title: Early development of New Zealand hapuku Polyprion oxygeneios eggs and larvae.
abstract: This study describes for the first time the normal development of New Zealand hapuku Polyprion oxygeneios embryos and larvae reared from fertilization to 11 days post-hatch (dph) at a constant temperature. Fertilized eggs were obtained from natural spawnings from communally reared captive wild broodstock. Eggs averaged 2 mm in diameter and had single or multiple oil globules. Embryos developed following the main fish embryological stages and required an average of 1859·50 degree hours post-fertilization (dhpf) to hatch. The newly hatched larvae (4·86 mm mean total length, L(T) ) were undifferentiated, with unpigmented eyes, a single and simple alimentary tube and a finfold that covered the entire body. Larvae relied on the energy from the yolk-sac reserves until 11 dph (7·33 mm mean L(T) ), when yolk-sac reabsorption was almost completed. Some of the major developmental stages from hatching to yolk-sac reabsorption were eye pigmentation (5 dph), upper jaw formation (7 dph), lower jaw formation (8 dph) and mouth opening (8-9 dph). By 9 dph, the digestive system consisted of pancreas, liver, primordial stomach, anterior and posterior gut; therefore, P. oxygeneios larvae would be capable of feeding on live prey. The developmental, morphological and histological data described constitutes essential baseline information on P. oxygeneios biology and normal development.
authors.affiliation: National Institute of Water and Atmospheric Research Ltd, Private Bag 14-901, Wellington 6241, New Zealand.
authors.forename: S A
authors.initials: SA
authors.lastname: Anderson
authors.forename: I
authors.initials: I
authors.lastname: Salinas
authors.forename: S P
authors.initials: SP
authors.lastname: Walker
authors.forename: Y
authors.initials: Y
authors.lastname: Gublin
authors.forename: S
authors.initials: S
authors.lastname: Pether
authors.forename: Y Y
authors.initials: YY
authors.lastname: Kohn
authors.forename: J E
authors.initials: JE
authors.lastname: Symonds
mesh_terms: D000400:Air Sacs / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development; D000818:Animals; D004625:Embryo, Nonmammalian / Q000033:anatomy & histology; D047108:Embryonic Development; D005123:Eye / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development; D007814:Larva / Q000033:anatomy & histology / Q000254:growth & development; D009055:Mouth / Q000033:anatomy & histology / Q000196:embryology / Q000254:growth & development; D009520:New Zealand; D010063:Ovum / Q000166:cytology / Q000254:growth & development*; D010473:Perciformes / Q000196:embryology* / Q000254:growth & development; D012098:Reproduction