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The Solenogastres (less often referred to as Neomeniomorpha), common name the solenogasters, are one subclass of small, worm-like, shell-less molluscs (Aplacophora), the other subclass being the Caudofoveata (Chaetodermomorpha). Some recent literature, and recent molecular evidence, indicates that the Aplacophora may be polyphyletic, and therefore these taxonomists divide Solenogastres and Caudofoveata into separate classes.〔e.g. 〕 ==Morphology== In contrast to all other molluscan classes, the Aplacophora have no shell, and are instead covered by aragonitic sclerites (calcareous spicules), which can be solid or hollow. These spicules can be arranged perpendicular to one another within the cuticle to form a skeleton, or can stick up to form a palisade, or can lie flat against the cuticle. 80% of solenogaster species have a radula, while in others it is secondarily lost. The radula may bear one or more teeth per row; where there is more than one tooth, there is no central radular tooth.〔 The radula grows by dividing existing teeth in two, or by adding a new tooth at the centre of the radular row.〔 The salivary glands are very elaborate, and are an important character for taxonomy. Next to the mouth they have a unique sense organ, the vestibulum. The solenogastres do not have true ctenidia, although their gill-like structures resemble them. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「solenogastres」の詳細全文を読む スポンサード リンク
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