taxonID	type	description	language	source
03E61F409350FFBB62C4FDE2DFEAFBB0.taxon	description	Among the species with a mucronal seta, A. bidenticulata may be recognised by few (fewer than 13) anterior setae on the ventral tube, a short, curved mucro, and pigmentation of the body usually not uniform (some segments darker than rest). Reproductive specimens lack modified setae. The species is common in damp Arctic tundra of the Holarctic region (Babenko & Fjellberg 2006) and is also frequent along streams and lakes in the Scandinavian mountains, in the highlands of Great Britain, and in continental Europe south to the Mediterranean area. In Asia the distribution of A. bidenticulata follows the Arctic coast, while the southern limit is unknown (Potapov 2001). In North American it is reliably recorded from Alaska and arctic Canada, but more southern populations probably represent other species.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBA62C4FF5FDE81FDF4.taxon	description	So far this species is known only from the Pacific Northwest region bordering the Juan de Fuca and Georgia Straits (Olympic National Park, Washington, and Garibaldi Provincial Park, British Columbia, respectively). It was collected from moss along mountain streams and waterfalls. The species is recognised by its markedly prognathous head (Fig. 3 A), abundant anterior setae on the ventral tube (more than 10 on each side), apical tooth of mucro much larger than subapical tooth (Fig. 6 B), slender claws, and normal, thin, setae on the body.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBA62C4FAC9DAE6F931.taxon	materials_examined	This species was originally described from glacial ice in Garibaldi Park, British Columbia. We have examined recent material from Alaska (Matanuska Glacier) and British Columbia (Overlord and Wedgemount Glaciers) (all collected by P. Hartzell). The species appears to be restricted to the glacial fauna, having adaptations such as extremely dark greenish black colour all over the body (Fig. 3 B) and short extremities. Also, the compact mucro with a small apical tooth is a trait generally present in winter Agrenia spp. and other Collembola associated with snow and ice.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBA62C4FDE2DA9BFC72.taxon	description	This species probably is widely distributed in the Rockies, with records from British Columbia, Idaho, Oregon, and Utah, living in wet moss along mountain streams. It is similar to A. agilis, but separated by head shape, which is normal and not prognathous, the stouter claws, and dense Isotomurus - like setal vestiture on the abdomen. Reproductive males may have short setae and a rugose cuticle on the thorax and anterior abdominal segments.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBE62C4F8A7D910FDC6.taxon	materials_examined	Type material. Holotype (in ethanol, not sexed) and 25 paratypes (ethanol) from USA, Tennessee, Sevier County, Great Smoky Mountains National Park, Rainbow Falls Trail, N 35 o 39.862 ', W 83 o 27.599 ', 06. VI. 2007, moss along stream, elevation 1,372 m, A. Fjellberg, sample number 0 7.188. Holotype and 15 paratypes deposited in the National Museum of Natural History, Washington, D. C.; remaining paratypes deposited in the University of Tennessee Entomology Collection. Additional material collected in late winter to early summer from Swain County, Great Smoky Mountains National Park, Noland Creek headwaters drift net samples, 20. I. 1993 to 11. V. 1993 (see Bernard & Felderhoff 2007), and from the banks of many other coldwater streams on the North Carolina side of Great Smoky Mountains National Park (Haywood County: Purchase Knob, Cataloochee River; Swain County: Clingman's Dome; Buncombe County: Elk Pasture Gap), as well as other North Carolina specimens from Graham County (several locations along Cherohala Skyway) and Yancey County (Mt. Mitchell State Park).	