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SPATIAL AND SEASONAL PATTERNS IN SPECIES COMPOSITION AND OCCURRENCE OF FISH LARVAE IN THE AREA OF THE CANARY ISLANDS, EASTERN CENTRAL ATLANTIC

-- Reference material: 1 specimen; 11/97: S5 (P44296);

-- Distribution: Only one specimen was found at an epipelagic station south of Fuerteventura at a depth of about 40 m at the break of dawn in autumn.

Carangidae The family consists of four subfamilies. But larvae hatches at a length of 1.3 – 4.3 mm having a large yolk sac but underdeveloped mouth, no pectoral fin buds, and no eye pigmentation. The gut is initially straight and reaches up to 50 – 70 % of BL, but coils with development without changing the preanal length. Most early larvae are slender with a large head and increase their body depth with growth. On the head ridges and spines form out, where the two rows of spines at the preoperculum are prominent, with the larger spines developing along the posteriorly margin of the preoperculum. The largest spine hereby is situated at the angle of the preopercle, which is also the first to form in early larvae. The number of the spines is variable and increase during early development and gets reduced in early juvenile stage. Just shortly towards the juvenile stage, the remaining preopercular spines get completely overgrown by bones and tissue. Other spination occurs at the supracleithrum and the posttemporal bones until flexion stage, but no spines form at interoperculum and suboperculum.The often serrated supraoccipital ridge forms early in preflexion larvae and remains to late transformation stage, where it is also overgrown by bones and tissue. The frontal supraocular ridge may develop spines. The fin formation starts with the caudal fin rays in late preflexion stage, followed by the pectoral fins and soft rays of dorsal and anal fin. The spinous dorsal fin forms next, while the pelvic fins develop last. At the anteriorly margin of the first dorsal fin an antrorse spine is developed, but covered by skin. Pigmentation is very variable and ranges from light to almost complete, but melanophores concentrate at dorsum, the gas bladder, the gut, along the lateral midline, along the ventrally margin of the tail and laterally on the caudal fin base. The pigmentation gets more intense during postflexion stage, with the countershading initiate and vertical bars begin to form.The development is gradually and direct. No sudden metamorphose happens.The number of myomeres ranges at 23 – 26 or 27. The first two spines of the anal fin are separated from the rest and a distinctive gap in most species is present.

-- Reference: LAROCHE, SMITH-VANIZ and RICHARDSON (1984); WATSON et al. (1996);

•  Campogramma glaycos Meristics: Dorsal spines + rays:

VI – VII + I + 26 – 28

Anal spines + rays:

II + I + 23 – 25

-- Morphology: The mouth is large, extending the level of the eye. The dorsal fin base is shorter than the anal fin base. The length of pectoral fin rays is extending the pelvic fins rays.The separated first two spines were clearly visible in the studied specimens (Figure 61).

-- Reference: SMITH-VANIZ (1986);

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

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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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