SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a8b224769538fe32d392657779b9f08a68de6dd8fc677965493cdbcb88f62b3' 
  AND token = 'b4lhefnVNZHxRIph3fAPozMhlBQtm0kbz9NqnlxZ1qw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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