« Back to Contents

Staphylinidae: subfamily Pselaphinae

Entomological Survey of Rio Bravo Conservation and Management Area, Belize

Christopher E. Carlton
Louisiana State Arthropod Museum
402 Life Sciences Building
Louisiana State University
Baton Rouge, LA 70803-1710 USA

Last update 4 June 1999

The staphylinid beetle subfamily Pselaphinae (formerly the family Pselaphidae) includes approximately 10,000 described species of small to minute beetles. Members of the group occur worldwide, and are ubiquitous inhabitants of forest litter habitats. All species for which data are available have predatory feeding habits or live as highly specialized inquilines in social insect nests. In contrast to the great diversity and wide distribution of the group as a whole, individual species tend to be restricted to narrowly defined habitats in limited areas. These attributes make the Pselaphinae an ideal group for biogeographic analyses and as an indicator taxon for overall forest litter diversity.

Few taxonomists have dealt with pselaphines historically, and fewer than 10 specialists in the World (two in the Western Hemisphere) are actively engaged in revisionary work on the Latin American fauna. Yet it is becoming increasingly apparent that, in terms of undescribed tropical species, the group rivals other hyperdiverse groups of insects such as microgastrine braconids and aleocharine staphylinids. Almost every collection of tropical pselaphines consists predominantly of undescribed species, and the generic limits within some groups, such as trimiine euplectines, are sufficiently vague to render generic assignments doubtful. In other cases the species cannot be assigned a name even though it is described because no one has compared the types and devised usable keys or illustrations, though the situation is slowly improving.

Taxa identified during this analysis, to my knowledge, represent the first records for Belize. I am not aware of any records for British Honduras in the earlier pselaphid literature, nor for Belize in the more recent material. Though there are probably scattered locality records for species in the country, I am certain that this is the first comprehensive analysis of a systematically sampled habitat in the country. It is a significant first step towards a understanding the pselaphine fauna of Rio Bravo. With continued sampling in the Rio Bravo Conservation Area, a comprehensive picture of regional pselaphine diversity in central american forests should emerge through comparisons with other low-altitude forests that also have been surveyed, including LaSelva in Costa Rica, and Barro Colorado Island in Panama.

Unless otherwise indicated, all specimens inventoried in the table below came from the moist tropical broadleaf forest in the vacinity of LaMilpa field station and archeological site. The other major Rio Bravo locality represented is Hill Bank Station, but limited collecting has been done there. All determinations are by C. Carlton. Annotations are given as footnotes. Specimens are deposited in the Louisiana State Arthropod Museum, LSU Agricultural Center and the Belizean National Collection, Belize National Plant Protection Service.

