Titanideum frauenfeldii ( Kölliker, 1865 )

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 : 35-37

Titanideum frauenfeldii ( Kölliker, 1865)

( Figure 33 )

Gorgonia suberosa Ellis and Solander 1786:193 .

not Gorgonia suberosa Pallas, 1766:191 [= Suberogorgia suberosa ].

Titanideum suberosum Verrill, 1864b:39 .— Deichmann 1936:83; Plate 5 figs. 6–10.

Solanderia Frauenfeldii Kölliker, 1865:141 ; Plate 19 figs. 19–20, 22.

Titanideum frauenfeldii . — Bayer, 1961:77; Fig. 16a–d .— Cairns et al. 2002:33.

Material examined. SERTC S 426, 13 m, off Edisto Island , SC, June 4, 2004 . SERTC S2314 , 91.4 m, off Charleston , SC, March 31, 1979 . SERTC S 2655, 91 m, off Charleston SC, April 2, 1977 . SERTC S2654 , 24.4 m, off St. Helena Sound , SC, April 29, 2005 . SERTC S2660 , 72– 69 m, off Charleston , SC, March 28, 1981 .

Remarks. Titanideum frauenfeldii is a very common species occupying hardbottom habitats in the SAB. The colonies are moderately branched (or unbranched if small), with stiff, cylindrical, rod-like branches reaching 8 mm in diameter. The coenenchyme may appear smooth, slightly indented, or have slightly protruding polyp mounds. They vary from yellow to deep red in color. The ring of boundary canals separating the cortex and medulla is typical of this family and is generally very apparent when examining the branch in cross section. Also present is a layer of solenia, which divides the cortex into two layers— a thin, densely spiculated outer cortex and a thick, spongy inner cortex. The cortical sclerites consist of variable pink tuberculated spheroids and tuberculated branched bodies, and the medulla is filled with densely packed, colorless branching rods, most of which are oriented longitudinally.

Some colonies examined (S2314, S2655, S2660) for this work do not appear consistent with the typical T. frauenfeldii morphology. These colonies are not stiff, generally unbranched, and have protruding conical polyp mounds. The width of the stems range from 2–4 mm and the tips are somewhat inflated. Growing tips at both ends of some colonies suggests that they were unattached. The color of the colonies varies from pinkish orange to white. Spiculation of these colonies is consistent with the description of T. frauenfeldii in Bayer (1961) and distinguishes them from any other member of the western Atlantic Anthothelidae . Information on the nature of this morphological variation is not available, however all of the species examined for this work that display the variance were collected from 79–91 m, which is considerably deeper than some of the hardbottom habitats that the common morphotype of T. frauenfeldii occupies. This observation might suggest further investigation of the role of depth in the morphological differences exhibited by this species.

There are numerous lots of this species in the NMNH collections representing the shallow SAB.

Atlantic distribution: North Carolina to Cuba, north Gulf of Mexico, 13–293 m ( Deichmann, 1936; Bayer, 1961; NMNH collections; SERTC collections).

Figures

FIGURE 16. a) Virgularia presbytes; b) Sclerobelemnon theseus; c) dorsal streak of Virgularia presbytes; d) scale sclerites of Sclerobelemnon theseus; e) polyps of Stylatula elegans, needle sclerites indicated (modified from Bayer, 1958).

FIGURE 33. Titanideum frauenfeldii: A, sclerites (S2658); a–e) tuberculated branched bodies from cortex; f) triradiate from cortex; g) tuberculated spheroid from cortex; h-j) branching rods from medulla (scale bar for a-e = 0.02 mm; f, g = 0.01 mm; h-j = 0.05 mm); B, whole colony (preserved, height approximately 26 cm); C, live colony (in situ), showing expanded polyps.