SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd33ceea126489ddd2a22af32efa5afee16518db7f26eadb69f313a57e65fb018' 
  AND token = 'Iu69hoynseYcO7bOnUXRpDsSAuiogVChcZvj49YLIrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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