SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da415192a2128664ef1fc6bdb8cb195cd62a0d498bb3fc5fc25426647b2659e8' 
  AND token = 'ZeHD8s+RMHlUzHJZsQT5eaS3uG6oxIfxcUi84o1SD5M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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