Agapetes reflexiloba Y. H. Tan & Bin Yang, 2019

Yang, Bin, Ding, Hong-Bo, Zhou, Shi-Shun, Maw, Mya Bhone, Maung, Kyaw Win & Tan, Yun-Hong, 2019, Taxonomic studies on Agapetes in Myanmar I: Agapetes reflexiloba, a new species from Kachin State, and notes on three rediscovered species including two new records for Myanmar, Phytotaxa 393 (2), pp. 105-118 : 106-107

Agapetes reflexiloba Y. H. Tan & Bin Yang , sp. nov. ( Figure 1 )

Agapetes reflexiloba is morphologically similar to A. nutans Dunn , A. linearifolia C. B. Clarke , and A. angustifolia (Knagg) Airy Shaw in having linear to lanceolate narrow leaves and corymbose-racemose inflorescences ( Table 1). It is, however, readily distinguished from its three relatives by corolla lobes conspicuous reflexed in anthesis, corolla light brownish yellow to brownish yellow, and with 5 deep purple red zig-zag stripes.

Type: MYANMAR. Kachin State: Putao, near Namti, 97º 40 ʹ 6.36 ʺ E, 27º 25 ʹ 36.18 ʺ N, alt. 1,100 m, 14 Dec. 2017, Myanmar Exped. 3648 (holotype HITBC!, isotype RAF!).

Epiphytic shrubs up to ca. 1.2 m tall. Twigs terete, with conspicuous pale grey lenticels, 2–4 mm in diam., glabrous; young branches with linear bud scales, ca. 1–3 mm long, caducous. Leaves alternate; petioles 5–9 mm long, glabrous; leaf blades lanceolate, 7.5–10(–13.5) × 0.7–1.6 cm, apex narrowly attenuate to narrowly long caudate, base attenuate to obtuse, glabrous, margins entire and slightly revolute when dry, midvein raised abaxially, impressed adaxially, secondary veins inconspicuous, margin veins connected to a line. Inflorescences axillary, corymbose-racemose, 3–6- flowered, 6.5–7 cm long; peduncle 2–3.3 cm long, green, white wax on surface; bracts small, linear to subulate, 1–3 mm long; pedicels obconical, green to slightly light brownish yellow, 1.5–3.0 cm long, ca. 3 mm in diam. at apex, 1mm in diam. at base, glabrous, often white wax on surface; bracteoles basal, small, scale-like, triangular, ca. 1 mm long. Calyx campanulate, 9–11 mm long, glabrous, green to slightly light brownish yellow; calyx tube 5–6 mm long, 5–6 mm in diam., limb divided to middle; lobes triangular, 5 × 3–4 mm long. Corolla cylindrical or tubular, 2.2–2.4 cm long, glabrous, light brownish yellow to brownish yellow, deep purple red at base, and with 5 deep purple red zig-zag stripes; lobes broad ovate-triangular, ca. 4 mm long, purplish red to dark red, apex acuminate, strongly reflexed in anthesis. Stamens 10, 2.2–2.4 cm long; filaments flat, 3–4 × 1 mm, white to pink, glabrous; anthers ca. 2–2.2 cm, thecae dark red, 4–5 mm long, tubules dull brownish yellow, 1.4–1.6 cm long; without spur. Style ca. 2.3 cm long. Fruit unknown.

Phenology: Flowering in December.

Etymology: The species epithet refers to its strongly reflexed corolla lobes.

Distribution and habitat: Agapetes reflexiloba is so far known only from the type locality of Putao, Kachin state in north Myanmar, where it is an epiphytic shrub that grows on the trees in montane broadleaved forests, at an elevation of ca. 1,100 m ( Figure 6 )

Conservation status: In our preliminary field survey in Putao in 2017, we found only 3 individuals epiphytic on an understorey tree near around Namti and not far away from Putao. As no further information about its habitat and the number of mature individuals is available, the species is here assigned a preliminary status of Data Deficient (DD) according to the IUCN Red List Categories and Criteria ( IUCN 2012).

Figures

FIGURE 1. Agapetes reflexiloba Y. H. Tan & Bin Yang. A–B. Flowering branch; C–D. Inflorescence; E–F. Flower; G. Stamen; H. Flower dissection (from top to bottom and from left to right): corolla, stamen, style along with ovary and pedicel, calyx. Photographed by H.B. Ding & B. Yang.

FIGURE 6. Distribution of Agapetes reflexiloba, A. bhareliana, A. linerifolia, A. nana and A. pseudo-griffithii in Myanmar based on our field investigation and some specimen records.