Alphonsea glandulosa Y. H. Tan & B. Xue 2017, sp. nov.
Creators: name: Xue, Bine
name: Shao, Yun-Yun
name: Saunders, Richard M. K.
name: Tan, Yun-Hong
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Magnoliales
Annonaceae
Alphonsea
Alphonsea glandulosa

description: Alphonsea glandulosa Y.H. Tan & B. Xue, sp. nov. [urn:lsid:ipni.org:names:77159533–1] (Figs 2, 3, 4, 5 and 6)
Type: CHINA. Yunnan Province, Meng-la County, Meng-lun, Man-zhang Reservior, 21˚ 55 0 53 @ N, 101˚10 0 58 @ E, alt. 625 m. Y. H. Tan 1014*, 2016.04.07 (fl.) (holotype HITBC; isotypes IBSC, KUN)
Diagnosis. Alphonsea glandulosa is unique amongst Alphonsea species in having a nectar gland at the base of the adaxial surface of each inner petal. It is most similar to A. philastreana (Pierre) Finet & Gagnep., but differs in having a greater number of secondary veins on each side of the leaf, greyish to yellowish pubescent flower buds, longer pedicels, a greater number of carpels per flower, a smaller number of ovules per carpel, and globose to shallowly bilobed stigmas.
Description. Trees to 15–20 m tall, ca. 25–30 cm dbh. Bark brownish, fissured. Young twigs green, puberulent, soon become greyish and glabrous. Petioles 3–8 mm long, 1–2 mm in diameter, transversely densely striate; leaf laminae narrlowly elliptic, elliptic or ovate, 6–19 × 3–6.7 cm, base cuneate, apex acuminate, slightly coriaceous, abaxially sparsely pubescent to glabrescent, adaxially glabrous; midrib impressed and glabrous above, raised and hairy to glabrous below; secondary veins 8–18 on each side of the leaf, parallel, diverging at 45–60˚ from midrib, anastomosing within margin, distinctly raised below; tertiary veins reticulate, prominent abaxially. Inflorescences leaf-opposed or supra-axillary; (3–)5–9(–13) flowers per inflorescence (Fig 2A–2C). Peduncles absent or up to 3 mm long (Fig 2A–2C). Pedicels 10–20 mm long, 1–1.5 mm in diameter, pubescent, with one densely pubescent median bract (Fig 2A–2C). Sepals ovate, 1.5–2 × 1.5–2.5 mm, hairy abaxially, glabrous adaxially; outer petals ovate, 10–14 × 6–8.5 mm, base acute, apex acute, tomentose abaxially, sparsely hairy to glabrous adaxially; inner petals narrower, 10–14 × 5–8 mm wide, hairy abaxially, glabrous adaxially, with glandular tissue near the base (Fig 4A–4D), apparent as ridge in fresh (Fig 4A and 4B) and FAA-fixed (Fig 4C) material, and as distinct groove in dried specimens (Fig 4D). Stamens ‘miliusoid’ with very short connective prolongation not extending over pollen sacs, 26–35 per flower, ca. 1 mm long, in 3 whorls (Figs 3C, 4A and 4F). Carpels 4–7 per flower, ca. 3 mm long, with short brown hairs (Figs 2B and 4B); ovules 10–13 per carpel, biseriate (Fig 3D). Fruiting pedicels 7–20 mm long, 3 mm in diameter; monocarps 1–7 per fruit, subglobose to cylindrical, ca. 2–4 cm long, 1.5– 3 cm in diameter, yellow when mature, greyish pubescent, smooth, sometimes with a longitudinal ridge or
groove, apex rounded; stipe to 10 mm long, ca. 4 mm thick (Fig 2D and 2E). Seeds flattenedellipsoid, up to 13 per monocarp (Fig 2E). Pollen grains solitary, subspherical, 30–40 μm in diameter, rugulate (Fig 3E and 3F).
Etymology. The specific epithet reflects the presence of nectar glands at the base of the adaxial surface of each inner petal.
Additional specimens examined (paratypes). China. Meng-la, Yunnan, 2009-03-25, Chun-fen Xiao C100647 (HITBC); 2015-04-29, B. Xue 188 (IBSC); 2016-04-26, B. Xue 26* (IBSC, KUN); 2016-04-27, B. Xue 268 (IBSC, SING).
Distribution. Only known from two localities in Yunnan, China (Fig 7).
Ecology and phenology. In evergreen forests. Flowering specimens collected in March to May, and fruiting specimens in June to July.
IUCN Conservation Status. Only two individuals were found in Meng-la County, Yunnan Province. The primary forests in Xishuangbanna have been under severe pressure from agricultural expansion over the last 30 years, and below 900 m elevation most unprotected forest has been replaced by rubber plantations [57]. The tree growing in the forests close to Man-zhang Reservoir in Meng-la County is located at the edge of a rubber plantation. One of the authors, Yun-Hong Tan, has undertaken an extensive field survey in Xishuangbanna, but was unable to locate other individuals. Perhaps because of the dearth of individuals, the level of fruitset in the two trees is poor. On the basis of current IUCN red list categories and criteria [58], we therefore recommend critically endangered status, CR D.
description: Published as part of Xue, Bine, Shao, Yun-Yun, Saunders, Richard M. K. & Tan, Yun-Hong, 2017, Alphonsea glandulosa (Annonaceae), a New Species from Yunnan, China, pp. 1-16 in PLoS ONE (e 0170107) (e 0170107) 12 (2) on pages 11-13, DOI: 10.1371/journal.pone.0170107, http://zenodo.org/record/12630690