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBE62C4F8A7D910FDC6.taxon	description	Description. Size up to 2.1 mm. Colour olive, uniform, darkest on dorsal side. Legs, furca and sides of head paler. Antennae bluish red, paler towards base. No sharp mid-dorsal line on tergites. Specimens with pale ground colour usually with posterior edges of tergites narrowly darkened. Maxillae with short, unmodified lamellae densely packed with fine denticles; lamella 1 just passing tip of maxillary head. Large males with relatively longer antennae than females, up to 2.7 times length of head diagonal; in smaller individuals (juveniles) antennae about 1.5 times length of head diagonal. Sensilla of antennae normal, without particularly dense sensilla on the fourth segment. PAO oval, length about 1.3 times the diameter of nearest ocellus. Head shape in adults slightly prognathous (Fig. 2 A). Head and thorax with mixed short and long setae, remainder of body with short, fine setae. In reproductive males setae of Abd. V – VI distinctly shortened. Setae along frontoclypeal edge slightly longer and denser than the rest of the frontoclypeal area. Ventral tube with 0 – 6 anterior setae on each side (usually 4 or 5), lateral lobes with 10 – 20 setae on each side, caudal side with more than 35 setae in large individuals. Retinaculum with more than 25 setae in large specimens. Claws long and slender, particularly in animals collected in summer. Winter animals with relatively longer tunica at base of claws (Fig. 1 J): claw index 2.0 – 2.7 (winter), 2.8 – 4.5 (summer). Inner edge of unguis with small middle tooth. Mucro without lateral seta, in summer animals less curved and with larger apical tooth than in winter animals (Figs. 1 C, D). Subapical seta on dens strong, reaching well beyond tip of mucro. Ventral lamella of mucro moderately widened in the middle.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBE62C4F8A7D910FDC6.taxon	etymology	Etymology. Named for Dr. Charles Parker, U. S. Geological Survey, whose collection of hundreds of this species in Noland Creek headwater drift nets stimulated large-scale surveys for Collembola in Great Smoky Mountains National Park.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBE62C4F8A7D910FDC6.taxon	discussion	Discussion. Among species without a mucronal seta, A. parkeri n. sp. is recognized by the moderate number of anterior setae on the ventral tube (the two northern species A. atroviridis and A. riparia usually have no anterior setae, at most 1 – 2 in A. riparia), apical mucro tooth subequal to or smaller than subapical tooth (in A. agilis the apical tooth is much larger than the subapical tooth and body colour is not olive), and PAO longer than the diameter of the nearest ocellus (in A. cyanura the PAO is smaller, the ventral tube has more anterior setae, and colour is different). The cyclomorphic (winter / summer) change in shape of claws and mucro is similar to that described for A. riparia (Fjellberg 1986). The allometric growth in antennae and modified setae in reproductive males also are seen in A. polymorpha.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409351FFBE62C4F8A7D910FDC6.taxon	distribution	Distribution and ecology. Apparently widely distributed at higher elevations of the southern Appalachian Mountains (750 – 1,980 m) where it may be collected in great numbers in moss and debris along cold water streams. Highest numbers near the Noland Creek headwaters (~ 1,700 m elevation) were collected in drift-net samples in late winter and early spring when snow still covered the ground (Bernard & Felderhoff 2007, recorded as Agrenia sp.).	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409355FFBE62C4FD30D87DF8A4.taxon	materials_examined	Type material. Holotype: Unreproductive male (slide), USA, Washington, Whatcom County, Easton Glacier, N 48 o 44 ' 38 '', W 121 o 50 ' 0 1, on snow, 4. VIII. 2002, P. Hartzell, coll. Paratypes: One male and one female (on two slides) from the type locality, same data. All types deposited in the National Museum of Natural History, Washington, D. C. Additional material from USA collected by P. Hartzell: Two specimens from Lower Curtis Glacier, Whatcom Co., Washington, on snow, 1,600 m., 6. VIII. 2002; six specimens from Columbia Glacier, Snohomish Co., Washington, 1,600 m, 4. VIII. 2002; four specimens from Shoup Glacier, Alaska, and two specimens from Ptarmigan Glacier, Alaska, summer 2003.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409355FFBE62C4FD30D87DF8A4.taxon	description	Description. Size up to 3.5 mm. Colour uniform, dark brownish green. Antennae, legs and furca paler. Antennae long and slender, up to twice the length of head diagonal. Ventroapical and inner side of Ant. IV with dense short, erect sensilla (Fig. 6 D). Head distinctly prognathous, frontoclypeal setae not differentiated. PAO oval, slightly longer than diameter of nearest ocellus. Maxilla (Fig. 1 L) with lamella 1 reaching far beyond tip of capitulum, with a dense fringe of short cilia along the edges, otherwise covered with fine denticles; lamella 2 reaching tip of capitulum, with short