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Velvet Worms
Onychophora (from , , "claws"; and , , "to carry"), commonly known as velvet worms (for their velvety texture and somewhat wormlike appearance) or more ambiguously as peripatus (after the first described genus, '' Peripatus''), is a phylum of elongate, soft-bodied, many-legged animals. In appearance they have variously been compared to worms with legs, caterpillars, and slugs. They prey upon other invertebrates, which they catch by ejecting an adhesive slime. Approximately 200 species of velvet worms have been described, although the true number is likely to be much greater. The two extant families of velvet worms are Peripatidae and Peripatopsidae. They show a peculiar distribution, with the peripatids being predominantly equatorial and tropical, while the peripatopsids are all found south of the equator. It is the only phylum within Animalia that is wholly endemic to terrestrial environments, at least among extant members. Velvet worms are generally considered close relative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oroperipatus
''Oroperipatus'' is a genus of Neotropical Onychophora, velvet worms in the family Peripatidae. Species in this genus are found in South America west of the Andes and in Mexico. This genus is viviparous, with mothers supplying nourishment to their embryos through a placenta. Description Velvet worms in this genus can have as few as 22 pairs of legs (in ''Oroperipatus omeyrus, O. omeyrus'') or as many as 40 leg pairs (in ''Oroperipatus bluntschli, O. bluntschli'', ''Oroperipatus weyrauchi, O. weyrauchi'', and ''Oroperipatus tiputini, O. tiputini''). Species in this genus have from four to seven distal foot papillae, with two or more on the anterior part of the foot and two or more on the posterior part of the foot. This genus also features a nephridial tubercle on the fourth and fifth leg pairs inserted into a complete third spinous pad. Species The genus contains the following species: * ''Oroperipatus balzani'' (Camerano, 1897) * ''Oroperipatus belli'' (Bouvier, 1904) * ''Or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panarthropoda
Panarthropoda is a clade comprising the greatest diversity of animal groups. It contains the extant phyla Arthropoda (Euarthropoda), Tardigrada (water bears) and Onychophora (velvet worms), although the precise relationships among these remained uncertain according to studies published in 2023 and 2024. Panarthropods also include extinct marine legged worms known as lobopodians (" Lobopodia"), a paraphyletic group where the last common ancestor and basal members ( stem-group) of each extant panarthropod phylum are thought to have risen. However the term "Lobopodia" is sometimes expanded to include tardigrades and onychophorans as well. Common characteristics of the Panarthropoda include a segmented body, paired ladder-like ventral nervous system, and the presence of paired appendages correlated with body segments. Taxonomy Not all studies support the monophyly of Panarthropoda, but most do, including neuroanatomical, phylogenomic and palaeontological studies. At l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different developmental origin, structure and chemical composition. The adjective cutaneous means "of the skin" (from Latin ''cutis'' 'skin'). In mammals, the skin is an organ of the integumentary system made up of multiple layers of ectodermal tissue and guards the underlying muscles, bones, ligaments, and internal organs. Skin of a different nature exists in amphibians, reptiles, and birds. Skin (including cutaneous and subcutaneous tissues) plays crucial roles in formation, structure, and function of extraskeletal apparatus such as horns of bovids (e.g., cattle) and rhinos, cervids' antlers, giraffids' ossicones, armadillos' osteoderm, and os penis/ os clitoris. All mammals have some hair on their skin, even marine mammals like whales, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plicatoperipatus Jamaicensis
''Plicatoperipatus'' is a monospecific genus of velvet worm containing the single species ''Plicatoperipatus jamaicensis''. It is endemic to Jamaica. Females of this species can have as many as 43 pairs of legs, the maximum number found in the phylum Onychophora. In a large sample collected in 1988, however, females ranged from 35 to 39 leg pairs, with 37 as the mean and the most common number, and males ranged from 31 to 37 leg pairs, with 35 as the mean and the most common number. This species ranges from 25 mm to 65 mm in length. In the 1988 sample, the mean length for males was 33 mm, and the mean length for mature females was 51 mm. This species is viviparous, with mothers supplying nourishment to their embryos through a placenta. Conservation This species is listed as Near Threatened by the IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mongeperipatus Solorzanoi
''Mongeperipatus solorzanoi'', also known as Solórzano's velvet worm, is a species of velvet worm in the family Peripatidae. This species is the largest known velvet worm, reaching 22 cm (8.7 in.) in length. This velvet worm is found in the Caribbean coastal forest of Costa Rica. Discovery This species was first described in 2010 by the biologists Bernal Morera-Brenes and Julián Monge-Nájera based on fourteen female specimens and two male specimens. These specimens include a female holotype found by the Costa Rican herpetologist Alejandro Solórzano in Guayacán de Siquirres in Costa Rica in 1996, four young paratypes born to the holotype soon after her capture, and other paratypes collected in 2000. The specific name ''solorzanoi'' is in honor of Solórzano, who discovered the species. The holotype is deposited in the Museo de Zoología de la Universidad de Costa Rica in San José, Costa Rica. Taxonomy Morera-Brenes and Monge-Nájera first described this species i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ooperipatellus Nanus
