Rhynchoteuthion larvae from New Zealand coastal waters (cephalopoda: ommastrephidae)
Rhynchoteuthion stage ommastrephid larvae from New Zealand coastal waters were measured and the developing proboscis studied by scanning electron microscope. Many specimens show some retraction of the head and posterior mantle. Mantle shape is frequently cylindrical anteriorly and slightly expanded...
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| Format: | Article in Journal/Newspaper |
| Language: | English |
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Laboratoire Arago
1986
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| Online Access: | https://oceanrep.geomar.de/id/eprint/34256/ https://oceanrep.geomar.de/id/eprint/34256/1/1129.pdf |
| Summary: | Rhynchoteuthion stage ommastrephid larvae from New Zealand coastal waters were measured and the developing proboscis studied by scanning electron microscope. Many specimens show some retraction of the head and posterior mantle. Mantle shape is frequently cylindrical anteriorly and slightly expanded posteriorly. Arm 2 is generally longer than arm 1 after 2 mm dorsal mantle length (DML). Arm 3 develops around 2.0 mm DML but is too variable to include in an arm formula. Arm 4 develops around 2.4 mm DML. The proboscis tip bears 8 approximately equal sized suckers, evenly spaced and similarly orientated. The mean tentacle index prior to separation at the base is 3.74 .+-. 1.42 (1 std dev) n = 32. The proboscis is usually longer than all arms in length until 4.0 mm DML. Splitting of the proboscis base commences around 5.0 mm DML and earliest complete separation was observed at 8.4 mm DML. It is believed these larvae belong to Nototodarus sloani and Nototodarus gouldi. |
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