SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a958343f75bc1c19a9691eb05889be33c82ce1b6fc7c0821305ebb1ff3ea209' 
  AND token = 'gsr1C7barmyurpNH3zLbV/0HrBN8Yv4UssgnJjHheTw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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