Pseudachorutes parvulus Börner, 1901

Kaprus’, Ighor J. & Weiner, Wanda M., 2009, The genus Pseudachorutes Tullberg, 1871 (Collembola, Neanuridae) in the Ukraine with descriptions of new species, Zootaxa 2166, pp. 1-23 : 13-15

Pseudachorutes parvulus Börner, 1901

Figs 52, 54 a, b, c, 56, 61a, b, 62, 77

Redescription. Body length without antennae 0.45–1.30 mm. Colour in alcohol bluish-grey, ocular plate bluish-black. Tegumental granulation fine, dense and uniform.

Antennae shorter than head. Ant. I with 7 setae, Ant. II with 12 setae and Ant. III with 18–19 ordinary setae. Ant. III and IV fused dorsally, ventral separation well marked. Sensory organ of Ant. III consisting of: two small, globular internal sensilla, two subcylindrical guard sensilla (ventral sensillum longer 1.15 times than dorsal one) and two guard setae between them; ventral microsensillum present. Ant. IV with about fifty ordinary setae and six distinct subcylindrical sensilla; dorsoexternal microsensillum and subapical organite present; apical vesicle simple, slightly or strongly trilobed ( Figs 56, 54 a, b, c).

PAO with 6–9 vesicles, 1.3–1.8 times larger than ocellus B. 8+8 eyes. Buccal cone elongated. Mandible with four teeth (medial tooth small, subapical tooth bigger than medial one), styliform maxilla with two lamellae, one of them hooked ( Figs 61 a, b, 62). Labral formula: 2/2,3,3,4 ( Fig. 77 ). Labium with 2+2 small organites x and small papillate seta L, with 12+12 ordinary setae (as in Fig. 27 ). Perilabial area with 5+5 subequal setae.

Dorsal chaetotaxy as in Fig. 52 , with mesosetae and longer sensory setae s. Formula per half tergum as: 022/11111. Microsensilla on Th. II present. Head with unpaired seta d1 and without a0 seta. Chaetae sd2 on the head level with or somewhat posterior to d2 chaetae. Th. I with 3+3 setae. Th. II with 11+11 setae (setae a2 present and a5, m4 absent) and Th. III with 10+10 setae (setae a2, a5 and m4 absent). Abd. I–III with 8+8 setae (m- row and a3 setae absent), Abd. IV with 9+9 setae (m-row setae absent), seta s = p5. Abd. V with a2 and without p2 setae, seta s = p3.

Ventral chaetotaxy: thoracic sterna without setae, VT with 4+4 setae, Abds. I without setae, Abds. II with 4+4 setae, Abds. III with 6–7+6–7 setae.

Dens with six setae. Mucro slightly hooked with broad lateral lamella. Manubrium with 13+13 setae. Tenaculum with 3+3 teeth. Each anal valve with two setae hr.

Tibiotarsi I, II and III with 19, 19 and 18 setae, respectively, seta B7 absent on tibiotarsus III. Femora I, II and III with 13, 12 and 11 setae, trochanters I, II and III with 6, 6 and 5-6 setae, coxae I, II and III with 3, 6–7 and 7–8 setae, subcoxae 2 of legs I, II and III with 0, 2 and 2 setae, subcoxae 1 of legs I, II and III with 1, 2 and 2 setae, respectively. Claw with small inner tooth and without lateral teeth. Empodial appendage absent.

