Günther
1. Distinctive characters of early developmental stages
(a) Eggs and larvae
Not reported from mangroves.
(b) Early Juvenile (Based on 26 mm length specimen)
Zenarchopterus brevirostris 1
Dorsal fin with 10-11 rays and anal fin with 13-14 rays. Anal fin originates behind the dorsal origin; pelvic fin nearer to caudal base than to head. Caudal fin round/truncate. Lower jaw protruded into a beak and about 5 times the length of upper jaw. The body possesses six longitudinal rows of pigments.
2. Distinguishing characters of early developmental stages in similar species occurring in the mangroves
(a) Larvae and early juveniles of Hyporhamphus (Hyporhamphus) limbatus
Only 3 longitudinal rows of pigments.
3. Salient ecological information
It occurs in the mangroves of Singapore and Thailand. Early juveniles occur in mangrove waterways of Thailand during 'wet season' (June - August).