Description of the eudoxid stages of Lensia havock and Lensia leloupi (Cnidaria: Siphonophora: Calycophorae), with a review of all known Lensia eudoxid bracts

摘要

The majority of calycophoran siphonophores release cormidia from the end of the polygastric colony to form a free-living sexual unit, called the eudoxid stage. Despite having a very different morphology from that of the polygastric colony, nearly all calycophoran species have had their eudoxid stages described, through a combination of morphological and distributional similarities with the polygastric stages. However, in the catch-all genus Lensia, less than half of the small, rocket-shaped polygastric stages have had eudoxid stages assigned to them. In this work, DNA barcoding of the mitochondrial 16S gene allowed two new Lensia eudoxid stages to be reliably linked with their polygastric stages: L. havock and L. leloupi. A re-examination of the latter species has indicated that L. nagabhushanami is a junior synonym. A review of all known Lensia eudoxid bracts is given, with some notes on five as-yet unassigned eudoxid stages.