Johnius Bloch 1793
Creators: name: Hanafi, Norhafiz
name: Chen, Meng-Hsien
name: Chang, Chih-Wei
name: Chao, Ning Labbish
name: Seah, Ying Giat
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Perciformes
Sciaenidae
Johnius

description: Key to the species of Johnius in the East Malaysian waters
1a. Chin with barbel............................................................ J. amblycephalus (Bleeker, 1855)
1b. Chin without barbel................................................................................... 2
2a. Upper jaw and inner row of lower jaw teeth enlarged, conical.................................................. 3
2b. Upper jaw and inner row of lower jaw teeth uniform, molariform............................................... 4
3a. Snout rounded............................................................... J. plagiostoma (Bleeker, 1850)
3b. Snout pointed................................................................. J. borneensis (Bleeker, 1851)
4a. Body dark pigmented; lower fins black............................................... J. belangerii (Cuvier, 1830)
4b. Body silvery to light yellow; lower fins pale................................................................ 5
5a. Scales moderately small, upper scale rows 7–11, lower scale rows 11–17......................................... 6
5b. Scales large, upper scale rows 4–7, lower scale rows 6–14..................................................... 7
6a. Gill rakers on the 1 st arch slender and long, 9–12 gill rakers on the lower limb of 1 st arch with length longer than half of gill filaments length.................................................................. J. coitor (Hamilton, 1822)
6b. Gill rakers on the 1 st arch stiff and short, 7–9 gill rakers on lower limb of 1 st arch with length shorter than half of gill filaments length........................................................................ J. weberi (Hardenberg, 1936)
7a. Lower jaw with inner row of molariform teeth posteriorly............................. J. macrorhynus (Mohan, 1976)
7b. Lower jaw teeth all conical, uniform in size................................................................ 8
8a. Total outer gill rakers of 1st arch 16–18................................................ J. carouna (Cuvier, 1830)
8b. Total outer gill rakers of 1st arch 13–15.................................................................... 9
9a. Total outer gill rakers of 1st arch (mode 12) with lower limb of 8–10 (mode 8), total scale rows 8–11 (mode 8) respectively................................................................................ J. trewavasae Sasaki, 1992
9b. Total outer gill rakers of 1st arch (mode 14) with lower limb 8–11 (mode 9–10), total scale rows 9–20 (mode 15) respectively. .................................................................................................. 10
10a. Gill rakers of outer gill rakers of 1st arch at the upper limb, 4–5 (mode 4) and lower limb 9–11 (mode 10) respectively.................................................................................... J. heterolepis Bleeker, 1873
10b. Gill rakers of outer gill rakers of 1st arch at the upper limb, 4–6 (mode 5) and lower limb 8–10 (mode 9) respectively..................................................................................... J. sasakii Hanafi et al. 2022
description: Published as part of Hanafi, Norhafiz, Chen, Meng-Hsien, Chang, Chih-Wei, Chao, Ning Labbish & Seah, Ying Giat, 2024, Taxonomic review of the genus Johnius (Perciformes: Sciaenidae) from East Malaysian waters, with comments on newly recorded Johnius species, pp. 85-117 in Zootaxa 5550 (1) on page 95, DOI: 10.11646/zootaxa.5550.1.11, http://zenodo.org/record/14388193