Cinq espèces nouvelles de Marantaceae endémiques du Gabon.

Cinq espèces nouvelles de Marantacées d’Afrique sont décrites et illustrées de deux sites du Gabon, Marantochloa alba A. C. Ley, sp. nov., M. grandiflora A. C. Ley, sp. nov., M. montsdecristalii A. C. Ley, sp. nov. et Thaumatococcus flavus A. C. Ley, sp. nov. de la région montagneuse de Monts de Cristal, au nord-est de la capital Libreville, ainsi que Hypselodelphys lopei A. C. Ley, sp. nov., de la forêt secondaire près de La Lope et Mikongo, au centre du Gabon. De nouvelles clefs des genres Marantochloa Brongn. & Gris., Thaumatococcus Benth. et Hypselodelphys (K. Schum.) Milne.-Redh. sont fournies.Five new species of African Marantaceae are described and illustrated from two locations in Gabon, Marantochloa alba A. C. Ley, sp. nov., M. grandiflora A. C. Ley, sp. nov., M. montsdecristalii A. C. Ley, sp. nov. and Thaumatococcus flavus A. C. Ley, sp. nov. from the mountainous area of Monts de Cristal, north east of the capital Libreville, as well as Hypselodelphys lopei A. C. Ley, sp. nov. from the central part of Gabon in secondary forest near La Lope and Mikongo. New keys to the genera Marantochloa Brongn. & Gris., Thaumatococcus Benth. and Hypselodelphys (K. Schum.) Milne.-Redh. are provided

The Search for Common Origin: Homology Revisited

Understanding the evolution of biodiversity on Earth is a central aim in biology. Currently, various disciplines of science contribute to unravel evolution at all levels of life, from individual organisms to species and higher ranks, using different approaches and specific terminologies. The search for common origin, traditionally called homology, is a connecting paradigm of all studies related to evolution. However, it is not always sufficiently taken into account that defining homology depends on the hierarchical level studied (organism, population, and species), which can cause confusion. Therefore, we propose a framework to define homologies making use of existing terms, which refer to homology in different fields, but restricting them to an unambiguous meaning and a particular hierarchical level. We propose to use the overarching term "homology" only when "morphological homology," "vertical gene transfer," and "phylogenetic homology" are confirmed. Consequently, neither phylogenetic nor morphological homology is equal to homology. This article is intended for readers with different research backgrounds. We challenge their traditional approaches, inviting them to consider the proposed framework and offering them a new perspective for their own research.status: publishe

FLIES AS POLLINATORS OF MELITTOPHILOUS SALVIA SPECIES (LAMIACEAE)

Premise of the study: Floral adaptation to a functional pollinator group does not necessarily mean close specialization to a few pollinator species. For the more than 950 species of Salvia, only bee and bird pollinations are known. Restriction to these pollinators is mainly due to the specific flower construction (lever mechanism). Nevertheless, it has been repeatedly suggested that Salvia flowers might also be pollinated by flies. Are flies able to handle the lever mechanism? Are they functionally equivalent pollinators? In this study, we compared and quantified pollen transfer by bees and flies to test whether flies are true pollinators in Salvia

Pollination Ecology, Specialization, and Genetic Isolation in Sympatric Bee-PollinatedSalvia(Lamiaceae)

Premise of research. Previous pollination ecology studies ofSalviahave shown that there is low specialization for certain subgroups of bees and that pollinator number varies with species and locality. We studied 12Salviaspecies (three clades with different corolla morphologies and staminal lever mechanisms) that in part co-occur and coflower to examine prezygotic isolation mechanisms and the degree of specialization versus generalization in pollination ecology. Methodology. Pollinators were identified using field observations, photos, and related literature across three sites in Turkey. Video documentation of the visitation rate and the site of pollen placement on the pollinator body, morphometric measurements between flowers and pollinators, flowering time, flower color, handling time, and stigma contact ratio were analyzed. Plant-pollinator networks were constructed. Pivotal results. Mechanical, phenological, and ethological isolation occurs among sympatricSalviaspecies. A morphological fit is evident between flower tube length and the proboscis length of the main pollinators. Pollinator networks indicate that most species are ecological generalists and that only a few are specialists. Conclusions. The 12Salviaspecies, though phenotypically and functionally specialized by their zygomorphic, bilabiate flowers and bee-pollination syndrome, differ in the degree of their ecological specialization. Most of the sympatricSalviaspecies tend to be ecologically generalized, with two or more main pollinators and a few additional secondary pollinators, while a fewSalviaspecies are clearly specialized. Some floral traits (e.g., flower color, morphology, size, corolla tube length and width of the corolla tube entrance, type and size of the staminal lever mechanism, small numbers of flowers in the inflorescence), a short flowering time, and a small population size appear to be correlated with the degree of ecological specialization