Plexaurella grandiflora Verrill, 1912

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 : 794-796

Plexaurella grandiflora Verrill, 1912

( Figures 1 , 12B,B′ , 12C,C′, 14)

For the synonymy previous to 1961, see Bayer (1961: 173–175, text-fig. 52, pl. VI, fig. 5).

Plexaurella grandiflora: Hetzel and Castro 1994: 93 (photos only); Medeiros and Castro 1999: 11–12.

Diagnosis

Colonies dichotomously branching ( Figure 12B,C ). Branches can be thickened at extremities ( Figure 12B′ ,C′). Coenenchymal mounds from absent to well developed (conical or tubular), sometimes bilabiate. Sclerites of outer layer of coenenchyme butterflies (up to 0.10 mm long), often asymmetricallly developed, with rays ornamented with well-developed tubercles; tentacles with flat rods reaching 0.07 mm long. Middle layer mainly with butterflies (up to about 0.20 mm long); also triradiates and spindles (up to 0.40 mm long), either straight or bent at the waist, with welldeveloped and densely distributed tubercles ( Figure 14 ) (emended from Bayer 1961: 174 to include forms without coenenchymal mounds, to indicate well-developed tubercles in outer layer butterflies, and to incorporate minor adjustments in sclerite sizes).

Description

For a complete description see Bayer (1961: 173–175, text-fig. 52, pl. VI, fig. 5).

Material

Brazil: Paraíba (MNRJ 00446, 01273; UFPb 397); Pernambuco (YPM 4503; MNRJ 02754); Alagoas (MNRJ 00445, 02752); Bahia (YPM 1597, 1598, 4501, 4502; MNRJ 00157, 00435, 00436, 01274, 01397, 01988, 02199, 02584, 02726, 02861, 04002, 04342, 04584, 04585, 04586, 04587; UFPb 275, 278, 282, 289, 294, 298); Espírito Santo (MNRJ 00431, 00432, 00433, 00437, 00438, 00439, 00441, 00442, 00635, 00639, 01148, 01149, 01344, 01987, 03961, 04589); Rio de Janeiro (MNRJ 00444).

Type depository

Peabody Museum of Natural History , Yale University, New Haven, CT, USA ( YPM 4501 ) .

Type locality

“Mar Grande, Brazil ” ( Verrill 1912: 361).

Geographic distribution:

Endemic in the Brazilian littoral (recorded from Paraíba to the border of Espírito Santo with Rio de Janeiro States) ( Figure 1 ).

Remarks

Castro (1989) discussed the high variability in the colonial morphology of P. grandiflora . Its sclerites and colonial morphology are very similar to those of P. dichotoma . The main character that differentiates both species would be the presence of small antlers in P. dichotoma and the absence or extreme rarity of these sclerites in P. grandiflora . The same author, after the examination of Verrill’s type specimens of P. pumila , P. cylindrica , P. braziliana and P. verrucosa , and because of the overlap of several taxonomic characters, proposed the synonymy of P. pumila and P. grandiflora , and confirmed the synonymy of the other species with P. grandiflora .

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 12. Plexaurella dichotoma (Esper, 1791) (MNRJ 00980): (A) colony, (A′) branch. Plexaurella grandiflora Verrill, 1912 (MNRJ 04342 – long branches): (B) colony, (B′) branch. Plexaurella grandiflora Verrill, 1912 (MNRJ 02752 – short branches): (C) colony, (C′) branch. Plexaurella regia Castro, 1989 (MNRJ 02748): (D) colony, (D′) branch. Scale bars: A–D, 2 cm; A′–D′, 5 mm.

Figure 14. Sclerites of Plexaurella grandiflora Verrill, 1912 (YPM 4503 – holotype of Plexaurella verrucosa Verrill, 1912): (A) outer layer of coenenchyme; (B) middle layer of coenenchyme; (C) axial sheath.