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3 RESULTS

at a neritic station southeast of Lanzarote in a depth of 13 – 41 m at daytime. In winter larvae were found southeast from Fuerteventura at a depth of 30 – 123 m during the night. Bothus podas was caught at a mesopelagic station southeast of Fuerteventura at 440 – 665 m depth during the late daytime. In spring specimens were found at a neritic station southwest of Gran Canaria at a depth of 33 – 53 m during the night and in the day at mesopelagic stations southeast of Fuerteventura in a depth range of 382 – 511 m as well as southwest of Gran Canaria at a depth of 480 – 694 m. In late spring some specimens were caught at the epipelagic station far north of Gran Canaria at a depth of 42 – 47 m during the night.

¬ TETRAODONTIFORMES All larvae are pelagic and most have a direct development. Only few characteristics are uniform among the Tetraodontiformes and some other are also found in other orders, e.g. the late formation of the caudal fin and scale specializations, which may form very early, as well as the dermal sac is not only found within this order. The large head with the large eyes and the small mouth, the presence of the gas bladder, the coiled and massive gut and the low number of myomeres are characteristic for this order. The pelvic fins are reduced or lacking. In the suborder Tetraodontoidei larvae are sheltered in a vesicular sac. In comparison to the rest of the body is the tail small and laterally compressed. Larvae are strongly pigmented. Except for the molids no dermal spines develop and the tail does not form. The larvae of the suborder Balistoidei are mainly deep and wide bodied. If the tail seems to be reduced, it never had developed. Larvae are moderately to strongly pigmented. In both suborders the transformation takes place at a small larval size and species have a long, not specialised juvenile stage.

-- Reference: ABOUSSOUAN and LEIS (1984); LEIS (1984);

BALISTOIDEI > Balistidae Larvae hatch at 1.5 – 2 mm NL and no jaws or eye pigmentation is developed.The body is less pigmented and cylindrical with a slightly small lateral compression in shape. With development the body deepens fast and is almost round in cross section at the level of the trunk, but the tail remains compressed. Only in newly hatched larvae a kind of inflated sack shelters the trunk, but disappears soon and close to the flexion, the gill opening reduces till a pore remains. In Balistidae the spines of the dorsal fins are first to form, followed by a simultaneously formation of dorsal rays, the anal fin and the pectoral fins. The caudal fin is the last developing. The fin formation is completed at around 5 – 6 mm SL. The pelvic fins are absent, but a modified pelvic spine develops. Prominent in this family is the elongation of the first spine, which can be armed with hooks during preflexion stage. During preflexion spines develop on preoperculum and disappears shortly before dermal spines develop on the jowl, cleithrum, on the forehead and laterally on the gut, where they spread all over the entire body by midflexion.This spinulated remain till into the juvenile stage, but do not transform into the prominent specialised scales in adults. Pigmentation concentrates on the brain and gut. In preflexion larvae a series of melanophores develops along the ventral midline from posteriorly of the anus to the tail, where bands may develop. The spinous dorsal fin membrane is strongly pigmented and from there pigments spread out all over the trunk with further development.

-- Reference: ABOUSSOUAN and LEIS (1984); LYCZKOWSKI-SHULTZ and INGRAM (2006);

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Inf. Téc. Inst. Canario Cienc. Mar. n°13

Spatial and seasonal patterns in species composition of fish larvae in the Canary Islands  

Technical report consisting on a comprehensive annotated larvae taxa list with the most important taxonomic characters of this region

Spatial and seasonal patterns in species composition of fish larvae in the Canary Islands  

Technical report consisting on a comprehensive annotated larvae taxa list with the most important taxonomic characters of this region

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