SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd22f6a56e6b0163a305183a5e941eff047268abf936a4cd4aacac7711fd51928' 
  AND token = 'milzyHBngtw1Btc2Fq9+H+IOSjeE85/3v3iZjiJivDA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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