Paraclavarina, VERON, 1985: 179

Huang, Danwei, Benzoni, Francesca, Fukami, Hironobu, Knowlton, Nancy, Smith, Nathan D. & Budd, Ann F., 2014, Taxonomic classification of the reef coral families Merulinidae, Montastraeidae, and Diploastraeidae (Cnidaria: Anthozoa: Scleractinia), Zoological Journal of the Linnean Society 171 (2), pp. 277-355 : 330-332

publication ID

https://doi.org/ 10.1111/zoj.12140

persistent identifier

https://treatment.plazi.org/id/6A35B423-184F-FFC7-861B-880CFD2DFEB1

treatment provided by

Marcus

scientific name

Paraclavarina
status

 

GENUS PARACLAVARINA VERON, 1985: 179 View in CoL ( FIG. 20 View Figure 20 )

Type species

Clavarina triangularis Veron & Pichon, 1980: 223 View in CoL , figs 375–384; original designation, Veron, 1985: 179.

Original description

Paraclavarina is like Merulina except that it is ramose without any development of laminae. It is the only fully ramose genus in the Merulinidae .

The description of Clavarina triangularis by Veron & Pichon (1980) is repeated below.

“Colonies, which frequently exceed 1 m diameter, resemble those of Hydnophora rigida in consisting entirely of a network of anastomosing branches without any plate-like or foliaceous basal attachment. Some colonies have lax, open branching, while others are compact and bushy. Old branches may be up to 1.5 cm thick; most average 1 cm except towards the tips where they taper. All branches are basically triangular in section and have three series of centres, one on each side, with the angles being the common walls. On most branches the series of centres are straight and divide only when the branch divides. Thicker branches may have more irregular series with frequent divisions not associated with sub-branches and branch sections may be more circular than triangular. Branch tips are threepointed star-shaped in section, with the centres lying along the valleys and the walls forming the points. Septa are in two alternating orders. First order septa are slightly exsert, either adjoined over the wall or, more usually, separated by a groove. They increase in thickness towards the “valley” axes and most curve towards the nearest centre. Their inner margins, which are mostly vertical, may have large dentations. However, most skeletal structures at the centres and along the valley axes are fused together so that the centres are star-shaped, consisting of 5–10 thick, radiating septa with fused inner margins and deep inter-septal loculi. Second order septa are short and usually thinner than those of the first order. All septa are dentate, those of the first order usually more so than those of the second. Centres are linked by a single, sometimes very thick, laminar plate, which itself is fused to adjacent septa. There are no clearly defined calices and valleys are often very superficial. Columellae may be trabecular or spongy, but are only distinguishable as such near branch tips. Individual centres and the perimeter of oral discs are clearly defined in living coralla. When polyps are expanded at night, fine, elongate tentacles usually occupy most of the space between the branches. Colonies are pale yellow or cream.” ( Veron & Pichon, 1980: 225)’ ( Veron, 1985: 179–180).

Subsequent descriptions

Veron, 1986: 438; Veron, 2000, vol. 2: 374.

Diagnosis

Colonial, with intracalicular budding only. Corallites monomorphic, uniserial, and ramose; monticules absent. Walls fused. Calice width small (<4 mm), with low relief (<3 mm). Costosepta confluent. Septa in <three cycles (<24 septa). Free septa present but irregular. Septa spaced six to 11 septa per 5 mm. Costosepta equal in relative thickness. Columellae trabecular but compact (one to three threads), <1/4 of calice width, and continuous amongst adjacent corallites. Paliform (uni- axial) lobes well developed. Epitheca absent and endotheca sparse ( Fig. 20 View Figure 20 ).

Species included

Paraclavarina triangularis ( Veron & Pichon, 1980: 223, figs 375–384); holotype: NHMUK 1983.9 About NHMUK .27.2 (dry specimen; Fig. 20 View Figure 20 ); type locality: Bushy Island−Redbill Reef , Australia, 5 m depth; phylogenetic data: none .

Taxonomic remarks

Paraclavarina Veron, 1985: 179 View in CoL , was established as a monotypic genus with close affinity to Merulina View in CoL . Its sole member was initially described as Clavarina triangularis Veron & Pichon, 1980: 223 View in CoL , for its similarity to Merulina scabricula View in CoL , effectively resurrecting Clavarina Verrill, 1864: 56 View in CoL , for these two species ( Merulina scabricula View in CoL being the type), where Chevalier, 1975: 208, had previously synonymized it. Studying specimens from Phuket and the Mergui Archipelago, Veron (1985: 181) deemed Clavarina triangularis Veron & Pichon View in CoL to be distinct from Merulina ampliata View in CoL and Merulina scabricula View in CoL , which were more similar to each other instead. No details on these new observations were offered. Clavarina View in CoL effectively became synonymized as Merulina View in CoL once again, and Clavarina triangularis View in CoL was transferred into Paraclavarina View in CoL .

It should be noted that two of the three syntypes of Merulina scabricula View in CoL (USNM 165 and YPM IZ 1927A; see species included for Merulina View in CoL ) are ramose like Clavarina triangularis View in CoL . Umbgrove (1940: 285) argued that Dana (1846: 275) based his description of this species only on part of a large colony that may have thin lamina at its base like Merulina ampliata View in CoL . Evidently, neither he nor Veron (1985: 181), who referred to USNM 165 incorrectly as the holotype, saw the final syntype (YPM IZ 1927B), indeed a fragment of lamina. If this is indeed the pattern observed by Veron (1985: 181), then distinguishing the fully ramose Clavarina triangularis View in CoL from Merulina View in CoL , and by extension the establishment of Paraclavarina View in CoL may be justified.

Evidently, the validity of Paraclavarina depends critically on its specific relationships with Merulina ampliata and Merulina scabricula . To date, Paraclavarina triangularis has never been collected for a phylogenetic study, and only three samples of each Merulina species have been analysed ( Romano & Palumbi, 1996; Chen et al., 2002; Fukami et al., 2008; Huang et al., 2011).

Paraclavarina is known only from the Central Indo- Pacific region bounded by the Makassar Strait, Palau, Papua New Guinea, Vanuatu, and the Great Barrier Reef in Australia.

Morphological remarks

The holotype of Paraclavarina triangularis has been examined and found to share all analysed macromorphological features with Merulina . It is however fully branching, lacking the encrusting and/ or laminar base found in Merulina .

GENUS PARAMONTASTRAEA HUANG & BUDD

Kingdom

Animalia

Phylum

Cnidaria

Class

Anthozoa

Order

Scleractinia

Family

Merulinidae

Loc

Paraclavarina

Huang, Danwei, Benzoni, Francesca, Fukami, Hironobu, Knowlton, Nancy, Smith, Nathan D. & Budd, Ann F. 2014
2014
Loc

PARACLAVARINA VERON, 1985: 179

Veron JEN 1985: 179
1985
Loc

Paraclavarina

Veron JEN 1985: 179
Veron JEN 1985: 181
Veron JEN & Pichon M 1980: 223
Chevalier JP 1975: 208
Verrill AE 1864: 56
1985
Loc

Clavarina triangularis

Veron JEN 1985: 179
Veron JEN & Pichon M 1980: 223
1980
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