Johnius plagiostoma (Bleeker, 1849)

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, Zootaxa 5550 (1), pp. 85-117 : 106

Johnius plagiostoma (Bleeker, 1849)

(Common name: Big-eye croaker)

( Fig. 12 , Table 7 )

Corvina plagiostoma Bleeker, 1849: 10 (type locality: Madura Straits near Surabaya and Kammal, Java, Indonesia.) Syntypes: RMNH 5984 (2)

Johnius plagiostoma (Bleeker, 1850) : Sasaki, 1999: 276; Sasaki, 2000: 621; Sasaki, 2001: 3157; Mohamad Faisal, 2009: 98; Atan et al., 2010: 195

Material examined. Non-types: NMMB-P37100 (3, 90.97 to 95.43 mm SL), Sarikei , Sarawak, Malaysia, 14 March 2017 ; NMMB-P37101 (10, 80.93 to 103.56 mm SL), Goebilt , Sarawak, Malaysia, 17 March 2017 ; NMMB-P31389 (2, 87.72 to 103.64 mm SL), Muar , Johor, Malaysia, 19 March 2019 : NMMB-P21525 (3, 81.16 to 94.65 mm SL), Tanjung Piandang , Perak, Malaysia, 6 June 2014 ; NMMB-P26489 (3, 91.15 to 110.23 mm SL), Kuala Kurau , Perak, Malaysia, 1 June 2014 ; NMMB-P26500 (3, 87.39 to 105.49 mm SL), Kuala Kurau , Perak, Malaysia, 23 November 2019 .

Diagnosis. A species of Johnius with the following combination of characters: snout rounded, never pointed; mouth large, strongly oblique; large eye, 22 to 32% of head length; gill rakers long, slender, equal or slightly shorter than length of gill filaments at angle of arch, 15 on lower limb of first gill arch; second anal spine length long, stiff, about 24 to 40% of HL; and scales moderately small, 8 scale rows above lateral line.

Distribution. Eastern Indian Ocean, western Pacific: Bangladesh and Myanmar east to Java, Borneo and Vietnam.

Remarks. Johnius plagiostoma can be easily differentiated from the rest of other Johnius species in the East Malaysian waters by the oblique mouth and obviously large eye. Johnius plagiostoma is abundant and was available collected only from Sarawak states, specifically in Goebilt and Sarikei collection sites, which mainly segregated in the large mouth and delta riverine system. This might be due to the ecological factor of freshwater and marine waters mainly mixed up, suitable for the species habitat and availability of food resources.

Figures

FIGURE 12. Photographs of the comparative materials. Johnius plagiostoma: NMMB-P 37101, non-type, 95.43 mm SL, Goebilt fish landing port, Sarawak, Malaysia, 17 March 2017.