SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b5025b02ef3130a9874f827a4bc79de5c9873cb95b843a40d096fb22141bb74' 
  AND token = 'USsNIkxn/mQtQ9KVFaQmb4rwKlFE1UujH9BiOduooDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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