(Richardson, 1846)
1. Distinctive characteristics of early developmental stages
(a) Eggs and Larvae
No information from the mangroves.
(b) Early juveniles (Description based on over 12.5 mm T.L. specimens)
Cynoglossus puncticeps 1
Cynoglossus puncticeps 2 (Juvenile measuring 64 mm)
The body is tongue-like (flat and elongated). Dorsal, caudal and anal fins are confluent. The dorsal fin is yet to move forward up to the snout at this stage. The snout is rounded. Lateral lines are yet to develop in the eyed side (in juveniles and adults, two lateral lines are present on the eyed side and not on the blind side). The paired eyes on the eyed side are yet to move towards the left side of the body, even in juveniles. (In adults, eyes are located on the left side of the body). The preoperculum is hidden beneath the skin.
Distinct brown blotches which look like bands (7-9) on the eyed side have not yet become more irregular at this stage (in juveniles and adults the distinct blotches are irregular).
The proportionate heights of the dorsal, anal and caudal fins to the breadth of the body are relatively more in early juveniles when compared to those in adults. The dark brown pigmentation in the bands extends up to about half the height of the dorsal and anal fins (not so in adults). The base of the dorsal and anal fins possess dark pigmentation which runs from the anterior to the posterior end of the body in the eyed side. Pectoral fins are absent. Only one pelvic fin is present (not in pairs) on the left portion of the eyed side (prior to the anal fin origin).
2. Distinguishing characteristics of early developmental stages in similar species occurring in the mangroves
(a) Early juveniles of Cynoglossus lida
Pigmented blotches are absent (present in C. puncticeps ).
(b) Juveniles of Praplagusia bilineata
The mouth is fringed with tentacles (tentacles are absent in C. puncticeps ).
(c) Juveniles of Pseudorhombus arsius (family Bothidae)
The body is flat and almost oval in shape with distinct and prominent caudal fins (the body is flat and elongated with relatively small caudal fins confluent with the dorsal and anal fins in the case of C. puncticeps ). Pectoral fins are present (absent in C. puncticeps ). Pelvic fins are present on both the eyed and blind sides (only one pelvic fin is present and located at the left portion of the eyed side in the case of C. puncticeps ). The margin of the preoperculum is free (in C. puncticeps, the preoperculum is hidden beneath the skin).
(d) Juveniles of Euryglossa orientalis and Aseraggodes cyaneus (family Soleidae).
Pectoral fins are well developed (Absent in C. puncticeps ).
(e) Post larvae of Solea elongata (Soleidae family)
Solea elongata 1
Pectoral fins are present. Two lateral lines are present on the ocular side, almost parallel to each other (in adults the upper lateral line borders the base of dorsal fin). Probably the only species/genus among Soleidae to possess two lateral lines on the eyed side in addition to prominent pectoral fins. (vide Fischer and Bianchi, 1984 and Munro, 1955 for further details). (In the case of C. punticeps two lateral lines are present in juveniles and adults but not in larval and early juvenile stages. In addition, the larvae, juveniles and adults of C. puncticeps do not possess any pectoral fins.)
3. Distinguishing characteristics of juveniles in similar species occurring in the coastal waters
(a) Zebrias spp.
Bands/cross bars are regular (only moderately regular in early juveniles and irregular in juveniles and adults of C. puncticeps ).
(b) Aesopia cornuta
Narrow bands are present. The first ray of the dorsal fin is free and enlarged (not so in C. puncticeps ).
4. Salient biological characteristics (after Fischer and Bianchi, 1984 and Jeyaseelan, 1981)
It grows to a maximum size of 180 mm in total length in coastal waters. In mangroves, it dwells until 120 mm in size. It feeds on benthic and demersal organisms in coastal waters. In the mangroves the juveniles feed on gammarids, detritus, fish scales, benthic copepods, planktonic copepods and tanaids in descending order of importance. It is distributed throughout the coasts of India, Malaysia, Indonesia, the Philippines and up to the northwest coast of Australia.
5. Salient ecological information
The juveniles of this bottom dwelling species use the mangroves as a nursery ground. The adults occur up to a depth of 140 m on the Continental shelf. The juveniles occur even in high turbid waters and prefer the muddy bottom. In mangroves, the juveniles of this species occur in mixo-oligohaline to mixo-euhaline conditions of water salinity (i.e. from near fresh water level to sea water salinity level).
6. Capture fisheries
Caught by drag-nets in the mangroves and by bottom trawls in the coastal waters.