Stingless bees (Hymenoptera: Apidae) in Holocene copal and Defaunation resin from Eastern Africa indicate Recent biodiversity change

Abstract

Although specimens in fossil to Recent resins are remarkable for their fidelity of preservation, amber is well known and studied, unlike the younger resins as Pleistocene copal (2.58–0.0117 Ma) and Holocene copal (0.0117 Ma–1760 AD), or Defaunation resin, which is resin produced after 1760 AD. However, the scientific relevance of these younger resins preserving arthropods that lived in pre-Anthropocene time is often underestimated. Here, we present specimens of workers of stingless bees included in copal and Defaunation resin, from the coastal vichaka forests in Tanzania, and from northwest Madagascar, ranging in age from almost 3000 BP years to only 80 ± 30 BP years and from 2015, respectively. Three known species Hypotrigona gribodoi, Liotrigona bouyssoui, and Liotrigona nilssoni and two new species Axestotrigona kitingae sp. nov. and Hypotrigona kleineri sp. nov. have been discovered from 36 studied specimens. We also noted that the holotype of Trigona richardsi is a junior subjective synonym of Axestotrigona ferruginea ferruginea. The coastal forests in the East Africa region and in East Madagascar are now highly fragmented so that we can expect that the new species are already extinct. Here we demonstrate that the study of inclusions in copal and Defaunation resin can document losses of local biodiversity resulting, for example, from deforestation and they also bring proof of this potential anthropic defaunation.