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Synonyms: Corunastylis sp. aff. sagittifera 1 (sensu Bower & Medd 2023) APNI*

Description: Terrestrial tuberous herb.

Leaf c.16 cm long, 2.0 mm wide, terete, green with reddish base, lamina sheathing the scape, free lamina 16 mm long and 2.0–3.0 mm wide, ending at the level of the first flower.

Inflorescence 32 mm long above leaf, bearing 6–10 flowers in a densely crowded spike 12–18 mm long; flowers opening in sequence from the base; pedicel 1 mm long, ovary 4mm long on fully opened flowers, weakly curved, dorsal margin in profile falcate, ventral margin in profile straight, flower attachment line flush with ventral ovary margin; ovary ridged, ridges sometimes suffused with purple in the outer half, smooth between ridges. Flowers porrect, yellow-green with magenta markings on dorsal and petals, and yellow-white and purple-black markings on the labellum, 5.45–6.87 mm wide. Dorsal sepal yellow-green with 5 purple stripes, 3 along medial veins and one on each margin, 6.10–6.58 mm long, c. 2.0 mm wide in situ, lanceolate-ovate, tapering from broad base to an attenuate apex, in profile the margin straight, the sepal body deeply concave, margins entire. Lateral sepals green in flower bud, becoming paler with flower opening and age to yellow-green in some individuals 5.74–7.24 mm long, 1.18–1.37 mm wide, lanceolate-falcate, widest just above base but scarcely tapering except for inrolled margins from around mid-point, concave toward apex, apex with a short non-glandular apiculus. Petals 3.89–4.32 mm long, 1.08–1.33 mm wide, lanceolate and weakly falcate, pale yellow-green, paler at base, with margins magenta-pigmented at least in the upper two thirds, pigmentation sometimes absent in the basal third, with three incomplete magenta lines on the petal lamina, of variable length and start and end point, with the medial the strongest of the three and extending the furthest toward and usually into the petal apex; mid-vein thickening toward apex and forming a prominent costa that extends beyond the petal apex and a short acuminus; margins sparsely and shortly denticulate to ciliate. Labellum three toned, deep purple at the apex and on margins, bright yellow at the base, and nearly hyaline either side of the callus at middle, 3.32–4.46 mm long, including apex when flattened, 1.90–2.03 mm wide, broadly elliptic to very weakly obovate, widest at or just above the midpoint, with sides tapering therefrom toward the base nearly straight, and toward the apex evenly curved, apex with a short apiculus, often recurved in a line following that of the downward-swept labellum margins; in profile the labellum is falcate in its outer half, and slightly bulbous in its lower half; margins with numerous dark purple cilia, from one quarter the margin length above the base to the apex, toward the base cilia are shorter, and increase in length with increasing distance above the base and around the labellum apex cilia are turgid, non-flexuous, and up to 1 mm long; labellum margin entire at base; callus forms two distinct bulbs at the labellum base that are raised above and below the labellum lamina, these bulbs are bright yellow-green, with papillose surface, and no, or very sparse, purple pigmentation, that present only medially; between the two bulbs is a shallow depression that deepens and widens toward the labellum base; cells on the adaxial surface of the bulbs are arranged in longitudinal rows, the bulbs themselves are ovoid, and weakly attenuated antically, toward their junction, above which the callus continues as a pronounced half-cylinder raised above the labellum lamina, red-brown pigmented at the base, deepening to dark purple at the apex, sometimes nearly black, in the upper quarter the callus tapers toward the labellum apex, where it extends into the short narrow-triangular apiculus which is comprised either entirely of callus, or primarily of callus with a narrow flanking wing of lamina tissue on either side; cells on the half-cylindrical callus are papillose and arranged in longitudinal rows at the base, and lengthen and become smooth toward the apex, at which point they are long-rectangular and longitudinally orientated in callus middle, and laterally divergent toward the respective margin on either side of the mid-section; lateral-medial labellum lamina above the basal callus-bulbs is nearly unpigmented and hyaline, in this region the smooth cells glisten and sparkle in their reflectance of all incident light. Column 3 mm long not including column foot, 1.6 mm wide; column foot present, wings unequally bilobed, upper lobe hyaline, triangular with a obtuse apex to oblong with an asymmetrical apex, margins entire, smaller and narrower than lower lobe; lower lobe succulent, hyaline with faint magenta suffusion along outer half below apex, triangular, apex acute, margins ciliolate toward apex, becoming shorter with distance from apex, ciliola apex slightly bulbous, tall dome-shaped papillae mixed in among cilia, and both present on the outer surface of the lobe as well as its margin, inner surface with papillae; anther versatile, 0.7 mm long, broad elliptic, with a filiform rostrum. Pollinarium bright yellow.

