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Download (3398Kb) - ePrints Soton - University of Southampton

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independent <strong>of</strong> habitat or mode <strong>of</strong> nutrition during development. 2) Developmental<br />

patterns can be distinguished by habitat, using the pelagic or benthic feature. 3) The<br />

distinction between feeding and non-feeding development provides information about<br />

nutrition. All three characters should be used in order to unequivocally describe or<br />

classify a developmental pattern.<br />

Eight different developmental patterns can potentially be described using this<br />

classification when three characters exist, each with two alternative stages. Of these<br />

eight potential patterns only six are known to occur in asteroids:<br />

Indirect development by means <strong>of</strong> pelagic feeding larvae is common in<br />

asteroids and it can involve both bipinnarian and brachiolarian stages (e.g. Asterias<br />

rubens Linnaeus, Gemmill, 1914) or only bipinnarian stages (e.g. Astropecten<br />

scoparius , Oguro et al., 1976).<br />

Indirect development via pelagic non-feeding larvae can involve a simplified<br />

brachiolaria or the barrel-shaped larva.<br />

Indirect development on the benthos by means <strong>of</strong> a feeding larva possibly<br />

occurs in the Antarctic asteroid Odontaster validus Fisher, but this is still uncertain<br />

(Pearse & Bosch, 1986)<br />

Indirect development via a benthic non-feeding larva is common among<br />

brooding asteroid species (e.g. Ctenodiscus australis Lütken, Lieberkind, 1926;<br />

Henricia sanguinolenta (O.F. Müler), Masterman, 1902; Leptasterias hexactis Fisher,<br />

Chia, 1968).<br />

Pelagic non-feeding direct development has been observed only in Pteraster<br />

tesselatus (McEdward, 1992). Benthic non-feeding direct development has not been<br />

reported in the scientific literature yet, but McEdward & Janies assume it for the<br />

42

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