SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3024e926b98831fe33dc8b3fd0a0667625a764dec9bc28db8d87b4ca3cb7d388' 
  AND token = 'OJcHtpsuKQC28fHoSOna7xthOSvcf/G9UTQIojdj9Kg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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