SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55dd26b961c0697066d95ad710736bb30d133130f76430fba3824146d829d227' 
  AND token = 'WBwlVzCRK+uqUjOCpooZcCCfwXT1hI83gRCtmzgvxUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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