SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3bcc4af37584c50e270352b7d5aa55a9afddc3a1816066b59cd953b70202e698' 
  AND token = '5D3uLy9/bylB96zYBi7rTgMvyCtJgORio3ROSBqTfcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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