Studer, 1878, p. 262
Isopora was elevated to genus from a subgenus of Acropora by Wallace et al 2007, based on consistent genetic, reproductive and morphological differences between the two genera. For nomenclatural and taxonomic history, see: Wallace, C. C , Chen, C. A. C. , Fukami, H. and Muir, P. R. (2007) Recognition of separate genera within Acropora based on new morphological, reproductive and genetic evidence from A. togianensis, and elevation of the subgenus Isopora Studer, 1878 to genus (Scleractinia: Astrocoeniidae; Acroporidae). Coral Reefs 26: 231-239. For original subgenus description see: Studer, T. 1878 Zweite Abtheilung der Anthozoa Polyactinia, whelche wahrend der Reise A. M. S. Corvette Gazelle um die gesmmelt wurden. Monatsberichte der Königlich Preussischen der Wissenschaften zu Berlin 1878:525-550.
Astrea palifera Lamarck, 1816 p. 262; Subsequent Designation
Type Specimen: Holotype; MNHN Z301a; Verified; Dry Preserved
Type Locality: “Southern Ocean”
Isopora palifera designated as type species of subgenus Isopora of Acropora, by Veron and Wallace, 1984. See: p. 153 in: Veron, J. E. N. and Wallace, C. C. (1984). Scleractinia of Eastern Australia. Part V. Family Acroporidae. Australian Institute of Marine Science Monograph Series 6. Astrea palifera is senior synonym of Madrepora labrosa Dana 1846, referenced first by Studer, 1878 describing Isopora without designation of a type species.
Acroporidae which are cuneiform, encrusting, or ramose, with multiple axial or leading corallites, or a tendency towards more than a single axial corallite, per branch, and numerous radial corallites. Coenosteum with elaborated meandroid spinules; columella and dissepiments absent. Polyps hermaphrodite, with oocytes and testes (spermaries) borne on separate mesenteries, mature oocytes contained in stalked extensions of the mesenterial filaments. Reproduction by release of sperm followed by internal fertilization and larval development.
Colony sturdy, branches formed around numerous sxial corallites (I. palifera, I. cuneata, I. ginsbergi) or with one main axial and supplementary axials around the tip (I. breuggemanni, I. togianensis, I. curacaoensis) or no branches formed (I. crateriformis); growth usually indeterminate, sometimes leading to colonies which cover many square metres; radial corallites tubular with dimidiate opening, or conical. Coenosteal spinules distinctive, elaborated meandroid: additional coenosteal decoratiions developed in some species (e.g. I. togianensis, I. crateriformis) and some circumstances (e.g. sometimes in I. palifera).
Although axial corallites may be present in Isopora, they are not as strongly differentiated from radial corallites as in Acropora: there may be multiple axials forming club-shaped or cuneate branches (I. palifera, I. cuneata, I. ginsbergi (F)), single axials forming branches, but with supplementary axials at branch tips (I. brueggemanni, I. togianensis, I. curacaoensis (F)), or no axials present (I. crateriformis). Acropora and Isopora differ in gametic morphology, ova and spermaries being born within mesenterial filaments in Acropora and on stalks in Isopora, also in reproductive mode, Acropora being a spawner versus Isopora a brooder oviparous versus viviparous). Cuneate branches similar to those of I. palifera are seen in fossil Astreopora (A. goethelsi and A. antiguensus Vaughan, 1919).
For discussion of the role of the axial corallites and other differences between Isopora and Acropora see: Wallace, C. C , Chen, C. A. C. , Fukami, H. and Muir, P. R. (2007) Recognition of separate genera within Acropora based on new morphological, reproductive and genetic evidence from A. togianensis, and elevation of the subgenus Isopora Studer, 1878 to genus (Scleractinia: Astrocoeniidae; Acroporidae). Coral Reefs 26: 231-239.
For fossil record in the Caribbean see: Budd, A. F. and Wallace, C. C. (2008) First record of the Indo-Pacific reef coral genus Isopora in the Caribbean region: two new species from the Neogene of Curacao, Netherlands Antilles. Palaeontology, 51: 1387–1401. Wallace, C. C. and Budd, A. F. (2009) Mirror-image fossils reveal colony form of extinct Curaçao Isopora. Coral Reefs 28: 715.
- Caribbean; Miocene - Pliocene
- Australasia; Pliocene - Pleistocene
- Indian Ocean; Recent
- Western Pacific; Recent
- Central Pacific; Recent
This page has been in preparation since 02-Jun-2007 12:36
This version was contributed by Carden Wallace on 16-Mar-2010 05:43.
Page authors are: Carden Wallace. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Ann Budd