New species and new records of Artabotrys (Annonaceae) from peninsular Thailand

Abstract

Two new species of Artabotrys (Annonaceae) are described from peninsular Thailand. Artabotrys longipetalus J.Chen & Eiadthong, sp. nov., is unique among Artabotrys species in Thailand in having linear petals, relatively long flower pedicels and sessile monocarps. Artabotrys insurae J.Chen & Eiadthong, sp. nov., resembles Artabotrys uniflorus (Griff.) Craib, but can be distinguished by its oblique leaf base, flat petal blades, apiculate anther connective apex and the presence of a monocarp stipe. In addition, two new records for the Flora of Thailand are reported, viz. Artabotrys crassifolius Hook.f. & Thomson and Artabotrys pleurocarpus Maingay ex Hook.f. & Thomson; both species are so far only known from peninsular Thailand. A key to the 20 species of Artabotrys in Thailand is provided.

Artabotrys chitkokoi (Annonaceae), a new species discovered in Sagaing Region, Myanmar

“…The peduncle of A. chitkokoi sometimes does not resemble a hook; although the hook‐like peduncle is generally characteristic of Artabotrys , the peduncle morphology may be variable, sometimes even within a single individual (Chen and Eiadthong 2020). A fruiting specimen collected from Lower Chindwin (Lace 4166) was formerly mislabeled as A. kurzii , and here re‐identified as A. chitkokoi .…”

“…The majority of the species are found in Asia, with roughly 37 species in Africa (including Madagascar), and one species in northern Australia (Chen et al 2019). Turner (2018) lists 74 Artabotrys species for the Asia–Pacific Region, and two more species were recently added by Chen and Eiadthong (2020). The genus is be easily recognized by its hook‐like inflorescence axis, which is an unique adaptation in the Annonaceae for climbing.…”

“…Apart from the distinctive inflorescence hooks, the genus often possesses a raised midrib on the leaves (Turner and Utteridge 2015). The petals of Artabotrys can be divided into two parts: an upper, generally laminar (or terete) region known as the blade, and a basal, concave region known as the claw (Chen et al 2020). In Myanmar, the genus is represented by seven species (viz.…”

Artabotrys angustipetalus (Annonaceae), a new species from Thailand, including a plastid phylogeny and character evolutionary analyses of thorn occurrence in Artabotrys

“…: Artabotrys angustipetalus from Thailand, thorn occurrence in Artabotrys organs, (3) biovulate carpels, with basal placentation and (4) sessile to shortly stipitate monocarps (Keßler 1993;Chen & al. 2018;Chen & Eiadthong 2020). Species of Artabotrys develop a climbing habit with the help of hooked peduncles and inflorescence axes, but sometimes appear as straggling shrubs (e.g.…”

“…2018). In Thailand, there are 20 species of Artabotrys reported, two of which have recently been described (Chen & Eiadthong 2020). However, based on personal observations, identification of some specimens is still unsatisfactory due to the morphological heterogeneity of certain species, e.g.…”