SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fea7cf4a7dbe37b0ade258418adfea153cb36be877123bf127f85f782bb804f' 
  AND token = 'N1nnrAIyOLctS5JI2dY5OJgGBl5JmVUkWDteQuSICFM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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