SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6c8ce329c5e1f437cc7c97cdc56f5ca250e9dfec7e95ff50de31cac33859fdd1' 
  AND token = 'lPl6SF56rGn36hS5YqXv/ZPu15tTg12eynk14wJSWRs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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