The stingless bee Melipona beecheii is experiencing colony decline due to floral resource scarcity caused by deforestation. A study was conducted to identify the floral resources used by M. beecheii using honey samples collected in four regions of the state of Campeche, Mexico. A melissopalynological analysis of sixteen collected honey samples identified 69 plant species from 24 families, and established that Fabaceae was the main plant family visited. Based on botanical origin, seven samples were classified as monofloral and nine as multifloral. The predominant species were Bursera simaruba, Lonchocarpus longistylus, Piscidia piscipula, Senna pallida and Senna racemosa. Shannon diversity index values (2.06–2.55) indicated moderate diversity in floral resources and Simpson diversity index values (0.82–0.89) indicated a moderate dominance of plant species in the studied regions. The results suggest M. beecheii is polylectic with some degree of specialization. The plant species identified as predominant in the studied honey samples are candidates for use in strategies intended to conserve the food resources used by M. beecheii on the Yucatan Peninsula.

The palm honey (Sabal yapa C. Wright ex Becc.) (Sabal honey henceforth) is one of 22 unifloral honeys recognised in the Yucatan Peninsula. This honey is harvested in February and March when Sabal yapa bloom but encompasses other important melliferous plants during the harvest season. A melissopalynological study of 24 honey samples from Tizimín, Yucatan (Mexico) was used to determine if Sabal honey is monofloral or multifloral, and to investigate the pollen contribution of other plants. Consequently, we determined the plant resources foraged by Apis mellifera. After analysis, 54 different pollen types were identified with the number of pollen types per honey sample ranging between nine and 21, with a mean of 14.75. Asteraceae and Fabaceae were the most diverse families and represented the highest percentage of contribution in pollen spectra. Sabal yapa pollen had a mean content of 56.9% (with a range of 45.4% to 84%). Bursera simaruba, Haematoxylum campechianum, Piscidia piscipula and Viguiera dentata were categorised as secondary pollen. Important minor pollen corresponded to Caesalpinia gaumeri, Ceiba pentandra, Pisonia aculeata, Thouinia paucidentata, and Trixis inula. Pollen composition revealed details of not only the rich native flora that accompanies Sabal yapa, but traditional human activities that occur around the apiaries. As expected, pollen of nectariferous species predominate in the samples, but also a number of nectarless species were found. Honeybees foraged mostly in trees present in remnants of primary vegetation, or at its different succession stages. Sabal honey could be labelled as monofloral.

Melliferous plants are natural source of nectar and pollen for honeybees and their pollen grains are present in honey. The melissopalynological study of Sabal yapa honey produced in Yucatan has shown that eighteen species contribute importantly to its honey composition. We use melliferous plants associated with Sabal honey to test the potential of three barcodes (rbcL, ITS2, and trnH-psbA) in species identification to confirm the botanical origin and authentication of honey. Secondarily, we test the success rates of amplification and sequencing of each barcode. A total of 38 sequences were generated: 10 for rbcL, 13 for ITS2 and 15 for trnH-psbA. The success rate in PCR amplification was 94.73 % for trnH-psbA and 84.21 % for ITS2, while for rbcL was 52.63 %. Regarding sequencing success, 100 % of the products were amplified with rbcL. For trnH-psbA and ITS2, the sequencing success was 88.9 % and 87.5 %, respectively. ITS2 produced a species identification efficiency of 46.15 %, followed by rbcL (30 %). For trnH-psbA, the rate of species identification was 13.33 %. The sequences generated in this work will allow the construction of a reliable library of barcodes of melliferous plants, and with forward increasing will be possible to have a solid base for metabarcoding studies in the honey of the Yucatan Peninsula. Las plantas melíferas son fuente natural de néctar y polen para las abejas, por lo que sus granos de polen están presentes en la composición de la miel. El estudio melisopalinológico de la miel de Sabal yapa producida en Yucatán mostró que 18 especies contribuyen de manera importante en la composición de la miel. En este estudio utilizamos plantas melíferas asociadas a la miel de Sabal para evaluar el potencial de tres códigos de barras (rbcL, ITS2 y trnH-psbA) en la identificación de especies para confirmar el origen botánico y la autenticidad de la miel. También evaluamos el éxito de amplificación y secuenciación de cada código de barras. En total se generaron 38 secuencias: 10 para rbcL, 13 para ITS2 y 15 para trnH-psbA. El éxito de amplificación para los marcadores fue: trnH-psbA (94.73 %), ITS2 (84.21 %) y rbcL (52.63 %). El éxito de secuenciación para los marcadores fue: rbcL (100 %), trnH-psbA (88.9 %) e ITS2 (87.5 %). La eficiencia en la identificación de especies para ITS2 y rbcL fue de 46.15 % y 30 %, respectivamente. La eficiencia de trnH-psbA para identificar especies fue de 13.33 %. Las secuencias generadas en este trabajo permitirán la construcción una biblioteca de códigos de barras de plantas melíferas confiable y en la medida que se enriquezca, se podrá tener una base sólida para estudios de metabarcoding en la miel de la Península de Yucatán As plantas melíferas são fonte natural de néctar e pólen para as abelhas, e seus grãos de pólen estão presentes na composição do mel. O estudo melissopalinológico do mel de Sabal yapa produzida em Yucatan mostrou que 18 espécies contribuem de forma importante para a composição do mel. Usamos plantas melíferas associadas ao mel de Sabal para testar o potencial de três códigos de barras (rbcL, ITS2 e trnH-psbA) na identificação de espécies para confirmar a origem botânica e a autenticação do mel. Em segundo lugar, testamos as taxas de sucesso de amplificação e sequenciamento de cada código de barras. Foi generado um total de 38 sequências: 10 para rbcL, 13 para ITS2 e 15 para trnH-psbA. O sucesso da amplificação por PCR foi: trnH-psbA (94,73 %), ITS2 (84,21 %), rbcL (52,63 %). Com relação ao sucesso do sequenciamento, 100 % dos productos foram amplificados com rbcL (100 %). Para trnH-psbA e ITS2, o sucesso do sequenciamento foi de 88,9 % e 87,5 %, respectivamente. O ITS2 produziu uma eficiência de identificação de espécies de 46,15 % seguido por rbcL (30 %). A eficiência do trnH-psbA para identificar as espécies foi de 13.33 %. As sequências geradas neste trabalho permitirã construir uma biblioteca confiável de códigos de barras de plantas melíferas e, com o aumento futuro, será possível ter uma base sólida para estudos de metabarconding no mel da Península de Yucatán.

Hymenocallis ruenesiana is described and illustrated as a new species from the Yucatan Peninsula, Mexico. When comparing the morphological characters of the leaf, inflorescence, fruit and pollen, as well as the environmental conditions of the habitat of H. ruenesiana, discontinuities were found with those of Hymenocallis littoralis. Hymenocallis ruenesiana is endemic to the Yucatan peninsula, inhabiting seasonal savannas with clayey and floodable soils, while H. littoralis naturally inhabits the coasts, on easily drained sandy soils and it is also widely cultivated as an ornamental plant.