Description. Solitary (Fig. 2 a – b, 2 d): 3.6 – 8.4 mm long, excluding posterior projections. Body elongated cylindrical. All test echinate, especially projections, strongly papillated all over the test. Test cylindrical, thickened ventrally around nucleus, with two long posterior projections. Oral opening terminal, atrial opening postero-dorsal. Atrial palps bifurcate. Medioventral projections well developed and lower one longer than upper one. Lateral projections well developed, fairly long. Body muscles thick. Five body muscles, MI to MIV continuous dorsally and ventrally, MV interrupted ventrally. MI to MIII and MIV to MV contiguous or fused in mid-dorsal line. Intermediate muscle interrupted dorsally and converge to MI. the number of muscle fibres varies from 77 – 106. Dorsal tubercle simple and small, separated from ganglion with short distance. Branchial septum slender, extending from ganglion to gut. Endostyle thin, extending from behind oral to posterior ventrally. Gut forming a compact nucleus, stolon coiled around it. Aggregate (Fig. 2 c, 2 d): 0.8 mm long. Body pentagonally shaped anteriorly with relatively hard, sharp-edged test. Test echinated. Sharply pointed posterior. The attachment organs vary in number and never protruding beyond test wall left posterior. Body muscles MI – MIII and MIV – MV fused over a short section. Muscle bands are wide, number of muscle fibres is usually 16. Gut forming a compact oval nucleus. Nucleus projection absent. The endostyle is short, only nearing to the MII. Ovary and embryo are situated on MIV, close to the nucleus. The gill are slender.
Sumber: A taxonomic revision of the genus Thalia Blumenbach, 1798; Weelia Yount, 1954; Brooksia Metcalf, 1918 (Salpida: Salpidae) from East Coast of Peninsular Malaysia