Identification and character analysis of the Acerentomidae (Protura) of the northeastern Palearctic (Protura: Acerentomidae) Shrubovych, Julia Zootaxa 2014 3755 2 136 164 [240,339,152,178] Entognatha Animalia Protura 14 150 Arthropoda order    1 Spiracles present on mesonotum and metanotum............................................... (Eosentomata) ...2  - Spiracles absent … (Acerentomata)....................................................................... 3   2 Pseudoculus with three round granules, tergites VII and VIII with 6 A-setae....................  Eosentomon tshergense  - Pseudoculus without inner structures, tergite VII with 8 A-setae, tergite VIII with 4 A-setae.............  Eosentomon asahi   3 Abdominal appendages I–III two-segmented ( Hesperentomidae)..........................  Hesperentomon martynovae  - Abdominal appendages I–II or only I two-segmented........................................................ 4   4 Second pair of abdominal legs two-segmented ( Protentomidae).............................  Proturentomon stebaevae  - Second pair of abdominal legs one-segmented ( Acerentomidae)................................................ 5   5 Striate band reduced, striae indistinct or absent.............................................................. 6  - Striate band well developed, striae distinct................................................................. 10   6 Labial palpi reduced to sensillum and three setae.............................................. (  Baculentulus) … 7  - Labial palpi well developed with terminal tuft of setae and a sensillum........................  Tuxenentulus solncevae   7 Tergite VIII with 16 posterior setae, head seta d6present....................................  Baculentulus potapovi  - Tergite VIII with 15 posterior setae, head seta d6absent...................................................... 8   8 Tergite VII with 4 pairs of A-setae, with P1aand P3asetae present, sternite VIII with 6 setae........  Baculentulus borealis  - Tergite VII with 3 pairs of A-setae, with P1aand P3asetae absent, sternite VIII with 4 setae........................ 9   9 Sternite I with 4 P-setae, sternite XI with 6 setae.........................................  Baculentulus loxoglenus  - Sternite I with 2 P-setae, sternite XI with 4 setae..........................................  Baculentulus pomorskii   10 Mesonotum and metanotum with 2 pairs of A-setae...........................................  Sugaentulus andrzeji  - Mesonotum and metanotum with 3 or 4 pairs of A-setae...................................................... 11   11 Mesonotum and metanotum with 3 pairs of A-setae......................................................... 12  - Mesonotum with 3 pairs of A-setae, metanotum with 4 pairs of A-setae......................................... 25   12 Foretarsal sensillum t1filiform......................................................................... 13  - Foretarsal sensillum t1claviform............................................................ (  Yavanna) … 21   13 Pronotum with 3 pairs of setae, calyx of maxillary gland heart-shaped, with strong papillae on large appendices.............................................................................................  Callientomon chinensis  - Pronotum with 2 pairs of setae, calyx of maxillary gland with or without appendices, papillae on appendices absent...... 14   14 Calyx of maxillary gland small and weakly granulated, foretarsal sensillum t3globular..................  Nienna parvula  - Calyx of maxillary gland large, heart-shaped and strongly granulated, foretarsal sensillum t3leaf-shaped............... 15   15 Foretarsal seta β1sensilliform; membranal pores on segments II–VI present.......................  Noldo submontanus  - Foretarsal seta β1setiform, membranal pores on segments II–VI absent (  Verrucoentomon).......................... 16   16 Mesonotum and metanotum with P2a’setae, sternites IV–VI with 5 A-setae.................................... 17  - Mesonotum and metanotum without P2a’setae, sternites IV–VI with 3 A-setae.................................. 18   17 Tergite I with 16 P-setae (seta P3a’present), foretarsal sensilla cand ebroad...................  Verrucoentomon aurifer  - Tergite I with 14 P-setae (seta P3a’absent), foretarsal sensilla cand eslender....................  Verrucoentomon joanis   18 Tergites I–VI with seta P1a, comb with straight hind margin................................................. 19  - Tergites I–VI without seta P1a, comb with concave hind margin...........................  Verrucoentomon louisanne   19 Sternite I with 2 P-setae, sternite III with 5 P-setae.....................................  