Thilachium madagascariense (Capparaceae), a new species from eastern Madagascar with a key to the species of the genus

Thilachium madagascariense Fici, a small tree characterised by 1-foliolate leaves with articulate petioles, leaf blades elliptic or narrowly obovate with base attenuate and apex acuminate, flowers in groups of 2 – 3 at the top of lateral twigs and a high number of stamens, is described and illustrated from forest habitats of eastern Madagascar. The new species is similar to T. laurifolium Baker, a species endemic to central and eastern Madagascar, differing in the longer leaves with acuminate apex, flowers conferted at the top of lateral twigs, shorter pedicels, higher number of stamens and shorter gynophore. Its affinities are discussed and an updated key is provided for all the species of the genus Thilachium

A new species of Thilachium (Capparaceae) from the Analanjirofo Region, Madagascar

Madagascar is a centre of speciation for the genus Thilachium Lour., which includes several species of small trees and shrubs occurring in a wide range of habitats. A new species of Thilachium, T. latifolium Fici, from the Analanjirofo Region of northeastern Madagascar is here described and illustrated. It is characterised by 1-foliolate leaves, leaf blades widely ovate or elliptic with shortly acuminate or acute apices, flowers in terminal, dense subumbels or corymbs, short pedicels and ellipsoid, ribbed fruit. The new species is related to T. madagascariense Fici, a species recently described from eastern Madagascar, differing in the wider, coriaceous leaves with shorter, mucronulate tip, flowers in terminal, 7–16-flowered subumbels or corymbs, shorter pedicels and longer anthers. The distribution, autecology and affinities of the new species are discussed, its conservation status is assessed, and an updated key is provided for the species of the genus Thilachium known from Madagascar

A taxonomic revision of the Capparis spinosa group (Capparaceae) from the Mediterranean to Central Asia

A revision of the Capparis spinosa group has been carried out in southern Europe, northern Africa, western and central Asia, in order to provide a uniform taxonomic treatment of its representatives. The xerotropical origin of this group, showing disjunct distribution in several holoarctic and paleotropical regions, is underlined and the different species concepts historically adopted are discussed. In the present treatment a single species is recognized, C. spinosa, represented in the study area by two subspecies. C. spinosa subsp. spinosa shows derived characters, high polymorphism and a wide distribution range from the Mediterranean eastwards to China and Nepal. C. spinosa subsp. rupestris, less variable and showing phenotypic characters closer to the tropical stock of the group, is recorded in the Mediterranean Region and the Sahara. On the basis of herbarium and field investigations, the variability and distribution of the two subspecies are examined. Within each subspecies some varieties are recognized, for which morphological, chorological and autecological data are presented. Four new combinations (C. spinosa subsp. spinosa var. herbacea, C. spinosa subsp. spinosa var. atlantica, C. spinosa subsp. rupestris var. ovata, C. spinosa subsp. rupestris var. myrtifolia) are proposed

Evidences of adaptive traits to rocky substrates undermine paradigm of habitat preference of the Mediterranean seagrass Posidonia oceanica

Posidonia oceanica meadows are acknowledged as one of the most valuable ecosystems of the Mediterranean Sea. P. oceanica has been historically described as a species typically growing on mobile substrates whose development requires precursor communities. Here we document for the first time the extensive presence of sticky hairs covering P. oceanica seedling roots. Adhesive root hairs allow the seedlings to firmly anchor to rocky substrates with anchorage strength values up to 5.23 N, regardless of the presence of algal cover and to colonise bare rock without the need for precursor assemblages to facilitate settlement. Adhesive root hairs are a morphological trait common on plants living on rocks in high-energy habitats, such as the riverweed Podostemaceae and the seagrass Phyllospadix scouleri. The presence of adhesive root hairs in P. oceanica juveniles suggests a preference of this species for hard substrates. Such an daptation leads to hypothesize a new microsite driven bottleneck in P. oceanica seedling survival linked to substrate features. The mechanism described can favour plant establishment on rocky substrates, in contrast with traditional paradigms. This feature may have strongly influenced P. oceanica pattern of colonisation through sexual propagules in both the past and present

