Taxonomic history Early history The earliest species of the genus described was
Cotyledon caespitosa, by
Adrian Hardy Haworth in 1803, which would later be known as
Dudleya caespitosa. The same species would later be described again as
Sedum cotyledon by
Joseph Franz von Jacquin in 1811, and in 1840
Thomas Nuttall described both
Echeveria pulverulenta (
Dudleya pulverulenta) and
Echeveria lanceolata (
Dudleya lanceolata). The differing generic placements of these early descriptions suggest that taxonomic disagreements over the genus had an early start, with some of these generic placements persisting even after the proper description of the genus by Britton and Rose. In the 1930s,
Alwin Berger revised the status of
Dudleya and
Stylophyllum into a sectional ranking within
Echeveria, while merging the
Hasseanthus genera into
Sedum. This was in part due to a belief that
Dudleya had evolved from
Echeveria radiating northward from Mexico, evidenced by the similar tubular corollas, while
Hasseanthus possessed aesthetic similarities to
Sedum, primarily flowers with broadly spreading petals.
Stylophyllum was believed to occupy a transitory position between
Dudleya and
Hasseanthus. These conclusions were widely accepted by botanists for the first half of the 20th century, until proper molecular and phylogenetic analyses began to appear.
Modern classifications and phylogenetic research Around 1993, one of the only literary treatments of the genus was written,
Paul H. Thomson's
Dudleya and Hasseanthus Handbook. Research in the 21st century has supported the hypothesis of
Dudleya's relation to
Sedum. Phylogenetic analysis has given weight to this hypothesis, concluding that
Dudleya is much closer to North American members of
Sedoideae than to Echeverioideae. The plant
Sedum spathulifolium, which co-exists with
Dudleya in Oregon and California, has been shown in multiple phylogenetic reconstructions to be a sister taxon to
Dudleya, although it may not be the true sister taxon, as larger samplings are needed. Berger's hypothesis of a relationship between
Hasseanthus and
Sedum may still prove true, as in addition to morphological similarities, the
Hasseanthus-type taxa could be basal to the genus. However, no truly conclusive evidence of significant divergence within
Dudleya exists, and it remains unclear which groups are basal or derived.
Selected species •
Dudleya abramsii •
Dudleya abramsii subsp. abramsii – Abrams' liveforever •
Dudleya abramsii subsp. affinis – San Bernardino Mountains liveforever •
Dudleya abramsii subsp. bettinae – Betty's dudleya •
Dudleya abramsii subsp. calcicola – limestone dudleya •
Dudleya abramsii subsp. murina – Mouse-gray dudleya •
Dudleya abramsii subsp. setchellii – Santa Clara Valley dudleya •
Dudleya acuminata – Vizcaino liveforever •
Dudleya albiflora– White-flower liveforever •
Dudleya anomala – Todos Santos liveforever •
Dudleya anthonyi – Anthony's liveforever •
Dudleya attenuata – Orcutt's liveforever, tapertip liveforever •
Dudleya arizonica – Arizona chalk dudleya. Formerly a subspecies of
Dudleya pulverulenta. •
Dudleya blochmaniae – Blochman's liveforever, Blochman's dudleya •
Dudleya brevifolia – Short-leaved liveforever, short-leaved dudleya. Formerly a subspecies of
D. blochmaniae. •
Dudleya brittonii – Britton's dudleya, giant chalk dudleya •
Dudleya caespitosa – Coast dudleya, sea lettuce, sand lettuce •
Dudleya campanulata – Punta Banda liveforever •
Dudleya candelabrum – Candleholder liveforever •
Dudleya candida – Coronados liveforever •
Dudleya cedrosensis •
Dudleya crassifolia – Thick-leaf dudleya •
Dudleya cultrata – Knife-leaved liveforever, maritime succulent liveforever •
Dudleya cymosa – Canyon liveforever •
Dudleya cymosa subsp. agourensis – Agoura Hills dudleya •
Dudleya cymosa subsp. crebrifolia – San Gabriel River dudleya •
Dudleya cymosa subsp. costatifolia – Pierpoint Springs dudleya •
Dudleya cymosa subsp. cymosa – Coast Range dudleya •
Dudleya cymosa subsp. marcescens – Marcescent dudleya •
Dudleya cymosa. subsp. ovatifolia – Santa Monica Mountains dudleya •
Dudleya cymosa subsp. paniculata – Diablo range dudleya •
Dudleya cymosa subsp. pumila – Transverse ranges liveforever •
Dudleya densiflora – San Gabriel Mountains liveforever •
Dudleya edulis – Fingertips, lady fingers, San Diego dudleya •
Dudleya farinosa – Bluff lettuce, powdery liveforever, powdery dudleya •
Dudleya formosa – La Mision liveforever •
Dudleya gatesii – Gates' liveforever •
Dudleya gnoma – Munchkin dudleya •
Dudleya greenei – Greene's dudleya •
Dudleya guadalupensis – Guadalupe liveforever •
Dudleya ingens – Baja liveforever, rock liveforever •
Dudleya hendrixii – Hendrix's liveforever •
Dudleya lanceolata – Lanceleaf liveforever. •
Dudleya linearis – San Benito Island liveforever •
Dudleya multicaulis – Many-stemmed dudleya •
Dudleya nubigena – Cape liveforever •
Dudleya nesiotica – Santa Cruz Island liveforever •
Dudleya pachyphytum – Cedros Island dudleya •
Dudleya palmeri – Palmer's liveforever •
Dudleya parva – Conejo dudleya •
Dudleya pauciflora– Few-flower liveforever •
Dudleya pulverulenta – Chalk lettuce, chalk dudleya, chalk liveforever •
Dudleya rigida – Sierra de la Laguna liveforever •
Dudleya rigidiflora – Playa Maria liveforever •
Dudleya rubens – Red flowering liveforever •
Dudleya saxosa – Panamint liveforever •
Dudleya saxosa subsp. collomiae – Gila County liveforever •
Dudleya saxosa subsp. aloides – Desert liveforever •
Dudleya saxosa subsp. saxosa – Panamint liveforever •
Dudleya stolonifera – Laguna Beach liveforever •
Dudleya traskiae – Santa Barbara Island liveforever •
Dudleya variegata – Variegated liveforever •
Dudleya verityi – Verity's liveforever •
Dudleya virens – Alabaster plant, Island liveforever •
Dudleya viridicata – Colonet liveforever •
Dudleya viridis •
Dudleya viscida – Sticky dudleya
Etymology The genus is named after
William Russel Dudley, the first head of the botany department at
Stanford University. The name of the subgenera
Stylophyllum is an
allusion to the pencil-shaped leaves of the type species,
Stylophyllum edule, now known as
Dudleya edulis.'' •
Tiipai:
milhka’mey (wide-leaf);
milh kajmila (narrow-leaf) •
Paipai:
awi mielh == Reproductive biology ==