And Yet They Differ: Reconsiderations of Diversity within Dactylochelifer latreillii (Arachnida: Pseudoscorpiones)

Abstract

Morphological stasis is a widespread characteristic of pseudoscorpions, suggesting that much cryptic diversity remains unexplored. Here, we revise the polytypic species Dactylochelifer latreillii in the framework of an integrative taxonomic approach, using DNA barcoding, multivariate ratio analysis, geometric morphometry of the male foretarsus, and genitalic morphology. The pattern of mitochondrial variation suggests three species-level entities in central Europe, which widely overlap in morphospace, but differentiate in the structure of the female genitalia, and by their ecology. Dactylochelifer latreillii (Leach) is a halobiont species, occurring exclusively in coastal habitats and in Pannonian salt steppes, and D. l. septentrionalis Beier syn. nov. is a junior synonym of the nominate species. Dactylochelifer degeerii (C. L. Koch) stat. rev. is the oldest available name for an inland species that has long been mistaken for the nominotypical subspecies of D. latreillii. New habitat information suggests a preference for higher shrub vegetation. Dactylochelifer ninnii (Canestrinii) stat. rev. is a halophilic Mediterranean species that extends to the northern limits of the Pannonian basin. The distinctiveness of the Mediterranean "form" was recognized by early naturalists in the 19th century, but was ignored by later authorities in the field.