Andrena (Aciandrena) Warncke 1968

Zenodo (CERN European Organization for Nuclear Research)

Abstract

SubgenusAciandrenaWarncke, 1968 Genetics. The Subgenus Aciandrena is taxonomically complex, and difficult to characterise both morphologically and genetically using barcodes. Some taxa placed in the subgenus such as Andrena janthina Warncke, 1975 (see Gusenleitner and Schwarz 2002) actually represent undescribed subgenera (Pisanty et al. 2022 a, 2022 b), and are not considered here, as all constituent species are Levantine (S. Bossert, G. Pisanty, T. J. Wood, unpublished data). Even in a narrow sense, Aciandrena s. str. seems particularly prone to the generation of NUMTs (Nuclear Mitochondrial DNA sequences) based on results from nanopore sequencing which can produce multiple different sequences from the same individual (unpublished data). As such, individual unusual sequences must be treated with great care to avoid the overdescription of taxa, particularly since females are often impossible to separate with confidence morphologically. A particularly troublesome species pair are Andrena aciculata Morawitz, 1886 and Andrena lamiana Warncke, 1965. Males are separable after dissection and examination of the apex of sternum 8 (truncate in A. aciculata, narrowly pointed in A. lamiana, see male identification key), but females are much more challenging if not impossible to separate morphologically. Genetically, sequences of A. aciculata were available from Czechia, North Macedonia, and Greece (Samos, Rhodes), and sequences of A. lamiana were available from Greece (East Macedonia; Fig. 1). Andrena aciculata showed moderate intraspecific variation of 3.37 % (range 0.45–6.28 %) but formed a ladder of sequences towards A. lamiana. The two A. lamiana sequences were identical, and were separated from A. aciculata by an average genetic distance of 3.76 % (range 0.86–5.05 %). Resolution of these two taxa remains obscure, and it is very possible that many specimens are misidentified in the female sex. Identification continues to rely on dissection of males. Additional focused study of this subgenus using additional molecular tools including nuclear DNA is necessary to resolve species boundaries across the East Mediterranean and Middle East.

Authors 1

1. Thomas James Wood corresponding Aachen Naturalis Biodiversity Center

   Naturalis Biodiversity Center

   Affiliation as printed

   Naturalis Biodiversity Center, Darwinweg 2, 2333 CR, Leiden, Netherlands