Taxonomy of the Proisotoma complex. VI. Rediscovery of the genus Bagnallella Salmon, 1951 and epitoky in Bagnallelladavidi (Barra, 2001), comb. nov. from South Africa.

Mikhail Potapov,Charlene Janion-Scheepers,Louis Deharveng

doi:10.3897/zookeys.1072.71307

Mikhail Potapov, Charlene Janion-Scheepers + Show 1 more

Open Access

https://doi.org/10.3897/zookeys.1072.71307

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Abstract

The genus Bagnallella Salmon is restored and given a diagnosis. It takes an intermediate position between Proisotoma Börner and Cryptopygus Willem complexes and is characterized by the separation of the two last abdominal segments (like in Proisotoma) and 3 and 5 s-chaetae on the fourth and fifth abdominal segments (like in Cryptopygus and its allies). A list of and key to species belonging to Bagnallella is given. Bagnallellabisetacomb. nov., B.dubiacomb. nov., B.sedecimoculatacomb. nov., and B.tenellacomb. nov. are commented and redescribed. Morphology of Bagnallelladavidi (Barra), comb. nov. is described from the specimens from South Africa. So far B.davidi appears to be a complex of forms differing in size of the furca and macrochaetae. Two types of strongly modified males were found and described. Antennae, ventral side of abdomen, posterior edge of abdominal tergites, and mandibles are affected with epitoky. The nature of the discovered strong polymorphism is unclear.

Highlights

Knowledge on the Collembola of South Africa has increased significantly over the last decade, with most new species described from the Western Cape Province where the majority sampling has been made (Janion-Scheepers et al 2015)
The species obviously belongs to the genus Bagnallella by separation of two last abdominal segments and s-chaetotaxy of Abd.IV and V
** At present Bagnallella biseta cannot be reliably discriminated from Proisotoma koepckei based on the existing descriptions

Summary

Introduction

Knowledge on the Collembola of South Africa has increased significantly over the last decade, with most new species described from the Western Cape Province where the majority sampling has been made (Janion-Scheepers et al 2015). From these collections, a rich diversity of Isotomidae has been discovered, including Parisotoma (Potapov et al 2011) and Cryptopygus (Potapov et al 2020). A rich diversity of Isotomidae has been discovered, including Parisotoma (Potapov et al 2011) and Cryptopygus (Potapov et al 2020) From these collections, we recorded three known species (P. davidi, P. tenella, P. sedecimoculata), which resemble the genus Cryptopygus but have Abd. V and VI separated. We describe an unusual polymorphism in Proisotoma davidi (Barra, 2001) which remains unsolved

Materials and methods

Discussion