C. Edward Freeman

Patterns in floral nectar characteristics of some bird-visited plant species from Costa Rica

Nectar samples from a wide range of flowers (120 samples, 112 species, 22 families) visited by hummingbirds (subfamilies Phaethorninae and Trochilinae) were collected over a wide range of elevations and environments in Costa Rica. Some species visited are believed to be pollinated principally by perching birds, lepidopterans, and bees, however. We measured sugar composition (% fructose, glucose, and sucrose), daily secretion rates, and sugar concentration. In general, sugar compositions of all hummingbird nectars were found to be highly clustered toward the high-sucrose end of the composition spectrum and not significantly different from sugar compositions of other hummingbird nectar assemblages from northwestern Mexico and the southwestern United States. Significant correlations were detected between elevation and the percentage of fructose and of sucrose in the nectar, with the fructose percent positive and the sucrose negative. These correlations were found to be due to both elevation and hummingbirdgroup effects. Daily secretion rate and sugar concentration were both negatively correlated with elevation. Discriminant analysis indicated that nectar sugar concentration and daily secretion rates together could usually predict whether a species was pollinated by hermit (Phaethorninae) or nonhermit (Trochilinae) hummingbirds and could often predict which eco-morphological group of nonhermits.

Floral nectar sugar compositions of some south and Southeast Asian species

Floral nectars of 62 species native to south and southeast Asia were sampled opportunistically, mostly in Malaysia, and analyzed for sugar composition by HPLC. The sugar compositions of these nectars have not been previously reported in the literature. The distribution of the nectars in terms of percentage sucrose tended to be one of two extremes: either high sucrose or low sucrose. Principal pollinators of only a few of these species have been hypothesized in the literature. Most of these had nectar sugar compositions consistent with the principal pollinators posited. A few did not. Sugar compositions of Old World bat-pollinated species were typically found to be much richer in sucrose than those of New World bat flowers and to vary considerably. Possible reasons for these observations are discussed. PLANT SPECIES POLLINATED BY animals have flowers that attract and reward these animals for their visitation. Suites of floral characteristics (e.g., color, size, morphology, and odor) are associated with

Inferred Phylogeny in Keckiella (Scrophulariaceae) based on Noncoding Chloroplast and nuclear ribosomal DNA Sequences

Abstract Two non-coding DNA regions from both the chloroplast genome (trnL intron, trnL–trnF IGS, trnT–trnL IGS) and nuclear ribosomal genomes (ITS1 and ITS2) were sequenced in the genus Keckiella and allied genera (Penstemon, Chelone, and Nothochelone) to determine which, if any, of these sequences contained sufficient variability to resolve the seven species of Keckiella. The trnL intron contained almost no signal. However, the trnT–trnL chloroplast IGS region and the nuclear ribosomal sequences were capable, to some extent, of resolving the phylogeny of Keckiella. The nrDNA ITS sequences contained slightly more variability than the chloroplast noncoding region. When combined, these non-coding sequences generated a relatively robust and resolved cladogram. Keckiella rothrockii is clearly indicated as the most basal species of the genus, and the remaining taxa appear to belong to two well-supported clades. The first contains the sister taxa K. antirrhinoides and K. cordifolia. The second contains K. breviflora, K. ternata, K. corymbosa, and K. lemmonii. The nodes of the latter three species are not as strongly supported.