Quinqueloculina

Quinqueloculina sp. 3 (Fig. 11:1, 2)

Description. Test elongate with Quinqueloculina - type coiling, approximately twice as long as wide; oval crosssection. Slightly inflated chambers with distinct, straight, depressed sutures. Rough test wall with patchy, discontinuous, usually weak to moderately defined longitudinal costae extending length of test. Distinct sutures depressed, straight. Aboral end rounded, slightly produced. Aperture terminal, slightly produced, circular with thin peristomal lip; short, bifid, T-shaped tooth.

Remarks. This species has a combination of common morphological features that are often observed as part of the intraspecific variation displayed by other Quinqueloculina species. This species is distinguished from other Quinqueloculina by its elongated test, sporadic longitundal costae, straight sutures and circular aperture with a slight lip and bifid dentition (Fig. 11:1, 2). However, many other species share similarities with Quinqueloculina sp. 3, but there are always fundamental differences. The greatest similarity to Quinqueloculina sp. 3 is shown by Quinqueloculina sp. 2. The general descriptions are extremely similar, but the aboral end of Quinqueloculina sp. 2 is more pronounced, the chambers are more inflated, the test is stouter, the costae are more irregular and the aperture, whilst similar in shape and dentition, is much larger in proportion to the rest of the test. These similarities may indicate conspecificity, but the low abundance of both taxa makes it difficult to be confident and so both taxa have been left in open nomenclature until additional material is available.

Distribution within study area. Quinqueloculina sp. 3 was mainly collected from lagoons of the CG. Abundance was normally low in transect samples and this species was absent from Sykes Reef. Greatest abundance was found at site 42 on Heron Reef flat and sites 25 and 52 in One Tree Lagoon 1 and 2, respectively.