The number of species accepted varies between different authorities depending on taxonomic interpretation, but with a recent trend to reduce the number recognised as distinct. The recent
Flora of China (series) has cut the number accepted for China from 35 to seven species, and the
US Department of Agriculture recognises only two in the United States,
synonymising C. tomentosa with
C. alnifolia. The following are accepted by the
World Checklist of Selected Plant Families: •
Clethra acuminata – mountain pepper bush; S
Appalachians (
Alabama to
Pennsylvania) •
Clethra alcoceri –
Hidalgo,
Jalisco •
Clethra alexandri – Jamaica •
Clethra alnifolia – sweet pepper bush or summer sweet; S + E United States (
Texas to
Maine) •
Clethra arborea – lily of the valley tree;
Madeira,
Canary Islands†,
Azores •
Clethra arfakana –
New Guinea •
Clethra barbinervis – Japanese sweet shrub; SE China, Korea, Japan •
Clethra bodinieri – S China •
Clethra canescens – Philippines, E + C Indonesia, New Guinea •
var. clementis – Borneo •
Clethra castaneifolia – Peru •
Clethra chiapensis –
Chiapas •
Clethra consimilis – Panama, Costa Rica •
Clethra conzattiana –
Oaxaca •
Clethra crispa – Ecuador •
Clethra cubensis – Cuba •
Clethra cuneata – Peru, Bolivia •
Clethra delavayi – SW China,
Assam, Myanmar, Bhutan, Vietnam •
Clethra elongata – Peru, Bolivia •
Clethra fabri – S China, Vietnam •
Clethra fagifolia – Ecuador, Colombia, Venezuela •
Clethra fargesii – C China •
Clethra ferruginea – Peru •
Clethra fimbriata – Peru, Ecuador, Colombia •
Clethra formosa – Costa Rica •
Clethra fragrans – Jalisco,
Michoacán,
Guerrero •
Clethra galeottiana –
Puebla, Oaxaca, Chiapas •
Clethra gelida – Costa Rica, Panama, Honduras •
Clethra guyanensis – Guyana, Venezuela •
Clethra hartwegii – C + S Mexico •
Clethra hendersonii – Peninsular Malaysia •
Clethra hirsutovillosa – Guerrero •
Clethra hondurensis –
Tabasco to Costa Rica •
Clethra javanica –
Java,
Bali,
Lombok,
Timor •
Clethra kaipoensis – SE China •
Clethra kebarensis – New Guinea •
Clethra licanioides – Guatemala, Honduras •
Clethra longispicata –
Borneo, Philippines,
Sulawesi,
Maluku •
Clethra luzmariae – Oaxaca •
Clethra macrophylla –
Veracruz, Puebla •
Clethra mexicana – C + S Mexico, Central America, Colombia, Venezuela, Trinidad •
Clethra oaxacana – Oaxaca •
Clethra obovata – Ecuador, Peru •
Clethra occidentalis – Jamaica •
Clethra oleoides – C + S Mexico, Central America •
Clethra ovalifolia – Colombia, Venezuela, Ecuador, Peru •
Clethra pachecoana – Chiapas to Honduras •
Clethra pachyphylla – Borneo •
Clethra papuana – New Guinea •
Clethra paralelinervia – Ecuador •
Clethra × parvifolia – Chiapas •
Clethra pedicellaris – Colombia, Ecuador, Peru •
Clethra peruviana – Ecuador, Peru •
Clethra petelotii – Vietnam, Yunnan •
Clethra poilanei – Laos •
Clethra pringlei – Mexican summersweet – Mexico •
Clethra pulgarensis –
Palawan •
Clethra purpusii – Oaxaca, Chiapas •
Clethra pyrogena – Panama, Costa Rica •
Clethra repanda – Colombia, Venezuela •
Clethra retivenia – Peru •
Clethra revoluta – Colombia, Bolivia, Ecuador, Peru •
Clethra rosei – Mexico •
Clethra rugosa – Colombia, Ecuador •
Clethra scabra – Brazil, Bolivia, Paraguay, NW Argentina •
Clethra skutchii – Guatemala •
Clethra sleumeriana – Hunan •
Clethra suaveolens – S Mexico, Central America •
Clethra sumatrana –
Sumatra •
Clethra sumbawaensis –
Lesser Sunda Islands •
Clethra symingtonii –
Perak •
Clethra talamancana – Costa Rica •
Clethra tomentella – Philippines •
Clethra tutensis – Panama •
Clethra tuxtlensis – Veracruz •
Clethra uleana – S Brazil •
Clethra vicentina – S Mexico, Central America ==References==