Quinqueloculina baccaerti Mamo, 2016, n. sp.

Quinqueloculina baccaerti n. sp. (Fig. 8:3, 4)

1987 Quinqueloculina montyi Baccaert 1987, p. 104, pl. 48.

2001 Quinqueloculina bicarinata d’Orbigny; Lobegeier, p. 291, pl. 7, figs 10–16 2009 Quinqueloculina sp. 1, Parker, p. 288, figs 208a–m, 209a–i.

Diagnosis. This species is defined by its combination of a broad, uncompressed test with inflated chambers and rounded peripheries, their roughened test wall texture and weak, longitundinal striate ornament.

Description (after Baccaert 1987; Parker 2009): Test slightly longer than wide, with quinqueloculine chamber arrangement. Test wall porcelaneous with a roughened texture. Rounded aboral end produced. Oral end slightly produced and rounded. Faint longitundal striae give slightly carinate appearance to rounded margins. Distinct sutures depressed. Aperture flush against oral end of final chamber, low arch to circular in outline with a moderately thick, everted lip. Dentition consists of a stout, low, bifurcate tooth.

Remarks. This species was originally reported in an unpublished thesis by Baccaert (1987) from Lizard Island, GBR as Quinqueloculina montyi Baccaert 1987. Whilst the name Q. montyi is used in publication (Baccaert 1986), it is only listed, no holotype is designated and no description or illustration is supplied. Therefore, the name is not available. The taxon is similar to specimens described by Parker (2009) from Ningaloo Reef as Quinqueloculina sp. 1.

This species is characterised by a roughened test wall texture, weak striate ornament, inflated chambers with rounded peripheries and an arched to circular aperture with a bifurcate tooth (Fig. 8:3, 4). These features suggest a close association with Q. latidentella, Q. subgranulata and Quinqueloculina sp. 2. Quinqueloculina baccaerti differs from Q. latidentella by its broader, uncompressed test and coarser test walls with a striate ornament. Quinqueloculina latidentella has a peristomal rim and a stouter and thicker tooth than Q. baccaerti. Quinqueloculina subgranulata has more inflated chambers with a rougher test wall texture, lacks striae and has a thicker peristomal lip and tooth compared to Q. baccaerti. Quinqueloculina sp. 2 has a similarly rough test wall and striate ornament as Q. baccaerti, but differs by its stouter test with a proportionately larger aperture and Tshaped bifid dentition.

Baccaert’s (1987) specimens were collected from Lizard Island, GBR and Parker (2009) synonymised these with Lobegeier’s (2001) Quinqueloculina bicarinata from Green Island. The specimens described by Parker (2009) from Ningaloo Reef, Western Australia bear subtle differences in morphology. The CG specimens lack the carinate peripheries that some of Parker’s (2009, figs 208a–c; j–l, 209a–c, 210h–j) specimens have that give such tests an inflated, ‘knife-edge’ appearance. The CG specimens always possess a weakly expressed ornament of longitudinal striate. However, striae are absent in some of the morphologies illustrated by Parker (2009) that leave the porcelaneous walls relatively smooth, as is the roughened texture that is a distinct attribute of this species.

Derivation of name. Named after Jan Baccaert, the original founder of this species.

Material. Holotype—QM#G465818 (Fig. 8:3, 4); Paratypes—QM#G466092, QM#G466093, from 7 m water depth at sites 36 (Holotype) and 39 (Paratypes), One Tree Lagoon 1, Capricorn Group, Great Barrier Reef, Queensland, Australia, Holocene.

Distribution within study area. Quinqueloculina baccaerti is the fourth most abundant quinqueloculine species collected from the CG where it is a distinct component of lagoonal assemblages with as many as fifty-eight specimens found per site. The site of highest abundance is site 34 in One Tree Lagoon 1. This taxon was entirely absent from Sykes Reef and only one specimen was collected on Heron Reef flat and two specimens from the channel sample.