Agapetes linearifolia C. B. Clarke, 1882

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 : 110

Agapetes linearifolia C. B. Clarke in Hook. f. Fl. Brit. Ind. 3, 449, 1882 ( Figure 3 , A-F)

Type: China, Xizang, Zayu, Mishmi Hills, Thumath summit. 1836. Griffith 3480 (holotype K 000729427!).

Epiphytic shrubs up to ca. 0.5 m tall. Twigs slender, slightly drooping, with inconspicuous scattered lenticels, 1–2 mm in diam., glabrous. Leaves alternate and distichous; petioles robust, 2–4 mm long; leaf blades coriaceous, linearlanceolate, 10–15 × 0.7–1.3 cm, glabrous, apex acuminate, base attenuate to obtuse, margins entire and revolute, midvein raised abaxially, impressed adaxially, secondary veins inconspicuous, ca. 10 pairs. Inflorescences axillary corymbose, pendent, 3–8-flowered, 6–8 cm long; peduncle slender, coarsen at apex, 0.7–4.5 cm long, green; bracts small, at base of pedicels, inconspicuous; pedicels green to light pink, 2.2 cm long, 2–4 mm in diam., glabrous, cupshaped apically. Calyx light pink, campanulate, 6–7 mm long, glabrous, divided to middle; calyx tube 2–3 mm, calyx lobes triangular, 3–4 mm long. Corolla light pink, cylindrical-obconical, apex green to glaucous, 1.5–1.7 cm long; lobes triangular, ca. 1.3 mm long. Stamens 10, ca. 1.5 cm long; filaments, ca. 5 mm long, glabrous; anthers 9–10 mm long, thecae scabrous-papillate, ca. 4 mm long, tubules to 1.5 times as long as thecae, without spurs; Style ca. 1.4 cm long. Fruit subglobose, dull greenish yellow, ca. 1.4 cm in diam..

Phenology: Flowering in October to December and fruiting in May to June.

Distribution and habitat: China, India, Myanmar: Kachin state, where it is an epiphytic shrub that grows on the trees around the streamside of Nam Tsang, at 520 m a.s.l. ( Figure 6 ). It is newly recorded from Myanmar.

Specimens examined: Myanmar. Kachin State: NaungMung, streamside of Nam Tsang , 97º 48 ʹ 44.42 ʺ E, 27º 30 ʹ 20.44 ʺ N, alt. 520 m, 6 Dec. 2014, Myanmar Exped. 405 ( HITBC) ; Near Gathu village , 97º 58 ʹ 34.27 ʺ, 27º30 ʹ 31.98 ʺ N, alt. 625 m, 5 June 2018, Myanmar Exped. 3999 ( HITBC) .

Notes: All the descriptions of this rare and distinct species in Chinese provincial and national floras were based on Airy Shaw’s protologues (1935) due to lack of specimens. Airy Shaw’s original description was based on the type specimens collected in 1836 and F. Kingdon-Ward’s collection from Delei valley in April 1928 ( Airy Shaw 1935). We collected this species again in 2014, 86 years after Kingdon-Ward’s collection and nearly two centuries after the original discovery of the species by Griffith. The rediscovery of this species also represents the first time it has been found in Myanmar, so it is a new addition of an Agapetes species to the flora of Myanmar.

This species resembles Agapetes reflexiloba , A. nutans , A. angustifolia , and A. pseudo-griffithii ( Figure 3 , E-F) in its lanceolate leaf blades and its corymbose inflorescence, but they can be distinguished from each other by their pedicels and corollas. The differences between these four species are shown in Table 1.

Figures

FIGURE 3. Agapetes linearifolia. A. Habit; B. Flowering branch; C–D. Inflorescence; E–F. Fruiting branch. A. pseudo-griffithii. G–H. Fruiting branch. Photographed by Y.H. Tan, B. Yang, H.B. Ding & Yang Niu.

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.