Intertidal bryozoans from coral reef-flat rubble Sa‘aga, Western Samoa

A study of the major cryptofaunal species from reef-flat rubble (slabs and small boulders) at Sa'aga, Upolu Island, has yielded 10 species of Bryozoa (2 new), with the following colonial morphologies: two-dimensionally encrusting - Puellina sp.; Calyptotheca mortoni n. sp., fixed-erect - Reteporellina samoensis n. sp., Triphyllozoon sp.; and rooted-articulated - Crisia elongata, Nellia
tenuis, Chlidonia pyriformis; Savignyella lafontii; Vasignyella otophora; Margaretta gracilior. Systematic rearrangements include placing Nellia in the Quadricellariidae, and the Savignyellidae in the superfamily Cateoicelloide Savignyella otophora is made the type species of a new genus Vasignyella. Bryozoa dominate numerically over other suspension feeders in this habitat. Much of the central portions of the rubble undersides are occupied by bryozoans, surrounded by sponges and ascidians, with the periphery dominated by crustose-coralline algae. Rooted, flexible Bryozoa can be so numerous as to form a turf.
The present collection is very small (a deliberate collection of bryozoans not having been made for the whole shore) but otherwise representative of the genera and morphotypes found elsewhere in such reefal environments.

对乌波卢岛（Upolu Island）萨阿加（Sa'aga）礁坪碎石（板状与小块岩石）中的主要隐生动物物种展开研究，共发现10种苔藓动物（Bryozoa）（含2个新种），其群体形态如下：二维包覆型——Puellina sp.、Calyptotheca mortoni新种；固着直立型——Reteporellina samoensis新种、Triphyllozoon sp.；根生分节型——Crisia elongata、Nellia tenuis、Chlidonia pyriformis、Savignyella lafontii、Vasignyella otophora、Margaretta gracilior。系统分类调整包括：将Nellia属归入Quadricellariidae科，将Savignyellidae科归入Cateoicelloide总科；Vasignyella otophora被指定为新属Vasignyella的模式种。在该栖息地中，苔藓动物在数量上占优于其他滤食性动物。碎石底面的大部分中央区域被苔藓动物占据，周围环绕着海绵与海鞘，边缘则以壳状珊瑚藻为主。根生且柔韧的苔藓动物数量可多至形成草皮状群落。本研究的样本量极小（未对整个海岸刻意采集苔藓动物），但在属级分类与形态类型方面，仍能代表此类礁体环境中其他区域的典型发现。