Ehrenberg, 1834, p. 323

Type Species

Maeandra (Platygyra) labyrinthica Ehrenberg, 1834, p. 323 = Maeandra (Platygyra) lamellina Ehrenberg, 1834; Original Designation Ehrenberg, 1834, p. 323

Type Specimen: Syntype; ZMB Cni682; Verified; Dry Preserved

Type Locality: Red Sea (Recent)

Many authors (e.g., Veron, Pichon, Wijsman-Best, 1997; Chevalier, 1975) indicate "Platygyra labyrinthica Ehrenberg 1834 (non Madrepora labyrinthica Ellis and Solander 1786) = Madrepora daedalea Ellis and Solander 1786" to be the type species of Platygyra. However, examination of one of Ehrenberg's specimens of P. labyrinthica indicates that it is equivalent to Platygyra lamellina Ehrenberg, 1834, p. 323, see Matthai (1928), pl. 65. Note: Matthai (1928) indicates Cni669 as the holotype of "Maeandra (Platygyra) labyrinthica leptochila", and Cni682 and Cni683 as specimens of "Maeandra (Platygyra) labyrinthica". No specimens of "Maeandra (Platygyra) labyrinthica pachychila" are figured (although the holotype may be NHM ZD 1884.10.20.1, which is figured for Brachymeandrina).




Colonial, with intracalicular budding only. Corallites monomorphic and mostly uniserial, but may also be discrete (1–3 centers); monticules absent. Walls fused. Calice width medium (4–15 mm), with medium relief (3–6 mm). Costosepta confluent. Septa in < 3 cycles (< 24 septa). Free septa present but irregular. Septa spaced 6–11 septa per 5 mm. Costosepta equal in relative thickness. Columellae trabecular and spongy (> 3 threads), < 1/4 of calice width, and continuous among adjacent corallites. Paliform (uniaxial) lobes absent. Epitheca well developed and endotheca low-moderate (tabular). Tooth base at mid-calice circular. Tooth tip at mid-calice irregular; tip orientation perpendicular to septum. Tooth height low (< 0.3 mm) and tooth spacing medium (0.3–1 mm), with > 6 teeth per septum. Granules aligned on septal face, perpendicular to septal margin; weak (rounded). Interarea palisade. Walls formed by dominant trabeculotheca and partial septotheca; abortive septa absent. Thickening deposits fibrous. Costa center clusters weak; < 0.3 mm between clusters; medial lines weak. Septum center clusters weak; < 0.3 mm between clusters; medial lines strong. Transverse crosses absent. Columella centers aligned.


'Stolonibus in margine stirpis repentibus, in disco nullis.' (Ehrenberg, 1834: 323)


Platygyra is moderately supported on the morphology tree, with the synapomorphy of spongy columellae (> 3 threads), distinguishing it from closely-related Australogyra (compact; 1–3 threads) and Leptoria phrygia (lamellar). Leptoria irregularis has spongy columellae however, and so the character state is recovered as a plesiomorphy on the molecular tree, which samples this species. It is not easily confused with Platygyra because of its small (< 4 mm width) and shallow (< 3 mm depth) calices. Platygyra and Australogyra share all other characters, although the latter's ramose growth form makes its colonies easily separable from those of Platygyra. Molecular data would further clarify the validity of Australogyra as a genus.


