Eudendrium carneum Clarke, 1882

Calder, Dale R., 2019, On a collection of hydroids (Cnidaria, Hydrozoa) from the southwest coast of Florida, USA, Zootaxa 4689 (1), pp. 1-141 : 24-25

Eudendrium carneum Clarke, 1882

Figs. 2h, i , 5

Eudendrium carneum Clarke, 1882: 137 , pl. 7, figs. 10–17.— Wallace, 1909: 137.— Menzel, 1956: 2.— Joyce, 1961: 33, pl. 4, figs. 1–4.— Shier, 1965: 18, pl. 7.— Philp et al., 2003: 222.

Type locality. USA: Virginia, Hampton Roads, Fort Wool ( Clarke 1882: 137) .

Material examined. Sanibel Island, beach at Lighthouse Point, detached and stranded on shore, 13 December 2017, one colony, 15 cm high, without gonophores, coll. D. Calder, ROMIZ B4343. —Sanibel Island, beach at Lighthouse Point, detached and stranded on shore, 29 January 2018, one colony fragment, 5 cm high, with female gonophores, coll. D. Calder, ROMIZ B4344.

Remarks. Eudendrium carneum was first described by Clarke (1882) from Hampton Roads, Virginia, USA, an important naval and commercial port within Chesapeake Bay. A common component of the fouling community (e.g. McDougall 1943; Sutherland 1974, 1978, 1981; Sutherland & Karlson 1977; Karlson & Osman 2012; Oliveira et al. 2016) and a hydroid having a wide geographic distribution, the species has likely been dispersed, at least in part, by shipping ( Watson 1985). In the western North Atlantic, it has been reported from southern Massachusetts to the southern Caribbean Sea (see records below). Previous reports of E. carneum to the north of Cape Cod on this coast, such as that by Fraser (1944) from Nova Scotia (Misaine Bank E of Cape Canso, 45°22’N, 58°43’45”W, 137 m), are believed here to have been based on misidentifications given temperature tolerances of the species (Calder 1990). Eudendrium carneum is essentially a warm-temperate to tropical species, unlikely to occur in boreal waters.

A combination of morphological characters distinguish E. carneum from its numerous congeners. Hydroids of the species are typically robust and extensively branched, with polysiphonic hydrocauli and polysiphonic or monosiphonic branches. The nematocyst complement comprises small microbasic euryteles (7.9–9.0 μm long x 3.3–3.9 μm wide, un- discharged, n=10, ROMIZ B4343) and large heterotrichous anisorhizas (26.3–29.5 μm long x 10.5–12.7 μm wide, un- discharged, n=10, ROMIZ B4343), the latter arranged in a band around the base of each hydranth as well as occurring on the hypostome and male gonophores. Both male and female gonophores are borne on reduced or aborted hydranths. Those of the male occur on several peduncles, each of which comprises a linear series of up to five chambers; the distalmost chamber is armed with heterotrichous anisorhizas. Most importantly, female gonophores are distinguished in having a bifid spadix that curves over the egg; with development, embryos surrounded by capsules of perisarc appear in clusters along ultimate branchlets. Hydranths and gonophores are reddish to orange in colour.

A species much like E. carneum is E. tayronensis , recently described by Wedler (2017a) from a coastal lagoon (Bahía de Chengue) in Colombia. That species differs from E. carneum in having branched gonophore peduncles in the male and embryos that are completely rather than partially enclosed in the female.

Additional details on the hydroid of E. carneum are given elsewhere ( Calder 1988, 2010, 2013; Schuchert 2008).

Reported distribution. Gulf coast of Florida. Dry Tortugas ( Wallace 1909: 137).—St. George Sound— Apalachee Bay region ( Menzel 1956: 2).—Seahorse Key ( Joyce 1961: 33).—Cape San Blas area ( Shier 1965).— Dickerson Bay ( Philp et al. 2003: 222).

