Ernest C. Bernard

Soil nematode biodiversity

SummaryNematodes are the most abundant metazoans in soil, and are exceeded in species diversity only by the arthropods. Estimates of nematode diversity in natural and agroecosystems have been based on both species-level taxonomy and trophic-level guilds. Because trophic groups do not act in a unitary manner with respect to environmental alterations, species-level analysis is more meaningful and should be preferred for most kinds of investigations. Nematodes of a biotope have often been considered as mere assemblages, but there is increasing evidence that certain plant associations have characteristic groups of species. This concept has been used by Bongers to develop a maturity index relating nematode families and site stability, and to identify assemblages that colonize disturbed soils. Major constraints on detailed ecological studies of soil nematode faunas are an incomplete understanding of trophic groups and their subsets, the need for repeated sampling of seasonally variable populations, and a severe shortage of taxonomy-competent persons, especially for microbial feeders.

Survey of Pogonognathellus Börner (Collembola: Tomoceridae) in the Southern Appalachians Based on Morphological and Molecular Data

ABSTRACT Pogonognathellus Börner is the most common genus of tomocerid Collembola in the southern Appalachian region of the United States. Scale pattern, cuticle color, and molecular data were used with morphology and chaetotaxy to reappraise the members of this genus. P. bidentatus and P. elongatus are confirmed as well-marked species; P. nigritus Maynard is removed from synonymy with P. elongatus and reestablished as a valid species, and a neotype is designated. Two new species are described. Pogonognathellus danieli n. sp. from a cave in Great Smoky Mountains National Park resembles the California cave species P. celsus but possesses clubbed tenent hairs on all tibiotarsi; in P. celsus, the tenent hairs are pointed. P. mystax n. sp. is related to the “P. flavescens complex” but differs in having a purple clypeus and a prominent band of light scales along the posterior edge of each tergite. Many collections of P. flavescens-like and P. dubius-like specimens were made but molecular analysis indicated that these specimens consisted of four P. dubius-like taxa and four P. flavescens-like taxa. True P. flavescens from Sweden (type locality) were molecularly distinct from the putative American P. flavescens included in the analysis. A tentative phylogenetic tree indicated three clades of southern Appalachian Pogonognathellus: one clade containing P. bidentatus; another clade containing species with posterior cephalic macrochaetae but without anterior macrochaetae on the fourth abdominal tergite (Abd. IV; P. elongatus, P. nigritus, and an undescribed species); and a third clade without posterior cephalic macrochaetae but with one pair of anterior macrochaetae on Abd. IV (P. danieli, P. mystax, and eight undescribed species).

Pratylenchus hippeastri n. sp. (Nematoda: Pratylenchidae) from amaryllis in Florida with notes on P. scribneri and P. hexincisus.

A new root-lesion nematode Pratylenchus hippeastri n. sp. is described from amaryllis (Hippeastrum spp.) in Florida. The new species is characterised by a combination of the following morphological features of females: slender body, flat, plain and smooth face, head with two lip annuli, an incomplete third annulus, and with second lip annulus thicker than first, ellipsoidal stylet knobs, rectangular empty spermatheca with large round cavity, and conoid tail with bluntly pointed terminus usually showing a ventral constriction, or subhemispherical and smooth. The ranges of morphometric characters of P. hippeastri n. sp. overlap with those of P. scribneri and P. hexincisus. These three species also share some morphological and biological features such as two lip annuli, an empty spermatheca and similar lateral fields, but differ in the morphology of head patterns (smooth face in P. hippeastri n. sp. vs divided face in the others) and tail termini (hemispherical and subhemispherical in P. scribneri and subdigitate in P. hexincisus vs bluntly pointed in P. hippeastri n. sp.). A reference population of P. scribneri from Ohio and one of P. hexincisus from Tennessee were obtained during the course of unsuccessful attempts to recover P. scribneri at the type locale in Tennessee. The D3 rDNA sequences of the reference populations matched GenBank sequences for these two species. Small morphological differences between the P. scribneri population from Ohio and the P. scribneri lectotype occurred in the shape of stylet knobs (ellipsoidal vs round) and spermatheca (round with a central cavity vs oblong) and also in the length of the pharyngeal overlap (longer in the reference population). These morphological differences cast doubt about the identity of the lectotype, which may be P. hexincisus. New morphological details were obtained for P. hexincisus from Tennessee, which included a divided face, an almost rectangular empty spermatheca with a central cavity and subdigitate tail termini. Based on our phylogenetic inferences from DNA sequences P. hippeastri n. sp. is more closely related to P. zeae and a Florida population of P. loosi than to P. scribneri or P. hexincisus.

