Astreopora acroporina, Wallace & Turak & DeVantier, 2011

Wallace, Carden C., Turak, Emre & DeVantier, Lyndon, 2011, Novel characters in a conservative coral genus: three new species of Astreopora (Scleractinia: Acroporidae) from West Papua, Journal of Natural History 45 (31 - 32), pp. 1905-1924 : 1914-1915

Astreopora acroporina sp. nov.

( Figures 2B , 4 )

Type locality

Cenderawasih Bay , West Papua .

Material examined

Holotype. MTQ: G60692 Indonesia, West Papua, Cenderawasih Bay, Pulau Nurage TNTC 3 ◦ 1.8 ′ S, 134 ◦ 50.1 ′ E; depth 3 m collected L. DeVantier 19 February 2006.

Paratypes. MTQ: G60691, G60693 Indonesia, West Papua, Cenderawasih Bay, Tanjung Womosisore TNTC 3 ◦ 5.9 ′ S, 134 ◦ 50.3 ′ E, depth 1 m, collected E. Turak 18 February 2006 ; G60694 Indonesia, West Papua, Cenderawasih Bay, South Yapen, Marai , 1 ◦ 43.9 ′ S, 135 ◦ 46.3 ′ E, depth 1 m, collected E. Turak 14 February 2006 .

Etymology

Named for its central or axial corallite, as in Acropora .

Diagnosis

Colony consisting of irregular vertical branching units with an axial corallite and a greater or lesser degree of secondary branching, the secondary branches also having an axial corallite. Basal areas of one smaller colony have some solitary corallites on a roughly hemispherical structure, from which only a few branches are given off. Axial corallites extend throughout the extent of branches. Radial corallites have a similar appearance to axial corallites, without the extended axis, i.e. they are tubular with round openings. These occur scattered and not touching on both branches and branchlets, the longer radials only distinguished from axials by the absence of radial corallites. Coenosteum of evenly distributed spinules, which are low conical with irregular blade-like tops.

Skeletal characteristics

Holotype. Part of colony, 125 mm greatest width and 100 mm height, with 10 supplementary fragments 14–53 mm long and nine smaller fragments. Corallum consists of numerous branches, irregular in shape and length, given off from an irregular base. Branches up to 70 mm long, 11–15 mm basal width but in some cases wider further up the branch. Branchlets and incipient branchlets are given off in an irregular arrangement along the extent of the branch. Each branch or branchlet has an axial corallite running from base to tip. Axial corallite diameters: outer 2.58–4.45 mm, inner 1.5– 2.51 mm; six primary septa present, as complete or incomplete vertical plates, flaky in appearance, sometimes broken into segments, all or some twisting to form a trabecular pseudo-columella towards the base of the corallite; secondary septa all present, up to 1 / 4R. “Radial” corallites occur scattered and not touching on both branches and branchlets; the longer radials only distinguished from axials by the absence of radial corallites. Corallite shape conical to tubular with round opening; outer diameter 1.47–1.56 mm, inner diameter 1.06–1.25 mm; radial septa vertical laminae or broken laminae, some to all meeting deep within the corallite; secondary septa present up to 1 / 4R as laminae to broken laminae. Coenosteum the same on and between corallites: evenly distributed spinules which are low conical with an irregular blade-like top.

Variations shown in paratypes. Two of the paratypes (G60691 and G60694) have about half of the corallum with very little branching, the corallites being of varying heights and some appearing to be incipient axial corallites, while the other half of the corallum is fully branching.

Field characteristics

Colour pale brown-grey, colonies mostly no more than 200 mm in diameter.

Habitat

Sandy reef flat and upper reef slope at 1–2 m.

Distribution

To date, recorded from Cenderawasih Bay only; see Figure 1 .

Figures

Figure 1. Map of Cenderawasih Bay, West Papua, showing locations for new Astreopora species. Symbols: triangles, Astreopora cenderawasih; squares, Astreopora acroporina; circles, Astreopora montiporina; (see Turak and DeVantier, forthcoming, for locations of all sample sites).

Figure 2. Field appearance of the three new Astreopora species in Cenderawasih Bay, West Papua. (A) Astreopora cenderawasih; (B) Astreopora acroporina; (C) Astreopora montiporina.

Figure 4. Astreopora acroporina sp. nov. Holotype (A–C) MTQ G60692; (D, E) MTQ G60691; (A) Whole corallum; (B) branch tip showing axial and radial corallites; (C) group of branches; (D) scanning electron micrograph (SEM) showing coenosteal spinules; (E) SEM showing axial corallite. Scale bars: A, C: 10 mm; B, D: 1 mm; E: 500 µm.