Hypogaeic Species Research Articles

Subterranean Pitfall Traps: Is It Worth Including Them in Your Ant Sampling Protocol?

The use of subterranean traps is a relatively novel method to sample ants, and few studies have evaluated its performance relative to other methods. We collected ants in forests, savannas, and crops in central Brazil using subterranean pitfall traps and conventional pitfall traps placed on the soil surface. Sampling duration, soil depth, and sprinkling vegetal oil around traps all tended to affect the number of species found in subterranean traps. Sixteen percent of the species collected in subterranean traps were unique, and most of these had cryptobiotic morphology (i.e., were truly hypogaeic species). Surprisingly, however, subterranean and conventional traps were similarly efficient at capturing cryptobiotic species. Furthermore, subterranean traps captured far fewer species in total than conventional traps (75 versus 220 species), and this was true in all three habitats sampled. Sampling completeness increased very little using a combination of conventional and subterranean traps than using just conventional traps.

Descriptions of the first-instar larva of the hypogaeic species Neobidessodes limestoneensis (Watts & Humphreys) and of the third-instar larva of Hydroglyphus balkei Hendrich (Coleoptera: Dytiscidae: Bidessini) with phylogenetic considerations

Descriptions of the first-instar larva of the hypogaeic species Neobidessodes limestoneensis (Watts & Humphreys) and of the third-instar larva of Hydroglyphus balkei Hendrich (Coleoptera: Dytiscidae: Bidessini) with phylogenetic considerations

Descriptions of the first-instar larva of the hypogaeic species Neobidessodes limestoneensis (Watts & Humphreys) and of the third-instar larva of Hydroglyphus balkei Hendrich (Coleoptera: Dytiscidae: Bidessini) with phylogenetic considerations

The first-instar larva of Neobidessodes Hendrich & Balke (through the hypogaeic species N. limestoneensis (Watts & Humphreys)) and the third-instar larva of Hydroglyphus Motschulsky (through H. balkei Hendrich) (Dytiscidae: Bidessini) are described and illustrated in detail for the first time, including detailed morphometric and chaetotaxic analyses of the cephalic capsule, head appendages, legs, last abdominal segment and urogomphi. A cladistic analysis including 51 characters and 32 hydroporine taxa is performed, which supports the inclusion of both genera in the tribe Bidessini based on the absence of the primary pore ABc on the last abdominal segment. The third instar of H. balkei is characterized by the absence of secondary setae on the urogomphi and anterior secondary setae on the coxa, and the presence of 8–9 secondary setae on the mesofemur. On the other hand, the first instar of N. limestoneensis bears 14 lamellae clypeales on the anteroventral margin of the nasale. This species has evolved several morphological characters that are probably associated with its hypogaeic existence, including a lightly sclerotized body, relatively longer cephalic capsule and mandibles, a strongly reduced occipital foramen, absence of stemmata, and short claws. However, primary chaetotaxy apparently has remained as a very conservative expression of the phenotype.

BIODIVERSITY OF COLLEMBOLA IN SUGAR MAPLE (ACERACEAE) FORESTS

AbstractCollembola of 12 sugar maple forests of southern Quebec were surveyed through pit-light trapping and soil core extraction. These two sampling techniques were highly complementary, as pit-light traps are more efficient for sampling epigaeic species while soil core extractions are more efficient for hypogaeic species. A total of 108 species representing 38 genera and seven families was collected. Nine genera and 67 species are new records for the province of Quebec and 12 species are new records for Canada. The distribution of species among the different sites is summarized and taxonomic remarks are provided for 20 problematic species. A low percentage of the Quebec collembolan fauna is shared with Ontario and Newfoundland, which probably reflects an incomplete inventory of the fauna rather than highly different regional patterns in collembolan communities. The use of these two complementary sampling techniques is suggested to improve the inventory of Collembola in future research.

Rareness of certain Mediterranean ant species: fact or artifact?

A checklist of the ants recorded during five years in a small urban area (400 m2) in Sant Cugat (Barcelona, Spain) is presented. 23 species nest in the area, 7 species (hypogaeic or parasitic) probably nest and 5 species nest in the vicinity; five additional species have also been recovered from the area. The rarity of some of these (Leptanilla sp.,Hypoponera abeillei (Emery),Cryptopone ochraceum (Mayr),Smithistruma tenuipilis (Emery),Epitritus argiolus Emery,Trichoscapa membranifera Emery,Chalepoxenus muellerianus (Finzi),Anergates atratulus (Schenck),Plagiolepis xene (Schenck),Lasius carniolicus Mayr) and the high number of species suggest that a) rarity in Mediterranean ant species may be explained by the insufficient sampling in time of adequate microhabitats (hypogaeic species) or by the inconspicuousness of social parasitic species, and b) that previously published species lists of ants from Mediterranean habitats might be rather incomplete.

Distribution of the introduced Argentine ant (Iridomyrmex humilis) in natural habitats of the lower Sacramento Valley and its effects on the indigenous ant fauna

This study was designed to determine the extent to which the introduced Argentine ant (Iridomyrmex humilis), a pest in urban and agricultural environments, has invaded natural habitats in the lower Sacramento Valley, and its effects on the native ant fauna. Of four natural habitats surveyed (valley riparian woodland, foothill riparian woodland, blue oak-digger pine woodland, and chaparral), at 46 sites in Yolo and Solano counties, only valley riparian woodland was found to have been colonized by I. humilis. Riparian woodland sites occupied by I. humilis have permanent sources of water and tend to be environmentally degraded. Populations of I. humilis are common but patchily distributed along four principal riparian systems in Yolo and Solano counties (Ulatis Creek, Putah Creek, Cache Creek, and the Sacramento River). Observations indicate that patches of semidisturbed riparian woodland provide refuges from which populations of I. humilis may invade adjacent agricultural land, and vice versa. The species richness of native ants is markedly reduced at riparian woodland sites occupied by I. humilis. Among the common native ants, epigaeic (aboveground foraging) species are more susceptible to displacement by I. humilis than are hypogaeic species. The three most adversely affected species (Liometopum occidentale, Tapinoma sessile, and Formica occidua [ = moki]), which are absent from sites colonized by I. humilis, are dominant epigaeic ants; two of the three least displaced species (Stenamma diecki and S. californicum) are timid, cryptobiotic ants that forage in soil and leaf litter.

Behavioral Observations on African Army Ants of the Genus Aenictus (Hymenoptera: Formicidae)

Behavioral Observations on African Army Ants of the Genus Aenictus (Hymenoptera: Formicidae)