cilia along ventral edge, otherwise with short denticles that are stronger than on other lamellae; lamella 3 small, situated at base of lamella 2, with only a few denticles; lamellae 4 – 6 densely covered with fine denticles. Body setal vestiture short and fine, macrochaetae only developed on inner side of femora and on tip of abdomen. Ventral tube in adults with 3 – 10 anterior setae on each side and more than 30 lateral and 40 caudal setae in large specimens. Retinaculum with more than 25 setae. Claws slender, unguis with distinct inner tooth in the middle (Fig. 1 J). Claw index 1.8 – 2.0. Mucro short and compact, apical and subapical teeth subequal, small basolateral tooth present (Figs. 1 A, B). Mucronal seta absent. Males present, sexual dimorphism not observed (no reproductive males seen).	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409355FFBE62C4FD30D87DF8A4.taxon	etymology	Etymology. The name reflects the extreme habitat and the unusual maxilla.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409355FFBE62C4FD30D87DF8A4.taxon	discussion	Discussion. This exceptionally large Agrenia is immediately recognised by the modified maxilla, in which lamella 1 is much longer than the capitulum. In other species lamella 1 either does not reach the capitulum tip, or only slightly bypasses it. Also, the presence of numerous short, erect sensilla on Ant. IV is unmatched by other species. All Agrenia spp. have these sensilla, but never as densely packed as in A. extrema.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409355FFBE62C4FD30D87DF8A4.taxon	distribution	Distribution and ecology. Alaska and Washington (see above). The remarkable habitat of this species (snow and icefields) and the long, delicate maxillary lamellae probably indicate a feeding habit based on sweeping organic particles from melt water on the glacial ice.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F40935AFFB362C4FF29DF3BFF2A.taxon	materials_examined	Type material. Holotype (ethanol) and 43 paratypes, USA, North Carolina, Roan Mountain, Powers Branch, Southern Appalachian Highlands Conservancy, seep, elevation 1,423 m, 14. VI. 2000, P. Jennings and A. Trently coll. Additional material examined: Two samples from USA, North Carolina, Haywood County, Great Smoky Mountains National Park, Purchase Knob, A. Fjellberg, coll., June 2007. Holotype and 25 paratypes deposited in the National Museum of Natural History, Washington, D. C.; remaining paratypes deposited in the University of Tennessee Entomology Collection.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F40935AFFB362C4FF29DF3BFF2A.taxon	description	Description. Size up to 1.4 mm, reproductive male 1.1 mm. Dorsal side of thorax and abdomen bluish or violet brown, usually pale (Fig. 5 A). Broad midsections of Th. II-III and Abd. V-VI generally darkest. Posterior edges of tergites narrowly darkened. Tergites without sharp middorsal line. Head very pale, almost white, dark pigment present only as a middrosal occipital spot behind the dark eye fields (Fig. 5 B). Area between eyes and antennal base diffusely darkened in large specimens. Mouth region and sides of head completely unpigmented. Head shape weakly prognathous (Fig. 2 B). Antennae violet blue, 1.7 – 2.0 times length of head diagonal. Legs light blue, furca unpigmented. Maxillae with short, unmodified lamellae, lamella 1 slightly bypassing tip of capitulum (Fig. 1 N). PAO oval, length about 1.4 times diameter of nearest ocellus. Setae on head and body short, thin, delicate, and sparse, of uniform length. Setae along frontoclypeal edge not differentiated. Ventral tube with 1 – 5 anterior setae on each side, 6 – 13 lateral setae, and more than 20 caudal setae. Retinaculum with 15 – 20 setae. Claws very slender, with small indistinct tooth at middle of inner edge; tunica short, claw index 3.0 – 3.9 (Fig. 1 H). Mucro slender, with apical and subapical teeth of similar size; basal tooth strong (Fig. 6 C); ventral edge straight, with broad lamella; mucronal seta absent; differentiated subapical seta on dens not reaching beyond tip of mucro (Figs. 1 E-F). Reproductive males with unmodified setae on tip of abdomen.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F40935AFFB362C4FF29DF3BFF2A.taxon	etymology	Etymology. The name reflects the thin, slender claws (falcula [L]: little sickle).	