SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b8cfcf268a1dfb61d36c39a162a4d9f4069c06382c4c5fc98a8fc1de5d233c05' 
  AND token = 'Aq9ch+tKFwZWt2l/DlGr//VpK1EL2duQQRITK4ImWlg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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