Diodogorgia nodulifera (Hargitt & Rogers, 1901)

Devictor, Susan T. & Morton, Steve L., 2010, Identification guide to the shallow water (0 - 200 m) octocorals of the South Atlantic Bight 2599, Zootaxa 2599 (1), pp. 1-62 : 32

Diodogorgia nodulifera (Hargitt, in Hargitt and Rogers, 1901)

( Figure 31 )

Solanderia nodulifera Hargitt , in Hargitt and Rogers 1901:279; Fig. C, 1 , 3–5 .

Solanderia crustata Hargitt , in Hargitt and Rogers 1901:280; Fig. C, 2 , 6–7 .

Diodogorgia ceratosa Kükenthal, 1919:97 ; Figs. 44 –52.— Deichmann 1936:86.

Diodogorgia cervicornis Kükenthal, 1919:645 .

Corallium vanderbilti Boone, 1933:51 ; Plates 12–14.

Diodogorgia nodulifera .— Deichmann 1936: 87; Plate 5 figs. 11–19.— Bayer 1959b:6; Fig. 3 .— Bayer 1961:73; Fig. 15 .— Cairns et al, 2002:33.

Material examined. USNM 60883, 61 m, off Jacksonville , Florida, March 11, 1980 . SERTC S 2698, 49 m, off Sapelo Island , GA, July 12, 1994 . USNM 49705, 73 m, off Palm Beach , Florida, April 26, 1950 .

Remarks. Fragments of the only two samples of this species recorded in the SAB were examined for this work, as well as a sample from a colony (USNM 49705) collected south of the SAB for comparison because of the variance in colony morphology. The southern colony displays the most common form and could conceivably be found in the SAB. The southern colony sample is yellow with red, moderately protruding polyp mounds and the cylindrical stem is approximately 5 mm in diameter. A ring of boundary canals divides the cortex and medulla. The cortex has a dense outer layer and spongy inner layer separated by a plexus of solenia. The outer cortex and polyp mounds contain small tuberculated spheroids, tuberculated, irregularly branched bodies, capstans and slender, warty, amber spindles. Also present are elongated, sparsely warted spindles. The neck of the polyps contain small, red tuberculated spheroids and branched bodies. The medulla contains light pink warted rods that are occasionally branched.

One sample from the SAB is an unbranched fragment that is entirely red with an inflated tip; this specimen appears to conform to some degree with Deichmann’s (1936) description of Diodogorgia ceratosa . The polyp mounds protrude much more than those of the southern specimen and are almost cylindrical. The coenenchyme completely surrounds a hollow tube similar to the description in Deichmann (1936), suggesting an encrusting nature around a worm tube. The cortical spindles are more robust than those in the southern specimen, and a few long, bent, coarsely warted spindles are present. The medulla contains branched, warted rods similar to those in the southern specimen, as well as spindles. It is noted that the small portion of material available for study limited sclerite examination.

Atlantic distribution: Georgia to Surinam, Gulf of Mexico, Caribbean, 20–183 m ( Deichmann 1936; Bayer 1959; Bayer 1961; NMNH collections; SERTC collection).

Figures

FIGURE 1. The South Atlantic Bight, which includes coastal waters between Cape Hatteras and Cape Canaveral, USA. The 200 m isobath is shown.

FIGURE 2. Branching colony forms; a) dichotomous (Iciligorgia schrammi); b) monopodial (Telesto sp.); c) whip-like branches (Leptogorgia virgulata); d) rod-like branches (Titanideum frauenfeldii); e) open, irregularly pinnate (Muricea pendula) f) planar (Leptogorgia hebes); g) lobed, with clusters of polyps (Pseudodrifa nigra).

FIGURE 3. Unbranched colony forms; a) flagelliform (whip-like) (Leptogorgia setacea); b) capitate (Nidalia occidentalis); c) foliose (Renilla reniformis) d) club-like (Sclerobelemnon theseus); e) pen-like (Virgularia presbytes); f) stoloniferous (Scleranthelia rugosa var. rugosa).

FIGURE 4. Anthocodiae of Thesea nivea. Indicated are pinnules (Pi), sclerites forming points (Po) and collaret (Col), tentacles (Te), neck (Ne), anthocodia (An) and calyx (Cal).

FIGURE 5. Pennatulaceans A, Renilla reniformis and B, Sclerobelemnon theseus, indicating the rachis (Ra), autozooids (Au), and peduncle (Pe) (scale bar = 1 cm).

FIGURE 6. Pennatulaceans A, Virgularia presbytes and B, Stylatula elegans, indicating autozooids (Au), polyp leaves (Pol. le.) and needles (Ne) (scale bar for A = 5 mm; B = 1mm).

FIGURE 7. A, Transverse and B, longitudinal cross-sections of scleraxonian octocoral axis (Diodogorgia nodulifera), showing inner cortex (In. cor.), outer cortex (Ou. cor.), spiculated medulla (Me), polyps (Pol), and ring of boundary canals (Bo. ca.).

FIGURE 15. a) Pseudodrifa nigra; b) Nidalia occidentalis (from Bayer, 1961); c) Bellonella rubistella.

FIGURE 31. Diodogorgia nodulifera: A, sclerites (S2698); a, b) rods from medulla; c–e) spindles from cortex; f) capstan from cortex (scale bar for a–c = 0.05 mm; d–f = 0.01 mm); B, preserved specimen S2698 (scale bar = 10 mm); C, branch of preserved specimen USNM 49705 (scale bar for B applies).

FIGURE 44. Leptogorgia setacea: A, sclerites (S2123); a, b) spindles from coenenchyme; c, d) disk spindles from coenenchyme; e) anthocodial rod (scale bar = 0.02 mm); B, colony attached to a bivalve shell; C, section of stem; (scale bar = 3 mm).