Anatomy, Morphology, and Cladistic Analysis of Monsonia L. (Geraniaceae).

Abstract

Se exploran mediante un an41isis cladfstico las relaciones filogen&icas entre las 25 especies incluidas en el genero Monsonia. Tras una detallada revisi6n se seleccionan 20 caracteres raorfoldgicos y anatomicos, entre ellos algunos previamente no descritos sobre los nectarios, el androceo y los mericarpos. El anSlisis filogen&ico produjo nueve arboles mas parsimoniosos. El arbol de consenso estricto muestra dos clados principales: uno, formado por las nueve especies de Monsonia sect. Monsonia, caracterizadas por las aristas plumosas y las tres de Sarcocaulon que se usaron como grupo externo; y el segundo, fonnado por las 16 especies de Monsonia sect. Olopetalum, que comparten el tipo de separaci6n del mericarpo, la consistencia de la columela y las paredes gruesas en el mericarpo. Como consecuencia surgen nuevas dudas sobre la monofilia de Monsonia. Sin embargo, nuestros datos apoyan la clasificacion subgene'rica actual de Monsonia si se incluyen M. tongipes y M. speciosa en la sect. Olopetalum. Numerosos caracteres del mericarpo estan relacionados con el tipo de zoocoria, lo cual parece derivado en Monsonia al igual que en otras geraniaceas.Palabras clave: anatomi'a, morfologia, anSlisis cladistico, Monsonia, Geraniaceae. Phylogenetip relationships among the 25 species of the old-world genus Monsonia are explored by means of a cladistic analysis. After a detailed revision, 20 morphological and anatomical characters were selected, including some new ones from nectaries, androecium, and mericarps. Phylogenetic analysis yielded 9 most parsimonious trees. The strict consensus tree showed two major clades: one is formed by the 9 species of Monsonia sect. Monsonia, characterised by plumose awns, plus Sarcocaulon; and a second with the 16 species of Monsonia sect. Olopetalum which share the type of mericarp detaching, consistency of columella and the thick mericarp walls. Consequently, some doubts about the monophyly of Monsonia exists. However, the current infrageneric classification of Monsonia is supported after transferring M. longipes and M. speciosa to sect. Olopetalum. Several characters of the mericarp are related to zoochory, which seems to be a derived syndrome in Monsonia, as in the other Geraniaceae.

The phylogeny of Monsonia L. (Geraniaceae)

“…Although a cladistic analysis of morphological characters lead Aldaroso et al (2001) to the conclusion that the Sarcocaulon species belong to the genus Monsonia, they still treated these species as a separate genus. They also found, that based on morphological characters, Sarcocaulon is monophyletic and share the following synapomorphies: Succulent stems covered by wax and spines formed from petioles.…”

“…Monsonia has been shown to display a remarkably broad range of morphological variation (Venter 1979, Aldaroso et al 2001. The inflorescence consists of either a large single flower or several small flowers arranged into cymes.…”

“…Sweet (1820), Boissier (1867), Harvey and Sonder (1894), Reiche (1896), Knuth (1912), Kers (1968), Venter (1979Venter ( , 1990, Moffett (1979Moffett ( , 1997, Verhoeven and Venter (1986) and Dreyer et al (1997) contributed to a better understanding of Monsonia and Sarcocaulon and proposed taxonomic classifications of the genus. Aldaroso et al (2001) proposed the most recent infrageneric classification of Monsonia s. str. based on 20 morphological and anatomical characters.…”

L'étude caryologique de deux cultivars de Violettes odorantes remet en cause leur origine taxonomique

“…odorata L. Clausen (1926Clausen ( , 1927Clausen ( , 1931, Miyaji (1929Miyaji ( , 1930, Madge ( 1929), Gershoy (1932Gershoy ( , 1934, Tischler ( 1934 ), Theron (1939), Delay (1948), Gadella ( 1963 ), Gadella & Kliphuis (1963 ), Sharma ( 1970), Vachova ( 1976), Verlaque et al ( 1987), Galland ( 1988), Tiniakou ( 1991Tiniakou ( , 1992, A1dasoro (1992), Druskovic & Lovka (1995) Schmidt ( 1961 ) Lippert (1977), Galland (1988), Nikolov ( 1991 ), Tiniakou ( 1991Tiniakou ( , 1992, Aldasoro ( 1992) Schmidt ( (Schmidt, 1961 ), contrairement a V 'Tourrettes sur Loup'. Par consequent, l'origine du V 'Tourrettes sur Loup' doit se trouver dans V suavis qui est, par ailleurs, une espece assez commune des Alpes-Maritimes.…”

California, a new genus of Geraniaceae endemic to the southwest of North America

“…The other Geraniaceae genera {Monsonia and Sarcocaulon) have a whorl of 15 stamens fused in the base (monadelphous) or fused in five groups of three (pentadelphous), whereas Pelargonium has 2-7 monadelphous stamens. An exception is also found in Monsonia brevirostrata Knuth, which has only five fertile stamens (ALDASORO & al., 2001). The androecium structure of Erodium could be related to that of Geranium due to a likely substitution of a whorl of fertile stamens by staminodes.…”