SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '600aa80b986d2bafe8779834a590c61c317a7c4d8a043bc3815aec392af330b4' 
  AND token = 'pXFypbELdyfOBqrSh3OzuGJ7lmmk2mMBkcphtHR1p+k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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