Elsewhere in western North Atlantic. USA: South Carolina, Sullivan’s Island ( McCrady 1859: 167, as Eudendrium ramosum ).— USA: South Carolina, Charleston (A. Agassiz 1865: 160, as Eudendrium ramosum ).— USA: Virginia, Hampton Roads, Fort Wool ( Clarke 1882: 137).— USA: no location given, but in collections of the U.S. Fish Commission at Woods Hole, Massachusetts ( Nutting 1901: 333).— Bermuda: location unspecified ( Congdon 1906: 27, 1907: 464, as Eudendrium ramosum ).— USA: Massachusetts, Martha’s Vineyard, Vineyard Haven + off Naushon Island + Gay Head ( Hargitt 1908: 97).— USA: Massachusetts, Woods Hole ( Fraser 1912a: 42; Weill 1934: 388, as Eudendrium ramosum ).— USA: North Carolina, Beaufort area ( Wilson 1911: 282).— USA: North Carolina, Morehead City + Beaufort + Shackleford Banks, 12 ft (4 m) ( Fraser 1912b: 349).— Bermuda: Hamilton Harbour ( Bennitt 1922: 245, as Eudendrium ramosum ).— USA: North Carolina, Beaufort ( Wilson 1923: 40; Pearse 1936: 178; McDougall 1943: 337).— USA: Massachusetts, off Chatham, 41°38’N, 69°53’W, 7.5 ftm (14 m) + 5.75 miles (12 km) off Chatham Light, 14 ftm (26 m) + SE of Nantucket, 46 ftm (84 m) + between Nantucket and High Duck Islands, 4 ftm (7 m) + Nantucket Sound, 18 ftm (33 m) + off Martha’s Vineyard, 396 ftm (724 m) + Vineyard Sound, near West Chop Light, 14 ftm (26 m) + off West Falmouth, 7 ftm (13 m) + off Naushon Island + Buzzards Bay ( Fraser 1944: 65).— USA: Rhode Island, Tiverton + Narragansett Bay, off Fort Dumpling, 20 ftm (37 m) ( Fraser 1944: 65).— USA: New York, Long Island, Greenport ( Fraser 1944: 65).— Puerto Rico: N of Culebra Island, 18°19’10”N, 65°19’40”W, 10 ftm (18 m) ( Fraser 1944: 65).— USA: North and South Carolina, reefs on the continental shelf (Pearse & Willams 1951: 136).— USA: North Carolina, Beaufort area ( Maturo 1959: 123; Wells 1961: 246; Sutherland 1974: 861; 1978: 258; 1981: 503; Sutherland & Karlson 1977: 427; Karlson 1978: 231; Lindquist & Hay 1996: 448; Schmitt et al. 1998: 126; Stachowicz & Hay 1999: 2086). — USA: North Carolina, Core Banks, on Aequipecten gibbus , 17–20 ftm (31–37 m) ( Wells et al. 1964: 566).— USA: Massachusetts: Woods Hole region ( Petersen 1964: 18; Wyttenbach et al. 1973: 364).— Venezuela: Puerto Cabello ( Vervoort 1968: 8).— Costa Rica, Limón ( Vervoort 1968: 8).— Bermuda: Flatts Bridge ( Summers 1972: 149, as Eudendrium ramosum ).— Colombia ( Wedler 1975: 340; Flórez González 1983: 123; Criales 1984: 309; Bandel & Wedler 1987: 35).— USA: South Carolina, estuaries across the state ( Calder & Hester 1978: 89).— USA: North Carolina, Bogue Sound ( Bynum 1980: 227).— USA: Florida, Indian River region ( Winston 1982: 164; 2009: 232).— USA: South Carolina and Georgia, inner, middle and outer continental shelf ( Wenner et al. 1984: 20, 39).— USA: South Carolina, North Inlet, pilings + Murrells Inlet, jetties + Charleston area + Folly River + Breach Inlet, jetties + Isle of Palms, marina, floating docks + Beaufort area, marinas, floating docks ( Fox & Ruppert 1985: 84, 92, 140, 162, 167, 177, 232).— USA: Louisiana, shelf hard bottoms ( Putt et al. 1986: 56).— Bermuda: shallow inshore waters ( Calder 1986).— Puerto Rico: La Parguera, 1–2 m ( Wedler & Larson 1986: 84).— USA: Louisiana, on coastal petroleum platforms, 12–18 m ( Lewbel et al. 1987: 214).— Bermuda: Hamilton Harbour, 2.5 m + Flatts Inlet, 0.5–2 m + Castle Harbour, Castle Grotto, 1 m + Ferry Reach, 0.5–2 m + Somerset Bridge, 2 m ( Calder 1988: 43).— USA: South Carolina and Georgia, inner continental shelf, on artificial reefs ( Wendt et al. 1989: 1119).— USA: North Carolina, Beaufort ( Walters 1992: 1102).— USA: North Carolina (Lindquist 1996: 435).— USA: North Carolina, Beaufort ( Holm et al. 1997: 192).— USA: North Carolina, Wrightsville Beach ( Henrikson & Pawlik 1998: 252).— Bermuda: “ Hamilton Sound” (=Great Sound?) + Gibbons Bay ( Marques et al. 2000: 90).— USA: Florida, Miami, Ragged Keys, 25°47’N, 80°11’W + Guard Bridge, 25°47’N 80°11’W ( Marques et al. 2000: 91).— USA: Georgia: St. Catherines Island, main dock ( Prezant et al. 2002: 22).— Costa Rica: Limón ( Kelmo & Vargas 2002: 602).— USA: Florida, Biscayne Bay ( Jones 2002: 216.— Panama: Colón, Fort Sherman dock, 0–2 m + Colón, bridge near Fort Sherman, 0–1 m + Bocas del Toro, Swan’s Key, 1–4 m + Bocas del Toro, Bastimentos, 1–4 m + Bocas del Toro, Drago, 2–4 m ( Calder & Kirkendale 2005: 479).— Honduras: Utila, 16.0687°N, 86.9555°W, 20 m ( Schuchert 2008: 700).— USA: Massachusetts, (Martha’s Vineyard), Lagoon Pond Bridge ( Schuchert 2008: 700).— USA: Florida, Fort Pierce Inlet, north jetty, intertidal ( Calder 2013: 13).—Caribbean Sea ( Wedler 2017b: 31, figs. 14A, B, 15–17, 18A, B).— Mexico: Alacranes Reef, on algae, buoys, chains, shipwreck ( Mendoza-Becerril et al. 2018b: 129).— Cuba: Havana, coral reef system west of the city (Castellanos et al. 2018: Supplementary Table S2).— Panama: Bocas del Toro area, Punta Hospital + Swan’s Cay ( Miglietta et al. 2018b: 108).

