Piper acutistigmum C. DC. Candollea

Mukherjee, Prasanta Kumar, 2018, Nomenclatural notes on Piper Linn. (Piperaceae) from India II, Phytotaxa 338 (1), pp. 17-32 : 18

1. Piper acutistigmum C. DC. Candollea 2: 196. 1925

Type:— MYANMAR: Upper Burma, 1892, Abdul Huk s.n. (holotype CAL!, 00000246674)

Distribution:— INDIA: Andaman Islands, Arunachal Pradesh (?); MYANMAR.

Note: —This species was originally described from Myanmar. Its extended distribution from the Andaman Islands is reported here. The specimen referable is “N. Andaman, Betapur, 25 March 1916, C. E. Parkinson 1134 (CAL!)”. It resembles exactly the type in foliage. The report of the species from Arunachal Pradesh ( Gajurel et al. 2002, 2008) seems doubtful, as the figure no. 3.16 (2008) is similar to P.lainatakanum C. DC. (1912: 519) . Leaves in P.acutistigmum are broadly ovate with a deeply cordate base and acute apex. They are oblong elliptic with a rounded slightly unequal base in P. lainatakanum . Piper acutistigmum has spikes maturing longer than lamina, 15 to 17 cm long and 2.5 to 3 cm thick, flexuous; bracts orbicular peltate, rachis hirsute, fruits globose, compactly placed being not seated in grooves. The Andaman specimen bears a male spike which is half the length of the lamina, erect, 5.5 cm long and 2 cm thick with densely packed flowers; bracts orbicular peltate, stamens 2. In P. lainatakanum , female spikes are thickened at maturity, shorter than lamina, up to 10 cm long and 4 mm thick; bracts peltate, basally attached and free at margins, obovate; fruits sparsely placed, not all maturing, seated in pits of the hirsute rachis, ovate; stigmas 3.