Review of Tuxenentulus and Fjellbergella Species (Protura: Acerentomidae, Acerentominae)

ABSTRACT Two new species of Tuxenentulus Rusek, 1974 and Fjellbergella Nosek, 1978 are described: Tuxenentulus solncevae n. sp. from the Russian Far East and Fjellbergella uteorum n. sp. from Colorado. T. solncevae n. sp. is characterized by short and broad foretarsal sensilla c and e, presence of cephalic seta d6 on head, presence of seta Pla on abdominal tergites I–VI, and sensilliform accessory setae on segments I–VI. F. uteorum n. sp. (Colorado) possesses 19 posterior setae on abdominal tergite VII, including median seta Pc, and 14 setae on tergite IX. A key to known world Tuxenentulus and Fjellbergella spp. is provided.

Critique of the Article “Collembola (Springtails) (Arthropoda: Hexapoda: Entognatha) Found in Scrapings from Individuals Diagnosed with Delusory Parasitosis”

In a recently published paper, Altschuler et al. (2004) argued that Collembola (springtails) can cause “stinging/biting and/or crawling” sensations. The collembological community has been highly critical of this report, but has discussed this issue primarily among the members of this community. However, allegations that springtails cause various dermatological problems, severe itching, and related symptoms have made it into the widely read on-line encyclopedia Wikipedia (http://en.wikipedia.org/wiki/Delusory_parasitosis, accessed August 8, 2008: “People with delusional parasitosis are likely to ask for help not from psychiatrists but from dermatologists, pest control specialists, or entomologists.”). The medical community has firmly rejected the linkage of insects and widespread dermatitis (Berrios 1985, De Leon et al., 1982, Gupta & Voorhees 1990, Wykoff 1987). Janssens and Christiansen (2007) do acknowledge that an allergic reaction to Collembola tissue or integument on the part of some sensitive people is possible and might lead to the crawling-on-skin irritation symptoms. Various sources and publications, however, have gone much farther and have alleged that some springtails may parasitize humans. This allegation is entirely inconsistent with springtail biology, and no such phenomenon has ever been scientifically confirmed. (For a summary of the literature on this subject, see .) Springtails sometimes can be abundant indoors in damp places such as bathrooms and basements, and under such circumstances may be found on one’s person, but this is only accidental. Claims of persistent human skin infection by springtails may indicate a neurological problem, or else delusory parasitosis, a psychological not entomological problem. Berenbaum (2005) commented on the Altschuler et al. paper, suggesting that the report was based on pareidolia; that is, the researchers simply imagined that they saw springtail-like shapes in the images when there were no springtails actually present. In this paper, we more specifically and categorically refute the contention of Altschuler et al. (2004). Volume 119, Number 5, November and December 2008 537

Collembola of Rapa Nui (Easter Island) with descriptions of five endemic cave-restricted species.

Eight species of Collembola are reported from recent collections made in caves on the Polynesian island of Rapa Nui (Easter Island). Five of these species are new to science and apparently endemic to the island: Coecobrya aitorererere n. sp., Cyphoderus manuneru n. sp., Entomobrya manuhoko n. sp., Pseudosinella hahoteana n. sp. and Seira manukio n. sp. The Hawaiian species Lepidocyrtus olena Christiansen & Bellinger and the cosmopolitan species Folsomia candida Willem also were collected from one or more caves. Coecobrya kennethi Jordana & Baquero, recently described from Rapa Nui and identified as endemic, was collected in sympatric association with C. aitorererere n.sp. With the exception of F. candida, all species are endemic to Rapa Nui or greater Polynesia and appear to be restricted to the cave environment on Rapa Nui. A key is provided to separate Collembola species reported from Rapa Nui. We provide recommendations to aid in the conservation and management of these new Collembola, as well as the other presumed cave-restricted arthropods.

