SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d70845cebe1600b305d41067c806cadd3ac8d710c20f8aa50a650a2719b1092' 
  AND token = 'f3TpyPgJgjQ8S5mvPngVxrD++mvLXxBf8PifNVpCuT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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