. Bulletin of the Natural History Museum (Zoology). Fig. 8 Erenna laciniata. A. upper and B, lower views of mature nectophore. Scale 5 mm. On each side there was a thickened flap that lay ventrally and was directed toward the mid-line. On smaller, younger nectophores i Fiy. 9) the thrust block consisted of two small protuberances sepa- rated by a U-shaped indentation. The main ridge system was well delineated, especially in the younger nectophores (Fig. 9). It consisted of pairs of infra- and apico- lateral ridges, which united close to the lateral apices of the axial wings; and a short pair o
. Bulletin of the Natural History Museum (Zoology). Fig. 8 Erenna laciniata. A. upper and B, lower views of mature nectophore. Scale 5 mm. On each side there was a thickened flap that lay ventrally and was directed toward the mid-line. On smaller, younger nectophores i Fiy. 9) the thrust block consisted of two small protuberances sepa- rated by a U-shaped indentation. The main ridge system was well delineated, especially in the younger nectophores (Fig. 9). It consisted of pairs of infra- and apico- lateral ridges, which united close to the lateral apices of the axial wings; and a short pair of vertical laterals connecting them (Fig. 8), although, in younger nectophores, the junction with the apico-laterals was indistinct (Fig. 9). The infra-laterals ended, basally, on either side of the ostium. The apico-laterals remain prominent until just above ostial level. In younger nectophores, close to the ostium, the apico- laterals gave rise to three very vague, but broad branches (Fig. 9A). However, in mature nectophores only after staining could two very vague ridges be discerned (Fig. 8A). These would be virtually impossible to see in damaged or poorly preserved material. No obvious mouth plate, and ostial opening basal. Prominent protuberances on each side of the ostium which bore strips of distinctive epidermal cells, and another triangular patch in mid-line on dorsal side of the ostium. In addition, a relatively large patch of such cells was present on each side of the nectophore, at about the mid-height of, and immediately basal to, the vertical lateral ridges (Figs 8A, 9A). All these patches are believed to be sites of bio- luminescence. T-shaped nectosac with a distinct muscle-free zone at its apex. Short pallial canal, originating at the base of the thrust block, with a long pedicular canal, which on reaching the nectosac gave rise to the four, straight, radial canals. In the younger nectophores there were obvious signs of thickening of the lateral radial canals
Size: 2273px × 1100px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bhlconsortium, book, bookcollectionbiodiversity, bookleafnumber70
