SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c090f92ab9d358ee4ba9b5a58b3c691fe5f3b289a402c84181e40942a42f49ed' 
  AND token = 'DUynckhZEG3uqQXyrxjhZAu57Hc5iWJolhzd6o2DJco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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