Goniastrea

Milne Edwards and Haime, 1848, p. 495

Type Species

Astrea retiformis Lamarck, 1816, p. 265; Original Designation Milne Edwards and Haime, 1848, p. 495

Type Specimen: Holotype; MNHN IK-2010-693; Verified; Dry Preserved

Type Locality: 'les iles Seychelles' (Milne Edwards and Haime, 1849, vol. 12, p. 161) (Recent)

Classification

• Family: Merulinidae Verrill, 1865, p. 146

Synonyms

• Morchellastraea Alloiteau, 1941, p. 25
• Morchellastrea Reig Oriol, 1990, p. 24

Diagnosis

Colonial, with intracalicular budding only. Corallites monomorphic and discrete (1–3 centers) or uniserial; monticules absent. Walls generally fused, but moderate costate coenosteum (< corallite diameter) present in Goniastrea stelligera. Calice width small to medium (≤ 15 mm), with low to medium relief (≤ 6 mm). Costosepta generally not confluent. Septa in 3 cycles (24–36 septa). Free septa present, may be regular or irregular. Septa spaced ≥ 6 septa per 5 mm. Costosepta equal in relative thickness. Columellae trabecular and generally compact (1–3 threads), spongy (> 3 threads) in G. australensis, < 1/4 of calice width, and continuous among adjacent corallites. Paliform (uniaxial) lobes well developed, and may be present as septal (multiaxial) lobes. 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 to medium (≤ 0.6 mm) and tooth spacing narrow to medium (≤ 1 mm), with > 6 teeth per septum. Granules scattered on septal face; irregular in shape. Interarea palisade. Walls formed by strong abortive septa and partial septotheca; trabeculothecal elements may be present; dominant paratheca in G. australensis. Thickening deposits fibrous. Costa center clusters weak; ≤ 0.6 mm between clusters; medial lines weak. Septum center clusters weak; < 0.3 mm between clusters; medial lines weak. Transverse crosses absent. Columella centers clustered.

Description

'Multiplication par fissiparité. Murailles compactes et directement soudées entre elles. Cloisons finement denticulées, et portant des palis bien marqués. Columelle peu développée, mince à la partie inférieure des chambres.' (Milne Edwards and Haime, 1848, vol. 27: 495)

Comparisons

No apomorphies have been identified for Goniastrea, mainly due to the recovery of Goniastrea australensis outside of the Goniastrea clade. While the molecular trees generally show that Merulina and Scapophyllia are nested within the Goniastrea clade, morphological evidence indicates a sister relationship. It should be noted that they may not be as distinct as previously thought. In particular, the lack of apomorphies for Goniastrea among the suite of characters tested suggests that these genera share numerous traits, including all subcorallite characters analyzed here. Nevertheless, Goniastrea differs from Merulina and Scapophyllia in having mostly discrete corallites, costosepta that are not confluent across walls, well-developed epitheca and and low-moderate (tabular) endotheca. Goniastrea is also commonly confused with Favites spp. that have fused walls, as they do share most macromorphological characters. However, the former do not generally possess confluent costosepta, with fewer vesicular endotheca and internal lobes that are multiaxial (i.e. septal lobes). The more striking disparities are only observed via thin sections that show the presence of abortive septa and partial trabeculotheca only in Goniastrea, and on the other hand, paratheca, strong costa center clusters and transverse crosses in Favites.

Remarks

Goniastrea Milne Edwards and Haime, 1848, vol. 27: 495 accumulated new species gradually since the description of its type in the genus Astrea Lamarck, 1816 until as recent as the year 2000, in which three species were added (Veron, 2000). The genus was thought to have affinities with Favia and Favites (Chevalier, 1971; Veron et al., 1977), but molecular and morphological phylogenies have consistently placed the majority of its species within a clade that also includes Merulina and/or Scapophyllia (Huang et al., 2011, 2014; Arrigoni et al., 2012). Both data types support the sister relationship between the type species of Goniastrea, G. retiformis, and Astrea (Orbicella) stelligera Dana, 1846: 216, the latter conventionally regarded as an Indo-Pacific Favia (Veron, 2000, vol. 3: 102). This lends further support to the reasoning that coenosteum amount, moderate in this species but absent in Goniastrea, is an extremely homoplastic character, experiencing multiple changes near the tips of the tree. It is hereby synonymized as Goniastrea stelligera. Goniastrea australensis and G. deformis are not nested within other Goniastrea spp. but have been recovered near the main Goniastrea clade to varying degrees (Fukami et al., 2008; Huang et al., 2011; Arrigoni et al., 2012). Overall, the polyphyly of this genus ensures that the three remaining species—yet to be examined in a phylogenetic context—cannot be unequivocally placed (but see Huang, 2012). Despite forming at least two Goniastrea subclades that may not be sister groups, we consider it premature to make formal changes to these species until certainty of their positions increases appreciably. On the contrary, Goniastrea aspera Verrill, 1866: 32 and Favia palauensis Yabe and Sugiyama, 1936: 30 clearly belong in a separate taxon with affinities to Dipsastraea (molecular; Huang et al., 2011; Arrigoni et al., 2012) and Trachyphyllia (morphology; Huang et al., 2014). Accordingly, they are placed in Coelastrea Verrill, 1866: 32.

Distribution

• Caribbean; Late Cretaceous
• West Asia; Late Cretaceous
• Western Europe; Paleocene
• Southern Europe; Eocene
• Eastern Europe; Eocene
• Subsaharan Africa; Eocene
• Central America; Eocene
• Southern Europe; Oligocene
• Subsaharan Africa; Oligocene
• South Asia; Oligocene
• Central America; Oligocene
• South America; Oligocene
• Southeast Asia; Miocene - Pliocene
• Southern Europe; Miocene
• North Africa; Miocene
• Central Asia; Miocene
• South Asia; Miocene
• Australasia; Miocene
• Melanesia; Miocene
• Micronesia; Miocene
• Caribbean; Miocene
• West Asia; Miocene
• Southeast Asia; Miocene
• North Africa, Southeast Asia; Pliocene - Pleistocene
• North Africa; Pliocene
• East Asia; Pliocene
• Melanesia; Pliocene
• West Asia; Pliocene
• Southeast Asia; Pliocene
• East Asia; Pleistocene - Holocene
• North Africa; Pleistocene
• Subsaharan Africa; Pleistocene
• South Asia; Pleistocene
• East Asia; Pleistocene
• Australasia; Pleistocene
• Melanesia; Pleistocene
• Polynesia; Pleistocene
• West Asia; Pleistocene
• West Indian Ocean Islands; Pleistocene
• Southeast Asia; Pleistocene
• Indian Ocean; Recent
• Western Pacific; Recent
• Central Pacific; Recent
• South Asia; Holocene
• East Asia; Holocene
• Australasia; Holocene
• Melanesia; Holocene
• Micronesia; Holocene
• Polynesia; Holocene
• West Indian Ocean Islands; Holocene
• Southeast Asia; Holocene

This page has been in preparation since 04-Oct-2009 01:19

This version was contributed by Danwei Huang on 05-Feb-2014 22:12.

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