Piper subcanirameum C.DC.

Gardner, R. O., 2013, Piper (Piperaceae) in New Guinea: the climbing species, Blumea 57 (3), pp. 275-294 : 289-291

15. Piper subcanirameum C.DC. — Fig. 2j– s , 4g, 8b; Map 2

Piper subcanirameum (‘ subcaniramum ’) C.DC. (1923) 196,(1925) 221; Chew (1992) 163. — Type: Boorsma 7 (holo BO n.v.), New Guinea .

Piper trombek P. Royen (1982) 1278. — Type: Wheeler, ANU 6408 (holo L; iso CANB).

Fertile-shoot internodes c. 1–1.5 mm diam, nearly smooth. Vegetative parts entirely glabrous. Stipule to c. 1 cm long. Leaf blade subcoriaceous, ovate, c. 5 –11 by 2 – 5 cm; base symmetrical, rounded or truncate-cuneate, margins subequal at petiole and usually smoothly decurrent there down into edges of petiole; apex acuminate; main lateral nerves 2 pairs, one pair basal, the upper pair leaving midrib (often both nerves together) within proximal 1/5 of blade, all nerves strongly prominent above; glands very indistinct on both surfaces of blade. Petiole c. 0.5 –1 cm long, c. 1/10 as long as blade. Male inflorescence a spike 3– 4.5 cm long, c. 0.2 cm diam, on a peduncle c. 0.5 cm long; stamens 2/3 (?), anthers slightly exserted beyond bract-heads, c. 0.4 mm diam, dehiscing laterally. Infructescence 2 – 4 cm long, c. 6 mm diam, on a peduncle 0.5 –1.5 cm long; bracts subsessile, orbicular, c. 1 mm diam, glabrous; fruitlets usually fully fused with one another (but sometimes wholly or partly free), c. 1.5 mm diam, low-rounded above; stigmas 3, (sub)sessile, broad-oblong, together usually 0.4–0.7 mm diam.

Distribution — New Guinea, mainly the Highlands Region, also Finisterre Range (Madang Province) and Morobe Province; apparently absent from the Bismarck Archipelago.

Habitat& Ecology — In montane forest,(2000–) 2500–3620 m altitude.

Notes — The species resembles P. arfakianum in its rather small, coriaceous leaves; see Notes under that species for some distinguishing features. The two are found together in the vicinity of Mt Kaindi and Edie Creek (Morobe Province), from c. 2050 m ( LAE 60357, NGF 30885) to c. 2450 m ( P. arfakianum ; NGF 32863) and 2650 m ( P. subcanirameum ; Durand & Nelson 146).

The female inflorescences differ especially in that the fruitlets of P. arfakianum are usually free. However, Takeuchi 5756 (Mt Wilhelm, 2800 m, A, B, BISH) and Takeuchi 20136 (Porgera, 2900 m, A) are clearly P. subcanirameum by their leaves, but have mature spikes with substantially free fruitlets (Fig. 4g). I accept both as representing this species, though possibly they are aberrant.

De Candolle (1925) simply noted the type of P. subcanirameum as being from “New Guinea ”, and gave no date of collection. Chew (1992: 163) assumed it came from West New Guinea (Irian Jaya), making it the only such collection he cited for that part of the island. I have not seen any from there myself, nor is the species recorded for Mt Jaya (Carstenz) by Johns et al. (2006). Van Royen (1982) did accept for his P. trombek two collections from Lake Habbema in West New Guinea, Brass 9134 and 9308. I am not sure of their identity but at least the former is not P. subcanirameum .

a

c

With respect to a possible type locality for P. subcanirameum we should consider the statement by Van Steenis-Kruseman (1950: 71) that “New Guinea Pipers were collected on his [W.G. Boorsma, fl. 1891–1922] behalf”. Unfortunately, consideration of the identities of the nine consecutively numbered Piper specimens under Boorsma’s name ( De Candolle 1925, Chew 1972: 22) does not narrow the field. Nevertheless I speculate that the type is from the eastern rather than the western part of the island, with the most likely such locality being the Huon Peninsula mountains, explored botanically by C. Keysser in 1909 –1916 (Van Steenis-Krusemann 1950: 279).

Chew (1992) compared the types of P. subcanirameum and P. trombek and found no significant differences.

Van Royen (1982) included in his P. trombek two collections from the Mt Suckling complex (Northern Province), LAE 54062 and 55677. I have seen a duplicate of the latter at A (Tantam Plateau, 1980 m). It is small-leaved and completely glabrous and does not have the usual texture of P. subcanirameum . I cannot identify it (the inflorescences are in poor condition), and so omit both these collections from the mapped distribution.

Van Royen (1982) described the fruits of P. trombek as orange or yellow, in agreement with other label-notes for P. subcanirameum , which generally just state ‘fruit green’ (at least, I have seen none that say ‘fruit red’). Three collections with what seem to be ripe fruits describe their colour as ‘dull yellow’ ( Clemens 7605), ‘dull buff’ ( Clemens 7556) or ‘orange’ (NGF 24994).

Figures

Map 2 Distribution of Piper subcanirameum C.DC. in New Guinea. Rep- resentative specimens.

Fig. 2 Piper species.Fertile-shoot leaves and female inflorescence (‘infr.’),immature infructescence (‘infl/fr’) or ripe infructescence (‘infr.’). — a–i: P. arfakianum C.DC.; a. Brass 5029, Mt Tafa 2400 m, infl.; b. Brass 22534, Mt Dayman 2200 m, infl./fr.; c. Brass 22729, Mt Dayman 2150 m, infr.; d. Kanehira & Hatusima 13708, Angi 2200 m; e. Kostermans 2382, Angi Lake, 1800 m; f. LAE 60357, Mt Kaindi 2057 m, infr.; g. NGF 23627, Mt Kaindi 2300 m, h. NGF 30867, Mt Kaindi 2150 m, infr.; i. Sleumer & Vink 4433, Angi Lake 1950 m, infr. — j–s: P. subcanirameum C.DC.; j. Clemens 11215 p.p., Matap, Morobe Prov. c. 1600 m, infl/ fr.; k. Durand & Nelson 146 (HUH herb. Gray), Mt Kaindi 2650 m, infr.; l. LAE 57084, Ialibu 2515 m; m. NGF 19985, Edie Creek 2950 m, infr.; n. NGF 24994, Ialibu 2000 m, infr.; o. NGF 30885, Edie Creek 2050 m, infr.; p. Schodde 1861, Mt Giluwe 3050 m; q. Takeuchi 5756, Mt Wilhelm 2800 m, infl/ fr.; r. Takeuchi 10702 (BRIT), Bismarck Range 2040 m; s. Takeuchi 20136, Porgera 2900 m, infr. (all from A except as noted). — Scale bar = 5 cm.