ARTS: Collaborative Research: Taxonomy and systematics of selected Neotropical clades of arachnids


We have studied museum material of Neogoveidae and Zalmoxidae (Giribet lab) and of Mimetidae, Linyphiidae and Malkaridae (Hormiga lab). We have clarified the taxonomy of the Neotropical Neogoveidae and produced a short monograph describing 8 new species and clarifying all the genera (Benavides & Giribet 2013). We also did field trips to Brazil (states of Amazonas and Roraima), Mexico, Costa Rica, New Zealand and Australia and sorted all the material from the LLAMA project, which is now catalogued in MCZbase ( and available on the web. We also produced the first phylogenetic hypothesis for another group of tropical arachnids, Ricinulei, which were not included in the original proposal, but have emerged as an interesting model for comparison for the biogeographical patterns observed in the target taxa (Murienne et al. 2013).

During fieldwork in Brazil (summer 2012) we collected ca. 50 specimens of Mimetidae (3 Gelanor spp, 1 Ero sp. and 2 Mimetus spp.) and numerous araneoids from several families (including target Linyphiidae taxa). We also collected all the local species of Neogoveidae, Zalmoxidae and Ricinulei. In Manaus, we visited the arachnological collection of INPA and sorted specimens of Gelanor (4 morphospecies) and of Linyphiidae (currently on loan to us).

Gelanor revision: Ca. 450 specimens of Gelanor have been studied. These 450 specimens belong to 8 different morphospecies. Digital stereoscope and Scanning Electron Microscopy images of the different somatic and genitalic features have been generated for some of the morphospecies. Sequences for the following six genes or gene fragments were generated for a total of 102 specimens of Mimetidae: 18S rRNA (~1800 bp), 28S rRNA (~2700 bp), 12S rRNA (~400 bp), 16S rRNA (~550 bp), histone 3 (328 bp) and Cytochrome c oxidase subunit I, (815bp). Additional sequences for some of the outgroup taxa were generated as well.

Linyphiid project: we have analyzed more than 380 lots Museum loans and specimens from our own fieldwork). This material corresponds to more than 3,200 specimens grouped in 93 morphospecies in 28 genera, 90% of them belonging to the focal group of the project (“large PME linyphiines”). 21 morphospecies were already imaged some already selected to SEM/ illustration work. We have also started examining the relevant type specimens from the Natural History Museum (London). A character matrix is in progress. From the material gathered, only 90 lots (18 genera and 49 morphospecies) are suitable to molecular work. The DNA sequencing of these specimens is in ongoing. Fieldwork in Mexico was carried out in cloud forests at Pico de Orizaba (October 2012) in which fresh material for molecular work as well as other data (natural history, web architecture, etc.) from the focal linyphiid group was obtained.

Malkarid project: Fieldwork in New Zealand and Queensland resulted in numerous specimens of Malkaridae. Morphospecies sorting of New Zealand fauna (12 spp) and of Malkara (Australia, 36 spp.) has been completed. Hormiga visited the CAS collection (December 2012) to sort and borrow additional specimens for the project. We are now starting the species descriptions. 26 malkarid specimens have been sequenced and a phylogenetic analysis is now in progress.

To date we have described eight new species of Neogoveidae (Opiliones, Cyphophthalmi) from the Neotropics and have produced a monographic revision of the family in the Neotropics (Benavides & Giribet 2013). We have also provided the first phylogenetic analysis of Ricinulei with an evolutionary study of their diversification in the tropical forests of the Americas and Africa (Murienne et al. 2013), in collaboration with the two laboratories. In addition we have generated Sanger sequence data for more than 100 Neotropical arachnids and Illumina transcriptomic data for one Zalmoxidae and three spiders (Unpublished). We have characterized eight species of Gelanor and more than 40 Malkaridae, which are now in the process of being described. We are sorting linyphiid collections to clarify the circumscription of the target clade and to start the descriptive work. PI Hormiga worked with project collaborator N. Scharff on a paper that addressed palpal homologies in linyphiids (Gavish et al. 2013).


The Hormiga laboratory currently has three trainees, two doctoral students and one undergraduate. In 2012 the Hormiga lab hosted an additional doctoral trainee, from Museu Goeldi Brazil) and a MS trainee (from Univ. of Sao Paulo-Instituto Butantan) (both came to GW with their own funding). Both of them worked on Neotropical spider groups, although not directly related to the target projects, they offer a very good complement.