Habit Photo A.E. Orme

Flower Photo A.E. Orme

Other photo Photo A.E. Orme

Flowering: Late January to late March

Distribution and occurrence: Known to occur between the Marulan and Wambool districts.

Growing in dry sclerophyll forests. At Brayton, recorded with Eucalyptus cinerea, E. macrorhyncha and E. bridgesiana, with mid-dense grass and forb ground layer The geology is recorded as Devonian granites.
NSW subdivisions: CT

AVH map***

The labellum of Genoplesium sp. Brayton (K.Mauger s.n., NSW1255150) bears conspicuous cilia on its margin, while the dorsal sepal and petal margins are entire. In this combination of characters the plant is a member of section Pachychila (Group 2 in Jones 2024). Among the species of Group 2 G. sp. Brayton (K.Mauger s.n., NSW1255150) possesses a relatively uncommon feature, which is that the labellum callus extends to the labellum apex, either as a continuation of the raised region or as an extension of elongated cells comprising the apical portion of the callus, but which is not conspicuously raised above the surrounding labellar cells. The apiculus at the labellum apex is comprised either primarily, or entirely, of callus. Four other species of sect. Pachychilum share with G. sp. Brayton (K.Mauger s.n., NSW1255150) a callus that extends into the labellum apex: Genoplesium ciliatum, G. morinum, G. rhyoliticum and G. stephensonii. The flowers of Genoplesium sp. Brayton (K.Mauger s.n., NSW1255150) have a distinctive appearance in profile, because they appear to have a relatively small labellum in proportion to the overall size of the flower. This appearance is imparted by the relatively long dorsal sepal and slightly shorter petals, relative to the lateral sepals, in comparison with other species of sect. Pachychila. The dorsal sepal, at 6.1-6.6 mm long (slightly longer in older flowers) is among the longest within the section, and serves to separate G. sp. Brayton (K.Mauger s.n., NSW1255150) from G. ciliatum, whose dorsal sepal is 4 mm long. The lateral sepals of G. sp. Brayton (K.Mauger s.n., NSW1255150) are also longer than in G. ciliatum, at (5.74-)6.21–7.24 mm compared with 5 mm, though their width is comparable, as are the petal and labellum dimensions. The labellum callus of G. ciliatum does not have the paired prominent bulbs at the labellum base that there extend to the labellum margin, as occurs in G. sp. Brayton (K.Mauger s.n., NSW1255150), and its close relatives including G. cornutum and G. sagittiferum. The dorsal sepal length of G. sp. Brayton (K.Mauger s.n., NSW1255150) is similar to that of G. morinum, whose dorsal sepal is around 6 mm long, however the petals of G. sp. Brayton (K.Mauger s.n., NSW1255150) are shorter, at 3.89-4.32 mm compared with c. 5.5 mm long in G. morinum. The lateral sepals of the two species are more or less the same length, but those of G. sp. Brayton (K.Mauger s.n., NSW1255150), at 1.18-1.31 mm wide, are narrower than the lateral sepals of G. morinum, which are 1.5-1.8 mm wide. The shape of the labellum callus also differs between these two species, with G. sp. Brayton (K.Mauger s.n., NSW1255150) having the callus parallel-sided in its antical half, and flaring widely on both sides in its basal half into the paired basal bulbs. In contrast, the callus of G. morinum tapers more or less evenly and continuously from base to apex. The shape of the labellum callus also serves to differentiate G. sp. Brayton (K.Mauger s.n., NSW1255150) from G. rhyoliticum, because the callus of G. rhyoliticum tapers evenly from base to apex, and does not flare toward the base into paired bulbs. The dorsal sepal of G. sp. Brayton (K.Mauger s.n., NSW1255150), at 6.1-6.6 mm, is longer than that of G. rhyoliticum, whose dorsal sepal is around 4.5 mm long. The lateral sepals of G. sp. Brayton (K.Mauger s.n., NSW1255150), at 5.7-7.2 mm long and 1.2-1.4 mm wide, are longer and slightly wider than those of G. rhyoliticum, are around 5 mm long and 1 mm wide. The dorsal sepal of G. sp. Brayton (K.Mauger s.n., NSW1255150) (6.1-6.6 mm) is also longer that that found in G. stephensonii, in which the dorsal sepal is 4.5-5.0 mm long. The lateral sepals are longer in G. sp. Brayton (K.Mauger s.n., NSW1255150) (5.7-7.2 mm), than those in G. stephensonii (5.0-5.5 mm). The lobes on the column wing also differentiate G. sp. Brayton (K.Mauger s.n., NSW1255150) from G. stephensonii.