Polycarpon

Abstract: Dalgaard, V.: Chromosome numbers in flowering plants from Madeira. - Willdenowia 16: 221-240. 1986. - ISSN 0511-9618. 125 chromosome numbers are reported for 99 species of flowering plants from Madeira. 23 numbers are new or deviate from previous reports. Chromosome numbers of 40 taxa are reported for the first time from Macaronesia, those of another 17 taxa for the first time from Madeira. Taxonomic and phytogeographical comments are provided for some species. The new or deviating counts occur within the following genera: Aichryson, Anthyllis, Cardiospermum, Carlina, Erysimum, Festuca, Galium, Genista, Hypericum, Isoplexis, Laurus, Matthiola, Melica, Oenanthe, Pericallis, Polycarpon, Polygonum, Rumex, Solanum, Sonchus, Teucrium, Viola.

Abstract: The chromosome number and known karyological features (karyotype description, presence of secondary constrictions, presence of accessory chromosomes, karyotype asymmetry) are reviewed for the sexually-reproducing endemic flora of the Balearic Islands (100 taxa), a continental archipelago in the Mediterranean. Chromosome numbers range from 2n = 8 (Crepis triasii) to 2n = 94 (Helictotrichon crassifolium), with 2n = 30 as the modal value. Overall, the number of inferred diploid taxa (57) predominates over polyploid ones (42). Intraspecific karyological variation accounts for about 10% of the whole endemic flora and includes within-individual poly-morphisms related to (1) euploid changes involving somatic segregation or endopolyploidy, (2) the presence of supernumerary (B) chromosomes, and (3) karyological variation in species showing holocentric chromosomes. True infraspecific cytological variation involving fixed euploid changes has been verified only in a single taxon, Ranunculus paludosus subsp. barceloi. Overall, the documented patterns of infraspecific karyological variation in the endemic Balearic flora are of limited evolutionary potential since (1) fixed number of accessory chromosomes within individuals has not been detected in any endemic species so far analyzed, and (2) the two ploidal cytotypes of Ranunculus paludosus subsp. barceloi are geographically structured (Eastern vs. Western Balearics), precluding the formation of hybrid zones. The available data (singularity of chromosome numbers and ploidy levels, as well as biosystematic and molecular evidence) strongly suggest that at least nine polyploid endemic species (Agrostis barceloi, Allium antonii-bolosii, Anthyllis hyxtrix, Brassica balearica, Bupleurum barceloi, Centaurium bianoris, Coronilla montserratii, Helictotrichon crassifolium, Polycarpon colomense) could have had autochthonous origins in the Balearic archipelago from diploid or low polyploid-level ancestors. This hypothesized polyploid element accounts for at least 26.2% of the endemic polyploid flora and contrasts with the low estimates of polyploid evolution reported from oceanic archipelagos.

Abstract: Recent published molecular analyses have shown that the genus Polycarpon is polyphyletic and includes only the members belonging to the Polycarpon tetraphyllum aggregate. Morphologically, dehiscence of the capsule by valves that elastically roll inwards and eject the seeds provides a clear synapomorphy for Polycarpon in this restricted sense. Among the excluded taxa, the South American P. anomalum , P. suffruticosum and P. coquimbense are not described taxonomically, although molecular and morphological evidence exists. We here propose to recognise these species as a new South American endemic genus ( Augustea gen. nov. ) with three recognized species. The names Polycarpon suffruticosum (var. suffruticosum , and var. virens ), P. australe , and P. anomalum are lectotypified. A diagnostic key is provided, as well as descriptions, ecological information and distribution for each species.

Abstract: Background. Caryophyllaceae is a large and cosmopolitic flowering plant family, however the systematics of many of its basal groups has been unclear, due to a lack of unambiguous morphology. Some members of Caryophyllaceae are used medicinally, e.g. Corrigiola roots in Morocco. Monitoring the trade in medicinal plants is complicated due to the absence of useful identification characters in plant products such as roots, bark, and powders.This thesis aims at elucidating the systematics and the ethnobotany of some of the basal clades in Caryophyllaceae. Methods. A comprehensive sampling from herbarium as well as market and field collected material was used in systematic studies combining morphological investigation, molecular phylogenetic and molecular dating analyses. Results. The data show that Polycarpon is polyphyletic, that Sphaerocoma is sister to Pollichia and shows some intraspecific variation, that Sanctambrosia falls within the genus Spergularia, and that both Spergula and Spergularia are monophyletic. Preliminary data suggest that Polycarpaea is polyphyletic and should be split into three larger and several smaller genera, that the members of Paronychia subgen. Anaplonychia will need to be transferred to Herniaria to maintain monophyly, and that Caryophyllaceae emerged during the Paleocene. All the major extant lineages originated in the Oligocene and diversified later. Using molecular identification it was possible to identify around 50% of the Moroccan medicinal roots to species level and an additional 30% to genus level. Discussion and conclusions. The polyphyletic Polycarpon needs to be split into at least three separate genera, but no name changes were made pending further research. The two species of Sphaerocoma were merged into one species with two subspecies. The San Ambrosio Island endemic Sanctambrosia, the only tree-like plant in Caryophyllaceae, is probably the result of a long distance dispersal event and its woody habit and gynodioecy are probably caused by inbreeding depression. Sanctambrosia manicata is transferred to Spergularia. Molecular identification put into practice on traded medicinal roots has a somewhat lower success rate than most theoretical studies, indicating that a global barcoding database would need to include reference sequences from a broad range of populations for each species.