• 1. Crustaceans

1.1. Platyarthrus schoblii Budde-Lund, 1885 (Isopoda, Oniscidea) 

This tiny (2-4 mm), whitish woodlouse, is known from the Azores, the north Mediterranean and Black Sea coasts. It inhabits the nest of several species of ants in the genera Formica, Lasius, Linepithema and Messor. It was found outside of that region, in Hungary, within the nests of Lasius neglectus. For a summary update of its distribution and biology see Tartally et al. (2004) at 

Want to see it alive? Click here: (video:16”; 2.3 Mb. View/download).

1.2. Platyarthrus hoffmannseggii Brandt, 1833 (Isopoda, Oniscidea)

This woodlouse is widely distributed in Europe. It has been detected in nests of L. neglectus in Belgium (Dekoninck et al. 2007), showing that this ant is able to host also local woodlouse species. See the distinct aspect of the two Platyarthrus species in the following image.

(Image from Tartally et al. 2004: A: P. schoblii; B: P. hoffmannsseggii)


  • 2. Coleoptera

2.1. Clytra laeviuscula Ratzeburg, 1837 (Chrysomelidae)  

(Image from http://culex.biol.uni.wroc.pl/cassidae/European%20Chrysomelidae/clytra%20laeviuscula.htm

A few larvae were found inside the nest of Lasius neglectus at Sant Cugat (Barcelona, Spain) nesting at the base of a poplar tree (Populus nigra), close to the railway. One male eclosed at the laboratory. Those larvae are supposed to eat ant eggs and larvae.


2.2. Amphotis marginata (Fabricius, 1781) (Nitidulidae) 

 (Image from www.zin.ru/Animalia/ Coleoptera/rus/ampmarhe.htm ) 

One beetle was recovered in the nest of Lasius neglectus at an outpost of the extensive Seva (Barcelona, Spain) supercolony. It feeds by forcing regurgitation in returning laden workers. If attacked, the beetle crouches down and is protected by its peculiar cuticular flanges. 

  • 3. Orthoptera

3.1. Myrmecophilus (Myrmecophilus) acervorum Panzer, 1799 (Gryllidae) 

Myrmecophilus crickets are to be found within the nests of many ant species. Female (inset: ovipositor).

The small, blind crickets, were found in the nest of L. neglectus from five populations in Barcelona province: Bellaterra (one female, 2.iv.2003; one male, 16.vi.2004), Seva (one male, one female, 30.iv.2003), Begues (one juvenile, 20.x.2005), Badalona (27.ix.2005) and Matadepera (1 male, 3 females, 3 nymphs, 22.x.2009, ) (Espadaler & Olmo, 2011). Another possible name to apply is M. myrmecophilus but its status as a good species is still unsettled. Have a look at those nervous, interesting crickets! (video: 20”; 2.8 Mb. View/download).

  • 4. Collembola

4.1. Cyphoderus albinus Nicolet, 1842 (Cyphoderidae)

This springtail has been recently found in nests of L. neglectus in Belgium (Dekoninck et al. 2007). The species is a common occurrence within nests of European ants.

(Image from http://www.geocities.com/~fransjanssens/taxa/collembo.htm)



  • 1. Aphids

1.1. Aphids tended by Lasius neglectus in Spain. The ants has been recorded from >30 tree species in Spain; therefore, it is likely that the aphid species involved are also varied. Here are a few examples.



On a young, lateral shoot of Quercus ilex.



Tending blackish aphids on Cirsium eriophorum.


Tending Lachnus roboris on a branch Quercus ilex. Lachnus roboris (Lachnidae). This enormous aphid, feeding on Quercus ilex, is an important honeydew source for Lasius neglectus at the populations of Bellaterra and Seva. See him walking: (video: 23”; 3.2 Mb. View/download).

