Peripatopsidae

As Peripatopsidae designates one one Family of Stummelfuessern (Onychophora). The animals, their appearance to worms with legs reminds, exclusively live in the moderate zone of the Southern Hemisphere. Contrary to the other Stummelfuessergruppe, that Peripatidae, there is a set of kinds, no living boy to the world brings, separate eggs put, thus ovipar are.

The family was described for the first time in the year 1907 and after the type kind Peripatopsis designated.

Structure

Peripatopsidae kinds exist in numerous colors, however a schillerndes cyan is most frequent. With a length between 0,5 and 8 centimeters they are usually shorter than the Peripatidae kinds and have even fewer legs; the number of these stummelfoermigen appendices of body is always constant and varied within a kind between 13 and 29 pairs. The last pair of legs sometimes diminished, occasionally apparent also not even available.

General anatomy corresponds to a large extent that everything Stummelfuesser and is in detail discussed in the appropriate article; in the following therefore special characteristics of the Peripatopsidae are primarily. In addition belong for example the nerve supply of the heart, those differently than with the Peripatidae exclusive by a back nerve strand takes place, in addition, the simple structure of the salivary glands, no reservoir possess, in that the saliva buffered will could.

Cruraldruesen, special organs, within the stub legs lie, often into the body cavity in-rich and probably primarily of communication between the sexes serve, occur in principle with both sexes. As also with the Peripatidae, with those they however only with the males are, separate they by openings at the belly-lateral leg beginning, those Cruralpapillen, chemical messenger materials, so mentioned Pheromones, off. Coxalsaecke, Structures, with other Stummelfuessern probably the water absorption serve, are not within the Peripatopsidae.

The genital aperture, with the Peripatidae always between that next to last Pair of legs lies, is with the Peripatopsidae behind or between that the latter received pair of legs, which supports the thesis already addressed, that a further pair of legs was lost in the process of the master history of the Peripatopsidae.

Also at the reproduction organs some characteristics show up: Thus the eggs lie in the ovaries of the females exogenously, that means, that those Follicle in the contact with the body cavity, that Haemocoelom stand and from this nutrients to take up can, about in order to develop Dotter. One Plazenta, like it with many Peripatidae kinds is, does not occur against it in principle.

With the males likewise some special adjustments exist. Thus kinds of the kind possess for example Paraperipatus a proper Penis; its employment with a kopulation could not be observed however so far. Some mobile structures are still more unusual, at the head of the males of numerous Australian kinds to find leave themselves. It probably concerns modifications of the Sinnespapillen occurring with all Stummelfuessern on the skin, those here to thorns, Claws or Stiletten are trained and probably the transmission of sperm cells packages serve. With the kind Florelliceps stutchburyae existed for example an individual long thorn, from a skin fold to be put forward can, runs for instance from eye level forward.

Spreading and habitat

The Peripatopsidae lives in the moderate zones of the Southern Hemisphere and points thereby a in such a way specified zirkumaustrale Spreading up: They are in the east and southwest, locally also in the central south Australia, in Tasmanien, New Guinea and in New Zealand, besides also in Chile and in two coastal strips confine South Africa, on the one hand south that Cape fold mountains, on the other hand beyond the eastern Great escarpment on the precipitation-rich sea side.

The geographical distribution of the kinds testifies the origin of the group on the former southern supercontinent Gondwana; they were transported from there with their current habitat in the course continental drift into its present circulation areas.

Like all Stummelfuesser also the Peripatopsidae is dependent on a high air humidity. They live therefore only in damp surrounding field, particularly in forests, for instance under stones, in or under totholz as umgestuerzten trunks or in the leaves layer of the soil. Into southwest and south Australia they come also in the drying forest, in South Africa even on otherwise unbewachsenem grass country forwards. A South African kind, Peripatopsis alba, lives in caves.

Likewise in South Africa so far the largest well-known population density was determined within the family; there are isolated up to 10 individuals per square meter soil.

From Australia, its Stummelfuesser-fauna was so far best examined, is well-known, frequently genetically from each other definable kinds the same habitat divide, which on one sympatrische kind formation, thus the development of two or several kinds without geographical isolation to refer to could.

Reproduction

All Peripatopsidae kinds reproduce themselves sexually. The genetic variety within a population is often not very large however at least with the particularly well examined Australian kinds, which otherwise closely used on frequent mating among brothers and sisters or animals, in individual cases also on strong stabilizing Selection to close leaves.

