Triphyllozoon indivisum Harmer, 1934

(Figs 2F, 7 A–C; Table 6)

Triphyllozoon indivisum Harmer, 1934: p. 614, text-figs 25F, 40, pl. 35, figs 33, 34, pl. 40, figs 10–12. Hayward, 2000: p. 112, fig. 2d–e.

Material examined. KJBR 46, Stn KJ01-1; KJBR 47, KJBR 48, Stn KJ01-2; KJBR 49, Stn KJ01-3.

Description. Fragments flat, fan-shaped. Fenestrulae broadly oval (Fig. 7A), trabeculae mostly narrower, consisting of 3–4 longitudinal autozooidal series. Autozooids convex, oval to hexagonal at growing edge, separated by raised sutures. Frontal shield slightly nodular, with 4–6 marginal pores, these sometimes very large. Lateral condyles obscured by secondary calcification; rounded pseudospiramen (labial pore) medially placed below the orifice. Secondary calcification largely concealing the primary orifice. Avicularia of two types: the most characteristic is large, asymmetrical, proximal within fenestrula margins, the rostrum narrowed medially, larger distally and ending in two upcurved asymmetrical tips (Fig. 7B, arrow); the other avicularium is smaller, placed on the frontal shield and near zooid margins, varying from oval to subcircular in shape. Each autozooid bearing one or more frontal avicularia. Ovicell longer than wide, with a single median longitudinal suture that is unbranched (Fig. 7C), with no lateral sutures, apertural rim straight-edged.

Remarks. This species has two kinds of avicularia, distinguished by size—large asymmetrical avicularia flanking the fenestrulae, and small elongate-oval avicularia on the frontal surface. The ovicell of this species is also distinguished from other species of Triphyllozoon in having an unbranched median longitudinal suture (Hayward 2000; Tilbrook 2006).

Distribution. Triphyllozoon indivisum was originally described from Sulawesi, Indonesia, and the Solomon Island where it is common at Anuha Reefs, Florida Islands, Mbanika Island and Russell Islands (Tilbrook 2006).