SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d060d7ab67f852941c9ecc247253b137cd56304f654f54279a36273901a65d1' 
  AND token = 'RMJSGGVZcTFR9o7rLvA3H7SZCtmWlazFiICpKVGAPOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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