Abstract:

Objective: The genus Acantholyda Costa (Hymenoptera: Pamphiliidae) exhibits high species diversity in China, but the western regions remain insufficient investigation in terms of faunal composition and forest pest status. No species of this genus have previously been reported from Sichuan Province. This study reports and describes new species of Acantholyda collected from forest areas in Sichuan, providing scientific data for the integrated management of forest pests. Method: A classical comparative morphological approach was used to determine the taxonomic position and species identity of the specimens. Diagnostic features were examined and compared with those of closely related species to determine the main distinguishing characters. Result: Four new species of Acantholyda were identified and described: Acantholyda dolichogena Wei, sp. nov., A. fulvostigma Wei, sp. nov., A. kangi Wei, sp. nov., and A. pilosisoma Wei, sp. nov. Detailed morphological descriptions and illustrations of key diagnostic characters were provided for each species. This paper preliminarily discussed the distribution, origin, and evolution of the genus Acantholyda. It was found that species of Acantholyda distributed in East Asia and China had the highest diversity worldwide, accounting for approximately 50% and 29.4% of the known species, respectively. The middle and northern regions of East Asia are the main areas of distribution and diversification of this genus, and are presumed to be the origin center of this genus. Conclusion: The comparative morphological study has confirmed that the four Acantholyda species discovered in the forest areas of Sichuan are new species. This study enriches the understanding of Acantholyda species diversity and provides a scientific basis for biodiversity conservation and forest pest management in China.

Key words: Pamphiliomorpha, Cephalciinae, new species, plants of Pinaceae, specific diversity