The emission of plant volatile organic compounds (VOCs) depends on temperature and light.  Other factors such as insect herbivory also may modify VOC emission. Aphid feeding promotes the release of new compounds and changes the composition of plant volatile mixtures. The effect of Lachnus roboris aphids and two different tending ant species on terpene emission rates of 4-year-old holm oak (Quercus ilex) saplings was investigated during a field experiment. There were five treatments: saplings alone (T1), saplings infested with L. roboris aphids (T2), saplings infested with aphids tended by the local ant Lasius grandis (T3), those tended by small colonies of the invasive ant Lasius neglectus (T4), and those tended by large colonies of the same invasive ant species (T5).
The infestation by Lachnus roboris elicited the emission of Δ3-carene and increased the emission of myrcene and γ-terpinene. Terpene emissions were modified depending on the tending ant species. Attendance by the native ant L. grandis increased α and β- pinene and sabinene. Attendance by the invasive ant L. neglectus only decreased significantly the emission of myrcene, one of the major compounds of the Q. ilex mixture.
Aphid abundance was not correlated with total terpene emission rates. These results highlight that aphids and tending ants may change terpene emission rates, depending on the ant species (Paris et al. 2010).

  • 2. Birds

2.1. Lasius neglectus – and other ant species- as prey for birds

In February and March 2000, and along the sideways of some non urbanized lots, we observed that the soil was excavated all along. A bird was seen at that level and thereafter droppings were recovered from the same area. Here are and this is what they contained.  Birds in the Picidae are known to feed extensively on ants but we cannot tell for sure the bird we saw belonged in that family.


Bird droppings

Close-up view of content

Heads and other debris of one Camponotus, three Crematogaster scutellaris and a dozen Lasius neglectus.

Mean number of individual ants per g dry mass of excrement is 1880 (n=3 fragments). Dry mass of two complete excrements is 0.36g and 0.72g, that is, they would contain 680 and 1360 ants


  • 1. Laboulbeniales

Laboulbeniales (Fungi) are an infrequent find when growing on ants. Herraiz & Espadaler (2007) report Lasius neglectus as a new host for Laboulbenia formicarum, which is also a new mycological addition for continental Europe. The fungus was known hitherto mainly from North America and from an extraneous locality in Madeira. Heavily infested ants were foraging normally on Tamarix gallica (salt cedar trees) planted along a seaside walk at L’Escala, in North-East Spain. The infestation is spatially much extended (540 m), probably because of the supercolonial social structure of the host ant. Workers of eleven additional ant species from the same locality were collected but none was infested. The promenade was destroyed by a sea storm (December 2008) and has been reconstructed. Many new trees have been planted and this has much reduced the Lasius neglectus presence, although the fungus infestation persists there (October 2017). Recent localities for this unexpected pair are Douarnenez (France; J. Wagenknecht leg.), Saintes-Maries-de-la-Mer (France; C. Lebas leg.) and Gif-sur-Yvette (France; S. Tragust leg.) (Espadaler et al. 2011). The geographical distribution of the ant-fungus interaction is not uniform (Tartally & Báthori, 2015). This fungus does not seems to harm the hosts: ants forage as usual, without any visible alteration in behaviour. It is a very rare event that two separately introduced organisms -the fungus from America, the ant from Asia- meet and interact. In this case the interaction seems to boil down to any negative effect for the ant. Obviously, it should be seen as positive for the fungus. Laboratory observations, though, show that the infestation level with Laboulbenia weakens the reaction of ant hosts to experimental infection with the entomopathogenic fungus Metarhizium brunneum. (Konrad et al. 2015).

Long-term monitoring of the prevalence and intensity of infection in two populations (supercolonies) over 4–10 years revealed epizootic spread of the parasite with a 14 % annual increase in prevalence until ca. 80 % of all ants were infected (Tragust et al 2015). Currently it is not possible to predict what will be the long-term consequences for L. neglectus supercolonies infected with L. formicarum. Population crashes are frequently observed in invasive species and although disease has often been invoked to be the cause, documentation is scarce. On the other hand it has been argued that evolution of specialized parasites in the environmentally buffered nests of some insects will lead to the evolution of lower virulence.

Leg of Lasius showing many thalli of the fungus all over the femur and tibia. Inset: mature thallus of Laboulbenia formicarum (image by S. Santamaria).

Seaside walks along the beach at L’Escala (42º 7'N, 3º 7'E). Ants were nesting at the base of salt cedar trees and foraging up on tree trunks.




Page authors: Xavier Espadaler  (Xavier.Espadaler@uab.es) and Víctor Bernal (v.bernal@creaf.uab.es).