Idiellana pristis ( Lamouroux, 1816 )

Calder, Dale R., 2019, On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA, Zootaxa 4689 (1), pp. 1-141 : 85-86

Idiellana pristis ( Lamouroux, 1816)

Figs. 21e, f

Idia pristis Lamouroux, 1816: 199 , pl. 5, figs. 5a, B—E.

Idia .— Nutting, 1895: 180.

Idiella pristis .— Leloup, 1935a: 37, figs. 19–21.

Idiellana pristis .— Van Gemerden-Hoogeveen, 1965: 16.

Type locality. Indonesia: “Côtes de la Nouvelle-Hollande” ( Lamouroux 1816: 199, as Idia pristis ) .

Material examined. Fort Myers Beach, stranded on shore, 16 February 2013, several colonies, up to 9.5 cm high, without gonophores, ROMIZ B4414.— Fort Myers Beach , stranded on shore, 16 February 2013, one colony, 11 cm high, without gonophores, ROMIZ B4415 .— Fort Myers Beach , stranded on shore, 01 March 2013, several colonies, up to 13 cm high, without gonophores, ROMIZ B4416 .— Sanibel Island , beach at Lighthouse Point, detached and stranded in tidepool, 30 March 2013, one colony, 4.8 cm high, without gonothecae, coll. D. Calder, ROMIZ B4389 .— Sanibel Island , beach at Lighthouse Point, 26°26’57”N, 82°01’07”W, detached, in intertidal pool, 03 August 2014, one juvenile colony, 1.6 cm high, without gonophores, coll. D. Calder, ROMIZ B4390 .— Sanibel Island , beach at Lighthouse Point, 26°26’58”N, 82°01’04.5”W, on detached shell debris at water’s edge, 21 March 2018, 22° C, 34.5‰, one colony, 7 mm high, without gonophores, coll. D. Calder, ROMIZ B4391 .

Remarks. Records of Idiellana pristis ( Lamouroux, 1816) in the western North Atlantic have mostly been from the Caribbean region. Even there, they have been quite limited in number, with reports from Martinique ( Fraser 1944, as Idiella pristis ), Puerto Rico ( Fraser 1944, as Idiella pristis ), St. Thomas ( Vervoort 1968), and Colombia ( Wedler 1975, as Idiella pristis ; Flórez González 1983; Bandel & Wedler 1987; Quiceno & Palacio 2008, as Idiella pristis ; Wedler 2017b). To the north, records exist from both the Dry Tortugas and Key West, Florida ( Nutting 1895, as Idia ; Leloup 1935a, as Idiella pristis ; Van Gemerden-Hoogeveen 1965), and from the northeast coast of Cuba ( Varela & Cabrales 2010). The species has yet to be reported along the east coast of the United States. Present records extend the known range northwards to Sanibel Island, Florida, in the southeastern Gulf of Mexico.

Elsewhere, hydroids of I. pristis have been reported several times from Brazil ( Oliveira et al. 2016), although a report in that work of the species from “La Tortuga Island ”, Venezuela, is believed here to be a misinterpretation of records from the Dry Tortugas, Florida. The species has a wide geographic range over tropical and subtropical areas of the Atlantic, Pacific, and Indian oceans ( Vervoort 1993; Vervoort & Watson 2003), but it has yet to be reported from the eastern Pacific. Its known bathymetric range is from 0 m to 183 m ( Fraser 1944; Calder & Cairns 2009; Fernandez & Marques 2018), with most records being from intermediate depths ( Vervoort 1993).

The hydroid is distinctive in having unbranched hydrocladia with a double row of alternate, adnate, distally projecting hydrothecae ( Schuchert 2003). The specific name of the species is derived from the resemblance of these hydrocladia to the rostrum of the sawfish, Pristis pristis ( Linnaeus, 1758) ( Lamouroux 1816: 199; Millard 1975: 270).

