Taxonomic key to the subfamily Opilioninae
tribes Opilionini and Scleropilionini (Mizozatus Nakatsudi, 1937 not included)
[illustrations of each genus are found at: https:// opiliones .fandom.com/wiki/ Opilioninae (accessed 25 October 2020)]
1 Body integument coriaceous or heavily sclerotized; frontal margin of cephalothorax with a row of strong denticles; palpal femora with strong pointed tubercles.......................... 2 … tribe ... Scleropilionini Snegovaya et Staręga, 2008
- Body integument not very sclerotized; body oval in shape; frontal margin of cephalothorax with either a single or small group of denticles, palpal femora without strong tubercles........................................... 3 ... tribe Opilionini
2 Body is slender, flattened, especially the male opisthosoma strongly narrows posteriorly, not oviform; palpal femur with rows of long strong pointed tubercles, patella with long apophysis................... Redikorcevia Snegovaya & Staręga, 2008
- Body elongated, palpal femur dorsally and ventrally with many prominent tubercles, palpal patella without apophysis...................................................................................... Scleropilio Roewer, 1911
3 In the middle of frontal edge of cephalothorax are situated a group of 5 large teeth........... Bidentolophus Roewer, 1912
- Front section of cephalothorax with a group of medium-sized denticles; ocularium low.............................. 4
4 Legs short (femur I length does not exceed body length); 1st, sometimes 3rd pair of legs, are twice as thick as the 2nd and 4th............................................................................... Egaenus C.L. Koch, 1839
- Legs can be either short or long; 1st sometimes 3rd pair of legs are thicker than 2nd; 4th pairs less than twice as thick..... 5
5 Glans of the penis narrow throughout (about width of distal end of truncus), elongated, and slightly upward curved distally (lateral view).................................................................. Gricenkovia Snegovaya, 2018
-. Glans of the penis oval in length or banana-shaped (lateral view)................................................ 6
6 Truncus of the penis non-uniform in width, thickened basally (generally double or more the width of the truncus distally) and narrowed distally (in dorsal view).................................................... Homolophus Banks, 1893
- Truncus of the penis slenderer and uniform in width (in dorsal view)............................................. 7
7 Apical part of the penis with characteristic semicircular alae on the ventral side. Between the alae there is a horseshoe-shaped depression............................................................ Pamiropilio Staręga & Snegovaya, 2008
- Apical part of the penis without alae or horseshoe-shaped depression on the ventral side............................. 8
8 Truncus of the penis consisting of lateral incisions and dorsal or ventral depressions, no keel.......... Opilio Herbst, 1798
- Truncus of the penis extremely long, consisting of a subapical ventral keel accompanied by deep depressions...................................................................................... Himalphalangium Martens, 1973