Peripatric speciation in an endemic Macaronesian plant after recent divergence from a widespread relative.

The Macaronesian Scrophularia lowei is hypothesized to have arisen from the widespread S. arguta on the basis of several phylogenetic studies of the genus, but sampling has been limited. Although these two annual species are morphologically distinct, the origin of S.

Scrophularia arguta, a widespread annual plant in the Canary Islands: a single recent colonization event or a more complex phylogeographic pattern?

Many studies have addressed evolution and phylogeography of plant taxa in oceanic islands, but have primarily focused on endemics because of the assumption that in widespread taxa the absence of morphological differentiation between island and mainland populations is due to recent colonization. In this paper, we studied the phylogeography of Scrophularia arguta, a widespread annual species, in an attempt to determine the number and spatiotemporal origins of dispersal events to Canary Islands. Four different regions, ITS and ETS from nDNA and psbA-trnH and psbJ-petA from cpDNA, were used to date divergence events within S.

Evolution of the staminode in a representative sample of Scrophularia and its role as nectar safeguard in three widespread species.

Approximately 30% of the genera of Scrophulariaceae s.str. have a staminode, which is the remnant of a sterile stamen.

The role of birds and insects in pollination shifts of Scrophularia (Scrophulariaceae).

The mixed vertebrate-insect pollination system is rare in Holarctic plants. Phylogenetic relationships of 116 Scrophularia taxa were investigated based on two plastid (ndhF and trnL-trnF) and one nuclear (ITS) DNA regions. A wider time-calibrated analysis of ndhF sequences of the Lamiales revealed that Scrophularia diverged as early as in the Miocene (<22 Ma).

Insects, birds and lizards as pollinators of the largest-flowered Scrophularia of Europe and Macaronesia.

Background And Aims: It has traditionally been considered that the flowers of Scrophularia are mainly pollinated by wasps. We studied the pollination system of four species which stand out for their large and showy flowers: S. sambucifolia and S.

Self-sterility in two Cytisus species (Leguminosae, Papilionoideae) due to early-acting inbreeding depression.

In most angiosperms, the endosperm develops before the embryo, but with harmony between the two structures until final seed formation. In an embryological study, we show that inbreeding depression causes disharmony in development of the two structures in two Leguminosae shrubs, Cytisus multiflorus and C. striatus.

Pollen-stigma interference in two gynodioecious species of Lamiaceae with intermediate individuals.

Background And Aims: Intermediate individuals (perfect flowers with very high degree of pollen abortion) in a gynodioecious plant species are very rare. A study is made of male-female relationships in each flower type and how floral characters can enhance the avoidance of 'pollen discounting' and 'self-pollination' in two gynodioecious species, Teucrium capitatum and Origanum syriacum.

Methods: The relationship between stigma receptivity and pollen viability was studied in two gynodioecious protandrous species of Lamiaceae, in addition to measuring some floral morphological characters over the life span of the flowers.

Megasporogenesis, megagametogenesis and ontogeny of the aril in Cytisus striatus and C. multiflorus (Leguminosae: Papilionoideae).

Background And Aims: There are few embryological reports on wild legumes and even fewer on their seminal appendages. There are no existing studies on the complete ontogeny of these appendages in Cytiseae, a very important Papilionoideae tribe in Mediterranean ecosystems. In this work megasporogenesis, megagametogenesis and aril ontogeny were studied in Cytisus multiflorus and C.