Lafoea coalescens Allman, 1877

Calder, Dale R., 2019, On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA, Zootaxa 4689 (1), pp. 1-141 : 29-30

Lafoea coalescens Allman, 1877

Fig. 6e

Lafoea coalescens Allman, 1877: 13 , pl. 10, figs. 1, 2.— Fraser, 1943: 90.

Type locality. USA: Florida, south of the Marquesas Keys , 140 ftm (256 m) ( Allman 1877: 13) .

Material examined. Southwest Florida Shelf, inner shelf west of North Naples, 26°16.82’N, 82°44.02’W, 32.3 m, 19 July 1981, triangle dredge, one colony fragment, 2.7 cm high, without gonophores, coll. Continental Shelf Associates, ROMIZ B1914.— Southwest Florida Shelf , outer shelf northwest of the Dry Tortugas, 25°16.83’N, 83°57.35’W, 127 m, 03 August 1981, triangle dredge, several colony fragments, up to 3 cm high, without gonophores, coll. Continental Shelf Associates, ROMIZ B1915 .

Remarks. Lafoea coalescens Allman, 1877 is morphologically distinctive amongst its congeners. Its hydrothecae are quite unusual in having flared margins and symmetrical or nearly symmetrical walls, and its pedicels exist in two forms. They may be either straight, long, free from hydrocaulus and branches, and annulated basally, or curved, relatively short, partly adnate to hydrocaulus and branches, and smooth throughout. An infrequently reported species, records nevertheless suggest that it is widely distributed. After being originally described from the Marquesas Keys, Florida, hydroids of the species have been reported from Bermuda (Calder 1990 [1991a]), Bowditch Seamount near Bermuda ( Calder 2000), the Blake Plateau ( Henry et al. 2008), and the Almirante Saldanha Seamount (22.38°S, 37.58°W) off Brazil ( Miranda et al. 2015). Lafoea coalescens also appears to have a wide bathymetric range, having been reported at depths from 32 m (this study) to 1285–1381 m ( Calder 2000). It may be a predominantly bathyal species that penetrates into neritic waters.

A more detailed account of the species is given elsewhere (Calder 1990 [1991a]). The gonosome has yet to be described.

Reported distribution. Gulf coast of Florida. South of the Marquesas ( Allman 1877: 13; Fraser 1943: 90; 1944: 221).

Elsewhere in western North Atlantic. Bermuda: 2 km SE of Castle Roads , 60–90 m, on calcareous rubble (Calder 1990 [1991a]: 37).—Bowditch Seamount, NNE of Bermuda, 32°44’N, 64°32.8’W, 1285–1381 m, on coral rubble ( Calder 2000: 1134) .— USA: Blake Plateau off Cape Canaveral , Florida, 28.7931, -79.6214, 737 m, 6.7° C, on dead corals ( Henry et al. 2008: 791) .

Figures

FIGURE 6. a, Acryptolaria longitheca: part of colony with two hydrothecae, Southwest Florida Shelf, ROMIZ B1902. Scale equals 0.2 mm. b, Acryptolaria longitheca: two gonothecae from a coppinia, Southwest Florida Shelf, ROMIZ B1902. Scale equals 0.1 mm. c, Acryptolaria tortugasensis: part of colony with three hydrothecae, Southwest Florida Shelf, ROMIZ B1906. Scale equals 0.2 mm. d, Acryptolaria tortugasensis: part of colony with a hydrotheca, Southwest Florida Shelf, ROMIZ B1906. Scale equals 0.1 mm. e, Lafoea coalescens: part of colony with four hydrothecae, Southwest Florida Shelf, ROMIZ B1915. Scale equals 0.2 mm. f, Synthecium tubithecum: part of colony with two hydrothecal pairs, Southwest Florida Shelf, ROMIZ B1929. Scale equals 0.2 mm. g, Zygophylax convallaria: part of colony with four hydrothecae, Southwest Florida Shelf, ROMIZ B1921. Scale equals 0.2 mm. h, Zygophylax convallaria: part of colony with a hydrotheca, Southwest Florida Shelf, ROMIZ B1921. Scale equals 0.1 mm. i, Zygophylax convallaria: nematophorous ramule, Southwest Florida Shelf, ROMIZ B1921. Scale equals 0.1 mm. j, Zygophylax convallaria: gonotheca, Southwest Florida Shelf, ROMIZ B1921. Scale equals 0.1 mm.