Piper dilatatum
Content
Description
Shrub or subshrub to 4 m tall. Stem crisp-pubescent or scabrous. Prophyll densely pubescent. Petiole 0.5-1.5 cm long, pubescent sometimes densely so, vaginate to apex, occasionally reddish tinged; blade hardly to densely scabrous above, not glandular-dotted, rhombic, elliptic to subobovate, 15-20 x 7-9 cm, apex acuminate, base unequally attached to petiole difference 0.3-0.4 cm, unequally cordate, rounded or obtusish, upper surface glabrous to pubescent, veins pubescent, lower surface sparsely to densely pubescent; pinnately veined, secondary veins 5-6 per side, originating from lower 1/2 of primary vein, tertiary veins transverse and parallel reticulate. Inflorescence erect; peduncle 0.5-1 cm long, puberulent to glabrous; spike 7-8 cm long, white to yellow, not apiculate; floral bracts 0.7-0.8 mm in diam., densely marginally fringed; stamen connective narrow, anthers dehiscing laterally. Fruits trigonous, glabrous, or with some hairs at top, stigmas 3, sessile.
Distribution
Southern America, northeastern S America present
West Indies and northeastern S America; 43 collections studied (GU: 20; SU: 6; FG: 17).
Notes
Piper dilatatum and P. hispidum have superficial resemblance; they differ, however, in the shape and the scabrity of the leaves. In P. dilatatum the leaves are mostly rhombic and not strongly scabrous, whereas in P. hispidum they are elliptic or ovate and strongly scabrous. In P. dilatatum, the anthers open laterally and the connective between the thecae is not broadened. In P. hispidum, the connective is broadened and the anthers open apically. The prophyll in P. dilatatum is densely pubescent, while in P. hispidum it is glabrous with pubescent midvein. Burger (1971: 128) stated that the two taxa differ significantly in anther and fruit characters.
Piper pseudofuligineum C. DC. is closely related to P. dilatatum. It is a Central American taxon, maybe a somewhat more pubescent form adapted to drier habitats (according to Burger).
Piper taboganum C. DC. is considered conspecific with P. pseudofuligineum. The A.C. Smith collections 2416, 3451 and 3079 from S Guyana identified as Piper taboganum seem better assigned to P. dilatatum and fit well into the distribution of the latter.
Sandwith 1544 from Kyk-overal on the Mazaruni R., Guyana was identified as Piper grahamii Trel. It probably belongs to P. dilatatum. A final conclusion on P. grahamii as a synonym of P. dilatatum can only be drawn after study of Graham 277, the type specimen that was collected in the same locality.
Yuncker (1957: 233) cited Splitgerber 225 (L) as the only Suriname report of P. auritum Kunth; this collection, however, has to be included in P. dilatatum. Piper auritum is known from Mexico to Colombia.
Piper pseudofuligineum C. DC. is closely related to P. dilatatum. It is a Central American taxon, maybe a somewhat more pubescent form adapted to drier habitats (according to Burger).
Piper taboganum C. DC. is considered conspecific with P. pseudofuligineum. The A.C. Smith collections 2416, 3451 and 3079 from S Guyana identified as Piper taboganum seem better assigned to P. dilatatum and fit well into the distribution of the latter.
Sandwith 1544 from Kyk-overal on the Mazaruni R., Guyana was identified as Piper grahamii Trel. It probably belongs to P. dilatatum. A final conclusion on P. grahamii as a synonym of P. dilatatum can only be drawn after study of Graham 277, the type specimen that was collected in the same locality.
Yuncker (1957: 233) cited Splitgerber 225 (L) as the only Suriname report of P. auritum Kunth; this collection, however, has to be included in P. dilatatum. Piper auritum is known from Mexico to Colombia.