SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7f80e6b485fdffbeadbcd4cb77db08b599918912658d6c57a2155782fcb13cd' 
  AND token = 'DkGIiFgP3+0FqihFN69/6WfvwcMKpKu+dJhZpmo8u+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}