dc.description.abstract | Nomorhamphus sp. is endemic ornamental fish from Lindu, Sulawesi Tengah. Nomorhamphus sp. is viviparous fish and it has unique body shape and color. Several of Nomorhamphus species have been sold as ornamental fish commodities. But, production of Nomorhamphus still relies from wild catches. Overfishing will threat Nomorhamphus sp. sustainability. Other threats are anthropogenic, agricultural waste and invasive fish in Lindu. Aquaculture can be potential solution for sustainable Nomorhamphus sp. production. Aquaculture begins from domestication. Domestication is an adaptation of fish from nature to a controlled environment. This process requires basic biology information of fish life. Biological information of Nomorhamphus sp. used to determine step of aquaculture management, conservation, and development. Critical point of fish life is larval stage. Information of larval stage can obtain from morphogenesis and biometric information on early life of Nomorhamphus sp.
This study aimed to study of morphogenesis and biometric on early life stage as basic information of Nomorhamphus sp. culture. This study contained morphometric and meristic characters, mouth width, morphogenesis and feeding behavior. Morphometric was measured using caliper and analyzed based on standard length ratio. Meristic was measured using microscope to count fins rays. Mouth width was identified for feed size. Mouth width was measured based on 90° angle form of upper jaw. Morphogenesis was observed by development and growth of fish body on larval and juvenile stages. Feeding behavior was observed based on body shape and lower jaw length.
Result showed that new born Nomorhamphus sp. larva had 13,57 – 14,42 mm standard length, 15-days-old had 16,53 – 17,55 mm standard length, 25-days-old had 16,87 - 18,38 mm standard length and 30-days-old had 20,4 – 23,32 mm standard length. Morphometric characters ratio showed growth of body length and fin length. morphometric characters ratio showed a transition between larvae and juveniles on day 15 and day 25. Larvae had proportional body shape on 30-days-old. Juvenile body was growth in between pectoral fin and anal fin. Fin rays meristic characters showed no difference between larva and juvenile stage. Fin rays meristic were 14-15 anal fin rays (A.14-15), 11 dorsal fin rays (D.11), 13 pectoral fin rays (P.13), dan 6 ventral fin rays (V.6). New born Nomorhamphus sp had cream body color, yellow jaw, and transparent silver color on their belly. Swim bladder was developed after birth. Nasal barbel were found on their head. Larvae had cream color, silver belly and orange pattern ventral and caudal fins on 15-days-old. Then, yellow jaw was faded. 25-days-old had cream and silver color body. Their body morphology was like adult-age. Juvenile stage has started 25-days-old. Male’s Andropodium was developed as secondary sexual dimorphism on 25-days-old. Sexual dichromatism was identified by brighter orange strip kaudal fin in males. 30-days-old had similar character with 25-days-old. Newborn larvae are motionless at bottom of water and try to swim to the surface because their swim bladder was not filled yet. Newborn can moved after their swim bladder were filled. Nomorhamphus sp. can find their feed in water column and bottom. | id |