Piper anisotis Hook. f. Fl. Brit.

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

2. Piper anisotis Hook. f. Fl. Brit. India 5(13): 86. 1886

Type:— INDIA: Arunachal Pradesh, Upper Assam, Thaumathya, Mishmi hills, Griffith 4416 (lectotype designated here K 000794473

image!; isolectotype K 000794472 image!). Piper hapnium Buch. -Ham. ex Hook. f. Fl. Brit. India 5(13): 86. 1886. nom . illeg. pro parte syn.nov. Type:— BANGLADESH: Phuranbari, Hamilton 101 in Wallich 6650D (lectotype designated here E 00313766 image!; isolectotype

K 001124413 image!–left hand specimens).

Distribution:— INDIA: Assam, Sikkim, Arunachal Pradesh; BANGLADESH (Rangpur).

Note: —J. D. Hooker (1886: 86) circumscribed Piper anisotis based on two Griffith 4416 specimens which differ from one another in the details of locality. Both locations essentially indicate present day Arunachal Pradesh. These two specimens are similar to one of the syntypes of P. hapnium (Hamilton 101), collected from Bangladesh and included under Wallich 6650D. Piper hapnium Hook. f. was published as a replacement name for Piper arnottianum (Miq.) C. DC. (1869: 352) . The rationale for Hooker’s action was the assumption that C. de Candolle circumscribed his taxon using material entirely different from those of the basionym Chavica arnottiana Miq. (1843: 268) . However, Hooker (loc. cit.) cited P. arnottianum (Miq.) C. DC. as a synonym and by implication included its types. Therefore, his name is nomenclaturally superfluous and illegitimate (McNeill et al., Art. 52.1, 52.2). A sheet of P. hapnium at K with the label “Phuranbari, 8th Feb., 1809” includes two distinct specimens, one marked as Wallich 6650 D (plants on the left, K001124413) and the other as Wallich 6650F (plant on the right, K001124414). Leaves of the plants on the left are similar to fragments of Hamilton 101 from Phuranbari (E 00313766), which shares the same date but is stored there wrongly under the name P. betleoides C. DC. (1925: 207) . Hooker also commented about specimens Wallich 6651A and 6651B (syntypes for Chavica arnottiana ) as well as 6643C. However, on examination these specimens are found to be different from Wallich 6650 D.

Both Wallich 6650 D and Griffith 4416 were collected from more or less adjacent phytogeographical areas (Arunachal Pradesh and Bangladesh (Rangpur )). Chavica arnottiana on the other hand was based on materials collected from Peninsular India, Travancore, Kerala to be precise. Types of P. anisotis are in fruit but such structures are absent in specimens of P. hapnium . Otherwise, both taxa share remarkably similar leaves. Leaves of Piper hapnium sensu Hamilton 101 and P. anisotis are superficially similar to those of P. arnottianum . Those in the former two are more unequal at the sessile to sub-sessile auricled base, and the auricle is larger on the basiscopic side. These leaves also have prominent reticulations that are adpressed adaxially and raised abaxially. Therefore, P. anisotis is merged with that part of P. hapnium which includes Hamilton 101 (listed as Wallich 6650D) only. Since the name P. hapnium is superfluous and illegitimate, the only other name available is P. anisotis . It is considered as the correct name for the species. The specimen Griffith 4416 at K (000794473) is perfectly preserved with distributional data mentioned by Hooker (1886) and therefore is designated here as the lectotype of P. anisotis . Further comments on P. arnottianum and P. hapnium are included in the note for P. arnottianum .