SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bbfcd68033b0d288669f9d707edf463df920a1def227c33ddd82988d9b522915' 
  AND token = 'uBiRVtmzUeVgbT//y8CWsIcrcQohhRujiF3Ugrnt2pc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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