SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a688bd1920b693c4619cc2fc5ee07781c63c823637986d25909d707a3d7c9ff' 
  AND token = 'uUeOXgBdW+t209UNmWSpyslyIrUosRzNtAu7laxOY9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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