SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65b37d589e19857db1db0487a95df3d2cfa394f1ae86ab05d94f5fdb6c3c6a19' 
  AND token = 'CSHb5/kXAlngdKgIcN/zd64tT/W7gwZGjq1BPya9RQY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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