Genetic differentiation of the Capparis spinosa group in the Mediterranean area

The Capparis spinosa group is represented in the Mediterranean by a complex of taxa widespread in North Africa, the Middle East, and southern Europe. The taxonomy of this group used to be based on morphological characters with little work on the genetics of the group, and there is still much to be learned about its evolutionary history and diversification. We sampled 431 individuals of two subspecies and five varieties of C. spinosa and analysed them using highly informative EST-SSR markers to evaluate the population genetic diversity, structure and differentiation of the species in the Mediterranean. In addition, comparisons with the genetic profiles of C. spinosa subsp. cartilaginea, the putative ancestral taxon were made to investigate the phylogeographic history and possible gene flow across taxa. Integrated Bayesian approaches showed: i) a high divergence among C. spinosa subsp. spinosa var. canescens, C. spinosa subsp. spinosa var. aegyptia and the three varieties belonging to C. spinosa subsp. rupestris (var. rupestris, var. ovata and var. myrtifolia), with a clear separation between var. aegyptia and var. canescens which allows to consider var. aegyptia as a subspecies of C. spinosa; ii) a significant correlation between genetic divergence and geographic distance between the five varieties studied; iii) that the different varieties in the Mediterranean may have been derived from C. spinosa subsp. cartilaginea. Further genomic investigations are required to confirm our results. However, the findings presented allows us to suggest the genus Capparis can be considered a model for the study of the gene flow and differentiation in species occurring in a wide range of habitats

Narrow genetic base in forest restoration with holm oak (Quercus ilex L.) in Sicily

In order to empirically assess the effect of actual seed sampling strategy on genetic diversity of holm oak (Quercus ilex) forestations in Sicily, we have analysed the genetic composition of two seedling lots (nursery stock and plantation) and their known natural seed origin stand by means of six nuclear microsatellite loci. Significant reduction in genetic diversity and significant difference in genetic composition of the seedling lots compared to the seed origin stand were detected. The female and the total effective number of parents were quantified by means of maternity assignment of seedlings and temporal changes in allele frequencies. Extremely low effective maternity numbers were estimated (Nfe $\approx$ 2-4) and estimates accounting for both seed and pollen donors gave also low values (Ne $\approx$ 35-50). These values can be explained by an inappropriate forestry seed harvest strategy limited to a small number of spatially close trees

A new species of Capparis (Capparaceae) from ultramafic substrata in New Caledonia

A new species of Capparis, C. parvifolia, is described and illustrated from New Caledonia, where it is known from a few localities on Mont Kaala on ultramafic substrata. The new species is characterized by the relatively small, linear leaf-blade and by the small size of the sepals, petals, stamens, gynophore and fruit. Its affinities with related taxa are discussed and its conservation status assessed

Capparis irenae Fici 2021, sp. nov.