Nearly everywhere the fertilization of the females takes place vaginal. With living-bearing kinds from it the problem results, that the growing up embryos in the Uterus pregnant women of the female the way of the sperm cellses to the ovaries obstruct. For this reason fertilization finds supposed with most kinds before the sex-ripe instead of. Within the female the sperm cellses can remain lebensfaehig in special pouches for more than nine months and fertilize the eggs in this way at a later time. In all cases the pouches do not serve however the long-term storage of the seed - sometimes only few days lie, between insemination and fertilization so that more comes to them the function of a short time memory.

The mode of the sperm cells transmission is different with the different kinds: As previously mentioned comes within the kind Paraperipatus a penisartige structure forwards, however yet in function to be observed could not, while with many Australian kinds with the males special structures at the head exist, those the sperm cells transfer to likewise serve seem. More exact observations only lie from the kind Florelliceps stutchburyae from new South Wales forwards: Here a special thorn apparent serves the positioning of a sperm cells package (Spermatophore) in the Vagina of the female; possibly it is there also already opened by this and the contained sperm cellses is set free in such a way. During kopulation the male presses its head firmly against the genital opening (Gonopore) the female, that their partner thereby supports, by with the claws of the last pair of legs the Hautpapillen of the male present on the top seizing and clasping. Both animals are so firmly connected in this mating position, that even the handling did not lead by the examining scientists to a task of the mating position. However the animals slow lead, but coordinated movements out, with those obviously the female in front present leads. Like the Spermatophore from that genital aperture of the male at its head arrives, is still unsettled. Possibly this unusual mating variant developed as adjustment to close habitats, like it for instance within died trunks prevail - there it concerns a very effective transmission path for the sperm cellses.

Two South African kinds have completely different way, Peripatopsis capensis and Peripatopsis sedgwicki hit. At both fertilization does not take place by the Vagina; accordingly also no pouches exist for the storage of the sperm cellses. Instead the male in the diameter about a sperm cells package at the flanks or on the back of the female, large, puts down a millimeter. Special one Amoebozyten cells mentioned, in the blood of the female are contained, separate thereupon enzymes off, aimed the skin underneath the sperm cells package and at the same time its covering dissolve. As consequence sperm cellses by these arrive produced "wound" into the body concavity of the female and penetrate from this from to the ovaries, their wall it penetrieren. In this way they arrive at the Eizellen, to be now fertilized can. This after the scientific name for the outside, dead Hautschicht cuticular fertilization mentioned is to that extent unusual, when that normal skin injuries lead with Stummelfuessern by bacterial infections usually very fast to death - it must exist thus a mechanism, in the case of the "mating wound" such infections effectively prevents.

Although the mating often already begins with the females before the sex-ripe, quite further kopulationen are possible in the further process of the life. Female of the Australian kind Euperipatoides rowelli in the process of their life by several partners are apparent fertilized, so that it can happen, that new generation of different fathers grows up at the same time in the female.

Most Peripatopsidae is - like all animals of their group of sisters, the Peripatidae - living-bearing; there are however some egg-laying (ovipare) kinds. Into with 1,3 to 2.0 millimeters the large, from a chitinhaltigen bowl surrounding eggs is then an accordingly large quantity of Dotter, nourish themselves the growing up embryos of. The remaining kinds divide into egg-living-bearing (ovovivipare) and genuinly living-bearing (vivipare) forms up, whereby a vivipare way of life is only with few kinds. Differently than with many Peripatidae kinds also in principle no Plazenta exists with them.

It is considered as probable, that the original reproduction mode of the Peripatopsidae ovovivipar was; both Oviparie and Viviparie probably secondarily developed thus.

The development time of the embryos is at between six and seventeen months. With the living-bearing kinds come in each case to two young animals to the world, those are usually somewhat more brightly as their parents colored, but already have the leg number correct for their respective kind.

At males the first mating takes place after approximately nine to eleven months; it is well-known, that they a higher mortality exhibit than the females. These pairs of itself depending upon kind for the first time at the age of 9 to 24 months. The first birth and/or oviposition takes place accordingly after approximately two to three years; the average descendant number varies again kind-dependently between 6 and 23 young animals per year.

