SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a5de1f17289b8d175a8bd811dd5c44e65de34b84e9317c3bb0bd8d7ddf33f52d' 
  AND token = '4UVtMU/hpwyW8x53ErAanjFcWuTZwDmJgnGZ/xhQuoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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