SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b5424c3a8f973735dd2f9bd32231cfa04ebfbb1f105d711cba8f399d31a2a4b' 
  AND token = 'qw7PhLL/gGZU84HtvBfgTQEPRA4AcZ8sd7NvSZEI15A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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