Fimbriaphyllia Veron & Pichon, 1980

Arrigoni, Roberto, Stolarski, Jarosław, Terraneo, Tullia I., Hoeksema, Bert W., Berumen, Michael L., Payri, Claude, Montano, Simone & Benzoni, Francesca, 2023, Phylogenetics and taxonomy of the scleractinian coral family Euphylliidae, Contributions to Zoology 92 (2), pp. 130-171 : 154-156

Fimbriaphyllia Veron & Pichon, 1980

(figs. 1G–O, 9)

Synonyms: Botryphyllia Shirai, 1980 ; Euphyllia (Fimbriaphyllia) Veron & Pichon, 1980 .

Type species: Euphyllia (Fimbriaphyllia) ancora Veron & Pichon, 1980 ; holotype: bmnh 1983.9.27. 6(illustrated in Veron &Pichon, 1980: figs. 623, 628); paratype: gl 4152 (Queensland Museum, Brisbane, Australia; see Veron & Wallace, 1984: 473–474); type locality: Jewell Reef, Great Barrier Reef ( Australia).

Original description: ‘Coralla are flabelloid to flabello-meandroid depending mainly on size. Small, flabelloid coralla initially develop a crescentic form from which irregular branches develop. Larger coralla are dome-shaped with long sinuous to straight valleys which are usually interconnected. The width of the valleys varies greatly, depending on environmental conditions and the corallum size. Large coralla, which are mostly restricted to protected, partly turbid water, usually have narrow valleys. Coralla in early stages of development have wide valleys, usually with fluted margins. They are in the process of relatively rapid lateral growth and hence valleys are wide and thecae often greatly thickened by dissepiments. The development of the septa is also variable and also depends on environmental conditions and corallum size. Large coralla and those from turbid biotopes have small, relatively regular septa which are only slightly exsert and which are usually in three regular orders with an abortive fourth order. Small coralla and those from more exposed biotopes have more irregular septa. Some may be exsert up to 1 cm, others only fine ridges with orders often difficult to distinguish. All septa are glabrous or finely dentate and frequently have finely serrated margins. The larger septa extend to, or nearly to, the valley axis or calice centre and have vertical or subvertical inner margins which may be folded or curved towards the centres. Some septa have broad inner margins which may become slightly dentate. There are no columellae. The development of the costae varies greatly depending on the degree to which the septa are exsert and the degree of development of the exothecal dissepiments. In some coralla, the costae appear only as fine striations, in others they are lobed or form spines which, as with E. glabrescens , may develop into buds. Some coralla show pronounced development of endothecal dissepiments but this is usually restricted to small coralla or those growing in exposed biotopes where lateral growth is pronounced ( Veron & Pichon, 1980: 352, 354).

Diagnosis: Colonial. Budding intracalicular and extracalicular. Corallites monomorphic and discrete. Colonies phaceloid. Calice of relief high (> 6 mm) and width large (> 15 mm). Septa in Ẑ 4 cycles (Ẑ 48 septa). Free septa regular. Septal spacing wide (> 11 septa per 5 mm). Costosepta unequal in relative thickness. Columellae absent. Paliform lobes absent. Endotheca abundant (vesicular). Septal faces delicately grainy, with low but pointed granulae arranged in rows parallel to septal margin. Bundles of td fibers not well delineated, perpendicular to septal surface. Closely spaced (zig-zag mid-septal zone) rads. Polyp tentacles fully extended at daytime, of shape complex.

Species included: Fimbriaphyllia ancora ( Veron & Pichon, 1980) ; Fimbriaphyllia divisa ( Veron & Pichon, 1980) ; Fimbriaphyllia paraancora ( Veron, 1990) ; Fimbriaphyllia paradivisa ( Veron, 1990) ; Fimbriaphyllia yaeyamensis ( Shirai, 1980) .

Taxonomic remarks:Based on colony growth form, Veron & Pichon (1980) established two subgenera within the genus Euphyllia , namely Euphyllia and Fimbriaphyllia . Originally, the subgenus Fimbriaphyllia included E. (Fimbriaphyllia) ancora and E. (Fimbriaphyllia) divisa , while the subgenus Euphyllia was composed of E. (Euphyllia) cristata and E. (Euphyllia) glabrescens ( Veron & Pichon, 1980). Subsequently, Veron (2000) maintained two distinct groups within the genus Euphyllia , separating the phaceloid species from the flabello-meandroid ones. Molecular data showed that the species traditionally ascribed to Euphyllia were separated in two major lineages (Fukami et al., 2008; Lin et al., 2011; Akmal et al., 2017; Luzon et al., 2017, 2018). Luzon et al. (2017, 2018) demonstrated that these two groups can be distinguished based on the polyp morphology and reproductive traits and not on the colony growth form. As such, Luzon et al. (2017, 2018) resurrected Fimbriaphyllia as a valid genus to be composed of five species, namely F. ancora , F. divisa , F. paraancora , F. paradivisa , and F. Downloaded from Brill.com 08/29/2023 05:29:52PM via free access yaeyamensis . Our morpho-molecular results are in agreement with those presented by Luzon et al. (2017, 2018) and previous molecular phylogeny reconstructions (Fukami et al., 2008; Lin et al., 2011; Akmal et al., 2017).

Morphological remarks: Fimbriaphyllia has been traditionally confused with Euphyllia because of their macromorphological resemblance. The morphological characters that separate the two genera are described in the morphological remarks section of Euphyllia , with a particular focus on the columella structure and polyp shape as diagnostic characters. Additionally, septal faces are delicately grainy, with the low but pointed granulae arranged in rows parallel to septal margin, which is a unique micromorphological/microstructural feature within the family Euphylliidae .

Distribution: Fimbriaphyllia is widely distributed on the reefs of the Indian and Pacific Oceans, occurring from the Red Sea and East Africa as far east as Marshall Islands in the Northern Hemisphere and Fiji in the Southern Hemisphere ( Veron, 2000; Glynn et al., 2007; Obura, 2012; Richards & Beger, 2013; Huang et al., 2015; Veron et al., 2015; Eyal et al., 2016; DeVantier & Turak, 2017; Berumen et al., 2019; Montgomery et al., 2019).