SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc6cdaeb26fb9d4ce27a9cee9b30aee6244d2f32a53ebd187a92feb416f430ef' 
  AND token = 'Moc77tkXCEfoJrx/uzabvYaBPxSPPyjNMJNNxcFpu/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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