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''Rehderella belyaevi'' is an unusual and monotypic barnacle genus restricted to Easter Island and Pitcairn Island. Two other barnacle species are found in the intertidal zone of these islands. ''Euraphia devaneyi'' is much larger, and possesses calcareous basis. ''Tesseropora'' sp. has four shell plates with a single row of pores in shell wall. Both ''Euraphia'' and ''Rehderella'' have six shell wall plates. ''Rehderella'' differs from both in its membraneous basis and fusion of opercular plates on each side. ''Nesochthamalus intertextus'' is the only other Pacific Ocean barnacle with fused opercular plates. ''Nesochthamalus'' possesses a partially calcareous saucer-shaped basis, and fused opercular plates which show no visible trace of former articulation. ''Rehderella'' shows a line at the former articulation. == Diagnosis and discussion == Shell wall of six plates with membraneous basis, and no basal infolding of shell wall. Sutures between wall plates are straight, and do not fuse at any time during its life cycle. The animal is small, about 5 mm length, and flattened, with a pinkish-yellow color.〔 Opercular plates of ''Rehderella'' are distinctive in the scutum and tergum of each side fusing in young stages. A slight step in basal margin marks the former articulation between plates. Scutal adductor scar is deep and narrow, depressor pit indistinct. Tergal depressor crests 6-8, distinct, depending from basal margin.〔〔 Soft part distinctions include card setae on cirri develop only after animal reaches a size of 5 mm.〔 Caudal appendages are present, growing longer with age, up to 20 segments in large specimens.〔 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「Rehderella」の詳細全文を読む スポンサード リンク
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