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Extrafloral nectaries (EFNs) mediating ecologically important ant–plant protection mutualisms are especially common and unusually diverse in the Leguminosae. We present the first comprehensively curated list of legume genera with EFNs, detailing and illustrating their systematic and phylogenetic distributions, locations on the plant, morphology and anatomy, on the basis of a unified classification of EFN categories and a time-calibrated phylogeny, incorporating 710 of the 768 genera. This new synthesis, the first since Mckey (1989)'s seminal paper, increases the number of genera with EFNs to 153 (20% of legumes), distributed across subfamilies Cercidoideae (1), Detarioideae (19), Caesalpinioideae (87) and Papilionoideae (46). EFNs occur at nine locations, and are most prevalent on vegetative plant parts, especially leaves (74%) and inflorescence axes (26%). Four main categories (with eight subcategories) are recognised and include the following: formless, trichomatic (exposed, hollow), parenchymatic (embedded, pit, flat, elevated) and abscission zone EFNs (non-differentiated, swollen scars). Phylogenetic reconstruction of EFNs suggests independent evolutionary trajectories of different EFN types, with elevated EFNs restricted almost exclusively to Caesalpinioideae (where they underwent spectacular morphological disparification), flat EFNs in Detarioideae, swollen scar EFNs in Papilionoideae, and Cercidoideae is the only subfamily bearing intrastipular EFNs. We discuss the complex evolutionary history of EFNs and highlight future research directions. [ABSTRACT FROM AUTHOR]

The stereotyped floral morphology of Neotropical Malpighiaceae species—zygomorphic and calyx with oil glands—is correlated with oil-bee pollination. In contrast, the floral trends of the Paleotropical lineages are actinomorphy and lack of calyx glands, probably due to the absence of oil-collecting bees. The Paleotropical genus Acridocarpus is an exception because of its zygomorphic, gland-bearing flowers. Glands throughout Acridocarpus inflorescences were morphoanatomically evaluated to verify the occurrence of patterns related to species and geographic distribution. Herbarium (25 species) and fresh samples of A. longifolius were processed according to standard anatomical techniques. To verify the presence of glucose and protein, strip tests were applied to the exudate. Fresh samples were fixed and submitted to histochemical tests. Based on the occurrence, number and placement of glands, three distribution patterns were recognized on the bracteole and ten on the calyx. Bract, bracteole and sepal glands have a typical nectary structure with a palisade-like epidermis and vascularized parenchyma. Glands were classified as short-stalked, sessile or immersed. Histochemical tests performed on bract and sepal glands of A. longifolius were positive for proteins, polysaccharides and phenolic compounds, and negative for oil compounds. Glucose and protein were detected in the exudate. These results allow us to recognize the glands in Acridocarpus inflorescences as nectaries. This comprehensive morphoanatomical study helps to clarify the correlation between patterns of floral morphology and secretion consumers, as well as to better understand floral evolution in Malpighiaceae across their dispersal events. [ABSTRACT FROM AUTHOR]

Floral development and anatomy were investigated in the monotypic Aextoxicaceae (one species: Aextoxicon punctatum), one of two families of Berberidopsidales, to understand its putative relationship with Berberidopsidaceae and clarify floral evolution in basal core eudicots. Aextoxicon is dioecious, with unisexual flowers that display a late abortion of male and female organs in the respective genders. Flowers are pentamerous or hexamerous and are enclosed by a calyptra derived from the congenital fusion of two bracteoles. Initiation sequence and number of sepals, petals, and stamens are variable and mostly spiral, without clear transition between organ categories, and a single carpel initiates without evidence of a second carpel. The ovary contains two apical-marginal ovules. Floral anatomical data suggest that the nectaries are receptacular in nature. Aextoxicon displays floral characters found in basal angiosperms, such as a unicarpellate gynoecium, an interrupted hoodlike outer integument, little differentiation between sepals and petals, and a transition of a decussate to spiral phyllotaxis at the level of sepals. These data indicate that Aextoxicon, together with Berberidopsidaceae, might represent a basal transitional lineage of basal to core eudicots and evidence that pentamerous flowers with a biseriate perianth evolved from progenitors with a comparable floral structure. [ABSTRACT FROM AUTHOR]

Based on botanical specimens collected in the state of Jalisco, Mexico, Echeveria patriotica (Crassulaceae) is described and illustrated. Due to the possession of the following features, it is assigned to series Gibbiflorae (Baker) A. Berger: stem present, leaf blades narrowed at the base in the form of a pseudopetiole, inflorescence with more than 3 ramifications and an elongated rachis, and corolla cylindrical-urceolate more than 13 mm long. Of the species belonging to this section. E. patriotica is most similar to E. grisea E. Walther, from which it differs by having longer a pedicel, calyx and corolla. In addition, it is distinguished by the color of the flower and the nectaries. [ABSTRACT FROM AUTHOR]

The floral development and anatomy ofDirachmahas been investigated with SEM and LM to discuss the relationship of Dirachmaceae with putative sister taxa (e.g. Rhamnaceae, Malvaceae, Barbeyaceae, Elaeagnaceae) on the basis of morphological synapomorphies. Flowers are initiated in axillary position on terminal branches. An epicalyx consisting of six to eight bracteoles surrounds the valvate calyx. Petal initiation is strongly retarded and primordia arise independently opposite the stamen primordia. The carpels arise independently and become weakly fused at the base; a single ovule develops in an axile position. A hypanthium develops by interprimordial growth between petals and stamens. Nectaries arise in a pouch and are covered with trichomes positioned on a protuberance at the base of the petal. It is suggested that the solitary flowers are derived from compound cymose inflorescences. Comparison betweenDirachmaand species of Rhamnaceae demonstrates striking similarities in floral structure and anatomy. However, several characters are unique toDirachmaand support a family Dirachmaceae separate from Rhamnaceae. [ABSTRACT FROM AUTHOR]

Heterodichogamy is reported for the first time in the family Hernandiaceae (Laurales); furthermore, this heterodichogamy is of a novel type hitherto not reported in angiosperms. In Hernandia nymphaeifolia, which has unisexual flowers and is monoecious, two kinds of individuals were found: one kind with exclusively female flowers open in the morning and male flowers open in the afternoon and the other kind with the reverse behavior. The flowers are arranged in compound thyrses with cymes of two male and one female flower. Developmental studies confirm an earlier interpretation of these triads as monochasia with the sequence male- male-female. Surprisingly, though, the sequence is reversed at anthesis: most triads flower with the sequence male-female-male. Flower development shows that the gynoecium is unicarpellate (and not pseudomonomerous). In male flowers there are three rudimentary mounds (as yet overlooked) alternating with the stamens, which may correspond to those mounds in the female flowers that are united into a ring-shaped nectary and may represent extremely reduced staminodes. As heterodichogamy is an apparently rare phenomenon in angiosperms, it is of interest that heterodichogamy, although of a different type, has long been known in some Lauraceae, the sister family of Hernandiaceae. For an evolutionary understanding, the flowering behavior of the other genera of Hernandiaceae should be studied. [ABSTRACT FROM AUTHOR]

Functional Ecology (2004) 18, 125–129 [ABSTRACT FROM AUTHOR]

Studies foraging by two species of territorial male hummingbirds at clumps of scarlet gilia, Ipomopsis aggregata, inflorescences. Evidence of area-restricted search with differential response to low and high rewards encountered during a foraging bout at plants that have accumulated the most nectar per flower; Study methods and results; Studies of foraging in patchy environments; Remembrance of the quality of locations from earlier bouts or responding to the current path rewards.