Checklist of the Collembola: Key to the species of the caecus group of Arrhopalites |
This key is still under construction. Note that missing figures will be provided as soon as possible. Currently, the key is in the feasibility study phase to find out how to integrate in the checklist in a modular way a key that has been generated with DELTA.
Robert S. Vargovitsh,
Schmalhausen Institute of Zoology NAS of Ukraine, Kiev, 01601, Ukraine
Frans Janssens,
Department of Biology, University of Antwerp, Antwerp, B-2020, Belgium
1(0). Cuticular spines on sixth abdominal segment absent.......... 2 Cuticular spines on sixth abdominal segment present........ 10 2(1). Fourth antennal segment subdivided and adjoining subsegments separated by several rings................................ 3 Fourth antennal segment undivided or its adjoining subsegments separated by one ring..................................... 7 3(2). Antenna 2 times or more longer than head; tunica on third claw absent.................................................... 4 Antenna about 1.5x of head; tunica on third claw present...... ............................................... karabiensis 2 4(3). Claws extremely long........................................ 5 Claws not extremely long.................................... 6 5(4). Seta ms5 on sixth abdominal segment absent; setae of head dorsum slender; antenna about 2 times of head...... macronyx Seta ms5 on sixth abdominal segment present; setae of head dorsum stout; antenna about 3x of head.................. gul 6(4). Circumanal setae broadened and mps3 present; fourth antennal segment with 13 whorls of setae; head dorsum with 9 spine-like setae; third antennal segment with subbasal swelling......................................... abchasicus 1 Circumanal setae not broadened and mps3 absent; fourth antennal segment with 15 whorls of setae; head dorsum with 5 spine-like setae; third antennal segment not swelled........ ................................................ peculiaris 7(2). Anterodistal seta of dens Ia not or weakly spine-like; fourth antennal segment undivided................................ 8 Anterodistal seta of dens Ia strongly spine-like; fourth antennal segment with 3-4 subsegments............. ulehlovae 8(7). Eyes 1 + 1.................................................. 9 Eyes absent........................................ pukouensis 9(8). Circumanal axial seta ms1 forked..................... coreanus Circumanal axial seta ms1 not forked.................... minor 10(1). Sixth abdominal segment with 5 + 5 cuticular spines. antrobius Sixth abdominal segment with at most 4 + 4 cuticular spines... ........................................................ 11 11(10). Fourth antennal segment subdivided and adjoining subsegments of fourth antennal segment separated by several rings.... 12 Fourth antennal segment undivided or its adjoining subsegments separated by one ring.................................... 13 12(11). Antenna 2 times of head; empodia not reaching tip of corresponding claw; hind claw without tunica; seta ms5 on sixth abdominal segment absent................... abchasicus Antenna about 1.5x of head; empodia overtopping tip of corresponding claw; hind claw with tunica; seta ms5 on sixth abdominal segment present....................... karabiensis 13(11). Sixth abdominal segment with 4 + 4 cuticular spines........ 14 Sixth abdominal segment with at most 3 + 3 cuticular spines... ........................................................ 17 14(13). Fourth antennal segment undivided or very indistinctly divided into pseudosubsegments................................... 15 Fourth antennal segment with 4 distinct ringed subsegments.... .................................................. incertus 15(14). Antenna 1.5x or less of head............................... 16 Antenna about 2 times of head......................... minutus 16(15). First claw with inner tooth............................ caecus First claw without inner tooth......................... millsi 17(13). Empodium of first legi with distinct corner tooth; sixth abdominal segment usually with 3 + 3 cuticular spines....... .................................................... tenuis Empodium of first legi without corner tooth; sixth abdominal segment with 2 + 2 cuticular spines.................. loczyi
Endnotes
1 Possession of cuticular spines on the sixth abdominal segment is variable in abchasicus.
2 Possession of cuticular spines on the sixth abdominal segment is variable in karabiensis.