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The subtribe Pyrinae, formerly the Maloideae, is a monophyletic group of about 1,000 species that includes well known fruit crops such as apple (Malus), pear (Pyrus), quince (Cydonia), loquat (Eriobotrya), chokeberry (Aronia), and serviceberry (Amelanchier). Generic limits have been fluid in Pyrinae, especially in Malus, Sorbus and Photinia. This study evaluated the generic limits of 180 samples of multiple species or accessions from each of the traditional genera using sequences of the nrDNA ITS region. The ITS data recognized 24 genera, including Amelanchier, Aria (including Micromeles), Aronia, Chaenomeles, Chamaemespilus, Chamaemeles, Cormus, Cotoneaster, Crataegus, Cydonia, Dichotomanthes, Eriobotrya, Hesperomeles, Malacomeles, Malus (including Chloromeles, Docynia, Docyniopsis, and Eriolobus), Mespilus, Osteomeles, Peraphyllum, Pourthiaea, Pseudocydonia, Pyrus, Rhaphiolepis, Sorbus, and Torminalis. However, both Photinia and Pyracantha are polyphyletic. Photinia is separated into different clades, one of which contains species of Heteromeles and Stranvaesia. Asian species of Pyracantha do not form a clade with P. coccinea of southern Europe and Iran. Our results support the close relationship of Amelanchier, Malacomeles, and Peraphyllum, and of Crataegus and Mespilus, and for the first time recognize the sister relationship of the South American genus Hesperomeles with the Crataegus-Mespilus clade. [ABSTRACT FROM AUTHOR]

In amphibians, theory predicts that male mate choice with respect to female body size can be expected to occur when female fecundity is related to body size and when the time and energy invested into one mating are relatively large. Based on experimental observations, we tested whether male mate choice occurs in a population of the Andrew’s toad ( Bufo andrewsi), a species in which both assumptions are likely to be met. When a male B. andrewsi was placed with a gravid female and a non-gravid similar-sized female, the male did not discriminate between them. When two gravid females with distinct size differences were provided to a male, the male preferred the larger one. In an experiment in which two different-sized gravid females were put in two separate transparent cylinders to exclude potential chemical cues, males spent more time in proximity to the larger gravid females and jumped more frequently towards the larger gravid females than the smaller ones. These findings suggest that male B. andrewsi recognizes female body size, exhibits mate choice, and prefers to mate with larger females that provide greater reproductive potential. [ABSTRACT FROM AUTHOR]