Oroperipatus tiputini: A new species of Velvet Worm from the Ecuadorian Amazon.

Velvet Worms, Onychophora, are a unique group of elongate, soft bodied, many legged  Animals, given phylum status and considered to be among the closest living relatives to the Arthropods. They are currently the only known phylum of Animals known entirely from terrestrial species, both living and fossil, although they may be related to the Lobopodans, an entirely marine group known only from Early Palaeozoic fossils. 

The 230 living Velvet Worm species are divided into two groups, the Peripatidae, found in the tropics of Central and South America, the Antilles Islands, Gabon, India, and Southeast Asia, and the Peripatopsidae, found in Chile, South Africa, Papua New Guinea, Australia, and New Zealand. All South American members of the Peripatidae are placed within a single clade, the Neopatida, which is further divided into two lineages, the 'Andean' genus Oroperipatus, and the 'Caribbean' lineage, comprising all other genera.

In a paper published in the journal Zoosystematics and Evolution on  14 June 2024, Jorge Montalvo-Salazar of  the Instituto de Biodiversidad Tropical at the Universidad San Francisco de Quito, and the Laboratorio de Zoología Terrestre at the Quito Museo de Zoología, Lorena Bejarano and Alfredo Valarezo of the Instituto de Energía y Materiales at the Universidad San Francisco de Quito, and Diego Cisneros-Heredia, also of the Instituto de Biodiversidad Tropical at the Universidad San Francisco de Quito, and the Laboratorio de Zoología Terrestre at the Quito Museo de Zoología, and of the Estación de Biodiversidad Tiputini of the Universidad San Francisco de Quito, and the Ecuadorian Instituto Nacional de Biodiversidad, describe a new species of Oroperipatus from the Amazonian lowlands of Ecuador.

The new species is described from five male, three female, and three juvenile specimens collected in the vacinity of the Tiputini Biodiversity Station of the Universidad San Francisco de Quito in Orellana Province, Ecuador, between 2001 and 2023, as  well as one youngling, which one of the female specimens gave birth to in captivity. The new species is named Oroperipatus tiputini, in reference to the location where it was discovered. 

Oroperipatus tiputini, adult female holotype (ZSFQ-i8248) and youngling paratype (ZSFQ-17794) a few days after being born. Pedro Peñaherrera in Montalvo-Salazar et al. (2024).

Adult female specimens of Oroperipatus tiputini very between 46 and 65.3 mm in length, while the adult males are smaller at 22.7 to 39.8 mm. Females have between 37 and 40 pairs of legs, while the males have between 34 and 37, although one male specimen had a different number of legs on each side, with 35 legs on the right and 36 legs on the left. The species shows considable colour variation, with one adult male being a light brown colour with a faint rhomboid pattern, two adult males and one adult female being brown with orange diamonds, and another female (the one which produced a youngling) being a plain dark orange colour. The youngling itself was yellowish with a diamond pattern. All specimens were darked on their heads and antenae,  had orange or brown legs, and a distinctive white band on the head.

Oroperipatus tiputini, adult male paratype, ZSFQ-i8270. Pedro Peñaherrera in Montalvo-Salazar et al. (2024).

Most specimens of Oroperipatus tiputini were found on small herbaceous Plants within old growth, closed canopy upland forests around the Tiputini Biodiversity Station. Other specimens were found in leaf litter, or on the butress roots of trees to a height of about 70 cm above the ground. One specimen was found in a Bromiliad. The Worms were more active at night. 

Oroperipatus tiputini, adult male paratype, ZSFQ-i5151. Diego Cisneros-Heredia in Montalvo-Salazar et al. (2024).

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Ovatiovermis cribratus: A Luolishanid Lobopodian from the Middle Cambrian Burgess Shale Lagerstätte of British Columbia.

The Arthropods are grouped together with two other living phyla, the Onychophorans (Velvet Worms) and Tardgrades to form a higher group called the Panarthropods, a group of limbed organisms thought to have evolved from a single Worm-like ancestor. The early origins of these groups are less than clear however; a variety of other Panarthropod groups, such as the Anomalocarids, which may have been early Arthropods, and the Lobopodians, which are thought to have been ancestral to the modern Onychophorans.

In a paper published in the journal BMC Evolutionary Biology on 31 January 2017, Jean-Bernard Caron of the Department of Natural History (Palaeobiology Section) at the Royal Ontario Museum, and the Department of Ecology and Evolutionary Biology and Department of Earth Sciences at the University of Toronto, and Cédric Aria, also of the Department of Ecology and Evolutionary Biology at the University of Toronto, describe a new species of Lobopodian from the Middle Camrian Burgess Shale Lagerstätte of Walcott Quarry in British Columbia.

