Peliosanthes macrophylla var. assamensis, 2020
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publication ID |
https://doi.org/10.3767/blumea.2020.65.02.05 |
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persistent identifier |
https://treatment.plazi.org/id/03D88785-1370-E67E-FC8C-FC40DDB42438 |
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treatment provided by |
Felipe |
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scientific name |
Peliosanthes macrophylla var. assamensis |
| status |
var. nov. |
b. var. assamensis N.Tanaka & D.Borah View in CoL , var. nov. — Fig. 2 View Fig , 3 View Fig ; Map 1 View Map 1
Peliosanthes macrophylla var. assamensis is distinguishable from var. macrophylla mainly by the staminal corona internally converging proximally and protruding near the middle, shorter anther thecae somewhat divergent distally, and longer, papillulate pistils exceeding anthers. — Type: D. Borah 2032 (holo ASSAM; iso ARUN), India, Biswanath District, Behali Reserve Forest, Siklibandha Tiniali, N26°54'23.9" E93°16'20.7"; 99 m, 12 Mar. 2019.
Etymology. The varietal epithet refers to the state, where the type locality belongs.
Stem 3–4 cm diam. Roots rigid, semi-woody, profusely branch- ed. Leaves few to many (over 20). Flowering stem (including peduncle and inflorescence rachis) up to 35 cm tall; peduncle 5–16.5 cm by 2–5 mm; inflorescence rachis up to 18 cm long. Perianth segments 5.5–6.5 by 3–4 mm. Staminal corona 3–4 mm long, 3.5–5 mm diam, internally connivent proximally and protruding near the middle, apical opening 2–3 mm diam; anthers 1–1.5 mm long, thecae somewhat divergent distally. Pistil 4–5 mm tall (excluding sunken part, entirely 5–7 mm tall), papillulate towards base; ovary ovoid to conical, 1–3 mm high (excluding sunken part, entirely 2–4 mm high), 2–3 mm wide; style subterete, trigonous, intercarpellary portion swollen around middle, c. 3 mm long, nearly equal to or slightly longer than exposed part of ovary; stigma exserted beyond anthers.
Distribution — NE India (Assam) . Currently known only from the type.
Habitat & Ecology — A component of the semi-evergreen patches of Behali Reserve Forest of Assam. It grows on the forest floor along with Ophiopogon micranthus Hook.f. , Chlorophytum assamicum D.Borah & A.P.Das , Tupistra stoliczkana Kurz , Dracaena petiolata Hook.f. ( Asparagaceae ); Achyrospermum wallichianum (Benth.) Benth. ex Hook.f. , Clerodendrum laevifolium Blume , Gomphostemma niveum Hook.f. ( Lamiaceae ); Magnolia hodgsonii (Hook.f. & Thomson) H.Keng ( Magnoliaceae ); Morus macroura Miq. ( Moraceae ); Tropidia angulosa (Lindl.) Blume ( Orchidaceae ) and many others. Flowering: March to April; fruiting: April to October.
Conservation status — Since this variety is only known from one locality (of more than 500 individuals scattered throughout the forest), a preliminary conservation status of Data Deficient (DD) seems appropriate ( IUCN 2019).
Notes — Because of large leaf blades with numerous longitudinal veins and very indistinct transverse veinlets, the novelty here described is no doubt close to P. macrophylla . The dif- ferences with the type variety are mentioned in Table 1. Our material from Arunachal Pradesh have upright long anthers 2–2.5 mm long, and comparatively short glabrous pistils not exceeding the anthers, which agree with specimens from Sikkim, India , collected by Hooker (K000099377, K000099378). In con- trast, P. macrophylla var. assamensis has shorter, distally somewhat divergent anthers 1–1.5 mm long and longer, papillulate pistils exceeding the anthers.
Since Peliosanthes has a staminal corona that largely covers the pistil and anthers, the variation in structure inside the corona has often been overlooked. The present discovery of var. assamensis indicates that P. macrophylla is differentiated in this floral structure among populations. It appears that further studies based on living specimens from various localities are needed to elucidate the intraspecific variation of P. macrophylla .
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