Fromia Gray 1840

Mah, Christopher L., Kogure, Yoichi, Fujita, Toshihiko & Higashiji, Takuo, 2024, New Taxa and Occurrences of Mesophotic and Deep-sea Goniasteridae (Valvatida, Asteroidea) from Okinawa and adjacent regions, Zootaxa 5403 (1), pp. 1-41 : 8-9

Fromia Gray 1840

Fromia Gray 1840: 286 ; Fisher 1919: 373; H.L. Clark 1921: 38; Rowe & Gates 1995: 81; Mah & Foltz 2011: 771, 779, 782 Celerina A.M. Clark 1967: 193 ; Rowe & Gates 1995: 80

Austrofromia H.L. Clark 1921: 48 ; Rowe 1989: 291; Rowe & Gates 1995: 81.

Diagnosis

Body strongly stellate (R/r=3.5–5.0), arms elongate, strap-like to triangular in shape. Interradial arcs acute. Arm rectangular in cross-section. Abactinal plates abutted, ranging ranging from flat to convex, covered with a distinct continuous granular cover. Marginal plates broadly quadrate in outline forming discrete frame around abactinallateral outline of body. Marginal plate surface covered by continuous granular cover. Actinal region small, with granule-covered surface. Papulae present at marginal and actinal plate contact. Furrow spines blunt, relatively few, with variable subambulacral armature. (based on Mah 2018).

Comments

Fromia includes 16 species which distributed primarily throughout the Indo-Pacific with some species present across a broad range. Some species, such as Fromia monilis , show widespread occurrence from the central and south Pacific to the far western Indian Ocean.

No Atlantic species are known. Fromia has been recorded from historically shallow, reef habitats (e.g. Clark and Rowe, 1971, A.M. Clark 1993). However, more recent accounts have indicated mesophotic occurrence in some species, such as F. milleporella in 0–86 m ( Mah 2018).

Fromia were historically placed within the Ophidiasteridae until molecular data clarified its position within the Goniasteridae ( Mah & Foltz 2011) . This revision also synonymized Celerina A.M. Clark 1967 with Fromia .

Many of the species terms for Fromia either represent clusters of similar species or highly variable complexes within single highly variable species (e.g. Fromia monilis ). Molecular data has done much to illustrate cryptic species complexes within described species (e.g. Astropecten, Zulliger & Lessios, 2010 ). Broadly based revisionary work is needed for Fromia , see comments below.

Eight species of Fromia are known from Japanese waters, six are recorded from mesophotic depths. Rowe and Gates (1995) record the depth range of Fromia indic a Perrier 1869 as 0–44 m, suggesting that it also might be present at mesophotic depths in Japanese waters.

Fromia ’s recent placement in the Goniasteridae precludes any clear historical affinities with established goniasterid genera.However Fromia does demonstrate morphological affinities with goniasterid-like Ophidiasteridae , such as Narcissia , which at small sizes shows a distinct peripheral marginal series and abutted abactinal plates with a continuous granular cover.