Endangerment

There many Peripatopsidae only into that 1990er Years were discovered and besides many regions as for instance New Guinea to be still hardly scientifically examined could, is present only few reliable information about the actual endangerment of most kinds.

A kind, Peripatiopsis leonina, possibly already became extinct, becomes however together with Opisthopatus roseus at present of that Internationally union for Conservation OF Nature and Natural Resources still as critical of becoming extinct threatens estimated. Both kinds originate from South Africa. In addition come Tasmanipatus leonina from Tasmanien, as threatened applies, and four further kinds, as endangered to be classified: These are in detail Peripatopsis clavigera and Peripatopsis alba from South Africa as well as Peripatoides indigo and Peripatoides suteri from New Zealand.

The protection status is different depending upon state. While in South Africa all Stummelfuesser is legally protected and both is necessary for the a collecting and for the export of the animals special permission, no special regulations are well-known from Chile. In Australia exist none collect -, probably however export restrictions. As unusually may particularly in two tasmanische kinds, Tasmanipatus anophtalmus and Tasmanipatus baretti aligned regional project apply, the in such a way specified velvet worm conservation flat, to these two groups an attention which can be found only rarely with eddyless animals dedicates.

Master and discovery history

The Peripatopsidae is fossil does not deliver, so that their master history from the knowledge of the modern kinds and its geographical spreading must be opened.

They separated probably already before breaking the southern supercontinent open Gondwana approximately 130 million years ago of their presumed group of sisters, the Peripatidae. The fragmentation of the Stummelfuesser took place thus probably already in the earth-history epochs from Trias or Law. But also 100 million years old speaks chalk-temporal Stummelfuesser fossil, Cretoperipatus burmiticus, already to the family the Peripatidae belongs.

The further master history of the family can be opened among other things by an Retrovikarianz analysis in such a way specified: This is based on the principle, that geographically neighbouring kinds are related more closely with one another than such, in far from each other distant circulation areas are domestic. It becomes nontrivial thereby, that during geological periods those Movement of the continents to each other to be considered must. An Retrovikarianz analysis can supply in each case a rough estimate and may not not with on morphologic or molecular-genetic characteristics are based phylogenetischen Analysis to be confounded. In the concrete case the following picture results:

Peripatopsidae | -- South African kinds |-n. N.
   | -- Chilean kinds | -- kinds of New Zealand | -- Australian kinds (inclusive Papua New Guinea)

The separation between the South African kinds and all different is thus probably the urspruenglichste - it probably found in late law or the early Chalk time instead of, as still another land connection between Africa, South America and Australia via Antarktika existed. Also the splitting off of a first group egg-laying (more oviparer) kinds probably decreases/goes back to this time.

The Chilean Stummelfuesser-fauna is relatively closely related to fauna of New Zealand and the Australian. The latter forms however probably even none monophyletische Group - some Australian kinds apparent find their closest relatives in New Zealand. Settling Australia took place probably from Tasmanien and southeast Australia, whereby the latter was in the meantime flooded and secondarily rekolonisiert then.

In the eozaen probably about 37 million years ago, at one time, to Australia was isolated from all other continents already, the second line of development of oviparer kinds there then probably developed. The settlement of new Guinea can only after that Pliozaen taken place its, since the area was before under water. It is obvious, to assume, that the animals over during that Ice ages of the Pleistozaens existing land bridge from Australia immigrated - molecular-biological realizations contradict however at present this assumption.

Systematics

Whether it itself with the Peripatopsidae around a natural (monophyletische) group acts, the all descendants of its common moving forward covers, is not undisputed, is considered however as good working hypothesis, even if isolated arguments for a classification of the Peripatidae into the Peripatopsidae speak.

By extensive taxonomische Work in Australia is from there most that altogether 37 Kinds admits, the 92 Kinds cover. Many of it cannot be differentiated however outwardly. This therefore also as kryptisch designated kinds become instead by molecular-biological aids how Allozym-Electrophoresis from each other defined.

