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Seed reproduction is considered a critical bottleneck of the plant life cycle, constraining population growth, especially in the Mediterranean area. In this study, we investigated seed reproduction of Lamyropsis microcephala (Asteraceae), a threatened species occurring only in the Gennargentu massif (CE Sardinia, Italy). Seed output was quantified in two of the four localities where the species occurs, which differed in population size. Germination of seeds from all the four localities was assessed, both in the field and under controlled conditions, and the annual trend of soil temperature recorded by data-loggers. Plants had ca. 60 cypselas (i.e. the fruits of Asteraceae) per capitulum in the larger Rio Aratu and ca. 30 in the smaller Pisargiu locality, with only ca. 1.7 and 0.3 germinating cypselas per capitulum, respectively. Under controlled conditions, seeds of the two large localities (Bau ‘e Laccos and Rio Aratu) germinated above 80%, while those of the two small ones (Bruncu Spina and Pis...

The aims of this work were to verify the distribution and population size of Lamyropsis microcephala (Asteraceae), characterize its habitat, assess its conservation status and initiate conservation measures for this Critically Endangered species. Distribution was determined by field surveys and mapping. To estimate population size and density 81 permanent monitoring plots were randomly established. Ex situ conservation measures were activated by harvesting and appropriate storage of seed. We confirmed the presence of L. microcephala at two previously known sites and found it in two previously unknown localities. The areas in which the species occur vary from 200 to 240,000 m2, at altitudes of 1,450–1,820 m, on slopes of 15–45° with aspects from north to west. The estimated number of ramets per population varied from c. 2,000 to c. 2,000,000, with a mean density of 8.29 ± SD 14.3 to 10.33 ± SD 10.05 ramets m-2. Our findings confirmed the Critically Endangered status of this species, although with different criteria. This study is an example of an integrated approach for the conservation of an extremely narrow endemic plant species and may be useful for other little-known threatened species for which urgent conservation measures are needed.

Lamyropsis microcephala only occurs in a very restricted area in the Gennargentu massif (CE-Sardinia, Italy) at 1450-1700 m a.s.l. This rare species has been inserted in the International Union for Conservation of Nature (IUCN) Red Lists under Critically Endangered. In this study, the effect of a pre-chilling period (90 days at 5°C) on germination was investigated as well as the ability of this species to form a soil seed bank. L. microcephala seeds exhibited type 2 non-deep physiological dormancy. Pre-chilling increased the final germination percentages, the germination speed and the temperature range at which high levels of germination were observed. The high optimal germination temperatures (ca. 70% germination at 30°C) demonstrate that this species is well adapted to a temperate climate and the lack of a persistent soil seed bank represents a rarity trait that likely exacerbates the threats to the survival of this species.

The aim of this study was to give results about position of Lamyropsis microcephala within an already existing phylogeny of Lamyropsis genus on the Mediterranean area, by analyzing external transcribed spacer/internal transcribed spacer sequence data. The four Lamyropsis species considered in the model can be recognized as distinct taxa originated from successive migration/speciation events.

Endangered species with small and isolated populations has been a key topic of conservation biology studies in the last decade. Lamyropsis microcephala is among the most significant narrow endemic plants in the Mediterranean region, lying on the Gennargentu massif of the Sardinia island (Italy). Due to heavy threat factors, this species has rapidly become threatened with extinction. The inter-simple sequence repeat technique was used to assess the genetic variation and structure of the individuals growing in the four remnant localities known to date, with the aim to implement further conservation strategies. Results indicated a degree of differentiation among the four subpopulations, in particular for the Fonni one. The estimates of Nei's genetic diversity (H) ranged from 0.0563 (Fonni) and 0.1104 (Bau 'e Laccos). Analysis of molecular variance values showed that 53% of the total variation may be attributed to the individuals within subpopulations, while 47% is due to differences among subpopulations (P < 0.001). Results also highlighted a scarce gene flow (Nm = 0.503). © 2013 Societá Botanica Italiana.