Estudo taxonômico do gênero Aechmea Ruiz & Pav. (BROMELIOIDEAE, BROMELIACEAE) no estado da Paraíba, Brasil, e fenologia reprodutiva de A. leptantha (HARMS) Leme & J.A. Siqueira-Filho

Abstract

Aechmea Ruiz & Pav. (Bromeliaceae) gathers more than 250 species, consisting of the most numerous genus of the subfamily Bromelioideae. Due to its wide morphological variation, it presents a very complex and controversial taxonomic delimitation. Phenological studies, fundamental for floral biology and conservation, are also relatively incipient in the genus. In the present work the taxonomic study of Aechmea for Paraíba (Northeast of Brazil) and the phenological strategies of Aechmea leptantha (Harms) Leme & J.A. Siqueira-Filho were carried out. This species is endemic to the Northeast of Brazil and restricted to a remnant of Atlantic Forest of the State, being included in the list of species of Bromeliaceae Endangered species. The taxonomic study was based on field work carried out in municipalities in Paraíba and on the analysis of exsicatas deposited in national herbariums and queries to the database Specieslink. The phenological study was based on biweekly 'in loco' observations made during 12 months for the recording of reproductive phenophases. The phenological data were correlated with abiotic factors (temperature, humidity and rainfall). Eleven species were recognized in the studied area: Aechmea aquilega (Salisb.) Griseb., A. chrysocoma Baker, A. costantinii (Mez) LB Sm., A. emmerichiae Leme, A. eurycorymbus Harms, A. fulgens Brongn, A. leptantha (Harms) Leme & JA Siqueira-Filho, A. mertensii (G. Mey.) Schult. & Schult. F., A. nudicaulis (L.) Griseb., A. patenstisima (Mart. Ex Schult. F.) Baker and A. werdermannii Harms. Of these, seven are endemic to Northeast Brazil and eight were included in one of the three threat categories (five "Vulnerable", two "In Peril" and one Critically In Peril "), besides one considered as "Almost Threatened" and two as "Little Worrying". Descriptions, identification keys and illustrations of the diagnostic characters of the species were produced. Flowering, fruiting, distribution, environments and conservation status of the species are presented. Aechmea leptantha presented a flowering pattern of the cornucopia type, making available resources of the species of the genus, To the pollinators for about ten weeks and strongly seasonal, beginning in the dry period.The flowering was positively correlated with the temperature and the fruiting with the rainfall and humidity. The population presented synchrony in the flowering.The fruiting took place throughout the year, With zoocoric fruits being dispersed throughout the study period, suggesting that A. leptantha is an important resource for the fauna of the region.