SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb06beec91f463c429ed2240d07add75447402cf8553a20f8437e14df0599dff' 
  AND token = 'Bh6Ww2dAUZeO8jezrKt/ndANUoQvo33E4HC6Vpzt6RU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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