''Ooperipatellus nanus'' is a species of velvet worm in the family Peripatopsidae. This species is endemic to New Zealand and is found in the South Island. Taxonomy This species was first described by Hilke Ruhberg in 1985. Description ''Ooperipatellus nanus'' is a small species of velvet worm that grows to a length of approximately 10 mm. This species is tan or brown in color on its back but yellow on its underside. It is oviparous and has 13 pairs of legs, which is the minimum number found in the phylum Onychophora. Distribution ''Ooperipatellus nanus'' has only been found in Southland, in the Takitimu Mountains. Life cycle This species produce young by laying eggs from which the young subsequently hatch. Host species ''Ooperipatellus nanus'' are found mainly in rotting beech logs. Conservation status This species has been classified as having the "At Risk, Naturally Uncommon" with the qualifier of "One Location" conservation status under the New Zealand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appendage
An appendage (or outgrowth) is an external body part or natural prolongation that protrudes from an organism's body such as an arm or a leg. Protrusions from single-celled bacteria and archaea are known as cell-surface appendages or surface appendages. In many kinds of eukaryotic cells, the protrusions are known as membrane protrusions or cell appendages (examples include microvilli and cilia). Types in animals In arthropods, an appendage refers to any of the homologous body parts that may extend from a body segment, including antennae, mouthparts (including mandibles, maxillae and maxillipeds), gills, locomotor legs ( pereiopods for walking, and pleopods for swimming), sexual organs ( gonopods), and parts of the tail (uropods). Typically, each body segment carries one pair of appendages. An appendage which is modified to assist in feeding is known as a maxilliped or gnathopod. In annelids lateral protrusions from the body are called parapodia. In echinoderms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cylinder (geometry)
A cylinder () has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base. A cylinder may also be defined as an infinite curvilinear surface in various modern branches of geometry and topology. The shift in the basic meaning—solid versus surface (as in a solid ball versus sphere surface)—has created some ambiguity with terminology. The two concepts may be distinguished by referring to solid cylinders and cylindrical surfaces. In the literature the unadorned term "cylinder" could refer to either of these or to an even more specialized object, the '' right circular cylinder''. Types The definitions and results in this section are taken from the 1913 text ''Plane and Solid Geometry'' by George A. Wentworth and David Eugene Smith . A ' is a surface consisting of all the points on all the lines which are parallel to a given line and which pass through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Segmentation (biology)
Segmentation in biology is the division of some animal and plant body plans into a linear series of repetitive segments that may or may not be interconnected to each other. This article focuses on the segmentation of animal body plans, specifically using the examples of the taxa Arthropoda, Chordata, and Annelida. These three groups form segments by using a "growth zone" to direct and define the segments. While all three have a generally segmented body plan and use a growth zone, they use different mechanisms for generating this patterning. Even within these groups, different organisms have different mechanisms for segmenting the body. Segmentation of the body plan is important for allowing free movement and development of certain body parts. It also allows for regeneration in specific individuals. Definition Segmentation is a difficult process to satisfactorily define. Many taxa (for example the molluscs) have some form of serial repetition in their units but are not conventi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 juvenile that is at least metabolically independent. This is opposed to oviparity, where the embryos develop independently outside the mother in eggs until they are developed enough to break out as hatchlings; and ovoviviparity, where the embryos are developed in eggs that remain carried inside the mother's body until the hatchlings emerge from the mother as juveniles, similar to a live birth. Etymology The term "viviparity" and its adjective form "viviparous" both derive from the Latin ''vivus'', meaning "living"; and ''pario'', meaning "give birth to". Reproductive mode Five modes of reproduction have been differentiated in animals based on relations between zygote and parents. The five include two nonviviparous modes: ovulipari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mating
In biology, mating is the pairing of either opposite-sex or hermaphroditic organisms for the purposes of sexual reproduction. ''Fertilization'' is the fusion of two gametes. '' Copulation'' is the union of the sex organs of two sexually reproducing animals for insemination and subsequent internal fertilization. Mating may also lead to external fertilization, as seen in amphibians, fishes and plants. For most species, mating is between two individuals of opposite sexes. However, for some hermaphroditic species, copulation is not required because the parent organism is capable of self-fertilization (autogamy); for example, banana slugs. The term ''mating'' is also applied to related processes in bacteria, archaea and viruses. Mating in these cases involves the pairing of individuals, accompanied by the pairing of their homologous chromosomes and then exchange of genomic information leading to formation of recombinant progeny (see mating systems). Animals For animals ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and used this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. Modern zoology has its origins during the Renaissance and early modern period, with Carl Linnaeus, Antonie van Leeuwenhoek, Robert Hooke, Charles Darwin, Gregor Mendel a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
