All velvet worms are exclusively terrestrial and can be found in humid tropical rainforests. They favor damp leaf litter, rotting wood, undersides of stones and other dark, moist environments. Some species even prefer to burrow underneath soil. These habitats are preferred as the velvet worm respirates through open holes on the sides of their bodies, leaving them susceptible to water loss. (Barquero-Gonzalez, et al., 2018; Costa and Giribet, 2021; Mayer, et al., 2015)
Velvet worms are most closely related to arthropods and tardigrades, and are some of the oldest living taxa on Earth, with lineages remaining nearly unchanged for around 500 million years. Each of the two velvet worm families has a distinct lineage based off of where they were positioned when supercontinent Godwana fragmented and separated, Peripatidae being in the Neotropics and Peripatopsidae being in Australia and Southern Asia. Taxonomic analysis of this cryptic genus has been difficult due to similar morphological characteristics across the taxa and intraspecific variation, but molecular analysis is proving that is a more genetically diverse group than we first thought. Analysis of RNA sequences is revealing the presence of rich cryptic variation amongst previously described species of . (Oliviera, et al., 2011; Smith, 2016)
Members of Onychophorans, and there are many complicated gaps in the morphological study of this genus, such as an overall lack of defining characteristics. species and all other velvet worms across the phylum Onychophora tend to look extremely similar and are nearly impossible to differentiate without DNA testing. (Bates, 2014; Costa, et al., 2018; Mayer, et al., 2015)have hydrostatic skeletons covered with an external cuticle that is lined with numerous sensitive papillae to help them sense their environments and give them a 'velvety' appearance. They respirate through un-branched tracheal holes that line the sides of their bodies. They may have anywhere between 20 and 40 pairs of legs, which end in claws. On their heads, they have a pair of antennae and two oral papillae that help them capture their prey, along with a set of fangs. The perimeter of their mouths can be lined with chemoreceptors. The physical appearance of species found within is consistent with most other
development has not been described in literature.
Mating between velvet worms has rarely been seen, and has only been observed in a few species. All currently known species of velvet worm reproduce sexually, with the exception of Epiperipatus imthurni - no males have even been described in this species, and reproduction is done by parthogenesis. Within the family Peripatidae, all species are viviparous. The male usually deposits a spermatophore inside of the female, where the eggs will develop and hatch. The young emerge as fully formed, smaller versions of the adult worm. (Bates, 2014)
The reproductive cycle and breeding season ofhave not been described in literature.
As soon as the worms are hatched and subsequently birthed, the fully formed young are able to exist on their own, and require no extra parental care. (Bates, 2014)
The lifespan of (Mayer, et al., 2015)has not been described in literature. In general, velvet worms can be expected to live up to 6 years in the wild, and their potential lifespan in captivity is unknown.
Velvet worms are nocturnal and leave their burrows at night to forage for small invertebrates. They are very cryptic and only leave their burrows to hunt. They are ambush predators and hunt by capturing prey in a sticky, protein-rich liquid that they expel from oral tubes near their mouths. Epiperipatus sp., in Costa Rica. The species was found to be most active during the dry season of December-April and were rarely seen on rainy nights. The species was also more active on dark nights absent of moonlight. (Barquero-Gonzalez, et al., 2018)behavior has only been recorded in one undescribed species,
Communication and social hierarchy between velvet worms has been described in other families of velvet worms, but there is no published information on (Mayer, et al., 2015)specifically. Given the fact that their skin is lined with tiny, sensitive papillae, it is assumed that, like other velvet worms, communicate with and collect information about other individuals by rubbing their papillae and/or antennae against each other.
Like all other velvet worms, (Mayer, et al., 2015)may be predated on by larger centipedes, spiders and birds. However, this is not very common as these animals spend almost all of their time hiding. Though mainly used for prey capture, the velvet worm may also use the secretions from its oral slime glands to ward off predators.
Velvet worms have recently begun to enter the exotic pet trade. Epiperipatus barbadensis is one of the most common velvet worm species kept in captivity. Velvet worm husbandry can be compared to poison dart frog husbandry, and while difficult for the average pet owner, can be an intriguing and unique addition to an experienced exotic pet owner's collection. (Barquero-Gonzalez, et al., 2016; Barquero-Gonzalez, et al., 2018)
There are no known adverse effects ofon humans.
Evaluating the conservation status of Epiperipatus isthmicola is one example, as all of its known habitat is covered by urban development. Despite this, no described action is being taken to protect velvet worms at this time. (Barquero-Gonzalez, et al., 2016; Costa, et al., 2018; Oliviera, et al., 2012)is nearly impossible due to conflicting and often incomplete descriptions of whether newly described species are valid or not, but it is often assumed that many new species are threatened or endangered because of their small, fragmented populations.
Thanks to molecular analysis, more species of Onychophora, and the number of species in the genus is continuing to grow.have been discovered in the past decade than any of the other families in
Emma Long (author), Colorado State University, Audrey Bowman (editor), Colorado State University.
living in the southern part of the New World. In other words, Central and South America.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
uses smells or other chemicals to communicate
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
An animal that eats mainly insects or spiders.
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
the business of buying and selling animals for people to keep in their homes as pets.
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
Living on the ground.
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
young are relatively well-developed when born
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