User:Dwergenpaartje/Otholobium piliferum

Otholobium piliferum is a small creeping subshrub that occurs only above ground ater a fire has destroyed the vegetation. Flowering has been recorded in Septem- ber and January.

Taxonomy

This species was first collected for science by Sim in 1892 and Bulcock in 1914, and after more than 70 years again near Stutterheim, about 70 km north-east of Oos-Londen. Charles Stirton and A. Muthama Muasya considered it sufficiently different from its relatives, described it in 2017, and called it Otholobium piliferum. The name of the genus Otholobium is a combination of the Greek words ὠθέω (ōthéō) meaning to push and λοβός (lobos) meaning pod, which Stirton selected because its fruit seems to be pushed out of the calyx. The specific epithet (piliferum) is a Latin word meaning "carrying pills", referring to the .

Description

Small, decumbent pyrophyte. Stems many, up to 30 cm long, appressed pubescent, slender, striate. Leaves digitately trifoliolate, petiolate, erect. Leaflets unequal; terminal leaflet 10–13 × 3–4 (–5) mm, obovate; laterals smaller, asymmetrical, upper margin straight, lower convex; veins distinct below, apex acute, base cuneate, glabrescent; glands impressed, more evident on upper surface; petioles 2–4 mm long, petiolules 0.75–1 mm long. Stipules 4–5 mm long, narrowly subulate becoming broadly subulate in upper axils, ciliate. Inflorescences pedunculate, axillary, common in upper 2/3 of seasonal shoots, each comprised of a triplet of pedicellate flowers, each triplet subtended by a yellowish 3 mm long, oblong-obovate, irregularly toothed, truncate bract; peduncle 4 mm long. Flowers 8–9 mm long, pedicels 3 mm long, white suffused with mauve; each flower subtended by a 3 mm long, cucullate, narrowly lanceolate bract. Calyx longer than the corolla; 8–10 mm long; carinal lobe longest, 6.5–7 × 2.5–3 mm, acuminate, three times longer than the 3 mm long tube; vexillary teeth shortest, not fused above the tube, lateral teeth intermediate, ribs weak, finely glandular mostly on the tube, margin of the teeth velutinous. Standard 9–10 mm, claw 2 mm long, elliptic, apex obtuse, auriculate. Wing petals 8–9 × 2 mm, claw 2–3 mm wide; auriculate; sculpturing present, upper basal and upper left central, comprised of up to 10 transcostal lamellae. Keel petals 6 × 1.5 mm, claw 3 mm long, base curling upwards. Androecium 6–6.5 mm long, vexillary stamen free. Pistil 5–5.5 mm long; ovary 1.25–1.5 mm long, sparsely stalked-glandular, gynophore 0.4 mm long; style glabrous, entasis developed maximally at point of flexure, height of curvature 1.5 mm, stigma penicillate. Fruits and seeds unknown.

Differences with related species

Otholobium piliferum is easily separated from all other species of Otholobium by a combination of its decumbent habit, long hair-like mucro on the leaflets, and narrowly subulate stipules.

Conservation, distribution and ecology

Otholobium piliferum is one of the rarest species in the genus. We assess the IUCN Conservation status of this species as Data Deficient (DD). As this taxon is only known from two collections and its habitats are likely to have experienced transformation in recent years, it is most probably threatened with extinction. The Rabinowitz Rarity Code is RSN (restricted, sparse, narrow); constantly sparse and geographically restricted in a specific habitat. This species is a resprouter predominantly found after fire, but its seed production is unknown.