, 128:305 | Cite as

A fossil trigonotarbid arachnid with a ricinuleid-like pedipalpal claw

  • Jason A. DunlopEmail author
  • Carsten Kamenz
  • Giovanni Talarico
Original Paper


A fossil trigonotarbid (Arachnida: Trigonotarbida) assigned to Palaeocharinus sp. from the Early Devonian (c. 410 Ma) Rhynie cherts of Aberdeenshire, Scotland, UK is described, specifically for a previously unrecognised feature of the distal end of the pedipalp. This exhibits a small chela formed from a movable, unpaired apotele articulating against a slightly shorter, fixed projection from the inferior surface of the tarsus. Among other arachnids, this morphology has only previously been observed in the rare and enigmatic Carboniferous—Recent taxon Ricinulei. This character offers explicit support for a monophylum (Trigonotarbida + Ricinulei); a hypothesis previously based on opisthosomal characters which (if correct) would draw Ricinulei within the so-called Pantetrapulmonata clade (i.e. spiders and their closest relatives). Our data is not consistent with Ricinulei’s traditional position as sister-group of mites (Acari) and is an example of how considering extinct taxa may help to resolve the position of a ‘difficult’ living group.


Trigonotarbida Ricinulei Pedipalp Chela Fossil 



We thank Hans Kerp and Hagen Hass (Münster) for making this fossil material available to us and Andrew Ross (London) for access to further fossils in his care. GT thanks José G. Palacios-Vargas (México-City) for providing ricinuleids. Gerhard Scholtz (Berlin) and Gerd Alberti (Greifswald) are thanked for advice and encouragement and Greg Edgecombe (London) for valuable comments on an earlier manuscript draft.


