SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9cee9d2bd31f720b4e5223ff6126120d9f0255b3c525674f1c42a2193468ef95' 
  AND token = 'RtznH416WnjbSuSTjsGVBkbjkZEmNangAqtnMw72rKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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