SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5151e3bbd9823a6c9333eae389fb3ae4c2d83340ec65263f91fcde6cc52f35bd' 
  AND token = 'cxYufiL7fw5qOLVUSR6lBE4YK/XDooGyCYeKJgYfiyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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