Revision of Vesiculentomon, Nosekientomon n. g. (Protura: Acerentomidae, Nipponentominae), and a Key to Genera of Nipponentominae

ABSTRACT Based on recent reexamination of types, Vesiculentomon ruseki Nosek, 1977, differs significantly from Vesiculentomon marshalli Rusek, 1974, in composition and shape of maxillary gland, number of anterior setae on metanotum, and shape of foretarsal sensillum t1. A new genus Nosekientomon is erected for V. ruseki. Nosekientomon n. gen. is characterized by three pairs of anterior setae on the metanotum, claviform foretarsal sensillum t1, and a smooth globular vesicle on the calyx of the maxillary gland. Vesiculentomon Rusek has four pairs of anterior setae on the metanotum, baculiform foretarsal sensillum t1, and a large vesicle near the calyx with dense granulation along its narrow proximal part. The original descriptions are corrected and supplemented with new characters, including head chaetotaxy, setal lengths, and porotaxy. A key to world genera of Nipponentominae is provided.

First Record of Millipeds as Hosts for Horsehair Worms (Nematomorpha) in North America

Abstract We report several cases in which Gordionus lineatus (Horsehair Worm) (Nematomorpha) parasitizes the diplopod Cambala annulata (Myriapoda, Diplopoda) in Ohio. Diplopods as host for nematomorphs in North America have previously only briefly been mentioned. This report is the first host record for a Nearctic Gordionus species. Gordionus lineatus is also a new record for Ohio. Though the sample size is small, the prevalence may be high (50%). Myriapods appear to survive the parasitization. As Cambala annulata is likely to be herbivorous, pathways of infection with nematomorphs are discussed.

Redefinition and Four New Species of Yavanna Szeptycki and Comparison with Nosekiella Rusek (Protura: Acerentomidae: Nipponentominae)

ABSTRACT Generic redefinitions of Yavanna Szeptycki and Nosekiella Rusek based on type species are presented. Four new species of Yavanna are described: Yavanna baikalica n. sp., Yavanna chimitovae n. sp., Yavanna babenkoi n. sp., and Yavanna stebaevae n. sp. from Siberia. Nosekiella danica (Tuxen) is redescribed, and Nosekiella behanae Nosek and Nosekiella sinensis Bu & Yin are transferred to Yavanna. A key to the Nosekiella group of genera is provided, as well as a key to the known Yavanna spp.

Biodiversity Explosion: Collembola (Springtails) of Great Smoky Mountains National Park

Abstract Collembola are the most abundant hexapods, sometimes numbering 50,000 individuals/m2 in temperate deciduous forest. Prior to the All Taxa Biodiversity Inventory, 55 species had been reported from Great Smoky Mountains National Park (GSMNP), some of which were misidentifications. Currently, more than 200 species are recognized in GSMNP, including at least 60 species new to science and more than 100 new records. In addition, reexamination of type specimens in collections dating to the 1940s has validated a number of species that had been synonymized with other taxa, such as in the genus Morulina. One new genus has been collected, and three new species belonging to previously non-North American genera have been found (two South American, one Mediterranean). Several new records are major range extensions, such as Folsomia fimetaria, known previously from the Canadian Maritime provinces, and Hypogastrura tooliki, described from Alaska. Digital imaging and videography of live springtails is being used to more accurately render appearance and coloration and to document behaviors and interactions with other soil and litter biota. Molecular differentiation of Tomoceridae is underway in order to more reliably separate the many similar species of this common family. A Lucid-based online key for identification of southern Appalachian Collembola is under construction; where possible, this key will use characters visible with a dissecting microscope to distinguish species.