Rab
Rabidosa Roewer, 1960
- Rabidosa carrana (Bryant, 1934)
- Rabidosa hentzi (Banks, 1904)
- Rabidosa punctulata (Hentz, 1844)
- Rabidosa rabida (Walckenaer, 1837)
- Rabidosa santrita (Chamberlin & Ivie, 1942)
Arachnida → Araneae → Lycosidae
Rac
Racata Millidge, 1995
- Racata grata Millidge, 1995
Arachnida → Araneae → Linyphiidae , Rachias
Rad
, Radfordia
Radulphius Keyserling, 1891
- Radulphius barueri Bonaldo & Buckup, 1995
- Radulphius bicolor Keyserling, 1891
- Radulphius bidentatus Bonaldo & Buckup, 1995
- Radulphius boraceia Bonaldo & Buckup, 1995
- Radulphius caldas Bonaldo & Buckup, 1995
- Radulphius camacan Bonaldo, 1994
- Radulphius cambara Bonaldo & Buckup, 1995
- Radulphius caparao Bonaldo & Buckup, 1995
- Radulphius lane Bonaldo & Buckup, 1995
- Radulphius laticeps Keyserling, 1891
- Radulphius latus Bonaldo & Buckup, 1995
- Radulphius monticola (Roewer, 1951)
- Radulphius petropolis Bonaldo & Buckup, 1995
- Radulphius pintodarochai Bonaldo & Buckup, 1995
- Radulphius singularis Bonaldo & Buckup, 1995
- Radulphius strandi Caporiacco, 1947
Arachnida → Araneae → Eutichuridae
Rae
, Raecius
Raf
, Rafalus
Rak
, Rakaia
Ral
, Rallinyssus
Ram
, Ramaculus , Ramogneta , Ramonoppia , Ramsayella , Ramsayellus , Ramuloppia , Ramusella , Ramuselloppia
Ran
Rangitata Forster & Wilton, 1973
- Rangitata peelensis Forster & Wilton, 1973
Arachnida → Araneae → Amphinectidae , Ranops
Ransonia Blandin, 1979
- Ransonia mahasoana Blandin, 1979
Arachnida → Araneae → Pisauridae
Rao
, Raoiella , Raoiellana
Rap
Rapua Forster, 1970
- Rapua australis Forster, 1970
Rar
, Rarahu
Ras
, Rastellobata
Rastellus Platnick & Griffin, 1990
- Rastellus africanus Platnick & Griffin, 1990
- Rastellus deserticola Haddad, 2003
- Rastellus florisbad Platnick & Griffin, 1990
- Rastellus kariba Platnick & Griffin, 1990
- Rastellus narubis Platnick & Griffin, 1990
- Rastellus sabulosus Platnick & Griffin, 1990
- Rastellus struthio Platnick & Griffin, 1990
Arachnida → Araneae → Ammoxenidae
Rav
, Raveniella , Raveniola , Ravilops
Ray
, Rayforstia