The new species is named Ovatiovermis cribratus, where 'Ovatiovermis' means 'ovation-Worm' in reference to the presumed life posture of the species, standing on its hindlimbs with its forelimbs waving in the air, and 'cribratus' means 'to sieve'. The species is described from two specimens, one 30 mm in length and the other 12 mm. The species shows diffentiation of the limbs with short hind limbs and longer forelimbs covered in elongate claws, which Caron and Aria interpret as having been used for filter feeding (standing on hindimbs and sieving the water with upraised forelimbs).

Ovatiovermis cribratus from the Burgess Shale, Royal Ontario Museum (ROM) 52707: (a–e, i, j) part, (g, h) counterpart, (f) reconstructed death pose. Close-ups indicated by white rectangles. (a, b) full specimen under direct (a) and polarized (b) lighting conditions. (c–e) superposed elemental maps of carbon (red) and calcium (purple) before preparation of the 8th left lobopod (lL8—see a). The lighter colours represent higher concentrations of elements: parts of the gut, proboscis, pharyngeal area and claws are preserved in carbon whereas the rest of the body is preserved in calcium. (g–j) details of the anterior part of the body showing internal organs in Lobopods (g), pair of visual organs (g, h), spinules and bifid claws (g, i, j). Digital single-lens reflex (DSLR) images taken using direct light (a, i, j) and cross-polarized light (b, g, h), all under dry conditions except (b, g and h). A, annulations; C, claw; Ds, dark stain; E, “eye” (visual organ); G, gut; H, head; I, internal organ; L, lobopod (l, left; r, right; x,y, lobopod position); Lu; foregut lumen; M, mouth; Pr, proboscis; S, spinules. Scale bars: 5 mm (a–c, g, i), 1 mm (e, d, h, j). Caron & Aria (2017).

Previous reconstructions of the phylogeny of Cambrian Lobopodians has shown the presence of two distinct groups, the armoured Hallucigenians and the unamoured Luolishanids, which show greater limb diferentiation and are thought to have been ancstral to the modern Velvet Worms. A phylogenetic reconstruction made by Caron and Aria including Ovatiovermis cribratus placed the new species firmly within the Luolishanid group, but also suggested that both groups in fact split off from the other Panarthropods before the split between Tardigrades, Velvet Worms and Arthropods, suggesting the common ancestor of these groups was in fact Lobopodian-like.

Artistic interpretation of Ovatiovermis cribratus as a living animal. Danielle Dufault in  Caron & Aria (2017).

The closet relatives of the Panarthropods are thought to be the Nematode, Priapulid and Palaeoscorid Worms, with the common ancestor of the Panarthropods thought to be something similar to Paucipodia, a Loboopd from the Early Cambrian Chengjiang Lagerstätte of China which resembles a Nematode with legs. However, while Caron and Aria's phylogeny did recover Paucipodia as close to the common ancestor of the living Arthopods, Velvet Worms and Tardigrades, it also suggests that the Luolishanids split from the other groups before the Hallucigenians, and that the Hallucigenians split off before Paucipodia, making the biology of the earliest Panarthropodian ancestor more uncertain than before.

 Consensus tree of a Bayesian phylogenetic analysis of our morphological matrix composed of 38 taxa and 59 characters (four runs, 10,000,000 generations, burn-in fraction: 0.20). Total-group Onychophorans highlighted in green, Hallucigeniids in blue and Luolishaniids in red. Microdictyon and Facivermis are considered potentially included within Hallucigeniids and Luolishaniids, respectively, which is denoted by the coloured dashed lines. Numbers above branches represent posterior probabilities. Caron & Aria (2017).

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Antennipatus montceauensis: A Velvet Worm from the Late Carboniferous of France.

