Dioscorea polygonoides Humb. & Bonpl. ex Willdenow (1806: 795)

Raz, Lauren, 2016, Untangling the West Indian Dioscoreaceae: New combinations, lectotypification and synonymy, Phytotaxa 258 (1), pp. 26-48 : 42

3. Dioscorea polygonoides Humb. & Bonpl. ex Willdenow (1806: 795) . Type:— Venezuela, Orinoco River . Humboldt & Bonpland s. n. (holotype: B-W; isotype: P-HBK)

Dioscorea lutea G. Meyer (1818: 282) . Type:— Suriname. Essiquibo, E.K. Rodschied 262 (holotype: GOET).

Dioscorea martinicensis (1822: 17). Lectotype (designated here):— MARTINIQUE. Without locality, Jun 1822, Sieber 27 (lectotype K!, isolectotype MO!). Dioscorea sieberi Kunth (1848: 58) . Dioscorea polygonoides var. sieberi (Kunth) Uline ex Knuth (1917: 208) . Dioscorea polygonoides var. martinicensis (Sprengel) Knuth (1924: 217) . The type is attributed to Sieber, but the K sheet is marked “legit. Kohaut”, referring to an associate of Sieber, who collected in Martinique from 1819–1821.

Dioscorea altissima Sieber ex Presl (1845: 546) , nom. illeg. (cited in synonymy of the following).

Dioscorea multiflora Presl (1845: 546) . nom. illeg.

Dioscorea polygonoides var. aperta Knuth (1917: 208) Type:— TRINIDAD & TOBAGO. Tobago: Campbleton Woods, 13 Nov. 1912, Broadway 4278 ♂ (holotype B!, isotypes E!, K!).

Dioscorea polygonoides var. scorpioidea Uline ex Knuth (1917: 208) . Lectotype (designated here):— PUERTO RICO. Sierra de Luquillo: Monte Jimenes, 1885, Sintenis 1729 ♂ (lectotype B!, isolectotypes LD!, S!). Remaining former syntypes: DOMINICAN REPUBLIC. Puerto Plata, no date, Eggers 2496 ♂ (B!); GRENADA. Without locality, 1905, Broadway 1747 ♂ (B!).

Dioscorea polygonoides var. cabreana Stehlé (1976: 447) . nom. illeg.

Dioscorea altissima auct. non Lamarck in Sieber ex Presl (1845: 546).

Notes: This species has essentially the same distribution as D. cordata in the Greater and Lesser Antilles, and also occurs throughout the lowland neotropics. While D. polygonoides is highly variable, the leaf outline is more stable than in D. cordata . Knuth’s varieties reflect differences in cymule architecture and width of the basal sinus, but do not correspond to any clearly observable patterns in either geographical or morphological space. Howard (1979) described local variants in the Lesser Antilles (without assigning to them formal taxonomic ranks), but further studies of this species are needed on a region-wide basis, including South and Central America. See Govaerts et al. (2015) for non WI synonyms.

Knuth (1917) described D. polygonoides var. sieberi and then cited it in synonymy under D. polygonoides var. martinicensis ( Knuth 1924) , the latter epithet being the older of the two. Knuth (1917, 1924) also cited “ D. lutea Griseb. nec Mey” in Grisebach (1864: 588) as a synonym of D. p. var. martinicensis , while he interpreted the Meyer name to be a synonym of “ D. polygonoides ” with no varietal name. Grisebach’s (1864) use of D. lutea was based primarily on examination of material from Antigua and Trinidad. Here no distinction is made between Meyer’s and Grisebach’s interpretations of this species in the Lesser Antilles.

Neither the 1917 protologue nor the 1924 monograph includes an explicit citation of the herbarium where the type of D. p. var. aperta is stored, however the B sheet is the only one annotated by Knuth, and is here interpreted to be the holotype.

Acevedo & Strong (2012) chose to include D. kegeliana Grisebach (1848: 279) among the synonyms of D. polygonoides , a decision apparently based on Govaerts et al. (2015). This name was based on material from Northern S. America (including Trinidad & Tobago) but is not mentioned in other sources of literature on the WI flora, and thus it has not been included here.