Former Giribet lab graduate student Prashant Sharma (during his transition to the current postdoctoral position) trained a Brazilian undergraduate on scanning electron microscopy and morphology of Zalmoxoidea during a three-month internship. This study is currently under evaluation in Cladistics (Gainett et al. submitted). Giribet is seeking new students to work in the project, but this has been delayed slightly due to the admissions cycle from last year, which failed to yield a suitable candidate.

In addition, we have trained two Brazilian students (Lidianne Salvatierra and Willians Porto) in the field techniques required for collecting cryptic soil arachnids. Lidianne Salvatierra will be visiting the Hormiga laboratory for one year in 2013-2014. Collaborator Ana Tourinho is visiting the Giribet laboratory for one year from July 2013 to June 2014. One manuscript is currently under review (Salvatierra et al. submitted).

In May 2012 all project participants met at GW to discuss progress and to plan future research goals.


We gave 5 lectures during our visit to INPA (Manaus) in June 2012, encompassing all the areas of our project. The lectures were given by the PIs Hormiga and Giribet and by three trainees (Benavides, Silva-Moreira, and Ballesteros). We further presented our research in other venues, including the first Austral Biogeography workshop (Sydney, December 2012) and at the regular seminar series of the Department of Zoology at the Smithsonian (December 2012) and the International Congress of Arachnology (Taiwan, 2013). PI Hormiga gave a seminar at the Smithsonian (May 2012).

Outreach Activities

During a field trip to the Amazon river, we gave a public interactive lecture about arachnids to one of the river communities where we sampled, in the state of Roraima (Brazil). The talk was presented in the local church and all the younger members of the community, and many of the adults, attended. The goal of the talk was to make the local community understand the importance of maintaining their unique biodiversity and the benefits that a well structured pristine forest can give them in terms of natural resources as well as revenue due to ecotourism.


Hormiga, G. and C.E. Griswold. In press. Systematics, Phylogeny and Evolution of Orb-weaving Spiders. Annual Review of Entomology (2014).

Dimitrov, D., Lopardo, L., Giribet, G., Arnedo, M. A., Álvarez-Padilla, F., and Hormiga, G. 2012. Tangled in a sparse spider web: single origin of orb weavers and their spinning work unravelled by denser taxonomic sampling. Proceedings of the Royal Society B: Biological Sciences 279, 1341-1350. doi:10.1098/rspb.2011.2011

Gainett, G., Sharma, P. P., Pinto-da-Rocha, R., Giribet, G., and Willemart, R. H. 2013. Walk it off: Predictive power of appendicular characters toward inference of higher-level relationships in Laniatores (Arachnida: Opiliones). Cladistics 29. doi:10.1111/cla.12029

Gavish-Regev, E., G. Hormiga and N. Scharff. 2013. Pedipalp sclerite homologies and phylogenetic placement of the spider genus Stemonyphantes (Linyphiidae, Araneae) and its implications for linyphiid phylogeny. Invertebrate Systematics 27(1): 38-52.

Benavides, L.R. & Giribet, G., 2013. A revision of selected clades of Neotropical mite-harvestmen (Arachnida, Opiliones, Cyphophthalmi, Neogoveidae) with the description of eight new species. Bulletin of the Museum of Comparative Zoology, 160: 1-44.

Murienne, J., Benavides, L. R., Prendini, L., Hormiga, G., Giribet, G. 2012. Forest refugia in Western and Central Africa as 'museums' of Mesozoic biodiversity. Biology Letters 9: 20120932.

Giribet, G., and Edgecombe, G. D. 2013. Stable phylogenetic patterns in scutigeromorph centipedes (Myriapoda : Chilopoda : Scutigeromorpha): dating the diversification of an ancient lineage of terrestrial arthropods. Invertebrate Systematics.

Scharff, N. and G. Hormiga. 2012. First evidence of aggressive chemical mimicry in the Malagasy orb weaving spider Exechocentrus lancearius (Arachnida: Araneae: Araneidae) and description of a second species. Insect Systematics & Evolution 70(2): 107-118.

Salvatierra, L., Tourinho, A. L., and Giribet, G. 2013. Description of the male, larva and nymphal stages of Cryptocellus iaci (Arachnida, Ricinulei), with an overview of tarsal sensilla and other integumental structures. Zootaxa 3709, 149-161.

Vahtera, V., Edgecombe, G. D., and Giribet, G. In press. Phylogenetics of scolopendromorph centipedes: Can denser taxon sampling improve an artificial classification? Invertebrate Systematics.

Fernández, R., and Giribet, G. (submitted). Historical biogeography and evolutionary dynamics in ancient species: constant radiation in Aoraki denticulata (Arachnida, Opiliones, Cyphophthalmi) does not support the Oligocene drowning episode of New Zealand. Molecular Ecology.