Figures

FIGURE 2. a, Bimeria humilis: colony with two hydranths, Fort Myers Beach, ROMIZ B4330. Scale equals 0.2 mm. b, Bougainvillia rugosa: part of colony with hydranth and medusa bud, Sanibel Island, ROMIZ B4333. Scale equals 0.2 mm. c, Bougainvillia rugosa: newly liberated medusa from same hydroid, ROMIZ B4333. Scale equals 0.1 mm. d, Bougainvillia rugosa: 3-day-old laboratory-raised medusa from same hydroid, ROMIZ B4333. Scale equals 0.1 mm. e, Calyptospadix cerulea: part of hydrocaulus with branches, pedicels, hydranths, and a female gonophore, Caloosahatchee River at Fort Myers, ROMIZ B4340. Scale equals 0.3 mm. f, Amphinema sp.: hydranth and pedicel, Captiva Island, ROMIZ B4338. Scale equals 0.2 mm. g, Amphinema sp.: hydranth and pedicel, Captiva Island, ROMIZ B4338. h, Eudendrium carneum: hydranth and pedicel, Sanibel Island, ROMIZ B4343. Scale equals 0.2 mm. i, Eudendrium carneum: part of female colony with encapsulated embryos, Sanibel Island, ROMIZ B4344. Scale equals 0.4 mm.

FIGURE 5. Eudendrium carneum: nematocysts of hydranth, ROMIZ B4343. a, microbasic heterotrichous eurytele. b, heterotrichous anisorhiza.