Capparis irenae Fici, sp. nov. (Fig. 1) A C. diffusa Ridl. ramunculis glabris, petiolis atque foliis longioribus, inflorescentia racemosa cum cataphyllis basalibus, petalis longioribus extus pubescentibus, staminibus longioribus praecipue differt. TYPUS. — Indonesia. Sumatra, Tigapulu [Tigapuluh] Mts, Riau Province, 5 km W of Talanglakat on Rengat-Jambi Road, Bukit Karampal area, G. Lolongan Kayu ridge, 7.XII.1988, Burley et al. 1946 (holo-, L1851428!). EPONYMIA. — Filia mea dilecta haec species dicata est. PHENOLOGY. — Flowering in December (based on available material). DISTRIBUTION AND ECOLOGY. — The new species is only known from the type locality in the Tigapuluh Mts of central Sumatra (Fig. 2), at 0°46’S, 102°32’E, where it was observed and collected in forest communities with Drepananthus biovulatus (Boerl.) Survesw. & R.M.K. Saunders (Annonaceae), Aphanamixis polystachya (Wall.) R.Parker (Meliaceae), Antidesma neurocarpum Miq. (Phyllanthaceae), Haemocharis integerrima Koord. & Valeton (Theaceae), Dillenia beccariana Martelli (Dilleniaceae), Celtis sp. (Ulmaceae), Lithocarpus sp. (Fagaceae), Pinanga sp. (Arecaceae), etc.; 300-550 m a.s.l. CONSERVATION STATUS. — Following the IUCN Red List Categories and Criteria (IUCN 2012), the new species is Data Deficient (DD) lacking information to make an assessment of its risks based on the population status. The area where the new species has been collected is close to the Bukit Tigapuluh National Park, including lowland and highland forests and refuge of several endangered mammal and bird species; this area, established as a national park in 1995, has been under relevant threat due to illegal logging and palm oil plantations. DESCRIPTION Climber up to 3 m long.Stem c. 1 cm diameter; twigs glabrous. Stipules Stipular thorns recurved c. 1 mm long, with blackish tip. Leaves Petioles sulcate, 5-7 mm long, glabrous. Leaf blades elliptical or narrowly ovate, wider below or at the middle, (2.3-) 2.5- 2.8 (-3.4) times as long as wide, (9-) 10.2-12.4 × (3-) 3.3-4.5 (-4.8) cm; base rounded or blunt; apex acute, acuminate with tip 5-10 mm long; surfaces glabrous; veins c. 5-8 on each side of the midrib, thin, decurrent along the margin. Flowers Flowers in axillary, few-flowered racemes with slender, glabrous axis c. 4.5-5.5 cm long, and few cataphylls at the base; pedicels 2.1-2.2 cm long, glabrous; bracts at the base of the flowers subulate, c. 0.3 mm long. Sepals green, acute, 3-3.8 × 1.5-2 mm, glabrous, ciliate at margins, inner pair with cartilaginous margin. Petals white, linear-oblong, c. 7 × (2.5-) 3-4 mm, pubescent at margins and outside, glabrous inside, the upper pair pale purple at margins near the apex. Stamens c. 14-16; filaments white, 2-2.5 cm long; anthers basifixed, bluish, c. 0.75 mm long. Gynophore c. 1.5 cm long, glabrous; ovary ovoid or subglobose, c. 1 × 0.75 mm, glabrous, with pointed stigma. Fruit Unknown. REMARKS Capparis irenae, sp. nov. belongs to C. sect. Monostichocalyx, which includes about 18 species in Indonesia (Jacobs 1960, 1965; Fici 2012). The new species is a climber, mainly distinguished from related taxa by its glabrous twigs, short stipular thorns, leaf blades elliptical or narrowly ovate, flowers arranged in axillary racemes with cataphylls at the base, sepals small and glabrous, ciliate at margins, petals pubescent outside and ovary glabrous, small, with pointed stigma. C. irenae, sp. nov. shows affinities with C. diffusa Ridl., a shrub or climber recorded from Cambodia, Thailand, Malaysia and northern Sumatra, which however differs (Appendix 1) in the twigs puberulous when young, petioles 2-4 mm long, leaves up to 8.5 cm long, flowers in terminal or lateral sessile umbels, petals hairy inside, c. 4-6 mm long, and stamens with filaments c. 1.25 cm long (Jacobs 1960, 1965). C. irenae, sp. nov. is also related with other species characterized by innovations with cataphylls (small subulate bract-like scales) at the base, included by Jacobs (1965) in the Cataphyllosa-Group. Among these C. fusifera Dunn, a species from India (southern part of the Deccan Peninsula), differs in the twigs densely brown-puberulous, inflorescence a small axillary axis 0.5-1 cm long, pedicels 6-16 mm long, stamens c. 56 and ovary spindle-shaped c. 1.5 × 1 mm, whereas C. pubiflora DC., widespread in south-eastern Asia, Philippines and Indonesia, can be easily distinguished by the young twigs densely covered with balance-hairs, sepals 4-7 mm long, stamens 20-30 (-50), gynophore densely tomentose and ovary densely tomentose, 2.5 mm long (Jacobs 1965) (Appendix 1). The type material of the new species belongs to rich collections carried out by Burley et al. on November-December 1988 in the Tigapuluh Mts., Riau Province of central Sumatra (Burley 1988). Herbarium collections constitute a fundamental source of data in such poorly explored areas, for which floristic knowledge is so far scanty or lacking.Published as part of Fici, Silvio, 2021, A new species of Capparis L. (Capparaceae) from Sumatra (Indonesia), pp. 61-66 in Adansonia (3) (3) 43 (7) on pages 62-64, DOI: 10.5252/adansonia2021v43a7, http://zenodo.org/record/466570