The taxonomic history of Platygyra Ehrenberg, 1834: 323 is extremely convoluted. It was described as a subgenus of Maeandra Oken, 1815: 68 with five species, the first of which being M. (Platygyra) labyrinthica Ehrenberg, 1834: 323, to which he referenced as synonyms Meandrina labyrinthica (Lamarck, 1816: 246), Madrepora labyrinthiformis Linnaeus, 1758: 794 and Madrepora labyrinthica Ellis and Solander, 1786: 160, pl. 46: figs 3, 4. In order to clarify this, Brüggemann, 1879: 571 fixed Madrepora labyrinthica (Ellis and Solander, 1786: 160) as the type. This is problematic because the specimens described by Linnaeus, 1758: 794 and Ellis and Solander, 1786: 160 were derived from the Atlantic (Matthai, 1928: 110). More recently, Chevalier, 1975: 122 and Veron et al., 1977: 98 have treated Madrepora daedalea Ellis and Solander, 1786: 163, pl. 46: fig. 1 as synonymous to Ehrenberg's definition of the type species. However, examination of one of Ehrenberg's syntypes of Maeandra (Platygyra) labyrinthica (ZMB Cni 682) strongly suggests that it is equivalent to the second (of five) species he listed, M. (Platygyra) lamellina Ehrenberg, 1834: 323. In accordance with Vaughan and Wells, 1943: 169, Wells, 1956: F402 and Wells, 1986: 49, we regard P. lamellina as the type species of Platygyra. The genus has consistently been recovered as a well-supported clade in molecular phylogenies (Fukami et al., 2004, 2008; Huang et al., 2009, 2011; Arrigoni et al., 2012). There is a general lack of genetic variation among Platygyra spp. (Miller and Benzie, 1997; Lam and Morton, 2003), and where there is differentiation, morphotypes do not necessarily correspond with genotypes (Mangubhai et al., 2007), partly caused by large phenotypic variation within species and high morphological overlap among species (Miller, 1992, 1994; Mangubhai et al., 2007). Platygyra's closest relative appears to be Leptoria (together as subclade G) but they are genetically distinguishable from each other. Australogyra has not been sampled for molecular phylogenetic work, but based on morphological similarities with Platygyra even at the subcorallite level, they are expected to be closely related.


  • North Africa; Paleocene
  • Micronesia; Eocene
  • South America; Eocene
  • Southeast Asia; Oligocene - Miocene
  • Western Europe; Oligocene
  • West Asia, Southeast Asia; Miocene - Pliocene
  • Western Europe; Miocene
  • Southern Europe; Miocene
  • South Asia; Miocene
  • Melanesia; Miocene
  • Caribbean; Miocene
  • Southeast Asia; Miocene
  • North Africa, Southeast Asia; Pliocene - Pleistocene
  • North Africa; Pliocene
  • East Asia; Pliocene
  • Melanesia; Pliocene
  • Polynesia; Pliocene
  • West Asia; Pliocene
  • Southeast Asia; Pliocene
  • East Asia, Southeast Asia; Pleistocene - Holocene
  • Subsaharan Africa; Pleistocene
  • South Asia; Pleistocene
  • East Asia; Pleistocene
  • Australasia; Pleistocene
  • Melanesia; Pleistocene
  • Micronesia; Pleistocene
  • Polynesia; Pleistocene
  • West Asia; Pleistocene
  • Southeast Asia; Pleistocene
  • Indian Ocean; Recent
  • Western Pacific; Recent
  • Central Pacific; Recent
  • East Asia; Holocene
  • Australasia; Holocene
  • Melanesia; Holocene
  • Micronesia; Holocene
  • Southeast Asia; Holocene
Source: Paleobiology Database (accessed June 19th, 2012), Veron (2000). Historical distribution: Eocene-Recent., Europe-IndoPacific (Wells, 1956). Distribution compiled by Matthew Tibbits. Recent: Platygyra is widely distributed on reefs of the Indo-Pacific, present as far east as the Tuamotu Archipelago in the southern hemisphere (Glynn et al., 2007), but absent eastwards from Hawai'i in the north.

This page has been in preparation since 26-Oct-2009 22:20

This version was contributed by Danwei Huang on 05-Feb-2014 23:41.

Page authors are: Ann Budd Danwei Huang. Please contact the editor if you would like to contribute to the diagnosis of this taxon.

The editor is: Ann Budd

Syntype of Platygyra labyrinthica Ehrenberg
Syntype of Platygyra labyrinthica Ehrenberg