SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd05811656f3c878919af213007fd10df18b971cf84c6f002810f2a2fd49bd0bb' 
  AND token = 'Dd8unWZxYBDO7yGuq+eprEzXOysS+/Mx1ehjk8Zyzt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}