Peripatopsidae or the Southern Velvet Worms are one of two extant

families Family (from ) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictability, structure, and safety as ...

of velvet worm. This family includes more than 140 described

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

distributed among 41

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

, but some authorities deem only 131 of these species to be valid. The French

zoologist Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinct, and how they interact with their ecosystems. Zoology is one ...

Eugène Louis Bouvier Eugène Louis Bouvier (9 April 1856 in Saint-Laurent-en-Grandvaux – 14 January 1944 in Paris) was a French entomologist and carcinologist. Bouvier was a professor at the Muséum national d'histoire naturelle. Biography Following graduation at t ...

proposed this family in 1905 with '' Peripatopsis'' as the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

Description

The Peripatopsidae exhibit relatively many characteristics that are perceived as original or "primitive" with respect to the Peripatidae. The species in this family have relatively few legs, ranging from 13 pairs (in '' Ooperipatellus nanus'') to a maximum of 29 pairs (in '' Paraperipatus papuensis''). Behind or between the last leg pair is the genital opening (

gonopore A gonopore, sometimes called a gonadopore, is a genital pore in many invertebrates. Hexapods, including insects, have a single common gonopore, except mayflies, which have a pair of gonopores. More specifically, in the unmodified female, it is ...

). This family includes both

oviparous Oviparous animals are animals that reproduce by depositing fertilized zygotes outside the body (i.e., by laying or spawning) in metabolically independent incubation organs known as eggs, which nurture the embryo into moving offsprings kno ...

genera (e.g., '' Ooperipatellus'' and '' Ooperipatus'') and

viviparous In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juve ...

genera, which adopt various modes of supplying nourishment to their embryos, ranging from lecithotrophic

ovoviviparity Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop inside eggs that r ...

(with yolky eggs retained in their uteri, e.g., '' Peripatoides'') to matrotrophic

viviparity In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juv ...

(with little or no yolk in the eggs retained in their uteri and nourishment supplied by the mother instead, e.g., '' Metaperipatus'', '' Opisthopatus'', '' Paraperipatus'', '' Paropisthopatus'', and '' Peripatopsis''). The Peripatopsidae lack a placenta, however, which has been found in velvet worms only in the

neotropical The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In biogeogra ...

Peripatidae. Most genera in this family have only 15 pairs of legs; one genus has 15 or fewer ('' Regimitra'', with 14 or 15 in the only species), and another genus includes only species with fewer than 15 ('' Ooperipatellus'', with 13 or 14, depending on the species). Two genera are characterized by 16 pairs of legs ('' Occiperipatoides'' and '' Paropisthopatus''), another genus has 15 or 16 ('' Peripatoides''), and only four genera include velvet worms with more than 16: '' Opisthopatus'' (with 16 to 18), '' Peripatopsis'' (with 16 to 25), '' Metaperipatus'' (with 19 to 22), and '' Paraperipatus'' (with 21 to 29). Although leg number is fixed within most peripatopsid species, the four genera that feature more than 16 leg pairs exhibit some variation in leg number within species as well as among species. Peripatopsid species with more legs also feature greater intraspecific variation in leg number.

Distribution

The distribution of the Peripatopsidae (also known as southern velvet worms) is circumaustral; in particular, they inhabit

Australasia Australasia is a subregion of Oceania, comprising Australia, New Zealand (overlapping with Polynesia), and sometimes including New Guinea and surrounding islands (overlapping with Melanesia). The term is used in a number of different context ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

and

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

. Most genera in this family are found in

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, one genus ('' Peripatoides'') is found in

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

, and another ('' Ooperipatellus'') is found in both; two genera ('' Opisthopatus'' and '' Peripatopsis'') are found in South Africa, two others ('' Metaperipatus'' and '' Paropisthopatus'') are found in Chile, and one other ('' Paraperipatus'') is found in

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...

and

New Guinea New Guinea (; Hiri Motu: ''Niu Gini''; , fossilized , also known as Papua or historically ) is the List of islands by area, world's second-largest island, with an area of . Located in Melanesia in the southwestern Pacific Ocean, the island is ...

Taxonomy

Phylogeny

Peripatopsidae is divided into two main clades: one with members in

Southern Africa Southern Africa is the southernmost region of Africa. No definition is agreed upon, but some groupings include the United Nations geoscheme for Africa, United Nations geoscheme, the intergovernmental Southern African Development Community, and ...

and

, and another with members in

. The majority of species belong to the Australasian clade, with most occurring in

. Below is a genus-level phylogeny of Peripatopsid velvet worms. As it doesn't include all genera, it eventually needs updating.

Genera

The family contains the following genera: * '' Acanthokara'' Reid, 1996 * '' Aethrikos'' Reid, 1996 * '' Aktinothele'' Reid, 1996 * '' Anoplokaros'' Reid, 1996 * '' Austroperipatus'' Baehr, 1977 * '' Baeothele'' Reid, 1996 * '' Centrorumis'' Reid, 1996 * '' Cephalofovea'' Ruhberg et al., 1988 * ''

Critolaus Critolaus (; ''Kritolaos''; c. 200 – c. 118 BC) of Phaselis was a Greek philosopher of the Peripatetic school. He was one of three philosophers sent to Rome in 155 BC (the other two being Carneades and Diogenes of Babylon), where their doctrin ...

'' Reid, 1996 * '' Dactylothele'' Reid, 1996 * '' Diemenipatus'' Oliveira, Ruhberg, Rowell & Mayer, 2018 * '' Dystactotylos'' Reid, 1996 * '' Euperipatoides'' Ruhberg, 1985 * '' Florelliceps'' Tait & Norman, 2001 * '' Hylonomoipos'' Reid, 1996 * '' Konothele'' Reid, 1996 * '' Kumbadjena'' Reid, 2002 * '' Lathropatus'' Reid, 2000 * '' Leucopatus'' (Ruhberg, Mesibov, Briscoe & Tait, 1991) * '' Leuropezos'' Reid, 1996 * '' Mantonipatus'' Ruhberg, 1985 * '' Metaperipatus'' Clark, 1913 * '' Minyplanetes'' Reid, 1996 * '' Nodocapitus'' Reid, 1996 * '' Occiperipatoides'' Ruhberg, 1985 * '' Ooperipatellus'' Ruhberg, 1985 * '' Ooperipatus'' Dendy, 1900 * '' Opisthopatus'' Purcell, 1899 * '' Paraperipatus'' Ruhberg, 1985 * '' Paropisthopatus'' Ruhberg, 1985 * '' Peripatoides'' Pocock, 1894 * '' Peripatopsis'' Pocock, 1894 * '' Phallocephale'' Reid, 1996 * '' Planipapillus'' Reid, 1996 * '' Regimitra'' Reid, 1996 * '' Ruhbergia'' Reid, 1996 * '' Sphenoparme'' Reid, 1996 * '' Tasmanipatus'' Ruhberg et al. 1991 * '' Tetrameraden'' Reid, 1996 * '' Vescerro'' Reid, 1996 * '' Wambalana'' Reid, 1996

References

* * {{Authority control Onychophoran families Taxa named by Eugène Louis Bouvier