Piper mullesua Buch.

Mukherjee, Prasanta Kumar, 2018, Nomenclatural notes on Piper Linn. (Piperaceae) from India II, Phytotaxa 338 (1), pp. 17-32 : 23-24

13. Piper mullesua Buch. -Ham. ex D. Don, Prodr. Fl. Nepal. 20. 1825

Type:— NEPAL, Narainhetty , 17 Jan. 1803, Buchanan-Hamilton s.n. (lectotype designated here BM000950696 image!; isotype CAL!) .

Homotypic synonym: Chavica mullesua (Buch.-Ham. ex D. Don) Miq. Syst. Piperac. 280. 1843.

Piper guigual Buch. -Ham. ex D. Don Prodr. Fl. Nepal 20. 1825.

Type :— NEPAL, Narainhetty, 6 Feb. 1803, Buchanan-Hamilton s.n. (lectotype designated here BM000950728 image!; isotype CAL!) .

Chavica guigual (Buch.-Ham. ex D. Don) Miq. Syst. Piperac. 280. 1843.

Chavica sphaerostachya Miq. Syst. Piperac. 278. 1843 non Piper sphaerostachyum DC. Prodr. 16: 326. 1869 non Chavica neesiana Miq. Syst. Piperac. 249. 1843 pro parte.

Type :— NEPAL, May 1821, Wallich 6656 (lectotype designated here U0016199 image!; isolectotype K000794464 image!; K001124429 image!–right hand specimen only; GZU000256185 image!, BM000950695 image!, G-DC G00207123 image! CAL!; syntype Java, Schmidt s. n. n. v.) .

Piper brachystachyum Wall. ex Hook. f. Fl. Brit. India 5: 87. 1886 non Vahl (1804: 354) pro syn. et non C. DC. Prodr. 16: 296. 1886 nom . illeg.

Type :— NEPAL, Pasputinath, May 1821, Wallich 6656 (lectotype designated here BM1088832 image!; isolectotype CAL!, G-DC G00207123 image!, K001124130 and 001124432 images!, MO0204014 image!) .

Chavica neesiana Miq. Syst. Piperac. 249. 1843 pro parte non Piper neesianum C. DC. Prodr. 16: 2565. 1869 nom illeg.

Type:— NEPAL, March 1821, Wallich 6656 (lectotype designated here K 001124432 image!).

Piper pleiocarpum Chang & Tseng Acta Phytotax. Sin. 17(1): 40. 1979 syn. nov.

Type:— China: Lan-tsang Hsien 2100 m. 05. 1936 C. W. Wang 76860 (isotypes P 00002937 image!. P 00002938 image!).

Piper nirjulianum Gajurel, Rethy & Kumar Rheedea 17: 35. 2007 nom . invalid; 2008:45. syn. nov.

Type:— INDIA, Arunachal Pradesh. Nirjuli Forest, 200m, P. R. Gajurel 95 (holotype CAL n. v.

Distribution:— INDIA: Assam, Arunachal Pradesh, Sikkim, West Bengal, Manipur, Andhra Pradesh, Tamilnadu, Kerala, Karnataka, Uttarakhand, CHINA, BHUTAN; MYANMAR, NEPAL.

Note:— Buchanan - Hamilton’s specimens, for both P.mullesua and P. guigual , are present at BM and are considered as holotypes for the two names, respectively. Specimens on the two sheets, bearing only ovoid fleshy compact head-like spikes are identical in general appearance and hence they were correctly considered as synonymous by Long (1984: 347). The twigs appear to be of low shrubby plants.

