Ellisella elongata ( Pallas, 1766 ), 1841

Castro, C. B., Medeiros, M. S. & Loiola, L. L., 2010, Octocorallia (Cnidaria: Anthozoa) from Brazilian reefs, Journal of Natural History 44 (13 - 14), pp. 763-827 : 815-818

Ellisella elongata ( Pallas, 1766)

( Figures 1 , 20C,C′ ,C′′, 23)

For the synonymy previous to 1961, see Ellisella barbadensis and Ellisella elongata in Bayer (1961: 281–287, figs. 93–94.

Juncella barbadensis Duchassaing and Michelotti 1864: 22 , pl. 5, figs. 5, 6.

? Ellisella barbadensis: Tixier-Durivault 1970: 160 .

Ellisella elongata: Tixier-Durivault 1970: 160–161 ; Humann 1993: 68–69 (field guide); Hetzel and Castro 1994: 97 (photos only).

Ellisella barbadensis: Humann 1993: 66–67 (field guide).

Diagnosis

Colonies unbranched or with up to several branches. Branches long, when present. Sclerites of coenenchyme as capstans and dumb-bells (up to 0.09 mm); proportions of these sclerites vary from colony to colony and depending on position in a single colony. Calyx with same sclerites as coenenchyme, as well as double-cones (up to 0.09 mm). Simple or multiple series of polyps near tips of branches. Coenenchymal mounds from absent to conspicuous, directed towards distal ends of branches (emended from Bayer 1961: 281, 285, to accommodate characters from the new synonymy).

Description

Colonies up to 50 cm long (one fragment up to 59 cm). Colonies and fragments from flagelliform ( Figure 20C ) to having several, long ramifications (up to 14). Basis of colonies as disk that spreads on substrate. Trunk and lower parts of branches cylindrical or flattened, thick (up to 6 mm in diameter). Branches laterally flattened (this flattening being less conspicuous in larger fragments). Branch diameters with calyx up to 1.9 × 1.3 mm near basis (in some fragments up to 4.9 × 4.8 mm) and 0.9 × 0.7 mm near tip of the branch (10 mm). Branches from very flexible to relatively rigid, usually long, arising in upwardly acute angles (occasionally almost at right angles and soon turning upwards). Diameter of branch decreases gradually, without any rough variations. Lateral branches thinner than branch where they originated. Distal ends of branches cylindrical or flattened, up to 2.5 × 1.7 mm thick at a distance of about 1 cm from tip; tips with diameter decreasing rapidly, ending acutely or, occasionally, bluntly. Trunk without polyps, with scattered polyps or with polyps in longitudinal series. Branches may have two bands of one or two longitudinal series of polyps, each or these may be densely distributed in two opposite bands with oblique series of three to seven polyps in proximal part of branches ( Figure 20C′ ). Two bands without polyps between rows or bands, which may have only one longitudinal groove and be more or less conspicuous. On the distal part of branches (distance over 50 mm long), polyps also in two bands, but in oblique series of two to three polyps ( Figure 20C ′′), occasionally single rows for short distances (five to six polyps); there are two bands without polyps between them, which may be absent or inconspicuous, or may have one longitudinal groove. One colony with one narrow band without polyps and one band with polyps, the latter three-quarters of the colony circumference, with five to seven polyps in each oblique series. Contracted polyps completely retracted into coenenchyme, forming no coenenchymal mounds, as little elevations on coenenchyme ( Figure 20C′ ), or well developed, slightly turned to distal ends of branches ( Figure 20C ′′). Colonies may also have expanded polyps, turned upwards, longitudinally appressed or apart from coenenchyme. Sclerites of coenenchyme dumb-bells, ornamented with densely distributed tubercles, and capstans with little more sparse ornamentation (both up to 0.09 mm). No remarkable differences between sclerites from outer and middle layers of coenenchyme ( Figure 23A′ F). Sclerites from coenenchymal mounds or near polyp bases as those from coenenchyme (dumb-bells and capstans, up to 0.09 mm), and double-cones with sparser tuberculated ornamentation (up to 0.1 mm) ( Figure 23G–I ). In axial sheath, sclerites as those from coenenchyme, but with less developed ornamentation (up to 0.08 mm) ( Figure 23J–L ). Polyps with slender rods (up to 0.07 mm) ( Figure 23M ), some colonies also with double-cones like these from the calyx, but with more scattered ornamentation (up to 0.12 mm), in column and tentacles. Colonies and sclerites colour white to dark or light orange. Polyps and their sclerites white or same colour as colony.

