Discovery of a new black fly species in the Simulium (Simulium) striatum species-group (Diptera: Simuliidae) from Northeastern Thailand and its phylogenetic relationships with seven Thai related species

• Main Authors: Srisuka, Wichai, Takaoka, Hiroyuki, Aupalee, Kittipat, Saeung, Atiporn
• Format: Article
• Published: Elsevier 2023
• Subjects: R Medicine (General)
• Online Access: http://eprints.um.edu.my/38741/

The female, male, pupa and mature larva of Simulium (Simulium) poolpholi sp. nov. collected from a large and seasonal stream in northeastern Thailand are described. This new species is placed in the S. striatum species -group by the female sternite 8 concave posteromedially in form of the inverted-U shape, ovipositor valve with a ventrally produced process along its inner margin, male ventral plate saddle-shaped, style with a basal pro-tuberance, and pupal gill with 10 filaments. It is morphologically similar to S. (S.) phraense Takaoka, Srisuka & Saeung from northern Thailand by lacking annular ridges on the surface of pupal gill filaments but it is distin-guished from the latter species by the arrangement of pupal gill filaments. Molecular analysis using the fast-evolving nuclear big zinc finger (BZF) gene shows that S. (S.) poolpholi sp. nov. formed a distinct clade, being separated from the seven other Thai species of this species-group by a genetic distance of 1.84-4.55%. Our discovery increases the number of species in the S. striatum species-group in Thailand to nine.