This study documents the diversity of epiphytic lichens inhabiting crop trees in the lowlands of Pathanamthitta district, Kerala, India. A total of 32 lichen species were identified, with 12 crustose and 20 foliose forms. The family Caliciaceae was the most prevalent, with eight recorded species. Notably, foliose lichens exhibited reduced thallus size and smaller lobes compared to typical growth patterns. Parmotrema praesorediosum was the sole exception, displaying larger lobes than the other collected foliose specimens. The study identified Areca catechu and Cocos nucifera as the tree species supporting the highest lichen diversity. The findings are crucial for understanding lichen biodiversity in anthropogenically modified habitats and will establish a foundational baseline for conservation and ecological monitoring in the agro-forestry systems of the Western Ghats biodiversity hotspot.