We studied anatomical and functional aspects of the reproductive system of females of the Magdalena river stingray Potamotrygon magdalenae using microscopic and macroscopic analysis of each organ. Although the reproductive tract was fully functional on both side, the left organs possibly have a greater contribution to reproductive success, because left ovary and uterus were more developed and had higher number of oocytes and embryos, respectively, than the right ones. This species has histotrophic viviparity given by the presence of uterine trophonemata and by glandular character in pregnant and postpartum females. We suggest that the epigonal organ is involved in the degradation of components of atretic follicles and the embryos begin to develop surrounded by a gelatinous tertiary envelope produced by the oviducal gland. This latter organ is composed by three zones in mature females, club, papillary, and baffle zone, as described for other elasmobranchs. From the anatomical observations, a maturity scale comprising six sexual maturity stages (Immature I, Immature II, early mature, pregnant, post-partum, and regenerating) was established for female P. magdalenae, and it can be useful as basis for reproductive studies of other potamotrygonid species. Finally, we propose a continuous reproductive cycle for P. magdalenae.

Morphology, anatomy, ontogeny and chemical composition of inflorescences volatile secondary metabolites of Lippia alba (Verbenaceae) at three stages of development. There is an increased interest to know and scientifically validate traditional knowledge of medicinal plants. Lippia alba belongs to Verbenaceae family and has been of interest, not only because of its worldwide extensive distribution, but also for its variable use as antiviral, bactericide, citostatic, analgesic and sedative. To study this, the morphology and ontogeny of Lippia alba inflorescences and the chemical composition of its volatile secondary metabolites were analyzed during three different stages of development. Plants were collected at the experimental crop field in CENIVAM, Bucaramanga, Colombia. The inflorescence's morphology and ontogeny, and the chemical composition of volatile secondary metabolites were analyzed using a stereoscopic microscope and chromatographic and spectroscopic techniques. Fresh material corresponding to each stage was fixed in F.A.A (formol, acetic acid and alcohol), included in paraffin and cutted in transversal and longitudinal sections. Sections were stained with safranine-fastgreen, photographed and decribed. The chemical composition of volatile secondary metabolites at each ontogenic stage, was extracted by solid phase micro-extraction in the headspace mode and analyzed by gas chromatography coupled to mass spectrometry. Stage I showed a meristematic mass of cells in vegetative apex and bracts, with an outline of floral whorls. In Stage III, the stamens were adnate, epipetals and didynamous, bicarpelar and syncarpic gynoecium, with superior ovary and decurrent stigma. The main secondary metabolites detected were the bicyclosesquiphellandrene followed by carvone, limonene and trans-β-farnesene, that constituted the 78% of the total relative amounts of compounds. Other metabolites such as β-copaene, γ-amorphene and cis-β-guaiene, were reported for the first time in this study. When compared to other studies, morphological differences reported in this study are possibly related to adaptation to environmental conditions or pollinators, which let us suggest that there is no specific ontogenic pattern. Similarly, the qualitative and quantitative variations in the detected compounds could be explained because one or more of them are used as precursors of others.