On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA

Abstract

Sixty species of hydroids, assigned to 24 families and 39 genera, are recognized and discussed in a collection of material from the southwest coast of Florida. One new species (Clytia joycei) is described from turtlegrass (Thalassia testudinum) and reported as well from the Caribbean coast of Panama. Under provisions of the First Reviser Principle in the International Code of Zoological Nomenclature, Antennopsis nigra Nutting, 1900 is assigned precedence over its simultaneous synonym A. longicorna Nutting, 1900. Also included as a synonym of A. nigra is A. sinuosa Fraser, 1947b. The species is now assigned to Nemertesia Lamouroux, 1816, as N. nigra. Following Reversal of Precedence provisions in the code, the well-known name Halecium nanum Alder, 1859 is designated as valid and conserved as a nomen protectum, while Hydra articulata Bosc, 1797 is relegated to a nomen oblitum. The genus Monotheca Nutting, 1900 is upheld as valid on the basis of both morphological and molecular evidence. Sertularia pourtalesi Nutting, 1904, a seldom-reported species, is assigned to Dynamena Lamouroux, 1812 and recognized as distinct from D. disticha (Bosc, 1802). Calyptospadix cerulea Clarke, 1882 and Bimeria franciscana Torrey, 1902 (also known as Garveia franciscana) are taken to be conspecific, with Calyptospadix Clarke, 1882 treated as a valid genus. Confusion over the identity of Lovenella gracilis Clarke, 1882 in literature on North American hydroids is addressed, and topotypic specimens from the Chesapeake Bay region are illustrated to document characters that distinguish the species. Campanularia colombiana (Wedler, 1976) is reported for the first time outside the Caribbean coast of Colombia. The fauna studied here consists largely of species known to occur in the tropical and subtropical western Atlantic. [Zoobank URL: urn:lsid:zoobank.org:act:4C926BE2-D75D-449A-9EAD-14CADACFFADD]

Some leptothecate hydroids (Cnidaria, Hydrozoa) from Hawaii, mostly from inshore and nearshore waters

“…These same studies also confirm that both C. elsaeoswaldae and C. gracilis (and its cryptic species) are distinct from C. hemisphaerica (Linnaeus, 1767). Hydroids of the latter species differ morphologically from those related congeners in having hydrothecal cusps that are rounded and erect rather than pointed and inclined to the right (when viewed laterally), and gonothecae that are spirally ribbed rather than smooth (Cornelius 1995b;Lindner et al 2011;Calder 2019). Stechow (1914) named two putatively distinct species, Clytia elsae-oswaldae and Thaumantias (?)…”

“…The distinction between Clytia elsaeoswaldae Stechow, 1914 andC. gracilis (M. Sars, 1850), often considered conspecific in the past, is now becoming more clear (Lindner et al 2011;Calder 2013Calder , 2019Cunha et al 2020). Characters said by Lindner et al to distinguish C. elsaeoswaldae from C. gracilis include a colony form that is stolonal or mostly so rather than branched, and gonothecae that arise from the hydrorhiza rather than from the pedicels.…”

“…Type material of that species included both trophosome and gonosome. The identity of the second species, based on an apparent juvenile, is a species inquirenda (Calder 2019).…”

“…Remarks. Clytia paulensis (Vanhöffen, 1910) has been reported from warm-temperate and tropical locations in the western and eastern Pacific, the western and eastern Atlantic, and the Indian Ocean (Calder 2019). It is also known from oceanic islands and seamounts such as Île Saint-Paul (Vanhöffen 1910), the Seychelles (Millard & Bouillon 1973), Madeira, the Canary Islands, the Islas Selvagens, and the Cape Verde Islands (Medel & Vervoort 2000), and Challenger Bank near Bermuda (Calder 2000).…”

“…Over the last few decades, Obelia oxydentata Stechow, 1914 (type locality: St. Thomas, U.S. Virgin Islands) has commonly been taken to be conspecific with O. bidentata Clark, 1875 (type locality: Long Island, New York, USA). A case has been made recently that they are indeed distinct, with O. oxydentata being recognized again as a valid species (Calder 2013(Calder , 2019Calder et al 2019). Obelia bidentata, taken to be a temperate to cool-temperate species with large (to 15 cm or more), extensively branched, and polysiphonic colonies, differs from the tropical to warm-temperate O. oxydentata, having small (usually 1 cm or less), unbranched, and monosiphonic colonies.…”