Verrucoentomon kawakatsui  - Sternite I with 4 P-setae, sternite III with 6 P-setae......................................................... 20   20 Sternite VII with seta Pc, accessory setae on tergites I–VI long, setiform, head seta d6absent....  Verrucoentomon shirampa  - Sternite VII without seta Pc, accessory setae on tergites I–VI short, sensilliform, head seta d6presen.....................................................................................................  Verrucoentomon anatoli   21 Seta P1apresent on tergites I–VII, M2present on prosternum, sternite III with 6 P-setae, head seta d6present........... 22  - Seta P1aabsent on tergites I–VI, M2absent on prosternum, sternite III with 5 P-setae, head seta d6absent............. 23   22 Mesonotal setae P1aand P2aof distinctly different lengths, with P2avery short; P4on metanotum reduced, shorter than P3a; head setae d7and sd7equal in length, pronotal seta 1about four times longer than seta 2............. Yavanna chimitovae  - Mesonotal setae P1aand P2aof equal length, P4on metanotum longer than P3a,head seta d7longer than seta sd7,pronotal seta 1twice the length of seta 2............................................................  Yavanna baikalica   23 Foretarsal sensilla band cnearly the same length, sensilla band a’thin......................................... 24  - Foretarsal sensillum babout twice the length of c, sensilla band a’thickened.........................  Yavanna altaica   24 Sternite VII with seta Pc, foretarsal sensilla a, band c’about the same length, foretarsal seta δ4setiform.  Yavanna stebaevae  - Sternite VII without seta Pc, foretarsal sensilla aand c’clearly longer than b,foretarsal seta δ4thick and blunt..................................................................................................  Yavanna babenkoi   25 Foretarsal sensillum t1baculiform (  Yamatentomon)......................................................... 26  - Foretarsal sensillum t1filiform........................................................................ 27   26 Tergite VII with seta A4’, prosternum with seta M2......................................... Yamatentomon yamato  - Tergite VII lacking seta A4’,prosternum without seta M2.................................  Yamatentomon kunnephupi   27 Calyx of maxillary gland small, metanotum without seta A1but with seta A5(  Filientomon)........................ 28  - Calyx of maxillary large, heart-shaped with distinct granulation, metanotum with seta A1, without seta A5(  Nipponentomon,  Imadateiella)....................................................................................... 29   28 Seta A1’present on tergites I–VI, A4’present on tergite VII, P3apresent on tergites II–VI, head seta d6absent........................................................................................  Filientomon duodecimsetosum  - Seta A1’absent on tergites I–VI, A4’absent on tergite VII, P3aabsent on tergites II–VI, head seta d6present.................................................................................................  Filientomon sibiricum   29 Mesonotum and metanotum with P2a’setae............................................................... 30   -Mesonotum and metanotum without P2a’setae........................................................... 31   30 Tergite I with seta P0a, tergite VII with P1aseta, sternite VII with seta Pc, sternite VIII with 6 setae, pores salabsent.........................................................................................  Nipponentomon taiga   -Tergite I without seta P0a, tergite VII without P1aseta, sternite VII without seta Pc, sternite VIII with 4 setae, pores salpres- ent on sternites II–VII...................................................................  Imadateiella murka   31 Tergite VI with seta P1a............................................................................... 32  - Tergite VI without seta P1a............................................................  Nipponentomon jaceki   32 Tergite VII with seta P1a............................................................................. 33  - Tergite VII without seta P1a..................................................  Nipponentomon khabarovskense   33 Labrum protruded, sternites I–III with 5 A-setae, sternite III with 5 P-setae......................  Nipponentomon nippon  - Labrum not protruded, sternites I–III with 3 A-setae, sternite III with 6 P-setae.................................. 34   34 Sternite VII with 5 A-setae, sternite VI without seta Pc, claw with two inner teeth.............  Nipponentomon bidentatum  - Sternite VII with 3 A-setae, sternite VI with seta Pc, claw with one inner tooth.....................  Imadateiella sharovi