SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5098f3db28236160a6c312448fa6b61d6347783b9a60c77a5867f81a3ea942d1' 
  AND token = 'XGwh+b9YLRasj9df3/LO9AzT0Zm1RjESBIcEPFZbqFI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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