  1. Alberti G (2000) Chelicerata. In: Jamieson BGM (ed) Progress in male gamete ultrastructure and phylogeny (Vol. IX; Part B). Oxford and IBH Publishing Co. Pvt. Ltd., New Dehli, Calcutta, pp 311–388Google Scholar
  2. Alberti G, Palacios-Vargas JG (1984) Fine structure of spermatogenesis and mature spermatozoa in Cryptocellus boneti Bolivar y Pieltain, 1941 (Arachnida, Ricinulei). J Ultrastruct Res 87:1–12. doi: 10.1016/S0022-5320(84)90111-4 CrossRefGoogle Scholar
  3. Chamberlin RV, Ivie W (1938) Arachnida of the orders Pedipalpida, Scorpionida and Ricinuleida. Carnegie Inst Wash Pub 491:101–107Google Scholar
  4. Claridge MF, Lyon AG (1961) Lung-books in the Devonian Palaeocharinidae (Arachnida). Nature 191:1190–1191. doi: 10.1038/1911190b0 CrossRefGoogle Scholar
  5. Cooke JAL (1967) Observations on the biology of Ricinulei (Arachnida) with descriptions of two new species of Cryptocellus. J Zool 151:31–42CrossRefGoogle Scholar
  6. Dunlop JA (1994) Palaeobiology of the trigonotarbid arachnids. Unpublished PhD Thesis, University of Manchester, UKGoogle Scholar
  7. Dunlop JA (1996) Evidence for a sister group relationship between Ricinulei and Trigonotarbida. Bull Br Arachnol Soc 9:267–273Google Scholar
  8. Dunlop JA, Alberti G (2008) The affinities of mites and ticks: a review. J Zoological Syst Evol Res 46:1–18Google Scholar
  9. Fayers S, Trewin NH (2004) A review of the palaeoenvironments and biota of the Windyfield chert. Trans R Soc Edinb Earth Sci 94:325–339Google Scholar
  10. Fayers S, Dunlop JA, Trewin NH (2005) A new early Devonian trigonotarbid arachnid from the Windyfield chert, Rhynie, Scotland. J Syst Palaeontology 2:269–284. doi: 10.1017/S147720190400149X CrossRefGoogle Scholar
  11. Giribet G, Edgecombe GD, Wheeler WC, Babbitt C (2002) Phylogeny and systematic position of Opiliones: a combined analysis of chelicerate relationships using morphological and molecular data. Cladistics 18:5–70PubMedGoogle Scholar
  12. Hansen HJ, Sørensen W (1904) On two orders of Arachnida. Cambridge University Press, CambridgeGoogle Scholar
  13. Harvey MS (2003) Catalogue of the smaller arachnid orders of the world: Amblypygi, Uropygi, Schizomida, Palpigradi, Ricinulei and Solifugae. CSIRO Publishing, CollingwoodGoogle Scholar
  14. Hirst S (1923) On some arachnid remains from the Old Red Sandstone (Rhynie Chert bed, Aberdeenshire). Ann Mag Nat Hist 12(9):455–474Google Scholar
  15. Hirst S, Maulik S (1926) On some arthropod remains from the Rhynie Chert (Old Red Sandstone). Geol Mag 63:69–71CrossRefGoogle Scholar
  16. Kamenz C, Dunlop JA, Scholtz G, Kerp H, Hass H (2008) Microanatomy of Early Devonian book lungs. Biol Lett 1–4. doi: 10.1098/rsbl.2007.0597
  17. Karsch F (1892) Ueber Cryptostemma Guér. als einzigen recenter Ausläufer der fossilen Arachnoideen-Ordnung Meridogastra Thor. Berl Entomol Z 37:25–32. doi: 10.1002/mmnd.18920370108 CrossRefGoogle Scholar
  18. Legg G (1976) The external morphology of a new species of ricinuleid (Arachnida) from Sierra Leone. Zool J Linn Soc 59:1–58. doi: 10.1111/j.1096-3642.1976.tb01007.x CrossRefGoogle Scholar
  19. Lindquist EE (1984) Current theories on the evolution of major groups of Acari and on their relationships with other groups of Arachnida with consequent implications for their classification. In: Griffiths DA, Bowman CE (eds) Acarology, vol 1. Ellis Horwood Ltd., Chichester, pp 28–62Google Scholar
  20. Petrunkevitch AI (1949) A study of Palaeozoic Arachnida. Trans Conn Acad Arts Sci 37:69–315Google Scholar
  21. Pinto-da-Rocha R, Bonaldo AB (2007) A new species of Cryptocellus (Arachnida, Ricinulei) from Oriental Amazonia. Zootaxa 1386:47–51Google Scholar
  22. Pittard K, Mitchell RW (1972) Comparative morphology of the life stages of Cryptocellus pelaezi (Arachnida, Ricinulei). Grad Stud Tex Tech Uni 1:3–77Google Scholar
  23. Pollock J (1967) Notes on the biology of Ricinulei (Arachnida). J W Afr Sci Assoc 12:19–22Google Scholar
  24. Rice CM, Trewin NH, Anderson LI (2002) Geological setting of the Early Devonian Rhynie cherts, Aberdeenshire, Scotland: an early terrestrial hot springs system. J Geol Soc London 159:203–214. doi: 10.1144/0016-764900-181 CrossRefGoogle Scholar
  25. Selden PA (1992) Revision of the fossil ricinuleids. Trans R Soc Edinb Earth Sci 83:595–634Google Scholar
  26. Selden PA, Shear WA, Bonamo PM (1991) A spider and other arachnids from the Devonian of New York, and reinterpretations of Devonian Araneae. Palaeontology 34:241–281Google Scholar
  27. Shear WA, Selden PA, Rolfe WDI, Bonamo PM, Grierson JD (1987) New terrestrial arachnids from the Devonian of Gilboa, New York (Arachnida, Trigonotarbida). Am Mus Novit 2901:1–74Google Scholar
  28. Shultz JW (1990) Evolutionary morphology and phylogeny of Arachnida. Cladistics 6:1–38. doi: 10.1111/j.1096-0031.1990.tb00523.x CrossRefGoogle Scholar
  29. Shultz JW (2007) A phylogenetic analysis of the arachnid orders based on morphological characters. Zool J Linn Soc 150:221–265. doi: 10.1111/j.1096-3642.2007.00284.x CrossRefGoogle Scholar
  30. Thorell T, Lindström G (1885) On a Silurian Scorpion from Gotland. Kungl Svenska Vetenskapsakad hand 21:1–33Google Scholar
  31. Tourinho AL, Salette de Azevedo C (2007) A new Amazonian Cryptocellus Westwood (Arachnida, Ricinulei). Zootaxa 1540:55–60Google Scholar
  32. Tuxen SL (1974) The African genus Ricinoides (Arachnida, Ricinulei). J Arachnol 1:85–106Google Scholar
  33. van der Hammen L (1979) Comparative studies in Chelicerata I. The Cryptognomae (Ricinulei), Architarbi and Anactinotrichida). Zool Verh Leiden 174:1–62Google Scholar
  34. van der Hammen L (1989) An introduction to comparative arachnology. SPB Academic Publishing bv, The HagueGoogle Scholar
  35. Weygoldt P, Paulus HF (1979) Untersuchungen zur Morphologie, Taxonomie und Phylogenie der Chelicerata. Z zool Syst Evolut-forsch 17(85–116):177–200Google Scholar
  36. Wheeler WC, Hayashi CY (1998) The phylogeny of the extant chelicerate orders. Cladistics 14:173–192. doi: 10.1111/j.1096-0031.1998.tb00331.x CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Jason A. Dunlop
    • 1
    Email author
  • Carsten Kamenz
    • 2
  • Giovanni Talarico
    • 3
  1. 1.Museum für Naturkunde, Leibniz Institute for Research on Evolution and Biodiversity Humboldt University BerlinBerlinGermany
  2. 2.Institut für Biologie/Vergleichende ZoologieHumboldt Universität zu BerlinBerlinGermany
  3. 3.Zoologisches Institut und MuseumErnst-Moritz-Arndt-UniversitätGreifswaldGermany

Personalised recommendations