SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5191434affcff8a82b45135ca1afc1ee2079364d5626dc3332b387d891fa8f96' 
  AND token = '3KoTsX3veyNfbD5zInmpccC0dY+gDSecuW4d4oUXDfw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables