Sistemática, biogeografia e distribuição potencial de Tetragona Lepeletier & Serville, 1828 (Hymenoptera: Apidae: Meliponini)

Abstract

Tetragona Lepeletier & Serville, is a genus with a primarily neotropical distribution, characterized by stingless bees presenting: an elongated metasoma, long and slender mesotibial spur, metatibia with a slender basal portion and a rounded posterior border, with intermixing simple setae and branched hairs on posterior border, velvety genal area, propodeal triangle entirely glabrous, and yellow pigmented maculation on body (i.e., clypeus, paraocular area, mesonotum, scutellum, and posterior borders of the terga). The species of this genus occur from Uruguay to north or Neotropical region. The genus has a strong phylogenetic connection with Ptillotrigona Moure and Camargoia Moure, as they share some synapomorphies such as the sixth sternum of the male with a long, narrow and cylindrical median process and the seventh sternum narrow, long and forming the antecostum in a “Y” shape. With the obtaining of specimens (and photos), in dry form, from various national and foreign collections, a taxonomic review was proposed, as well as a phylogenetic and biogeographic analysis of all species of the genus, thus resulting in a total of twenty species valid: with three recently published species (T. atahualpa Nogueira & Rasmussen, 2020, T. mourei Nogueira, 2022, T. korotaii Nogueira, 2022) and six new (T. fumosa sp. nov., T. flava sp. nov., T. cachoeira sp. nov., T. francocamargoi sp. nov., T. maracaensis sp. nov. and T. angulata sp. nov.) and the synonyms of T. elongata and T. dissecta with T. clavipes and T. mayarum with T. ziegleri. A worker identification key, a diagnosis for the species groups, a diagnosis for the species already described and the description of males and queens, when possible, were proposed. Each species had its geographic records updated, as well as a compilation of data on nesting biology and behavior. The phylogenetic analysis recovered the genus as monophyletic, with relationships not yet established with Ptilotrigona and Camargoia. Almost all proposed species groups were recovered in the phylogeny, except the truncata group, which had T. truncata as a sister group of T. maracaensis sp. nov.+T. kaieteurensis, leaving T. atahualpa without well-established relationships. The biogeographic analysis recovered two major speciation events, separating the dorsalis group from the rest and then the clade that gave rise to the handlirschii, truncata and kaieteurensis groups of the clade that gave rise to the clavipes, goettei and essequiboensis groups. Despite efforts to understand the phylogenetic and biogeographic relationships of the genus, molecular analyzes or other tools that help taxonomy can help to elucidate aspects of the relationship with other closely related genera, as well as the internal relationships between groups and species.