Earlier generic names applied to this species, Idia Lamouroux, 1816 and its replacement name Idiella Stechow, 1919 , are invalid in being junior homonyms of Idia Hübner, 1813 (Lepidoptera) and Idiella Brauer & Bergenstamm, 1890 (Diptera) respectively. Hübner had used the name Idia even earlier (1808), but it appeared in a pamphlet (Erste Zuträge zur Sammlung exotischer Schmetterlinge) that has been rejected for nomenclatural purposes (ICZN 1966, Opinion 789) in failing to meet Criteria of Publication in Zoological Nomenclature (ICZN Art. 8). That pamphlet is listed as Title Number 72 in the Official Index of Rejected and Invalid Works in Zoological Nomenclature. In the same ruling (Opinion 789), Idia Hübner, 1808 (Name No. 1863) and Idia Lamouroux, 1816 (Name No. 1864) were both placed on the Official Index of Rejected and Invalid Generic Names in Zoology. The replacement name Idiellana , proposed by Cotton & Godfrey (1942), is in current use supplanting the junior homonym Idiella Stechow, 1919 .

Molecular data confirm the inclusion of Idiellana in Sertulariidae Lamouroux, 1812 . Its assignment to a separate family (Idiidae Allman, 1888) or even to a distinct taxon of higher rank (legion Thalamophora Allman, 1888), as proposed by Allman (1888: lii, 82, 83), is unwarranted. The phylograms of Maronna et al. (2016) include Idiellana pristis in a clade with several species of the sertulariid genus Dynamena Lamouroux, 1812 , especially D. moluccana ( Pictet, 1893) .

Reported distribution. Gulf coast of Florida. Key West area, shallow water ( Nutting 1895: 180, as Idia ).— Dry Tortugas ( Leloup 1935a: 39, as Idiella pristis ; Van Gemerden-Hoogeveen 1965: 16).

Elsewhere in western North Atlantic. French Lesser Antilles: Martinique ( Fraser 1944: 312, as Idiella pristis ).— Puerto Rico: north coast, 18°31’N, 66°10’15”W, 38 ftm (69 m) + 18°30’30”N, 66°23’05”W, 40 ftm (73 m) + 18°30’24”N, 66°04’15”W, 100 ftm (183 m) + 18°30’N, 66°12’20”W, 46–56 ftm (84–102 m) + 18°23’35”N, 65°37’10”W, 10 ftm (18 m) ( Fraser 1944: 312, as Idiella pristis ).— Virgin Islands of the United States: St. Thomas, Sound + Savannah Passage ( Vervoort 1968: 36, 37).— Colombia: Santa Marta area, rocky littoral ( Wedler 1975: 340, as Idiella pristis ; Bandel & Wedler 1987: 41).— Colombia: Bahía de Cartagena, Ciénaga del Picón, mangroves, 0.2–2 m ( Flórez González 1983: 123).— Colombia: Ciénaga de La Boquilla, mangroves ( Quiceno & Palacio 2008: 71, as Idiella pristis ).— Cuba: Bahía de Puerto Padre, entrance channel, 5 m ( Varela & Cabrales 2010: 105).—Caribbean Sea ( Wedler 2017b: 128, figs. 128, 129).

Figures

FIGURE 21. a, Amphisbetia distans: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4387. Scale equals 0.1 mm. b, Amphisbetia distans: gonotheca, Sanibel Island, ROMIZ B4386. Scale equals 0.1 mm. c, Dynamena disticha: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4410. Scale equals 0.1 mm. d, Dynamena pourtalesi: part of hydrocaulus with two hydrothecal pairs, Southwest Florida Shelf, ROMIZ B306. Scale equals 0.2 mm. e, Idiellana pristis: base of hydrocaulus with a branch, Sanibel Island, ROMIZ B4390. Scale equals 0.2 mm. f, Idiellana pristis: part of branch with hydrothecae, Sanibel Island, ROMIZ B4390. Scale equals 0.1 mm. g, Tridentata turbinata: part of hydrocaulus with two hydrothecal pairs, Sanibel Island, ROMIZ B4393. Scale equals 0.2 mm. h, Sertularella areyi: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B1978. Scale equals 0.2 mm. i, Sertularella diaphana: part of colony with three hydrothecae, Southwest Florida Shelf, ROMIZ B4392. Scale equals 0.2 mm. j, Sertularella unituba: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B2001. Scale equals 0.2 mm.