Wallich’s material is notoriously mixed. Wallich 6656 from Nepal has been used by Miquel (1843: 249, 278) differently. A major part of this formed the basis of Chavica sphaerostachya and only a minor faction was named by him as Chavica neesiana Miq. (= P. peepuloides Roxb.(1820: 159) . This part is represented by a sheet at K (001124432). Miquel (loc.cit.) described Chavica sphaerostachya as a scandent species. Wallich 6656 from Nepal was included in Wallich’s catalogue as P. brachystachyon Wall. , an unpublished name. The name P. brachystachyon was however changed to P. brachystachyum and was validly published by Hooker (1869: 87) to create a later homonym of P. brachystachyum Vahl (1804: 354) . Wallich 6656 as present at BM, CAL, G-DC, K and MO possesses ovoid fleshy compact head-like spikes like those on P. mullesua and P. guigual . Leaves are similar in all these taxa mentioned. Unfortunately, dioecy like other species of Piper from India is not definitely evident in all these taxa. Piper nirjulianum Gajurel, Rethy & Kumar (2007: 35) appears similar to P. mullesua based on the description and figures provided by the authors, but the holotype, presumably at CAL, has not been deposited there. P. arcuatum γ (var.!) quintuplinervium C. DC. Prodr. (1869: 360) may belong here.

This species is an enigmatic one and reported to be variable in its habit, differing from terrestrial or epiphytic, shrub to scandent, dioecious or hermaphrodite. J. D. Hooker (1869) and Gajurel et al. (2008) indicated that plants from northern and eastern India are shrubby, while those from peninsular India are woody climbers. Miquel (1845) illustrated female and male twigs of Chavica sphaerostachya . Gajurel et al. (2008) insisted that both the male and female plants are distinct. J. S. Hu (1999: 128) found that climbers carry bisexual flowers on subglobose spikes being partly immersed in rachis. The very small bisexual inflorescence are overlooked at anthesis. According to him, the description of the male inflorescence as slender and filiform by earlier botanists (Miquel, 1943; Wight, 1853; de Candolle, 1868; Hooker, 1886) was wrong. However, the protologue of P. pleiocarpum Chang & Tseng (1979: 40) indicate the same characters given for P. mullesua by these earlier botanists. The isotypes at P when examined show little difference. As such both are synonymised here. Interestingly, specimens from north-western Himalaya at CAL show the shrubby habit. Vicary has noted on the specimen (Dehra Dun, or hills above, Vicary s.n.) “…stamens 3–4, 1- celled, bursting at top (and becoming peltate?), filament thickly covered with long hyaline hairs, except near the base. At base of spadix found some naked stamens with 2-lobed anthers. Can these be the true stamens and the peltate bodies or corolla or of that nature? Or are these at the base abortive, the cells have not developed ….”. The observation can be vouched in other specimens from north west Himalaya but whether the stamens seen on them are functional or not has not been tested. Therefore, doubt remains as to whether the plants are dioecious, monoecious or incipiently dioecious. The dioecious nature of the plants in peninsular India, however, was confirmed by Miquel (1843), Hooker (1886) and Gamble (1921).

The ovoid spikes are very typical, with fruits packed on the inflated globular rachis being placed in individual grooves, lined by filamentous hairs. Orbicular peltate bracts are evident on younger spikes. A detailed study of this species is warranted.

This species is often confused with P. diffusum Vahl (1804: 333) in herbarium specimens at CAL. Several of these were annotated as such by C. de Candolle in 1911. Kanjilal et al. (140: 38) and Gajurel et al. (2008: 35) dealt with P. diffusum as a distinct species, being climbers from Assam and Arunachal Pradesh, respectively. Piper diffusum was based on Sirium frigidum Rumphius (1747: 345 , t. 119, f. 2). Vahl’s specimens at the Koenig herbarium, Copenhagen, are different from the Rumphius figure. Instead, they are similar to t. 119, f. 1 of the Rumphius’ icones. Interestingly, Miquel (1843: 280) has cited the latter illustration for Chavica guigual , which is currently held as synonymous to P. mullesua . Therefore, Vahl’s citation of Rumphius’ figure appears confusing. Merrill & Robinson (1917) could only identify it as a Piper sp. C . de Candolle (1869: 364) referred it to P. attenuatum Buch. -Ham. ex Miq.(1844: 306 nom illeg.) Vahl reported this from Sri Lanka and Miquel (1843: 327) referred it from Java and Amboina. Dassanayake & Fosberg (1987: 272–300) did not deal with the species from Sri Lanka. Hooker (1886) kept this as an undeterminable species. The identity of Piper diffusum and its locality remains unsettled. Reports of the taxon from Assam and Arunachal Pradesh by Kanjilal et al. (1940) and Gajurel et al. (2008) probably are based upon misidentification.