SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '298ce2de5111ef4aeb6830149347e132201169e9b4480e8ef249b3d9d94b8b55' 
  AND token = 'pSdJrWdUR9pHMyHFwNRJ3t28yWcZUwmmt0Sq7vI2ZKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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