Ricinulei

Belongs within: Euchelicerata.

The Ricinulei are a group of arachnids found primarily in tropical rainforests. Members of this group are characterised by a pre-carapaceal structure (the cucullus), modified pedipalps and a characteristic mode of sperm transfer facilitated by an elaborate copulatory apparatus on the third leg of the male (Harvey 2002). Living exemplars are all included in the family Ricinoididae with Carboniferous fossil representatives separated as the Palaeoricinulei (Harvey 2002).

<==Ricinulei
    |--PalaeoricinuleiH02
    |    |--PoliocheridaeH02
    |    |    |--Terpsicroton Selden 1992V-MF13
    |    |    |    `--T. alticeps (Pocock 1911)S93
    |    |    `--Poliochera Scudder 1884V-MF13
    |    |         |--P. glabra Petrunkevitch 1913S93
    |    |         `--P. punctulata Scudder 1886F04
    |    `--CurculioididaeH02
    |         |--Amarixys Selden 1992V-MF13
    |         |    |--A. gracilis (Petrunkevitch 1945)S93
    |         |    `--A. sulcata (Melander 1903)S93
    |         `--Curculioides Buckland 1837V-MF13
    |              |--C. adompha Brauckmann 1987S93
    |              |--C. ansticii Buckland 1837H02
    |              `--C. scaber (Scudder 1890)S93
    `--Ricinoididae [Cryptostemmatidae, Cryptostemmatoidae, Neoricinulei]B-TP08
         |--CryptostemmaH02
         |    |--C. crassipalpe Hansen & Sørensen 1904HS04
         |    `--C. westermannii Guérin-Méneville 1838H02
         |--Ricinoides Ewing 1929B-TP08
         |    |--R. afzeliiH95
         |    |--R. atewaSF15
         |    `--R. hanseniA99
         |--Pseudocellus Platnick 1980B-TP08
         |    |--*P. dorotheae (Gertsch & Mulaik 1939)V-MF13
         |    |--P. bolivari (Gertsch 1971)V-MF13
         |    |--P. boneti (Bolivar & Pieltain 1942)V-MF13
         |    |--P. chankin Valdez-Mondragón & Francke 2011V-MF13
         |    |--P. cruzlopezi Valdez-Mondragón & Francke 2013V-MF13
         |    |--P. gertschi (Márquez & Conconi 1974)V-MF13
         |    |--P. jarocho Valdez-Mondragón & Francke 2011V-MF13
         |    |--P. mitchelli (Gertsch 1971)V-MF13
         |    |--P. monjarazi Valdez-Mondragón & Francke 2013V-MF13
         |    |--P. osorioi (Bolivar & Pieltain 1946)V-MF13
         |    |--P. oztotl Valdez-Mondragón & Francke 2011V-MF13
         |    |--P. paradoxusH95
         |    |--P. pearsei (Chamberlin & Ivie 1938)GE02
         |    |--P. pelaezi (Coronado-Gutierrez 1970)V-MF13
         |    |--P. platnicki Valdez-Mondragón & Francke 2011V-MF13
         |    |--P. reddelli (Gertsch 1971)V-MF13
         |    |--P. sbordonii (Brignoli 1974)V-MF13
         |    `--P. spinotibialis (Goodnight & Goodnight 1952)V-MF13
         `--Cryptocellus Westwood 1874B-TP08
              |--*C. foedus Westwood 1874G-TP08
              |--C. abaporu Bonaldo & Pinto-da-Rocha 2003BP-R03
              |--C. bonetiGE02
              |--C. centralis Fage 1921B-TP08
              |--C. glenoides Cooke & Shadab 1973B-TP08
              |--C. goodnightiLA23
              |--C. isthmusA99
              |--C. lampeliH95
              |--C. magnus Ewing 1929 [incl. C. manni Ewing 1929]B-TP08
              |--C. narino Platnick & Paz 1979B-TP08
              |--C. peckorum Platnick & Shadab 1977B-TP08
              |--C. platnicki Botero-Trujillo & Pérez 2008B-TP08
              `--C. simonisBP-R03

*Type species of generic name indicated

References

[A99] Ax, P. 1999. Das System der Metazoa II. Ein Lehrbuch der phylogenetischen Systematik. Gustav Fisher Verlag: Stuttgart (translated: 2000. Multicellular Animals: The phylogenetic system of the Metazoa vol. 2. Springer).

[BP-R03] Bonaldo, A. B., & R. Pinto-da-Rocha. 2003. On a new species of Cryptocellus from the Brazilian Amazon (Arachnida, Ricinulei). Revista Ibérica de Aracnología 7: 103–108.

[B-TP08] Botero-Trujillo, R., & G. A. Pérez. 2008. A new species of Cryptocellus (Arachnida, Ricinulei) from northwestern Colombia. Journal of Arachnology 36 (2): 468–471.

[F04] Fritsch, A. 1904. Palaeozoische Arachniden. Selestverlag: Prague.

[GE02] Giribet, G., G. D. Edgecombe, W. C. Wheeler & C. Babbitt. 2002. Phylogeny and systematic position of Opiliones: a combined analysis of chelicerate relationships using morphological and molecular data. Cladistics 18: 5–70.

[HS04] Hansen, H. J., & W. Sørensen. 1904. On Two Orders of Arachnida: Opiliones, especially the suborder Cyphophthalmi, and Ricinulei, namely the family Cryptostemmatoidae. Cambridge University Press: Cambridge.

[H02] Harvey, M. S. 2002. The neglected cousins: what do we know about the smaller arachnid orders? Journal of Arachnology 30 (2): 357–372.

[H95] Humphreys, W. F. 1995. Chorion surface features of chelicerate eggs. Records of the Western Australian Museum Supplement 52: 171–181.

[LA23] Lustri, L., J. B. Antcliffe, F. Saleh, C. Haug, L. Laibl, R. J. Garwood, J. T. Haug & A. C. Daley. 2023. New perspectives on the evolutionary history of xiphosuran development through comparison with other fossil euchelicerates. Frontiers in Ecology and Evolution 11: 1270429.

[S93] Selden, P. A. 1993. Arthropoda (Aglaspidida, Pycnogonida and Chelicerata). In: Benton, M. J. (ed.) The Fossil Record 2 pp. 297–320. Chapman & Hall: London.

[SF15] Sharma, P. P., R. Fernández, L. A. Esposito, E. González-Santillán & L. Monod. 2015. Phylogenomic resolution of scorpions reveals multilevel discordance with morphological phylogenetic signal. Proceedings of the Royal Society of London Series B—Biological Sciences 282: 20142953.

[V-MF13] Valdez-Mondragón, A., & O. F. Francke. 2013. Two new species of ricinuleids of the genus Pseudocellus (Arachnida: Ricinulei: Ricinoididae) from southern Mexico. Zootaxa 3635 (5): 545–556.