Callerya chlorantha Mattapha & Sirich., 2016

Sirichamorn, Yotsawate, Balslev, Henrik & Mattapha, Sawai, 2016, Two new species of Callerya Endl. (Leguminosae: Papilionoideae) from Thailand, Phytotaxa 263 (1), pp. 42-50 : 44-47

1. Callerya chlorantha Mattapha & Sirich. , sp. nov. ( Fig. 2 , 3 )

Diagnosis:—Most similar to C. cochinchinensis (Gagnep.) Schot , but differing in having stipellae persistent (vs caduceus), no bracteoles, flowers 10–15 mm (vs 18–21 mm) and a different distribution (Kanchanaburi, south-western Thailand vs China and Vietnam).

Type:— THAILAND. Kanchanaburi: Sai Yok district, ca 6 km from and east of Mahidol University , Kanchanaburi Campus , in small, very disturbed and degraded dry bamboo-deciduous forest, with limestone rock, roadside, ca. 120 m elevation, GPS coordinate 14°06’50.4”N 99°12’04.0”E, 20 June 2014, Phutthai and Sirichamorn 2014-1 (holotype BKF!; isotypes BK!, K!, KKU!, L!, QBG!) .

Woody climber. Basal stem diameter 8–11 cm, twigs 6–8 mm diam., lower part lenticellate, glabrescent, upper part pubescent. Stipules minute, narrowly ovate or acicular, 2–4.5 mm long, 0.5–1 mm wide, caducous. Petiole 2.5–5 cm long, grooved above, pubescent; rachis 2.5–6 cm long, grooved above, pubescent; pulvinus 3–7 mm long, pubescent, stipellae persistent, filiform 1–2 mm long. Leaflets 5, light green when young, moderately pubescent, chartaceous, the terminal leaflet elliptic or obovate, 6–12 cm long, 3.5–8 cm wide, length/width ratio 1.4:1–1.9:1, base acute, apex with acumen up to 5 mm long, rounded or retuse, glabrescent above, glabrescent or with few hairs along midrib and veins below, midrib and veins raised in a furrow above and distinctly raised below, veins 7–9 per side, 5–20 mm apart, not reaching the margin but curving towards the apex, sometimes anastomosing near the margin, venation reticulate; lateral leaflets similar to the terminal one, elliptic to ovate, 4–10 cm long, 2–5.5 cm wide, length/width ratio 1.8–2; pulvinus c. 3 mm long, (thinly) pubescent. Inflorescences axillary or terminal panicles up to 30+ cm long, peduncle 1–3.5 cm long, (thinly) pubescent; primary or secondary lateral branches up to 15 cm long. Bracts subtending lateral branches narrowly ovate 1.8–4 mm long, 0.5–1 mm wide, caducous, or become leaf-like, persistent; floral bracts as long as flower buds, narrowly elliptic or narrowly ovate, 3–5 mm long, 1–1.8 mm wide, abaxially sericeous, adaxially glabrous. Pedicels 3–6 mm long, sericeous. Bracteoles absent. Calyx greenish, cup-shaped, 4–6 mm long, tube ca. 4 mm long with 4–5 lobes; upper lip inconspicuously lobed to 2-lobed, lobes semicircular, 0.7–1 mm long, 1.5–2 mm wide, sometimes indistinct, 2 lateral lobes triangular, 1–1.5 mm long, 1–2 mm wide; lower lobe triangular, ca. 1–2 mm long, 1–1.5 mm wide; abaxially sericeous, adaxially glabrous. Corolla pale green, standard with green central patch. Standard petal: claw 2–2.5 mm long; blade broadly obovate or orbicular, 8–10 mm long, 9–10 mm wide, apex slightly emarginate, abaxially sericeous, adaxially glabrous, with basal callosities. Wing petals: claw 1–1.5 mm long; blade spathulate or obovate, slightly oblique, 7–8 mm long, 2–3 mm wide, apex rounded, curved upward, both sides glabrous, upper auricle ca. 1 mm long, lower auricle absent. Keel petals: claw 3–3.8 mm long; blade obovate-navicular, 6–7 mm long, 3–3.5 mm wide, apex rounded, both sides glabrous; upper auricle 1–1.5 mm long, upper auricle and upper margin folded inwards. Stamens diadelphous, 8–10 mm long, free part 2–3 mm long, glabrous; anthers 0.7–1 mm long, 0.4–0.5 mm wide, glabrous. Disc tubular, ca. 1 mm high, glabrous. Ovary 5–7 mm long, sericeous; ovules 3–5; style 2–3 mm long, glabrous or thinly sericeous at base. Pods variable in shape but usually strap-like, 5–10 cm long, 1–1.8 cm wide, glabrescent, slightly contracted between the seeds; seed chamber absent. Seeds 1–3 per pod, lenticular, 10–12 by 9–11 by 3–5 mm; hilum slightly eccentric, ca. 2 mm long.

Phenology:—Flowering June to August, fruiting September to December.

Ecology:—Dry deciduous or bamboo forest along road side, growing in full sunlight, associated with lowland (up to 200 m) limestone habitat.

Distribution:—Endemic to southwestern Thailand (Kanchanaburi province) but could possibly also occur in Myanmar because its habitat crosses the border to that country.

Elevation:— 100– 200 m.

Proposed IUCN conservation assessment:— Known only from a small population (with fewer than c. 50 individuals) in Kanchanaburi, growing in roadside areas which are very easily disturbed or destroyed. Callerya chlorantha , therefore, appears to be a critically endangered species (CR B1a+2a; D) according to the red list criteria ( IUCN 2012). However, we do not have detailed data about distribution, abundance, or threats, and we expect that undiscovered populations of this species may exist: and it should therefore be considered Data Deficient (DD) at this time.

Etymology:— Reference to the green flowers of the species.

Figures

FIGURE 2. Callerya chlorantha: A. habitat; B. flowers and inflorescences; C. flowers (closed up), all from Phutthai and Sirichamorn 2014-1 (photos Y. Sirichamorn and T. Phutthai). Callerya tenasserimensis: D. habitat; E. flowers and inflorescences; F. flowers (closed up) all from Sirichamorn 2015-13 (photos Y. Sirichamorn).

FIGURE 3.Callerya chloranthaA. Habit; B, C. flower(top and sideview);D. standard,inside view; E.wing petal; F keel petal;G. stamens; H. pistil; I. pod; J1. seed, side view; J2. seed, front view, all from Phutthai and Sirichamorn 2014-1—Drawing by Y. Sirichamorn.