bat
蝙 centers on the animal bat, specifically the small flying mammal. It is rarely used alone and typically appears in the compound 蝙蝠 (こうもり).
蝙 combines 虫 (insect/creature) with 扁, which likely contributes the sound ヘン. The character classifies the bat as a small winged creature.
The insect radical 虫 on the left suggests a small creature, and the right side 扁 looks like a flat, spread-out shape. Picture a bat with its wings spread flat like the 扁 shape, a creature that looks like a flying insect.
For ヘン, imagine a hen chasing a bat out of the barn: hen -> ヘン, and the bat flutters away.
bat (Chiroptera spp.)
fraternal myotis (Myotis frater); long-tailed whiskered bat
Indian flying fox (Pteropus giganteus); greater Indian fruit bat
Kitti's hog-nosed bat (Craseonycteris thonglongyai); bumblebee bat; Old World hog-nosed bat
Shinano whiskered bat (Myotis ikonnikovi hosonoi); Hosono's myotis
brown long-eared bat (Plecotus auritus); common long-eared bat; brown big-eared bat
Daito flying fox (Pteropus dasymallus daitoensis)
fruit bat (Pteropodidae spp.); flying fox; megabat
tube-nosed fruit bat (Nyctimeninae spp., esp. the common tube-nosed fruit bat, Nyctimene albiventer)
Hilgendorf's tube-nosed bat (Murina hilgendorfi)
Japanese house bat (Pipistrellus abramus)
Ussuri tube-nosed bat (Murina ussuriensis)
Japanese noctule (Nyctalus furvus)
Bonin flying fox (Pteropus pselaphon); Bonin fruit bat
Bonin flying fox (Pteropus pselaphon)
little Japanese horseshoe bat (Rhinolophus cornutus); Japanese lesser horseshoe bat
birdlike noctule (Nyctalus aviator)
Asian particolored bat (Vespertilio sinensis)
northern Ryukyu fruit bat (Pteropus dasymallus dasymallus)
Okinawa flying fox (Pteropus loochoensis)