Floral Biology of Rhipsalis paradoxa (Cactaceae: Cactoideae) in Atlantic Mesóflia Semidecidua, Serra do Japi, Jundiai–SP

Abstract

The aim of this study was to investigate the floral biology and to determine the main floral visitors and potential pollinators of R. paradoxa (Cactaceae). This study was conducted in an Environmental Protection Area in the Serra do Japi, Jundiaí-SP. The R. paradoxa flowering season comprehended the months of September and October of 2001. The principal floral visitors were Apis melifera, B. brasiliensis, Melipona quadrifasciata, Melipona bicolor and Trigona sp., all these bees belonging to Apidae family, thus this species consists in a melittophilous cactus. All floral visitors are potential pollinators. B. brasiliensis was considered the main pollinator, since it is a very common species, displays legitimate visits and promotes xenogamy when they move between distant individuals in the population. A. mellifera, M. bicolor and M. quadrifasciata are secondary pollinators, presenting lower visitation rates and short distance flights, promoting mainly self-pollinations and low gene flow within the population of R. paradoxa. Trigona sp. was the most common species and remained longer time in the flowers, however, this bee visited essentially flowers within the same plant favoring basically the geitonogamy, for this reason was considered only as a secondary pollinator. The conservation of the main pollinators of R. paradoxa is crucial for conservation of this cactus species that depend exclusively on bee pollination for its reproductive success.

Pollen‐feeding bees in Uebelmannia pectinifera subsp. pectinifera – reproductive biology of an endemic cactus from the campo rupestre of eastern Brazil

“…An insight to the cactus reproductive mechanisms is the first step towards understanding genetic structure and demographic dynamics (Pereira et al 2009) of plant species. Only 10% of the 270 Brazilian cacti have been studied from the floral and reproductive biology (Schlindwein and Wittmann 1995, Aona et al 2006, Colaço et al 2006, Lenzi and Orth 2011, Rego et al 2012, Gomes et al 2014, Martins et al 2016, Paulino‐Neto et al 2016, Martins and Freitas 2018, Rocha et al 2019). Teixeira et al (2018) inferred that Uebelmannia buiningii may be Critically Endangered (CR) because of a combination of pressure on its habitat and illegal collection negatively impacting its already small populations, added to gametophyte self‐incompatibility that leads to obligate allogamy, dependent on pollinators in order to produce seeds.…”