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Nuylsia Vol. 7,No.2(1990) 
Nearly all Australian species of Trianthema are annual herbs; only T. turgidifolia F. Muell. is 
more or less shrubby and perennial. A number of species are conspicuously hairy on all green parts 
(e.g. T. pilosa F. Muell., T. rhynchocalyptra F. Muell.); others are only sparsely pubescent or 
completely glabrous (e.g. T. porlulacasirum L., T. triquetra). The new species belongs to the latter 
group and is closely related to T. compacta C. While, T. glossostigma F. Muell., and T. oxycalyptra 
F. Muell. 
Trianthema kimberleyi Bittrich & Jenssen sp. nov. (Figure 1) 
Flerba annua, glabra, prostata, c. 5 cm alta et 20 cm diametro; folia opposita, carnosa, 
inaequalia, basaliter connata, saepe apiculata, lamina late obovata vcl ovalis, c. 4-1 1 mm longa et 
1.5-5 mm lata; petiolus c. 1-2 mm longus, basaliter cum vaginis membranaceis bidentatis; flores 
solitarii, breviter pedunculati; bracteae 2, membranaceae, apiculatae et denticulatac; tepala 5, basi 
connata, valvata, dorso viridia, intus albidarosea; stamina 10, 5 opposititcpala, 5 altcmitcpala; stylus 
1, c. 1.2 mm longus; ovarium simplex uniloculare, placentatione marginali, ovulis biscriatis; ovula 
10-12; capsulae circumscissae, cum pedicellis, operculis conicis; semina c. 1.1 mm longa, 
brunneanigra, glabra, cum arillis omnino vaginata; embryo hippocrepicus; chromosomatum 
numerus 2n = 48. 
Typus : c. 20 km south of the Great Northern Highway between Fitzroy Crossing and Halls Creek, 
199 km west of Halls Creek, c. 2 km WSW of Christmas Creek homestead, Western Australia; near 
a small lake on flat hills in schistose rocks, 15 March 1989, V. Bittrich & K. Jenssen 18618 (holo: 
HBG; iso: CANB, K, PERTH). 
Much branched, prostrate, annual herb c. 20 cm in diameter and 5 cm high, glabrous. 
Branching in the vegetative part of the plant monopodial, in the flowering region sympodial, the 
branches here of unequal diameter. Leaves opposite, flat, elliptical to obovate, 4-1 1 mm long and 
1.5-5 mm broad, often with a short mucro at the apex, basally shortly connate, weakly papillose, 
succulent due to the large water-storing cells of the epidermis and hypodermis, reddish on the 
abaxial surface; leaves in the flowering region anisophyllous, with the thicker sidcbranch in the axil 
of the larger leaf; petiole 1-2 mm long, basally expanded into a membranaceous sheath with two 
acuminate lobes. Flowers solitary, axillary, with an intense honey smell at anthesis; pedicels up to 
2 mm long at anthesis, but elongated to up to 5 mm when fruiting, with two scarious, lanceolate, 
apiculate and denticulate bracts; perianth c. 7.5 mm in diameter, 5-partite; tube obconical, c. 2 mm 
long, with a whitish nectary disk inside at the base; lobes green outside, whitish-pink inside, 
valvate; stamens 10, 5 opposite and 5 alternate to the tcpals, inserted at the mouth of the perianth 
tube; anthers pale pink, smooth; style 1, filiform with a row of short papillae on one side; placenta 
marginal with 10-12 ovules in 2 rows. Capsule dehiscing by circumscissile split about the middle, 
operculum subovoid; seeds 6-8, broadly ovoid or pyriform, c. 1.1 x 0.9 x 0.6 mm, brownish to 
black, smooth, completely sheathed by an aril, which sw'clls slightly when moistened; embryo 
horseshoe-shaped, curved around the mealy perisperm. Chromosome number 2n = 48. 
Distribution. Known only from the type locality in the southern Kimberley region where it is 
confined to the Hall District of the Northern Botanical Province of Western Australia. 
Habitat. Grows on Oat hills in schistose rocks. 
Flowering and fruiting period. March to ?. 
Conservation status. Rare. 
