SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10ff284d7c9921f48e5a8ff50ed2983ccb5749f0efb08bce93083aa0ab8314c6' 
  AND token = 'ETg4qQ/KUUlG09+xV6QcYRzFEC8SbzIigBMvVHHu718=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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