|
Nolaneae-Solanaceae
Phylogenetic Systematics of Nolana (Solanaceae) and Biogeographic Implications for the Atacama and Peruvian DesertsNational Science Foundation DEB - 0415573
Michael O. Dillon
|
 - Click for enlargement. - |
The vegetation of coastal Peru and northern Chile, termed "lomas" formations, is composed of floristic elements from a variety of biogeographic sources. The genus Nolana (Solanaceae-Nolaneae), with over 85 species, stands out as the most wide-ranging and conspicuous floristic element of these formations; and the evolutionary history of Nolana holds clues to age and origin of the coastal deserts. One endemic species is disjunct on the Galápagos Islands. Members of the Nolana have traditionally been recognized at the familial (Nolanaceae) or subfamilial (Nolanoideae) rank in the Solanaceae due to their unusual gynoecium of mericarps, however, results from molecular systematics have placed Nolana L. firmly within the family Solanaceae with closest relationships to Sclerophylax Miers, Phrodus Miers, Lycium L. and Grabowskia Schldl. in a clade that also contains Hyoscyamus L. and Atropa L. Studies of the relationships within the Nolana include data from extensive field studies, hybridization experiments, morphology, physiology, and molecular systematic investigations. The establishment of a phylogeny for Nolana provides a framework for testing hypotheses of character evolution and biogeography. |
|
The genus Nolana L.f. (Solanaceae) was originally described by Linnaeus in 1762 and derives its origin from the Latin, nola or small bell. The genus currently consists of 89 species from Peru (40 species) and Chile (44 species), four species found in both Chile and Peru, and one endemic species from the Galápagos Islands (Dillon, in press; Dillon, et al. 2003). Nolana is considered monophyletic and is diagnosed by possessing fruits of a 5-carpeled gynoecium forming sclerified mericarps with 1-7 seeds each, a unique derived character in the Solanaceae (Knapp, 2002). Most species (~70 species) occupy fog-dependent, coastal environments called lomas formations and occur from 8° to 30° S latitude and generally within 25 kms of the Pacific Ocean (Dillon, 1997; Dillon & Hoffmann, 1997; Rundel et al. 1991). The genus generally has flowers borne singly in the leaf axils and corollas small to large, tubular-salverform to campanulate, infundibular, or rotate, showy flowers. Colors generally range from blue to lavender with whitish to yellowish throats, with or without dark purple proximal spot and occasionally dark feathered nectar guides. As interpreted here, the genus Nolana contains 89 species, making it the 4th largest genus in the family Solanaceae, behind Solanum (1000-1500 spp), Lycianthes (ca. 200 spp), Cestrum (ca. 175 spp) and just slightly larger than Nicotiana (75-80 spp) and Physalis (60-70 spp). The number of species has been controversal with some workers only accepting 18 species. However, extensive observations throughout the range of the genus has allowed for the recognition of species primarily collected in poorly collected regions and during optimal conditions.
Phylogeny of Nolana (Solanaceae) PrePrint copy: Molecular Phylogeny and Evolution 49: 561-573. 2008.
Phylogeny of Nolana (Nolaneae, Solanoideae, Solanaceae) as
Click on the Nolana corolla button to access links:  Nolana
galapagensis was collected in the Galápagos Islands
on an expedition by Michael Dillon (15 February - 1 March 2004). Three
islands were visited and outgroup species, Grabowskia and Lycium
were also sampled. This is a collaborative study in conjunction with the
Charles Darwin Research Station and Dr. Alan Tye, the head of systematic
botany at CDRS.
[
Environments/Coastal Deserts] [Plant
Families] [Lomas
Floristic Database Activities] [Nolana
Evolution & Biogeography [Spanish]] [J.
Francis Macbride & Flora of Peru Series] |
