SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f14cca41cf3edc29383c48cdd63dd9c69e1a14fe6f7baf41daf472954ee32155' 
  AND token = 'bkVn4Lostw1Y5ZNSJeaRnQcJ4NWulwhEZU4nP2vWpoc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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