fin not reaching anterior insertion of anal fin, 20–27% SL; gill rakers 11–18................................8
8 Snout profile blunt (Fig. 7D, M); maximal body height 30–34% SL otolith compressed (OL:OH = 1.5–1.6) (not known for P. madagascariensis).................................................................................... 9
- Snout profile rounded (Fig. 7D, M) or pointed (Fig. 7F, J) maximal body height 21–29% SL; otoliths moderately elongate to elongate (OL:OH = 1.65–2.1)......................................................................... 10
9 Vomerine tooth patch triangular, with one continuous row of long teeth posteriorly (Fig. 9D); palatine and ectopterygoid tooth bands narrow with 1–2 rows of denticles (Fig. 9D); preopercle always without spike; first anal-fin pterygiophore long, slightly curved toward tip; otolith not known................................................. P. madagascariensis n. sp.
- Vomerine tooth patch V-shaped, anteriorly with reduced dentition, posteriorly 1–2 long teeth (Fig. 10F); ectopterygoid tooth band wide with 3–6 rows of denticles, palatine tooth band narrow with 1–2 rows of denticles (Fig. 10F); preopercle usually with spike (in 80% of specimens examined); first anal-fin pterygiophore straight; otolith rims intensely crenulated on rear part..................................................................................... P. yamanouei n. sp.
10 First anal-fin pterygiophore hollow, with broad tip; preopercle without ridges (Fig. 11E)............................ 11
- First anal-fin pterygiophore thin, not hollow; preopercle with 1–3 ridges (Fig. 11D)............................... 12
11 Head slender with tapering snout profile; snout 87–113 % of orbital diameter; vomer without or with few granular teeth anteriorly and 2–4 long teeth posteriorly; dentition on ectopterygoid widened with 3–4 rows versus only 1 row on palatine (Fig. 9F)..................................................................................... P. nakayamai n. sp.
- Head stout; snout 68–90 % of orbital diameter; vomer with 1 to 3 rows granular teeth anteriorly and 1 to 3 long teeth posteriorly; 1–2 rows of denticles on palatine and on narrow ectopterygoid (Fig. 10B)........................ P. philippinensis
12 Dorsal head profile slightly convex (Fig. 17); otoliths moderately elongate (OL:OH = 1.65–1.85), with distinct mediodorsal angle; pseudobranchials 26–38 (SL 66–183 mm), down to 22 in smallest specimen (SL 53 mm); first soft anal-fin ray branched at tip; large fish attaining sizes to 183 mm SL...................................................... P. argyreus
- Dorsal head profile strongly convex (Fig. 22); otoliths elongate (OL:OH = 1.90–2.10), dorsally flat; pseudobranchials 19–25; first soft anal-fin ray not branched at tip (Fig. 6G); fishes not exceeding 90 mm SL....................... P. ohei n. sp.