Paramontastraea
Huang and Budd, 2014
The name sets this taxon in contrast to other species present in both Indo-Pacific and Atlantic reefs that were classed according to superficial similarities in the genus Montastrea (sensu Veron, 1986: 502, 2000, vol. 3, p. 212). The latter is now restricted in modern scleractinians to the phylogenetically distinct Atlantic species, Montastraea cavernosa.
Type Species
Paramontastraea salebrosa Nemenzo, 1959, p. 92, pl. 1, p. fig. 2; Original Designation Huang and Budd, 2014
Type Specimen: Holotype; UPMSI C-192; Verified; Dry Preserved
Type Locality: Puerto Galera, the Philippines (Recent)
Classification
Diagnosis
Colonial, with mostly extracalicular budding (Paramontastraea peresi also has intracalicular budding). Corallites monomorphic and discrete (1–3 centers); monticules absent. Coenosteum may be spinose, moderate amount (< corallite diameter). Walls fused in P. peresi. Calice width medium (4–15 mm), with low relief (< 3 mm) but slightly higher in P. peresi. Costosepta not confluent. Septa in 3 cycles (24–36 septa); 4th cycle sometimes present in P. peresi. Free septa regular. Septa spaced > 11 septa per 5 mm. Costosepta unequal in relative thickness. Columellae trabecular and spongy (> 3 threads), < 1/4 of calice width, and discontinuous among adjacent corallites. Paliform (uniaxial) lobes well developed. Epitheca well developed and endotheca low-moderate (tabular). Tooth base at mid-calice circular. Tooth tip at mid-calice irregular; tip orientation multiaxial. Tooth height low (< 0.3 mm) and tooth spacing narrow (< 0.3 mm), with > 6 teeth per septum. Granules scattered on septal face; irregular in shape. Interarea smooth. Walls formed by dominant septotheca and partial paratheca; abortive septa absent. Thickening deposits fibrous. Costa center clusters weak; 0.3–0.6 mm between clusters; medial lines weak. Septum center clusters weak; < 0.3 mm between clusters; medial lines weak. Transverse crosses absent. Columella centers clustered.
Comparisons
Paramontastraea is only supported by their well-developed paliform lobes as a synapomorphy. Although genetically closest to Echinopora, this new genus can be distinguished based on its reduced coenosteum (< corallite diameter) and columellae (< 1/4 of calice width), strong paliform lobes, narrower tooth spacing (< 0.3 mm), as well as septotheca (dominant) and paratheca without abortive septa. It instead forms a clade with Cyphastrea and Orbicella on the morphology tree, but these have smaller corallites with less spongy columellae and do not develop strong paliform lobes.
Remarks
Paramontastraea was established based on a combination of molecular and morphological evidence from Huang et al. (2011, 2014) and Arrigoni et al. (2012). The three members of this genus had never been examined in the same context, but their positions on the Merulinidae phylogeny are well established. The type species was first examined and shown to be sister to Echinopora by Huang et al. (2011) in subclade XVII-I with high statistical support. This association runs counter to conventional taxonomy at that time, and is supported by few unique morphological traits (e.g. spinose coenosteum). Arrigoni et al. (2012) subsequently recovered a similar topology, but with Echinopora mammiformis more closely related to Plesiastrea salebrosa Nemenzo, 1959: 92 than to its congenerics. The tree also shows a striking association—that of Favites peresi Faure and Pichon, 1978: 107 as sister species to P. salebrosa. Although this particular relationship is not well supported, the clade of Echinopora + P. salebrosa + F. peresi appears stable. As expressed by Arrigoni et al. (2012), F. peresi has been placed in Favites and Goniastrea before, but their tree indicates that neither of these genera has close affinity. The morphological phylogeny lends some support to this affiliation, as P. salebrosa and Montastrea serageldini Veron, 2000 vol. 3: 213 are recovered as sister species within the clade of Echinopora, Cyphastrea and Orbicella. By integrating across these diverse results, it has been inferred that P. salebrosa, F. peresi and M. serageldini are close relatives and were thus placed in the new genus Paramontastraea. The alternative solution to synonymize them as Echinopora based on the molecular phylogeny was also considered, but they are morphologically more similar to Cyphastrea + Orbicella. Further investigation is necessary to validate this solution.
Distribution
- Indian Ocean; Recent
- Western Pacific; Recent
Paramontastraea has a disjointed distribution among species—P. salebrosa in the Central Indo-Pacific, and P. peresi and P. serageldini in the Indian Ocean region.This page has been in preparation since 06-Feb-2014 14:24
This version was contributed by Danwei Huang on 06-Feb-2014 18:54.
Page authors are: Danwei Huang. Please contact the editor if you would like to contribute to the diagnosis of this taxon.
The editor is: Ann Budd
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