Field collection of Laevipilina hyalina McLean, 1979 from southern California, the most accessible living monoplacophoran

作者：Nerida G. Wilson, Danwei Huang, Miriam Goldstein, Ha-Rim Cha, Gonzalo Giribet, Greg W. Rouse · 发表于：Journal of Molluscan Studies · 年份：2009 · DOI：10.1093/mollus/eyp013 · 被引用次数：16 · 研究领域：Marine Biology and Ecology Research、Cephalopods and Marine Biology

Monoplacophora remain one of the most understudied and enigmatic molluscan groups to date. Thought to exist only as a fossil group, living specimens were recovered in 1952 from abyssal Pacific waters off Costa Rica (Lemche, 1957). This sensational discovery (Yonge, 1957) energized the debate about molluscan evolution. A suite of new monoplacophoran species was subsequently described, mostly from abyssal and hadal depths worldwide (Schwabe, 2008), including the Antarctic (e.g. Schrödl, 2006; Warén & Hain, 1992), and hydrothermal vents (Warén & Bouchet, 2001), bringing the known extant diversity to 31 species (see Haszprunar, 2008). These habitats are relatively difficult to access, and provide challenges to retrieving living specimens in significant numbers and good condition. Not surprisingly, many monoplacophoran studies suffer from little and/or poorly preserved material, and a lack of knowledge about the living animals. The shallowest known extant monoplacophoran Laevipilina hyalinaMcLean, 1979 is known from depths 174–388 m, along the Santa Rosa-Cortes Ridge in the continental borderland of southern California (McLean, 1979). It was the first monoplacophoran species to be photographed alive, and specimens were maintained in aquaria for a maximum of 25 days (Lowenstam, 1978). It is only known from a restricted range (Fig. 1), but has been collected from the type locality twice, most recently in 1977 (Lowenstam, 1978). We revisited this site to collect living specimens of L...