Velvet Worms, Onychophora, are curious caterpillar-like organisms found in the tropics and temperate regions of the Southern Hemisphere. They show external segmentation, but are not internally segmented, have a soft cuticle rather that an exoskeleton, have non-segmented paired appendages, and thick, non-segmented paired antennae. Velvet Worms hunt Invertebrate prey, which they immobilize with a sticky slime fired from special organs behind the antennae, the slime papillae. There are two living families of Onychophora, the Peripatopsidae, found in Australia, New Zealand, South Africa and Chile, and the Peripatidae, found in West Africa, Southeast Asia, and the American Tropics. All known extant species are terrestrial, the only known Animal Phylum for which this is true, with their closest relatives being the Arthropods and Tardigrades. Phylogenetic analyses have shown the living Velvet Worms to be descended from the Lobopodians, a curious group of entirely marine soft-bodied animals known from a number of Cambrian locations, however how the Cambrian marine Lobopodians gave rise to the Modern terrestrial Velvet Worms is somewhat of a mystery, as there are almost no fossil specimens known for the intervening period; Cretoperipatus burmiticus, from Late Cretaceous Burmese Amber is a terrestrial form hard to distinguish from Modern Velvet Worms, Helenodora inopinata, from the Carboniferous Francis Creek Shale of Illinois is apparently an Onychophoran and a descendent of the Cambrian Lobophorians, but is not thought to be ancestral to, or closely related to, the living Velvet Worms, while all other putative post-Silurian  Onychophoran fossils have now been excluded from the group.

In a paper published in the journal Invertebrate Biology on 2 August 2016, Russell Garwood of the School of Earth, Atmospheric and Environmental Sciences at The University of Manchester and the Department of EarthSciences at The Natural History Museum, Gregory Edgecombe, also of the Department of Earth Sciences at The Natural History Museum, Sylvain Charbonnier of the Département Histoire de la Terre at the Muséum national d’Histoire naturelle, Dominique Chabard and Daniel Sotty of the Muséum d’Histoire naturelle d’Autun, and Gonzalo Giribet of the Museum of Comparative Zoology and Department of Organismic and Evolutionary Biology at Harvard University and the Department of Life Sciences at The Natural History Museum. Describe a new species of Onychophoran from the Late Carboniferous Montceau-les-Mines Lagerstätte of France. 

Putative Onychophorans from these deposits have been recorded for over thirty years, however poor preservation of the material has prevented formal description of the material until now. Garwood et al. were able to supplement the light microscopy usually used to examine fossils of this type, with more modern methods, such as computerized tomography and digitally enhanced visualization.

The new species is named Antennipatus montceauensis, where 'Antennipatus' refers to the Antennae of the specimens, which is very similar to that of modern Velvet Worms, suggesting a close relationship (the suffix -patus is commonly used to describe modern genera within the group), and 'montceauensis' means 'coming from Montceau'. The specimens are essentially similar to modern Velvet Worms, including having what appear to be slime papillae. However it was not possible to place these Carboniferous Worms in either of the modern families, as none of the features which can be used to separate these group were (or were likely to be) preserved. This means it is impossible to say whether they belong to one of the two living families (which molecular clock data suggests separated in the Devonian), an unknown group sharing a common ancestor or a group which branched off before the divergence of the modern Onychophoran families.

The Carboniferous Onychophoran Antennipatus montceauensis from the Stephanian Montceau-les-Mines Lagerstätte, France. (A–C). First specimen, showing the head, including an antenna and five anterior segments of the trunk. Shown in light photograph (A), as rendered image from CT data employing low-angle lighting (B), and as a rendered image using a multicolored lighting rig (C). (D–E). Second specimen, showing the same region of the organism, but with one set of lobopods as protrusions rather than depressions. Shown as light photograph (D), lowangle lighting render (E), and multicolored lighting render (F). (G). An enlargement of (D), showing the antenna, a possible mouth, and slime papilla. (H). An SEM image of the trunk showing large primary papillae and ridges demarking plicae. (I.) A photomicrograph of the anterior of the fossil showing the left slime papilla, possible mouth, and antenna. (J). A photomicrograph of the trunk, showing the plicae and several well preserved lobopods. a, antenna; lb1–lb5, lobopods 1–5; m?, putative mouth; sp, slime papilla. Scales: A–G, 10 mm; H, 1 mm; I–J, 2 mm. Garwood et al. (2016).

  

The Montceau-les-Mines Lagerstätte is believed to have formed in and around a river delta flowing into a freshwater lake. The site produces in situ woody fossils (i.e. the trunks and roots of trees preserved in the position where they grew, interspersed with fluvial (river) and lucastrine (lake) sedments. There is no influence for any marine influence on the site. Therefore Antennipatus montceauensis could potentially have inhabbited a terrestrial environment similar to that favoured by modern Velvet Worms, or coud possibly have inhabited fresh water, a habitat no other Onychophoran, living or fossil, is known to have inhabited, but which is a plausible step between the fully marine habbit of ancient members of the group and the entirely terrestrial habitat favoured by moden Velvet Worms.

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Insect nymphs from the Carboniferous Montceau-les-Mines Lagerstätte of France. The majority of modern Insects have a distinct larval stage, that does not resemble the adult and which then metamorphoses into the adult form upon reaching maturity. This is one of the reasons for the...

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