Search for: All records

Subterranean arthropods are important components of soils and contribute essential food-web functions and other ecosystem services, however, their diversity and community composition has scarcely been assessed. Subterranean pitfall traps are a commonly used method for sampling soil habitats in Europe but have never been widely implemented in the Americas. We used subterranean pitfall traps to sample previously unsurveyed arthropod communities in southwestern Virginia, U.S. Traps were placed in shallow subterranean habitats (SSHs), underground habitats close to the surface where light does not penetrate, and more specifically at the interface between the soil and underlying “milieu souterrain superficiel”—a microhabitat consisting of the air-filled interstitial spaces between rocks (abbreviated MSS). In total, 2,260 arthropod specimens were collected constituting 345 morphospecies from 8 classes, 33 orders, and 94 families. A region of the mitochondrial cytochromecoxidase subunit I (COI) gene was amplified and sequenced, and objective sequence clustering of 3% was used to establish molecular operational taxonomic units (mOTUs) to infer observed species richness. In all, 272 COI barcodes representing 256 mOTUs were documented for rare soil-dwelling arthropod taxa and are published to build a molecular library for future research in this system. This work is the first taxonomically extensive survey of North American soil-dwelling arthropods greater than 10 cm below the soil surface. 

The identity of Striaria californica Cook, described in 1899 from a single female, is established on the basis of additional specimens collected by Cook in 1929 and determined to be that species by Loomis (1936) as well as specimens from the San Francisco Bay region, likely to be from near the original collection locality. We propose Amplaria californica (Cook, 1899) new combination. A new genus, Bayaria Shear & Marek n. gen., is established for Striaria nana Loomis, 1936 Bayaria nana (Loomis, 1936) new combination. Striaria carmela Chamberlin, 1947, is a junior synonym of Bayaria nana. A key to the 16 genera of Striariidae and an annotated checklist of the 52 species are provided. 

The millipede fauna inhabiting deep soil are poorly known. They are small and threadlike, slow moving, lacking pigmentation, and rarely encountered due to their obscure underground way of life. One family, the Siphonorhinidae, encompasses four genera and 12 species in a fragmentary distribution in California, southern Africa, Madagascar, the Malay Archipelago, and Indo-Burma. The family is represented in the Western Hemisphere by a single genus, Illacme Cook & Loomis, 1928 from California, with its closest known relative, Nematozonium filum Verhoeff, 1939, from southern Africa. A new species of this family is documented from soil microhabitats in the Los Angeles metropolitan area, Illacme socal Marek & Shear, sp. nov. Based on this discovery and the recent documentation of other endogean millipede species, we show that these grossly understudied subterranean fauna represent the next frontier of discovery. However, they are threatened by encroaching human settlement and habitat loss, and conservation of this species and other subterranean fauna is of high importance. 

We describe three new genera and four new species of small, litter-dwelling millipedes from the states of Oregon and Washington, USA: Miniaria ramifera, n. gen., n. sp., Miniaria richarti, n. gen., n. sp., Tigraria oregonensis, n. gen., n. sp., and Kingaria prattensis, n. gen., n. sp. Some of the unusual characters of these species are discussed, including a new type of sensory array on the third tarsus of males and a newly observed mandibular gland. 

Petra sierwaldae, n. gen., n. sp. is described from males and females collected at four localities in Kootenai County, Idaho, USA. The new genus is defined by its unique gonopod and ninth leg anatomy, a notched collum and single ommatidium on each side of the head, and lacking third coxal flasks as well as having modified fifth coxae. 

The following new genera and species of Striariidae are described from the states of California, Oregon and Washington: Nototrisaria ornata n. gen., n. sp., Maraplia napa n. gen., n. sp., Maraplia chico n. gen., n. sp., Maraplia schusteri n. gen., n. sp., Lamparia curryensis n. gen., n. sp., Lamparia bentonensis n. gen., n. sp., Lamparia pratensis n. gen., n. sp., Lamparia millicoma n. gen., n. sp., Rampalia cheathamensis n. gen., n. sp., Plaramia arcata n. gen., n. sp., Plaramia johnsonae n. gen., n. sp., Ralampia complexa n. gen., n. sp., and Ralampia filamentosa n. gen., n. sp.. The new species are all very small millipedes, 5.5 mm or less in length and with two or three ommatidia on each side of the head or blind. The majority have the sixth metazonital crest larger than the other crests and extended horizontally, so that the animals have the general appearance of having paranota. A new key to striariid genera is presented. 

The millipede genus Cherokia Chamberlin, 1949 is a monospecific taxon, with the type species Cherokia georgiana (Bollman, 1889). The last revision of the genus was made by Hoffman (1960) where he established three subspecies. Here we used molecular phylogenetics to assess the genus and evaluate whether it is a monophyletic group, and if the subspecies are each monophyletic. We included material from literature records and three natural history collections. Newly collected samples were obtained through a citizen science project. Morphological characters underlying subspecies groups—the shape of the paranota, body size, and coloration—were evaluated. A molecular phylogeny of the genus was estimated based on DNA sequences for seven gene loci, and a species delimitation analysis was used to evaluate the status of the subspecies. The documented geographical range of Cherokia in the United States was expanded to include a newly reported state record (Virginia) and about 160 new localities compared to the previously known range. Morphological characters, which included the shape of the paranota and body size that had been historically used to establish subspecies, showed clinal variation with a direct relationship with geographical distribution and elevation, but not with phylogeny. Coloration was highly variable and did not accord with geography or phylogeny. The phylogeny recovered Cherokia as a monophyletic lineage, and the species delimitation test supported the existence of a single species. The subspecies Cherokia georgiana ducilla (Chamberlin, 1939) and Cherokia georgiana latassa Hoffman, 1960 have been synonymized with Cherokia georgiana . The molecular and morphological evidence showed that Cherokia is a monospecific genus with the sole species, Cherokia georgiana , being geographically widespread and highly variable in its morphology. 

A new species, Amplaria oedipus, is described from Oregon, USA. Males of the new species have greatly inflated pyriform tarsi on the 5th and 6th legpairs, which is a secondary sexual modification previously not known from any other millipede. 

Two new genera and species, Stegostriaria dulcidormus (Trisariinae) and Kentrostriaria ohara (Striariinae), are described from Oregon and Idaho, respectively. The new species are distinct from any other striariids, and indeed from any other chordeumatidan millipedes, in having the second dorsal crests greatly enlarged, giving them a fanciful resemblance to stegosaurid dinosaurs. In spite of this similarity, the two species are so distinct they cannot be accommodated in the same genus or the same subfamily. The exaggerated metazonital crests are therefore attributed to convergent evolution. We present a key to the genera of the family Striariidae.