Material

Haiti: [MNRJ 1250 (= USNM 74917)]. Brazil: Amapá (USNM 50899); Pará [MNRJ 01249 (= USNM 50904), USNM 50902]; Bahia (MNRJ 01841); Espírito Santo (MNRJ 4132, 04779, 04801, 04802, 04814, 04825, 05002); Rio de Janeiro (MNRJ 00501, 00503, 01357, 01466, 01525, 04816, 04900, 04904, 05934, 05975); São Paulo [MNRJ 00502 (= USNM 73427)]; Rio Grande do Sul (MNRJ 01523, 01524).

Comparative material

Scirpearia grandis Verrill, 1901 – “ TYPE ” – off North Rock , Bermudas [ MCZ 4740 (66m)].

Type depository

According to Simpson (1910) and Deichmann (1936), the original type is lost. Simpson (1910: 326) found a specimen from the Museum of the Royal College of Surgeons (Reg. 184), belonging to a very ancient collection (Hunterian Collection), and labelled as “ Gorgonia elongata ”, which he explicitly designated as a neotype (“regard this specimen as the type”). Deichmann (1936) uses the same material as reference, quoting Simpson’s designation. As Simpson’s work fulfils all requisites of article 75 from the International Code on Zoological Nomenclature, we recognize here Simpson’s neotype indication.

Type locality

“Oceanus Atlanticus” ( Pallas 1766); “West Indies” ( Simpson 1910).

Geographic distribution

Western Atlantic: east coast of Florida (21–38 m), north of Gulf of Mexico (75–77 m) ( Bayer 1961); Antilles (168–480 m) ( Deichmann 1936); north of South America south to off the Amazon (137–201 m) ( Bayer 1959), eastern and south-eastern Brazil: from Alagoas (c. 10° S) ( Tixier-Durivault 1970) to Rio Grande do Sul (c. 30° S) States. Oceanic areas in the South Atlantic: Jaseur Seamount, Columbia Seamount, Almirante Saldanha Seamount, and Martin Vaz Island ( Figure 1 ).

Remarks

The Brazilian specimens of Ellisella were previously included in two species: E. barbadensis and E. elongata (see Bayer 1959). Deichmann’s drawings of the sclerites show only dumb-bells and double-cones for E. barbadensis ( Deichmann, 1936: pl. 24, figs. 1–19), whereas they also show capstans, besides these forms, for E. elongata ( Deichmann 1936: pl. 24, figs. 46–48). Accordingly, the presence of capstans should, therefore, differentiate these species. Bayer (1959: figs. 9–12; 1961: figs. 93–94) endorsed Deichman’s opinion, mentioning that “the ‘capstan’ form of the cortical sclerites differentiates Ellisella elongata from E. barbadensis ...” ( Bayer 1961).

However, the number of available colonies from the South Atlantic has been considerably enlarged in the last 10 years, making it possible to examine larger series. According to this material, it is impossible to indicate any character to differentiate these two species based on the differences indicated by Deichmann (1936), Bayer (1959, 1961), or any other authors. The capstans and dumb-bells are present together in most colonies. Also, groups of specimens with similar morphological traits (such as colony and polyps shapes) showed variation in the dominance between capstans, dumb-bells and intermediate forms in different parts of the colonies. This great variability of forms of sclerites in the colonies here observed show that this character is not enough to separate E. barbadensis from E. elongata . Accordingly, it seems to be more reasonable to keep all the studied material in a single species.

Figures

Figure 1. Map of distribution of reef octocorals in different regions off the Brazilian coastline. The Espírito Santo State area (*) includes the Vitória- Trindade seamount chain. “BA Sector” refer to a division of reef areas in Bahia State by Leão (1996).

Figure 20. Olindagorgia gracilis (Verrill, 1868a) (MNRJ 01837): (A) colony, (A′) branches. Phyllogorgia dilatata (Esper, 1806) (MNRJ 00478): (B) colony, (B′) branches. Ellisella elongata (Pallas, 1766) (MNRJ 1841): (C) fragment, (C′) closer view near basis of fragment, (C′′) closer view near distal end of fragment. Scale bars: A–C, 2 cm; A′–C′, C′′, 5 mm.

Figure 23. Sclerites of Ellisella elongata (Pallas, 1766) (MNRJ 1841): (A) outer layer of coenenchyme, near distal end of colony; (B) outer layer of coenenchyme, middle region of colony; (C) outer layer of coenenchyme, near basis of colony; (D) middle layer of coenenchyme, near distal end of colony; (E) middle layer of coenenchyme, middle region of colony; (F) middle layer of coenenchyme, near basis of colony; (G) coenenchymal mounds, near distal end of colony; (H) coenenchymal mounds, middle region of colony; (I) coenenchymal mounds, near basis of colony; (J) axial sheath, near distal end of colony; (K) axial sheath, middle region of colony; (L) axial sheath, near basis of colony; (M) polyp.