SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ae42a473b15827278da5b82ed4f8b7544821cc83dd85b59cea2195e6539061af' 
  AND token = 'o+vmunGuY4a1KG8ojUi7MqFuy6gBlxt2KFJz10jQWxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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