SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1fcb5f7459f479b517289c4b218136b25060c6e41a0855e3bf139662e9998c70' 
  AND token = 'PpOO1G+LcU5XtKjFuYxAbrTchwve+I3cjwyV2iFTOzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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