Dasykothon leptomiscus gen. et sp. nov., a fossil flower of possible Lauralean affinity from Myanmar amber
DOI:
https://doi.org/10.17348/jbrit.v14.i1.897Resumen
Se describe un nuevo fósil de angiosperma, Dasykothon leptomiscus, de depósitos de ámbar del Cretácico medio en el valle de Hukawng del noroeste de Myanmar (Birmania). La flor está en post-antesis excepto por un estambre que retiene su polen. El perianto es ligeramente irregular y está compuesto de 5 sépalos ovados o linear-lanceolados, erectos o incurvados. Los ca. 12 estambres tienen filamentos delgados y anteras dorsifijas, con dos tecas, dehiscentes longitudinalmente. El ovario súpero lleva 2 estilos largos y curvados. Los granos de polen germinados en los estigmas son monoporados y tienen la característica peculiar de una cresta surcada que circunda el grano de polo a polo. Se hipotetiza que esta estructura sea un cambio evolutivo del surco sincolpado meridionalmente que se encuentra en algunos miembros de las Atherospermataceae. La morfología floral generalizada del fósil impide una asignación a una familia moderna.
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