Dr. Erik J. van Nieukerken

Research interests

Pattern and biodiversity of hostplant relationships in leafmining Lepidoptera

 Catterpillars of Enteucha acetosae on common sorrel (Rumex acetosa), Germany, Eifel.

Since 1978 the main object of my studies is the micro-moth family Nepticulidae. These extremely small moths (wingspan 3-10 mm) occur world-wide with ca. 800 described species and an estimated total of 2.500 species. The larvae make tunnels in leaves, or more rarely in stems or fruits, better known as leaf-mines (stem-mines etc.).They are amongst the most hostspecific phytophagous insects. It is estimated that about 90% of the species is at least specific for the hostfamily, in most cases even for genus or species. This makes this group an ideal model for studies on the evolution of host associations. It is assumed that host associations are conservative characters, which only rarely change in the course of evolution. Major changes occur in particular after major changes in climate and vegetation. In this project we aim to analyse the pattern in connection with a study on the phylogeny of the parasites in order to explain part of this evolution, and to find general patterns in the evolution of host relationships, in particular in the insect order Lepidoptera. We also hope to contribute to the explanation of the high biodiversity of insects in some ecosystems, particularly in the tropics.

Bohemannia quadrimaculella, moth from Italy.

Up to now the study has centered on Western Palaearctic species, particularly in the Mediterranean region, with currently a focus on the genera Ectoedemia Busck, Parafomoria Borkowski and Trifurcula Zeller. Since 2003 molecular methods are also used in co-operation with Dick Groenenberg and others. This includes DNA barcoding for the identification of larvae or unknown adults. In 2008-2009 Camiel Doorenweerd worked on the molecular phylogeny and DNA barcoding of the subgenus Ectoedemia. Papers based mailny on the European fauna are now in preparation and a first has been published in 2012 (see below). DNA barcoding results are partly visible to the public on the BOLD website and more are following soon. In future we want to extent this study into Ectoedemia and Stigmella of the Holarctic region, to study common patterns in the evolution and hostplant relationships. In 2011 student Suzanne van der Hoeven did a study on the phylogeny of Trifurcula.

In the last decade I have worked in Southeast and East-Asia and also Australia. In this large region Nepticulidae are still insufficiently known. However, material is now gradually becoming available from several parts of Asia. Fieldwork was carried out in Nepal (1981), China (1984), Vietnam (2001, 2003, 2009), Queensland (2004), Borneo (2005) and Florida (2006). Fieldwork has started again more widely in the Holarctic region in order to gather material for phylogenetic studies: USA Northwest (summer 2010), USA southeast (fall 2010), United Arab Emrirates (2011). For the identification of tropical hostplants we co-operate with plant systematists and with Barbara Gravendeel (National Herbarium, Leiden) we started to use DNA barcoding as an identification tool with student Johan Vlasman ( Hogeschool van Amsterdam) in 2010 out barcoding of tropical hosts.

In this project I co-operate with many specialists and institutes. Apart from Nepticulidae, some studies will involve other families of Microlepidoptera, notably leafminers (Heliozelidae, Tischeriidae, Gracillariidae).

Faunistics of Lepidoptera

Together with Dutch amateur and professional Lepidopterists, we produce annual faunistic reviews in the journal 'Entomologische Berichten'. These are available as pdf online in the Naturalis repository.

I am chairman of the Dutch Working group Lepidoptera Faunistics (WVF = "Werkgroep Vlinderfaunistiek Nederland "), which operates under EIS the Netherlands . This group is holding a large database with millions of records of all groups of Lepidoptera, from literature sources, collections and hundreds of volonteers. In co-operation with the Dutch Butterfly Association (Vlinderstichting) we publish maps of the macroleps on the site of Vlindernet , and the micro's we publish on the site microlepidoptera.nl   For the latter I am also one of the collaborators. Data manager for the database is Dr. Willem Ellis, who also shares my interest for leafmines (see his leafminer site ).

Lepidoptera of South-East Asia

During the fieldwork in Vietnam and Kalimantan (Borneo) I also collected other moths at light, in order to increase our knowledge of the South East Asian fauna, of which our museum has already a strong collection (but mainly Java, Sumatra and New Guinea).

The project in Kalimantan in 2005 was on invitation by Tropenbos Indonesia, who wanted a Biodiversity Assessment of the Gunung Lumut Protection Forest (Kalimantan Timur). The ca 3000 moths collected in the three weeks of fieldwork have been mounted, and the majority of macro's identified with the aid of Jeremy Holloway's book series Moths of Borneo. We took photographs of representatives of all species and took legs for DNA barcoding at BOLD. At the moment we have 615 recognised macro's on the BOLD website. This work was carried out by Guido Keijl. In 2010 two students of the Leiden University, Els Baalbergen and Lisa Parie sorted the micromoths and pyraloids to morphospecies and took  photographs and legs for barcoding. With all these data we aim to make a biodiversity analysis of the area.

In 2011 student Amanda Oudenes started similar work on Geometridae of  Vietnam.

International co-operative projects 

Fauna Europaea

 Ole Karsholt (Zoological Museum Copenhagen) and I are group co-ordinators for the Lepidoptera (moths). The second version (2.1) is available online since late 2009 (see Fauna Europaea), the first version was published in 2004. We update it in principe continuously, although new updates are posted at irregular intervals. We have the intention to publish this list also on the SEL website with taxonomic order added.

Leptree

Leptree.net is an international, community collaboration dedicated to advancing progress toward a phylogenetic tree for all Lepidoptera. I am involved as "twig leader" for Nepticuloidea.

Lepidoptera barcoding  

I am involved in several DNA barcoding projects of Lepidoptera, e.g. on BOLD and the iBOL AllLeps project. A new barcoding facility is currently being set up here at the NCB Naturalis in Leiden, see the website .