Reported Distribution, Species Richness, and Sampling Bias of Culicoides (Diptera: Ceratopogonidae) in Türkiye: A Literature-Based Synthesis with a Biogeographical Framework

Culicoides biting midges are important veterinary vectors, yet reported distributional patterns in Türkiye may reflect both ecological structure and uneven sampling. We synthesized 58 eligible Türkiye-specific reports (50 database-derived and eight citation-traced), consolidated them into 43 study/data-source families, and compiled 1164 taxon records representing 62 taxa. The all-explicit province dataset included 33 provinces and 45 taxa, whereas the primary province dataset included 18 provinces and 43 taxa. National taxonomic sources supported 72 species within the eligible evidence chain and 74 under a later taxonomic interpretation. Reported richness was strongly associated with sampling effort (Poisson coefficient = 0.579, 95% CI: 0.385–0.773), whereas biogeographical region was not significant after effort was accounted for (likelihood-ratio p = 0.914). Jaccard PERMANOVA identified an exploratory regional compositional pattern (F = 4.388, R2 = 0.369, p = 0.001; PERMDISP p = 0.325), with turnover accounting for approximately 78% of mean between-region dissimilarity. Most richness diagnostics ranged from 54 to 64 taxa, whereas Chao2 was unstable (69.6; 95% CI: 49.5–152.0). Vector-related evidence remained insufficient for species–pathogen risk modeling. Overall, the synthesis is consistent with a Wallacean shortfall strongly associated with uneven sampling and supports standardized, biogeographically balanced surveillance to test transition-zone structure, climate-sensitive phenology and redistribution, and integrated vector-host-pathogen hypotheses under comparable sampling effort.