An evaluation of the Cactaceae of Barbados, Grenada, Saint Vincent, and The Grenadines Hoxey, Paul Gdaniec, Andrew Phytotaxa 2021 2021-02-05 483 1 25 74 6T3JY (Ker Gawler) Haworth (1819: 79) Haworth 79 1819 Ker Gawler [165,741,1877,1904] Magnoliopsida Cactaceae Opuntia Plantae Caryophyllales 24 49 Tracheophyta species dillenii   Type:—not stated but in cultivation in London (not preserved).   Lectotype(designated by Benson 1969: 126):—[icon] t. 255 in Ker Gawler (1817, image of the lectotypeavailable at https://www. biodiversitylibrary.org/item/9039#page/251).   Description:—Plantforming extensive clumps of spreading pads ( Fig. 24). Jointsobovate to oblong, epidermis blueish green and glaucous. Areoles evenly spaced with white felt. Spinesstout, 2–10, usually curved, yellow. Glochidsnumerous, yellow, appear from upper edge of areoles only (but occasionally absent). Flowersusually appear on the edge of the pads. yellow (orange-yellow on Barbados) petals. Fruits(when mature) 7–9 cmlong, purple red, juicy red pulp, usually spineless but with numerous glochids.   Distribution in the study area ( Figs. 2F–2I):—  Opuntia dilleniiis found on most of The Grenadinesand Grenada, but not on Saint Vincent. It also occurs on Barbados. On Barbadoswe only found the species on the north coast of the island, growing on coral limestone and in the Scotlandsandstone district.  General distribution:—This species is widespread in the Lesser Antilles and Greater Antilles.   Discussion:—We agree with the taxonomic treatment by Howard (1989: 412)and Taylor & Zappi (2004: 192)who recognized  Opuntia dilleniias a separate species widespread in the Caribbean region. On the other hand, Hunt et al.(2006: 202)suggested it may just be a spiny form of  Opuntia stricta. We consider  O. dilleniias a native species of the Lesser Antilles. Note however, that the fruit is sweet, edible, and a useful as food source, so it may have been introduced by human at least in some sites. Early settlers could easily have dispersed this species by transporting pads as they travelled amongst the islands. Nevertheless, it is probably dispersing itself naturally now as we encountered the species on small islands of difficult access (e.g. Pigeon island off Bequia) which is unlikely to have been inhabited, and local people take little interest in the plant today. The flower of  Opuntia dilleniiis reported to be yellow, but on Barbadosit is orange-yellow coloured. We only saw flowering plants on Union Island ( Fig. 25) and Barbados( Fig. 26) and confirmed this observation. Most plants had green immature fruits but occasionally we found mature purple fruits ( Fig. 27).  Howard (1989: 415)reports  Opuntia wentianafrom Grenada, the only locality he notes in the Lesser Antilles. This is supported by the specimen R.A.Howard 18335(A01677346!) collected at Pointe Saline. We failed to find this species on Grenadaand we believe Howard’s specimen is probably a weakly-spined form of  O. dillenii, either growing in poor conditions or showing juvenile characteristics.  Specimens examined:— BARBADOS: 30 September, 1915, Rose 21180(US).  GRENADA.  30 March 1977, Howard 18335(A); Carriacou,  7–25 March 1950, Howard 10891(GH).  ST. VINCENT & THE GRENADINES. Bequia,  20 March 1977, Howard 18245(A). 1950-03-07 1977-03-30 1950-03-07 Grenada GRENADA 25 50 1 1977-03-20 Saint Vincent and the Grenadines Bequia 25 50 1