SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'deb2bbcf060ed0ae20386d7e140d4848dadc1b30d8eab0c3bdd197d1ddd89743' 
  AND token = 'fiXe3z+kx1ti/UoUwDG0CTjoQVzl5ggr6JSh0fyxp/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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