Mezoneuron scortechinii F.Muell.
Mueller, F.J.H. von (1882) Southern Science Record 2: 73. Type: "Known from the forest-regions between the Logan-River (Scortechini), Wide-Bay (Bidwill), and the Burnett-River (F.v.M.)."
Vine stem diameters to 7 cm recorded. Blaze very fibrous.
Leaves bipinnate, each leaf with 150-200 leaflets. Leaflet blades about 6-18 x 4-10 mm, leaflet stalks less than 1 mm long. Lateral veins difficult to distinguish. Stipules small and inconspicuous, about 1-1.5 mm long. Recurved spines present on the underside of the compound leaf rhachis and on the twigs. Primary and secondary compound leaf axes clothed in brown or reddish brown hairs.
Inflorescence about 14-24 cm long. Flowers about 4-5 mm diam. at anthesis. Calyx tube (hypanthium) about 1-2 mm long. Sepals unequal in size, one larger than the rest, each sepal about 3-7 mm long. Petals unequal in size, about 3-5 mm long, each with a tuft of hairs on the inner (adaxial) surface near the base. Stamens 10, dimorphic. Anthers about 1 mm long, clothed in hairs, filaments 3-6 mm long, densely clothed in hairs, particularly towards the base. Ovary about 4 mm long. Style about 6 mm long. Stigma excavated, with hairs on the margin of the structure. Ovules 1.
First leaf bipinnate with four secondary axes each with six or seven leaflets. Second leaf bipinnate with four secondary axes each with eight leaflets. Leaflets mainly glabrous, small, about 4-6 mm long, obovate, apex retuse, base oblique and obtuse. Stem (above the first leaf) compound leaf petioles and the compound leaf primary axes armed with short spines. Stems, compound leaf petioles and compound leaf primary and secondary axes clothed in short golden brown hairs. At the tenth leaf stage: stem and compound leaf primary axes armed with sharp spines, compound leaves bipinnate, each leaf with 18-28 secondary axes each with about 12-16 leaflets. Leaflets oblong-elliptic to obovate, apex emarginate, base oblique and obtuse. Stipules 1.5 mm long, caducous. Seed germination time 74 days.
Caesalpinia traceyi Pedley, Austrobaileya 5: 99(1997). Type: Kuranda, Cook District, Qld, 7 Nov. 1958, L. S. Smith 10448; holo: BRI; iso: K. Mezoneuron traceyi R.P.Clark, Phytotaxa 274(1): 30-32 (2016).