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F40935AFFB362C4FF29DF3BFF2A.taxon	discussion	Discussion. The small body size, elongate mucro without lateral seta, short subapical seta on dens, and very slender claws with small tunica differentiate this species from other Agrenia. The mucro is similar to that of A. lamellosa, but in that species the lateral seta is present (Fjellberg 1988). For separation from A. tarashchukae n. sp., see below. Only summer animals were seen. Winter samples may have specimens differing in characters of claws, mucro and antennae. If the samples are representative, this species is the smallest Agrenia known. In particular, a reproductive male of only 1.1 mm is unusual. These small adults have " juvenile " traits, e. g., relatively short antennae, few setae on ventral tube, pale colour, and short subapical seta on the dens. We have considered the possibility that A. falcula n. sp. may be small A. parkeri that will develop typical characters of the latter (e. g., long subapical seta on dens) after continued growth. The existence of different reproductive " morphs " appearing during continued growth was described in A. polymorpha (Fjellberg 1986). Although we have no clear evidence that A. falcula and A. parkeri are conspecific, the case should be examined with molecular methods or with longterm studies of field / laboratory populations.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F40935AFFB362C4FF29DF3BFF2A.taxon	distribution	Distribution and ecology. This species is known so far only from high elevations of the southern Appalachian Mountains, in damp moss along cold streams, seeps, and springs.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409358FFB362C4FE90DE81FAC0.taxon	materials_examined	Type material. Holotype: Female (slide) and 10 paratypes on 6 slides from USA, New York, Minnewaska State Park Preserve, Awosting Falls, moss in the spray zone, 27. V. 1996, M. Tarashchuk, coll. Holotype and 6 paratypes deposited in the National Museum of Natural History, Washington, D. C.; remaining paratypes deposited in the University of Tennessee Entomology Collection.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409358FFB362C4FE90DE81FAC0.taxon	description	Description. Largest specimen seen 1.7 mm. Precise colour not observed as only slide specimens were available, but appearing to have been of uniform colour without marked pattern. Head shape normal, not prognathous. Antennae 1.8 – 1.9 times the length of head diagonal. Maxilla unmodified, lamellae short. PAO oval, about as long as diameter of nearest ocellus. Setae on body dense, moderately stout, and short; those on head and thorax clearly differentiated into short and long setae. Frontoclypeal setae unmodified. Ventral tube with 2 – 4 anterior setae on each side, 12 – 24 lateral setae, and more than 35 caudal setae in large specimens. Retinaculum with more than 30 setae in large specimens. Differentiated subapical seta on dens short, not passing tip of mucro. Mucro elongate, with strong, undulating ventral and lateral lamellae (Fig. 1 G); apical and subapical teeth of mucro subequal; outer dorsal lamella high and prominent (Fig. 6 A). Mucronal seta absent. Claws normal, not elongated (Fig. 1 I). Claw index 1.9 – 2.3. Only non-reproductive females and juveniles seen.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409358FFB362C4FE90DE81FAC0.taxon	etymology	Etymology. Named after the collector, our colleague Dr. Marina Taraschchuk, Kiev.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409358FFB362C4FE90DE81FAC0.taxon	discussion	Discussion. The short subapical seta on the dens, which does not bypass the tip of the mucro, is a character shared only with A. falcula n. sp. From this species A. tarashchukae n. sp. differs by having more robust claws (claw index less than 2.5), stronger dorsal lamella on mucro, and coarser body setae. In some Agrenia spp. these characters may depend on season or reproductive stage of the individual, but the samples of A. falcula and A. tarashchukae were made in summer and reproductive males of the former species do not differ from unreproductive individuals.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
03E61F409358FFB362C4FE90DE81FAC0.taxon	distribution	Distribution and ecology. The single collection of this species was made from wet moss in the spray zone. The type locality is in the Shawanagunk Mountains, in the northeastern part of the Appalachian Range.	en	Fjellberg, Arne, Bernard, Ernest C. (2009): Review of Agrenia Börner, 1906 with descriptions of four new species from North America (Collembola, Isotomidae). Zootaxa 2306: 17-28, DOI: 10.5281/zenodo.275389
