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Peripatopsis

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Peripatopsis
Illustration of the oncopods (legs) of Peripatopsis capensis
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Onychophora
Family: Peripatopsidae
Genus: Peripatopsis
Pocock, 1894
Species

See text

Peripatopsis is a genus of velvet worms in the Peripatopsidae family.[1][2] These velvet worms are found in the KwaZulu-Natal, Western Cape, and Eastern Cape provinces of South Africa.[3] This genus was proposed by the British zoologist Reginald I. Pocock in 1894 with Peripatopsis capensis designated as the type species.[4]

Description

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The number of legs in this genus ranges from as few as 16 pairs (e.g., in P. clavigera)[5] to as many as 25 pairs (in P. moseleyi) and varies within species when the number is greater than 18 pairs.[3] Velvet worms in this genus feature a last pair of legs (the genital pair) that is rudimentary or reduced in size, mainly in males. The feet in this genus feature three distal papillae: two anterior and one posterior. The gonopore in the male is cross-shaped but in the female takes the form of a longitudinal slit.[3]

Reproduction

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This genus exhibits matrotrophic viviparity, that is, mothers in this genus retain eggs in their uteri and supply nourishment to their embryos, but without any placenta.[6] Eggs are fertilized through dermal insemination.[3] Males place spermatophores on the skin of females, which allows the entry of sperm at the point of contact. Embryonic development in this genus takes 12 to 13 months, during which the mother contains up to 20 embryos, all at about the same stage of development. The young are born alive tail first, one or two at a time, all within a short period of time. The young resemble adults in form but are smaller.[7]

Species

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The genus Peripatopsis consists of the following species:

References

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  1. ^ Oliveira I. S.; Hering L.; Mayer, G. "Updated Onychophora checklist". Onychophora Website. Retrieved 13 July 2016.
  2. ^ Oliveira, I. S.; Read, V. M. S. J.; Mayer, G. (2012). "A world checklist of Onychophora (velvet worms), with notes on nomenclature and status of names". ZooKeys (211): 1–70. Bibcode:2012ZooK..211....1O. doi:10.3897/zookeys.211.3463. PMC 3426840. PMID 22930648.
  3. ^ a b c d Ruhberg, Hilke; Daniels, Savel R. (2013-05-24). "Morphological assessment supports the recognition of four novel species in the widely distributed velvet worm Peripatopsis moseleyi sensu lato (Onychophora : Peripatopsidae)". Invertebrate Systematics. 27 (2): 131–145. doi:10.1071/IS12069. ISSN 1447-2600. S2CID 86036034.
  4. ^ Pocock, R. I. (1894). "Contributions to our Knowledge of the Arthropod Fauna of the West Indies.-Part III. Diplopoda and Malacopoda, with a Supplement on the Arachnida of the Class Pedipalpi". Journal of the Linnean Society of London, Zoology. 24 (157): 473–544 [519]. doi:10.1111/j.1096-3642.1894.tb02494.x. ISSN 0368-2935.
  5. ^ Barnes, Aaron; Reiss, Till; Daniels, Savel R. (2020). "Systematics of the Peripatopsis clavigera species complex (Onychophora : Peripatopsidae) reveals cryptic cladogenic patterning, with the description of five new species". Invertebrate Systematics. 34 (6): 569–590. doi:10.1071/IS19071. ISSN 1445-5226. S2CID 221666417.
  6. ^ Mayer, Georg; Franke, Franziska Anni; Treffkorn, Sandra; Gross, Vladimir; de Sena Oliveira, Ivo (2015), Wanninger, Andreas (ed.), "Onychophora", Evolutionary Developmental Biology of Invertebrates 3, Vienna: Springer Vienna, pp. 53–98, doi:10.1007/978-3-7091-1865-8_4, ISBN 978-3-7091-1864-1, retrieved 2023-02-15
  7. ^ Hamer, M.L.; Samways, M.J.; Ruhberg, H. (1997). "A review of the Onychophora of South Africa, with discussion of their conservation". Annals of the Natal Museum. 38 (1): 283–312.