<p class="HeadingRunIn"><strong><em>Capitella teleta</em>, a new species designation for the opportunistic and experimental <em>Capitella</em> sp. I, with a review of the literature for confirmed records</strong></p>

Abstract

This paper provides a morphological description of Capitella teleta sp. nov., an opportunistic capitellid that is also commonly used as an experimental polychaete under the provisional designation Capitella sp. I. The species is widely distributed along the east and west coasts of North America and also reported from Japan and the Mediterranean. The species belongs to a group having distinct sexual dimorphism, yet with hermaphrodites occurring under certain conditions. Morphologically, C. teleta has a long, narrow body, with all thoracic segments similar except for sexual modifications on setigers 8–9; the prostomium/peristomium combined are long, narrow and about 2.5 times as long as setiger 1. Capillary setae are present in noto- and neuropodia of setigers 1–7; setigers 8–9 have hooded hooks in noto- and neuropodia of females; genital spines replace notopodial hooks in males. A methyl green staining pattern is limited to some thoracic setigers of females; males lack a distinct staining pattern. The cytochrome oxidase I (COI) sequence is presented. Relationships of C. teleta with the type-species, C. capitata and other known species including siblings identified in laboratory culture are discussed. The syntype of Ancistria acuta Verrill, 1874, the only known species of Capitella described from New England was examined and determined to be incertae sedis. C. teleta is a highly opportunistic species and appears to be the same as the C. capitata identified from southern California as the “polluted zone indicator” by D.J. Reish in the late 1950s. An appendix with over 200 published references to research conducted on C. teleta is included.

Taxonomy and phylogeny of mud owls (Annelida: Sternaspidae), including a new synonymy and new records from the Southern Ocean, North East Atlantic Ocean and Pacific Ocean: challenges in morphological delimitation

“…Connectivity over large geographic ranges in marine taxa can be determined by a number of factors, including oceanographic currents, the physiology and behaviour of larvae, and connectivity cycles that span multiple generations, as found for the ornate spiny lobster Panulirus ornatus (Fabricius, 1798), which similarly displays genetic homogeneity across a distributional range of up to 10,000 km from Australia to Vietnam (Dao et al 2015). Anthropogenic factors may also play a role-dispersal by ships' ballast water is thought to account for the connectivity between northwest Atlantic and northwest Pacific populations of the capitellid polychaete Capitella teleta Blake, Grassle & Eckelbarger, 2009(Tomioka et al 2016.…”

Cryptic polychaete diversity: a review

“…; Dean ; Blake et al . ). The results from such bioassays may not be comparable if different species has been used among those studies, and the results from a single study may also be confounded if more than one species in a cryptic complex was used (Åkesson ).…”

Molecular Phylogeny of the Family Capitellidae (Annelida)

“…3). The implication of the monophyly of Capitella is that it should form the basis for research to illustrate evolutionary histories of habitat expansion [e.g., sand interstices (Green, 2002), whale bones (Silva et al, 2016), and squid mass egg (Hartman, 1947)], diversification of larval developmental forms [lecithotrophy, planktotrophy (Blake et al, 2009), and poecilogony (e.g., Chia et al, 1996;Tsutsumi, 2005)], and other interesting features found in this genus.…”

“…The family Capitellidae Grube, 1862 consists of freeliving, benthic, earthworm-like annelids and contains about 190 species (Rouse and Pleijel, 2001;Read, 2010). It includes Capitella teleta Blake, Grassle & Eckelbarger, 2009, formerly known as "Capitella sp. I" (Grassle and Grassle, 1976), which is now used as a model annelid in the field of evolutionary developmental biology, and for which the complete genome has been sequenced (e.g., Ferrier, 2012;Seaver et al, 2012;Lauri et al, 2014;Seaver, 2016).…”

“…Rouse and Pleijel (2001: p. 44) remarked, "the taxonomy of Capitellidae is in serious need of revision", because genera were, and still are, defined in a way that does not reflect phylogeny. Genera have been diagnosed based on unique combinations of morphological characters, such as the shape of the head, number of thoracic segments, arrangement/type of chaetae, presence or absence of branchiae, and shape of the pygidium (Fauchald, 1977;Blake et al, 2009). This 'unique combination' approach itself is unlikely to lead to monophyletic taxa (Sundberg, 1993;Sundberg and Pleijel, 1994), and one diagnostic character, the arrangement of chaetae, is known to change ontogenetically within individuals (Ewing, 1982;Fredette, 1982;George, 1984).…”