Belongs within: Neopilionidae.
The Ballarrinae is a group of very small long-legged harvestmen found in Australia, southern Africa and South America. Ballarrines are characterised by the possession of elongate pedipalps with an extremely long patella, retroflexed tibia and reduced terminal claw on the tarsus. In the Australian genera Ballarra, Plesioballarra and Arrallaba, a barbed process is present on the left side of the penis at the junction between shaft and glans; such a process is absent in the South American Americovibone lanfrancoae (the male of the South African Vibone vetusta has not been described).
Characters (from Hunt & Cokendolpher 1991): Body small, usually greater than 0.8 and less than 3.5 mm long. Integument usually thin, at the most armed with minute setae. Abdominal spiracle usually concealed beneath coxa IV. Penis shaft usually with strong dorsal keel, muscle usually long (tendon short), left ventrolateral barbed process present or lacking. Ovipositor with two or four seminal receptacles. Pedipalp patella longer than tibia and usually tarsus, dorsal angle between patella and tibia less than 180°, patella and tibia without dense pile of setae; tarsus usually concave dorsad along its length, plumose setae extend to or almost to distal tip, non-socketed setae restricted to area of distal tip or lacking; tarsal claw lacking or small, usually inserted ventrodistally, usually with on ventral tooth. Chelicerae small in most species; first segment with or without ventral spur; jaws with continuous row of teeth of subequal size in most species. Legs long and usually slender; pseudoarticulations present in all metatarsi, tibia II, and femur II in some species; tarsi each with simple claw or claw with small teeth on each side. Sexual dimorphism slight in most species.
|--Vibone Kauri 1961 HC91
| `--*V. vetusta Kauri 1961 HC91
|--Plesioballarra Hunt & Cokendolpher 1991 HC91
| `--*P. crinis Hunt & Cokendolpher 1991 HC91
|--Arrallaba Hunt & Cokendolpher 1991 HC91
| `--*A. spheniscus Hunt & Cokendolpher 1991 HC91
|--Americovibone Hunt & Cokendolpher 1991 HC91
| `--*A. lanfrancoae Hunt & Cokendolpher 1991 HC91
`--Ballarra Hunt & Cokendolpher 1991 HC91
|--*B. drosera Hunt & Cokendolpher 1991 HC91
|--B. alpina Hunt & Cokendolpher 1991 HC91
|--B. cantrelli Hunt & Cokendolpher 1991 HC91
|--B. clancyi Hunt & Cokendolpher 1991 HC91
|--B. longipalpus Hunt & Cokendolpher 1991 HC91
`--B. molaris Hunt & Cokendolpher 1991 HC91
*Type species of generic name indicated
[HC91] Hunt, G. S., & J. C. Cokendolpher. 1991. Ballarrinae, a new subfamily of harvestmen from the Southern Hemisphere (Arachnida, Opiliones, Neopilionidae). Records of the Australian Museum 43: 131-169.