Material examined. 3 females, 2 males (on slides), Ukraine, Ivano-Frankivs’k district, Karpats’ky National Park, near Vorochta village, Chornohora ridge, Pozhyzhevska Mt., 1500 m alt., Duschekia viridis and Pinus mugo crooked forest, leaf litter, 27.VI.1991, leg. I. Kaprus’; 2 males and 2 females (on slides), Ukraine, Ivano-Frankivs’k district, near Mykulychyn village, Gorgany ridge, 900 m alt., Fagus and Abies forest, leaf litter and moss, 25.VI.1991, leg. I. Kaprus’; 8 males and 10 females (on slides), Ukraine, L’viv district, near Skole town, Skolivs’ki Beskydy ridge, 1000 m alt., Fagus crooked forest, leaf litter and soil, 24.V.1990, leg. I. Kaprus’; 1 male and 3 females (on slides), Ukraine, Chernivtsi district, near Perkalab village, Chyvchyny ridge, Gnatasia Mt., 1500 m alt., Picea abies forest, leaf litter and moss, 14.VIII.1990, leg. I. Kaprus’; 3 males and 5 females (on slides), Ukraine, Zakarpattya district, near Mukacheve town, Quercus forest, leaf litter, 18.IV.2005, leg. J. Tsalan; 4 males and 2 females (on slides), Ukraine, L’viv district, Acer forest, leaf litter and soil, 27.X.1999, leg. I. Kaprus’; 5 males and 3 females (on slides), Ukraine, L’viv district, near Ivano-Frankove village, Roztochchya Hills, Fagus-Pinus forest, leaf litter and soil, 27.X.1999, near Mykolaiv town, leg. I. Kaprus’; 1 male and 1 female (on slides), Ukraine, Volyn’ district, near Volodymyr-Volyn’s’k town, Carpinus-Quercus forest, leaf litter and soil, 25.VII.2004, leg. I. Kaprus’; 2 males and 3 females (on slides), Ukraine, Zhytomyr town, Pinus-Quercus forest, leaf litter and soil, 5.II.2008, leg. I. Kaprus’; 8 males and 10 females (on slides), Ukraine, Kchmelnytsk district, Stara Ushycia village, xerothermic meadow, soil, 30.V.1997, leg. I. Kaprus’; 1 female (on slide), Ukraine, near Chernivtsi town, nests of birds, 16.V.2006, leg. V. Meleshchuk; 1 male and 1 female (on slides), Ukraine, Kirovograd district, Golovanivsk village, Quercus forest, leaf litter and soil, 30.V.1997, leg. I. Kaprus’; 5 males and 8 females (on slides), Ukraine, Crimea, near Jalta town, Martyan Reserve, Pinus-Quercus forest, 1200m alt., soil and leaf litter, 12.IX.1997, leg. I. Kaprus’; 4 males and 6 females (on slides), Ukraine, Crimea, near Shchebetovka village, Karadag Reserve, Fagus-Quercus forest, 700m alt., soil and leaf litter, 27.VI.1994, leg. M. Potapov.

Biology. Pseudachorutes parvulus has been collected in the forest litter, mosses, lichens and under bark. Bisexual corticole species.

Remarks. Recent morphological descriptions of P. parvulus were published by Jordana et al. (1997) and Fjellberg (1998). Morphological characters of the Ukrainian specimens fit these descriptions. Pseudachorutes parvulus resembles Pseudachorutes subcrassus Tullberg, 1871 , but differs in shape of mandible, in number of prelabral setae, in detail of chaetotaxy on Ant. IV and interocular area and also ratio PAO/ocellus B (see descriptions of P. parvulus and P. subcrassus ).

Figures

FIGURES 52 – 64. Pseudachorutes parvulus Börner, 1901. 52, dorsal chaetotaxy of body; 54 a, apical vesicle simple; 54 b, apical vesicle slightly trilobed; 54 c, apical vesicle strongly trilobed; 56, Ant. III and IV ventrally; 61 a, b, variants of mandibles; 62, maxilla; Pseudachorutes subcrassus Tullberg, 1871. 53, chaetotaxy of interocular area; 59, mandible; 60, Ant. III and IV ventrally; Pseudachorutes corticicolus (Schäffer, 1896). 55, right part of labium; 57, mandible; 58, maxilla; 63, distal part of leg III; 64, chaetotaxy of Abd. V and VI.

FIGURES 76 – 84. Shape and chaetotaxy of labrum: 76, Pseudachorutes corticicolus (Schäffer, 1896); 77, Pseudachorutes parvulus Börner, 1901; 78, Pseudachorutes subcrassus Tullberg, 1871; 79, Pseudachorutes pratensis Rusek, 1973; 80, Pseudachorutes scythicus sp. nov.; 81, Pseudachorutes janstachi sp. nov.; 82, Pseudachorutes palmiensis Börner, 1903; 83, Pseudachorutes vasylii sp. nov.; 84, Pseudachorutes vitalii sp. nov.

FIGURES 22 – 31. Pseudachorutes vasylii sp. nov. 22, dorsal chaetotaxy of body; 23, Ant. III and IV ventrally; 24, Ant. III and IV dorsally; 25, mandible; 26, maxilla; 27, labial chaetotaxy; 28, PAO and eyes; 29, distal part of leg III; 30, furca; 31, chaetotaxy of Abds. I – VI.