In lieu of an abstract, here is a brief excerpt of the content:

The Phoronida comprises 2 genera and at least 10 recognized species (Emig 1982), the majority of which exhibit a distinctive larval form known as the actinotroch (Zimmer 1991). Phoronids often occur in conspecific aggregations , and most species exhibit cosmopolitan distributions (Emig 1982, Zimmer 1991). Traditionally phoronids, brachiopods , and bryozoans have been designated as separate phyla within the Lophophorata and are believed to share morphological characteristics with basal deuterostome phyla (Brusca and Brusca 2003). However, molecular phylogenetic evidence has consistently identified the phoronids and brachiopods as a monophyletic group within the lophotrochozoan protostomes (Halanych et al. 1995, Cohen 2000, Helfenbein and Boore 2004), and although the bryozoans are also considered lophotrochozoans, their position relative to the phoronids and brachiopods has not been resolved (Halanych 2004, Passamaneck and Halanych 2004). One proposed resolution of the molecular phylogenetic evidence and Linnaean classification of phoronids and brachiopods was to include the phoronids as a subphylum within the phylum Brachiopoda (Cohen 2000). This interpretation has yet to be widely accepted into recent revisions of brachiopod systematics, and for the purposes of this chapter the phoronids will be treated as a phylum separate from the Brachiopoda. Phoronid systematics has been based largely on the arrangement of longitudinal muscles in the body wall, lophophore morphology, and the nephridial morphology of adults (Emig 1974, 1979, and 1982). However, reproductive traits and characteristics of competent larvae are also informative taxonomic characters (Santagata and Zimmer 2002). More importantly, a review of larval and adult characters within the Phoronida clearly shows that its species diversity is currently underestimated (Santagata and Zimmer 2002). Two controversial species that occur within the Gulf of Mexico are Phoronis architecta (Andrews, 1890) and P. psammophila (Cori, 1889). Emig (1977) proposed that P. architecta (type locality: Beaufort, North Carolina, U.S.A.) should be considered a junior synonym under P. psammophila (type locality: Messina, Italy) based on the similarity between the longitudinal muscle arrangement and nephridia morphology of adult specimens. However, P. psammophila has been described as a dioecious brooder with specialized nidamental glands and Phoronis architecta as a dioecious free-spawner that lacks nidamental glands (Brooks and Cowles 1905, Stan1133 65 Phoronida of the Gulf of Mexico Scott Santagata  Phoronida. After Hyman 1955, modified by F. Moretzsohn. 1134 ~ Phoronida Gulf of Mexico but has not been recorded is Phoronis ovalis (Wright, 1856). This species is smaller than other phoronid species, produces a slug-like larva, and has been found in burrows in the shells of the common jingle shell, Anomia simplex (d’Orbigny, 1842), from the Atlantic coast of the southeastern United States (Stancyk, Maturo Jr., and Heard Jr. 1976) and also Stramonita (=Thais) haemostoma floridana (Conrad, 1837) from Brazil (Marcus 1949, Forneris 1959). Abbreviations Abbreviations used in the checklist are: csp = cosmopolitan ; hsb = hard substrate; itd = lower intertidal; ne = northeast; nw = northwest; plk = planktonic; sft = soft substrate; sw = southwest. Acknowledgments This work was completed during a postdoctoral fellowship at the Smithsonian Marine Station (Fort Pierce, Florida ). I thank the staff of the Smithsonian Marine Station, Friday Harbor Laboratories, Mary Rice, Valerie Paul, Darryl Felder (University of Louisiana at Lafayette), John Wes Tunnell (TAMU), Richard Greene (Smithsonian Libraries ), Kris Metzger (HBOI library), Ed Ruppert (Clemson University), Dennis Allen (BMFL), Dan Rittschof (Duke Marine Laboratory), Richard Strathmann (FHL), and Russel L. Zimmer (USC). This publication is contribution 714 for the Smithsonian Marine Station at Fort Pierce. References 1. Andrews, E. A. 1890. On a new American species of the remarkable animal Phoronis. Annales and Magazine of Natural History 5: 445–449. 2. Brooks, W. K., and R. P. Cowles. 1905. Phoronis architecta: its life history, anatomy and breeding habits. Memoirs of the National Academy of Sciences 10: 71–148. 3. Brusca, R. C., and G. J. Brusca, 2003. Invertebrates. 2nd ed. Sinauer, Sunderland, Massachusetts. 936 pp. 4. Cohen, B. L. 2000. Monophyly of brachiopods and phoronids: reconciliation of molecular evidence with Linnaean classification (the subphylum Phoroniformea nov.). Proceedings of the Royal Society of London. Series B 267: 225–231. 5. Cori, C. J. 1889. Beitrag zur Anatomie der Phoronis [inaugural-dissertation]. University of Leipzig. Prague, Germany. 48 pp. cyk, Maturo Jr., and Heard Jr. 1976, Emig 1979). Also the competent larvae of these species have different anatomical traits (Brooks and Cowles 1905, Herrmann 1979, Santagata and Zimmer 2002). Emig has asserted that the reproductive traits described for P. architecta in Brooks and Cowles (1905) actually belong to a co-occurring species , P. muelleri (Selys-Longchamps, 1903) Unfortunately, there have been no investigations of the reproductive characteristics...

Share