Integrative Taxonomy and Climatic Niche of Oenothera laciniata Hill From Pakistan

ABSTRACT

Oenothera laciniata Hill (Onagraceae), cutleaf evening primrose, is a rarely reported species from Pakistan using integrative taxonomy. First field collections from Swabi revealed diagnostic characters including deeply lobed leaves, yellow ephemeral flowers, elongated floral tubes, and cylindrical capsules. Chloroplast rbcL sequences confirmed identity. Global records show a broad but discontinuous distribution across North America, Europe, and East Asia, with sparse occurrences in Africa, South America, Australia, and South Asia, including eight verified records from Pakistan. Climatic analyses showed a narrow temperature niche (mean 17.69°C ± 3.41 SD; range 3.08°C–26.20°C), with a strong latitudinal relationship ( R ²  = 0.133), while longitudinal influence was weak ( R ²  = 0.003). Hydroclimatic analyses revealed a broader precipitation niche (mean 735.84 mm ± 385.58 SD; range 149–2917 mm), with occurrences in semi‐arid to sub‐humid regions, avoiding extreme arid and hyper‐humid environments. Precipitation variation was governed by longitude (adjusted R ²  = 0.100). These findings suggest that although the species possesses high dispersal capacity, its realized distribution remains structured by temperature and precipitation constraints. This study expands Pakistan's floristic diversity, provides the confirmed record of O. laciniata from South Asia, and highlights the importance of combining taxonomy with DNA barcoding for documenting overlooked alien species.