The following overview lists the well-known kinds with their circulation area in alphabetical order:

• Acanthokara (new South Wales, Australia)
• Aethrikos (new South Wales, Australia)
• Akthinothele (Queensland, Australia)
• Anoplokaros (new South Wales, Australia)
• Austroperipatus (Queensland, Australia)
• Baeothele (new South Wales, Australia)
• Centrorumis (new South Wales, Australia)
• Cephalofovea (new South Wales, Australia)
• Critolaus (Queensland, Australia)
• Dactylothele (Queensland, Australia)
• Dystactotylos (Queensland, Australia)
• Euperipatoides (new South Wales, Australia)
• Florelliceps (new South Wales, Australia)
• Hylonomoipos (Queensland, Australia)
• Konothele (Queensland, Australia)
• Lathropatus (southeast Australia)
• Leuropezos (Queensland, Australia)
• Mantonipatus (south Australia)
• Metaperipatus (South America)
• Minyplanetes (Queensland, Australia)
• Nodocapitus (Queensland and new South Wales, Australia)
• Occiperipatoides (southwest Australia)
• Ooperipatellus (south Australia)
• Ooperipatus (Victoria and southeast Australia)
• Opisthopatus (South Africa)
• Paraperipatus (new Guinea)
• Paropisthopatus ?
• Peripatoides (New Zealand)
• Peripatopsis (South Africa)
• Phallocephale (new South Wales, Australia)
• Planipallipus (new South Wales and Victoria, Australia)
• Regimitra (new South Wales, Australia)
• Ruhbergia (new South Wales, Australia)
• Sphenoparme (Queensland, Australia)
• Symperipatus ?
• Tasmania (Tasmanien, Australia)
• Tasmanipatus (Tasmanien, Australia)
• Tetrameraden (new South Wales, Australia)
• Vescerro (Queensland, Australia)
• Wambalana (new South Wales, Australia)

The supposed masterhistorical verwandtschaftsverhaeltnisse of the kinds derived from molecular-genetic data are shown in the following diagram to each other. The kinds Florelliceps and Tasmania are not yet contained in it for lack of phylogenetischer information; the kind Ooperipatus is considered as para or even polyphyletisch and is specified as non-natural group therefore only for the sake of the form here.

Peripatopsidae | - -Tasmanipatus |-n. N.
   | - -Peripatoides  |-n. N.
      |-n. N.
      | | - -Ooperipatellus parvus     | |-n. N.
      | | - -Ooperipatellus (other kinds) | |-n. N.
      | | - -Opistopathus     | |-n. N.
      | | - -Peripatopsis     | |-n. N.
      | | - -Metaperipatus     | | - -Paraperipatus     | |-n. N.
         | - -Euperipatoides        |-n. N.
            | - -Occiperipatoides           |-n. N.
               | - -Centrorumis              |-n. N.
                  | - -Minyplanetes                 |-n. N.
                     | - -Nodocapitus                    |-n. N.
                        | - -Acanthokara                       | - -Aktinothele                       | - -Austroperipatus                       | - -Baeothele                       | - -Cephalofovea                       | - -Critolaus                       | - -Dactylothele                       | - -Dystactotylos                       | - -Hylonomoipos                       | - -Konothele                       | - -Leuropezos                       | - -Mantonipatus                       | - -Ooperipatus                       | - -Phallocephale                       | - -Planipapillus                       | - -Ruhbergia                       | - -Tetrameraden                       | - -Vescerro                       | - -Wambalana                       | - -Wambalana                       |-n. N.
                        | | - -Regimitra                       | | - -Anoplokaros                       | |-n. N.
                           | - -Aethrikos                          | - -Sphenoparme

The molecular-genetic and from the Retrovikarianzanalyse of derived realizations cover themselves only very inaccurately, on both areas thus further research need insists.

Literature

• D. A. Briscoe, N. N. Tait, Allozyme evidence for extensive and ancient radiation in Australia Onychophora, Zoological journal OF the Linnean Society, 114, 1995, Page 91
• D. A. Briscoe, N. N. Tait, Gene TIC deviation within new Zealand Onychophora and their relationships ton the Australian fauna, Zoological journal OF the Linnean Society, 114, 1995, Page 103
• A. L. Reid, Review OF the Peripatopsidae (Onychophora) in Australia, with COMMENT on Peripatopsid Relationships, Invertebrate Taxonomy, 10, 1996, 663
• N. N. Tait, J. M. Norman, Novel mating behaviour in Florelliceps stutchburyae towards. Nov., FR. November. (Onychophora, Peripatopsidae) from Australia, Journal OF Zoology, 253, 2001, Page 301