Taxa Genus species n Habitat/collection technique
Faronitae: Bythinoplectini Bythinoplectus dechambrieri Comellini [1] 3 FIT [2], berlese sample
Dimerini Barroeuplectoides sp. 1 28 Palm stump, rotten log, berlese samples
? B. sp. 2 15 Leaf litter berlese
Euplectitae: Panaphantini Thesium [3] sp. 1 4 Rotten log berlese
? T. sp. 2 4 FIT, rotten log berlese
Euplectini Bibloplectus sp. 1 2 FIT
? nr. Pycnoplectus sp. 1 2 Rotten log berlese
? Verabolus nr. subdendrus Park [4] 11 Rotten log berlese
? Undet. genus sp. 1 1 Rotten log berlese
? Rhinoscepsis dybasi Park [5] 129 Berlese samples, multiple litter types. Also collected at Hill Bank.
? Undet. Bibloporina sp. 1 12 Palm stump, berlese
Trimiini [6] Allotrimium sp. 1 1 ?
? Biblomimus sp. 1 8 FIT
? nr. Dalmosella sp. 1 2 Rotten log berlese
? nr. Hanfordia [7] sp. 1 53 Atta debris pile, berlese riparian litter. Also collected at Hill Bank
? nr. Hanfordia sp. 2 5 Rotten log berlese
? nr. Hanfordia sp. 3 197 Berlese samples, multiple litter types
? Tomoplectus sp. 1 30 FIT, berlese sample
? T. sp. 2 1 Rotten log berlese
? nr. Trimiopsis sp. 1 4 Rotten log berlese
? nr. Zonaira sp. 1 24 Rotten log berlese
? Undet. genus 1 sp. 1 1 Rotten log berlese
? Undet. genus 2 sp. 2 2 FIT
Jubini Endytocera cognata Sharp 4 FIT
? Sebaga sp. 1 10 FIT
? S. sp. 2 [8] 6 FIT, flood debris berlese
? S. sp. 3 4 Berlese sample
? S. spp. females 23 ?
Trogastrini Rhexinia sp. 1 1 Hill Bank, riparian litter berlese.
Batrisitae: Batrisini Arthmius bubalus Raffray 1 Light trap
? Euphalepsus sp. 1 3 FIT, yellow pan trap
? E. sp. 2 8 Berlese samples
? Undet. genus [9] sp. 1 34 Berlese samples
? Undet. genus sp. 1 3 Berlese sample
Goniaceritae: Brachyglutini: Eupsenina Eupsenius sp. 1 8 Malaise trap, FIT
? E. sp. 2 6 FIT, yellow pan trap
? E. sp. 3 1 FIT
? E. sp. 4 5 FIT
Brachyglutina Reichenbachia bicuspida Park [10] 3 UV light trap
? R. sarcinaria (Schaufuss) [11] 1 Light trap
? R. guatemalensis Fletcher [12] 3 Light trap
? Drasinus sp. 1 3 Pond edge berlese, riparian litter berlese at Hill Bank.
Pselaptina Eutrichites arizonensis Carlton [13] 6 Light trap
? Pselaptus/Xybaris sp. 1 17 FIT, riparian litter berlese, also known from Hill Bank
? Pselaptus/Xybaris sp. 2 12 Berlese samples
? Pselaptus/Xybaris sp. 3 5 Berlese samples, FIT
Decarthronina Decarthron cristatum Becker and Sanderson 5 Light trap
Tanypleurini Dalmoburis nr. brevicollis (Sharp) 9 Berlese samples
? Batrybraxis sp. 1 4 Berlese sample
Pselaphitae: Ctenistini Ctenisis sp. 1 6 FIT, light trap
Tyrini Hamotus sp. 1 6 Berlese samples, FIT
? H. sp. 2 2 Under bark
? H. sp. 3 8 Rotten log berlese
? H. sp. 4 1 Palm stump berlese
? Neotyrus nr. coptocolus Park [14] 1 Under oak bark at Rancho Delores (East Gate)
Clavigeritae[15]: Fustigerini Fustiger sp. 1 2 FIT
? F. sp. 2 1 Lindgren funnel trap
? F. sp. 3 10 FIT, berlese samples
? F. sp. 4 5 FIT, berlese samples
Totals ? 57 758 ?


[1] This species was described in 1985 based on specimens collected at Tikal, Guatemala.

[2] FIT=flight intercept trap

[3] There are approximately 12 described neotropical species of Thesium. No keys are available.

[4] This species was described from an all female series from Panama.

[5] This second most abundant species in my collections was not represented in the material Kovarik sent me. It was originally described from the Yucatan region of Mexico, and seems to be endemic to the region.

[6] This group of minute euplectines needs wholesale reorganization at the generic level. The group appears to be oversplit because the characters used to define generic limits are inconsistent among apparently closely related species. Many undescribed species cannot be reliably assigned to genus even though a fairly modern (1980) key is available.

[7] Hanfordia is based on a single species from Jamaica. I have seen a number of addition specimens that key near the genus from Dominican Republic, and I have seen females from central Florida.

[8] Sebaga 2 and 3 are either the same or closely related species. They are externally distinguishable and the genitalia are different, but not by much.

[9] This genus is assigned to the Batrisini with doubt.

[10] Also known from Guatemala, Guerro, Mexico, and Honduras.

[11] Also known from Oaxaca, Mexico, the Yucatan region, and Honduras.

[12] Also known from Guatemala, Oaxaca, Tabasco, and Veracruz, Mexico, and Honduras.

[13] Previously known only from Arizona, USA and one locality in Sonora, Mexico.

[14] This species was described from Panama.

[15] The Clavergeritae, insofar as is known, consists exclusively of highly specialized inquilines of social insects, mainly ants.