Corresponding author: Anatoly B. Babenko (
Academic editor: L. Deharveng
The paper is devoted to a taxonomic review of
Babenko AB, Fjellberg A (2015) Subdivision of the tribe Oligaphorurini in the light of new and lesser known species from North-East Russia (Collembola, Onychiuridae, Onychiurinae). ZooKeys 488: 47–75. doi:
Two undescribed species of the tribe
Recently
Main diagnostic characters used for genus separation in
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Apical vesicle on |
present | absent | |||
Tibiotarsal setae | clavate | pointed | ||||
Anal spines | present | absent | present | |||
Furcal rudiment | finely granulated area | small pocket or finely granulated area | finely granulated area, sometimes with a kind of pocket | cuticular fold or deep pocket | finely granulated area | |
Dental setae | four in line | four in two rows | two in line | four in two rows | four in line | |
Manubrial setae | one row | two rows | two rows | two (seldom one) rows | one row | |
Unpaired setae on |
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Species involved |
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Anal spines | absent | present | |||
Setae on |
2+2 setulae + 2+2 setae | 1+1 setulae + 1+1 setae | 2+2 setulae + 2+2 setae | |||
Species involved |
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in subapical position | normal | “ |
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Anal spines | absent | present or (rarely) absent | ||||
Distal tibiotarsal setae | 11 | 11 or fewer | ||||
Furcal rudiment | cuticular furrow or finely granulated area | |||||
Dental setae | two or four in one row | four in two rows | ||||
Manubrial setae | number of rows varied | |||||
fused | separated | |||||
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Anal spines | present | present or absent | |||
Distal tibiotarsal setae | 11 | 11 | 5–11 | |||
Furcal rudiment | cuticular furrow | cuticular fold | finely granulated area | |||
Dental setae | 1+1 | 2+2 | absent | |||
2 (at a level with dental setae) | 2 (at a level with posterior row of dental setae) | 2–4 | ||||
4–6 | 3–6 | 2 | ||||
4–5 | 4–7 | 4–6 |
In 2014 a complete revision of the genus
Holotype ♂, Russia, Magadan District, upper reaches of Kolyma River, Bolshoi Annachag Mt. Range, field station “Aborigen” [
Paratypes 6♂, 5 ♀, and 4 juveniles, same data as holotype (MSPU); 1♂, 2 ♀, and 1 juveniles, same data but moss, lichens on rock, 1650 m alt., 23 vii 1979, A. Fjellberg leg. (MSPU).
Colour white. Size of adults 0.73–0.92 mm. Body slender and elongated,
Pseudocellar formulas (
This new species resembles two congeners recently described from the European part of Russia, namely
The presence of only four papillae in
The name reflects the uncertain generic position of the new species.
Known only from the type locality, the alpine belt in the upper reaches of Kolyma river.
Holotype ♂, Russia, Magadan District, upper reaches of Kolyma River, Bolshoi Annachag Mt. Range, field station “Aborigen” [
Paratypes 1♂, 1♀, and 1 juvenile, same data as holotype (MSPU).
Colour white. Size of adults 1.2–1.3 mm. Body slender and elongated. Antennae slightly shorter than head, club-like with
Pseudocellar formulas (
Several uncommon features, like 2+2 pseudocelli and few setae on
The only known species of the tribe with
Named after the presence of 2+2
Known only from the type locality.
Juveniles from Magadan (NE Russia) have a furcal field with 2+2 setae behind the cuticular furrow, followed by 3+3
holotype, ♂, “USSR, Chukotka, Chaun Bay [
15 specimens, Russia, Novosibirsk Islands, Kotel’nyi, Balyktakh river [
Colour white. Size 0.8–0.9 mm. Body shape cylindrical. Antennae about as long as head,
Pseudocellar formula (
Originally described as
Chaetotaxy of abdominal sterna.
In the interactive key on
Five known species of the tribe possess the same number of dorsal and ventral pseudocelli as
The presence of 7 long guard setae of labium in such small species as
holotype, ♀, “ USSR, Magadan Reg., Aborigen [field station,
1 ♂, Magadan District, Bolshoi Annachag Mts. Range, upper reaches of Kolyma River, field station “Aborigen”, valley bottom near station, moss and litter of
Colour white. Size 0.8-0.9 mm. Body shape cylindrical. Antennae about as long as head,
Pseudocellar formula (
The redescription completely matches the original one, although
The set of dorsal pseudocelli displayed by
holotype, ♀, “USSR, Magadan Reg., “Death Valley”, Magadan-Ust’ Umchug [road], 209 km from Magadan, moss, lichen,
1 specimen, Magadan District, Bolshoi Annachag Mts. Range, upper reaches of Kolyma River, field station “Aborigen” [
Colour white. Size 0.75 mm. Body shape cylindrical. Antennae about as long as head,
Most common dorsal pseudocellar formula (
The number of pseudocelli in the species appears to be more variable than stated in the original description by
The presence of ventral setae on
Only one other known species of the tribe shares the absence of
The species listed as
Unfortunately, this parthenogenetic form is not the only one present in the northern areas of the Palaearctic. On Taimyr Peninsula and Novosibirsk Islands another bisexual form was found. Probably the same (or similar) form exists in southern Norway (
Contrary to
holotype, ♀, “USSR, Magadan Reg., Aborigen [
Unfortunately the types of the species were partly damaged and no additional specimens were found in the available material from the vicinity of Aborigen field station. So, only few additional details can be added to the original description.
Labium with thick terminal seta only on papilla
Chaetotaxy of abdominal sterna.
The species is well defined due to the absence of sublobal setae on the maxillary outer lobe (a unique character for the tribe or even for
holotype, ♂, “Alaska, Prudhoe Bay,
50 specimens, Russia, Yakutia (Sakha Republic), Suntar-Khayata Mt. Range, upper reaches of Kyubyume River [
Colour white. Granulation distinctly enlarged on
Pseudocellar formula (
The above redescription is in full accordance with the original one, adding a few details. While originally described from Alaska,
The morphological characters being widely accepted as separating genera of
On the
In summary,
This adequate but probably too simplified scheme was neglected by
The recent revision of the Palaearctic species of
In fact the diversity of manubrial chaetotaxy patterns in
Chaetotaxy of abdominal sterna.
Chaetotaxy of abdominal sterna.
Chaetotaxy of abdominal sterna.
The present generic framework for
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2 | Only |
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7 | Only |
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9 | Anal spines present. Upper subcoxae with 1-1-1 |
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– | Anal spines absent. Upper subcoxae with 2-(2)3-3 |
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11 | Maxillary outer lobe without sublobals. Formula of dorsal |
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– | Maxillary outer lobe with 2 sublobals. Formula of dorsal |
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12 | Labium of |
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We express our sincere thanks to V. Behan-Pelletier, M. Potapov, O. Makarova, I. Kaprus’ and Yu. Shvejonkova for the loan of valuable material and for their constructive comments. We are also much indebted to anonymous reviewers and the academic editor, Louis Deharveng, for critical and suggestive remarks.
The paper has been supported through grants of the Russian Foundation for Basic Research (projects 11-04-00175 and 14-04-01114) and through several scientific programmes of the Russian Academy of Sciences.