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-Colossendeis wilsoni Calman, 1915. (MNA: 1083): A, dorsal view of body; B, lateral view of body; C, distal segments of palp; D, strigilis; E, third leg of right side; F, distal leg segments.
Source publication
The pycnogonid fauna of the genus Colossendeis collected during the Italica XIX cruise to Victoria Land (Ross Sea, Antarctica) was studied. A total of 19 specimens of six species were collected: Colossendeis australis (6), C. wilsoni (3), C. scotti (2), C. robusta (3), C. lilliei (2) and C. megalonyx (3). In the present contribution the observed va...
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Phylogenetic analyses of molecular sequence data obtained from the holotype of Marmosa reginaThomas, 1898, together with a reassessment of its morphological characters indicate that this species does not belong to the subgenus Micoureus as previously believed. Instead, both molecular and phenotypic data are consistent with the hypothesis that M. re...
Citations
... However, this last synonym is contested by other authors (e.g. Cano-Sánchez and López-González 2007;Turpaeva and Rajsky 2013). Indirectly, Krabbe et al. (2010) corroborated the latter interpretation in their study on the phylogenetic position of C. megalonyx Hoek, 1881 within the genus Colossendeis. ...
... Indirectly, Krabbe et al. (2010) corroborated the latter interpretation in their study on the phylogenetic position of C. megalonyx Hoek, 1881 within the genus Colossendeis. Another controversial taxonomic status is that of C. glacialis Hodgson, 1907 considered a junior synonym of C. robusta by some authors (Fry and Hedgpeth 1969;Child 1995) but considered a separate species by others (Pushkin 1993;Stiboy-Risch 1993;Cano-Sánchez and López-González 2007;Munilla and Soler-Membrives 2009;Turpaeva and Rajsky 2013;Bamber et al. 2022). Recently molecular or combined molecularmorphological studies have confirmed that C. robusta and C. glacialis must be considered distinct species (Dietz et al. 2015a;Dietz et al. 2019). ...
... The specimens of C. australis examined in this study agree with the original description (Hodgson 1907) and subsequent authors (Bouvier 1913;Calman 1915;Fry and Hedgpeth 1969;Pushkin 1993;Child 1995; -González 2007). This species is similar to C. speudochelata Pushkin, 1993. ...
In this paper, specimens belonging to the pycnogonid genus Colossendeis Jarzynsky, 1870 collected during the Antarctic Polarstern XXIII/8 cruise (November 23, 2006, to January 30, 2007) were studied. In this collection, the following thirteen species have been identified, two of them being proposed as new species: Colossendeis frigida Hodgson, 1907, C. megalonyx Hoek, 1881, C. wilsoni Calman, 1915, C. engirmatica Turpaeva, 1974, C. arundorostris Fry & Hedgpeth, 1969, C. scotti Calman, 1915, C. lilliei Calman, 1915, C. drakei Calman, 1915, C. glacialis Hodgson, 1907, C. australis Hodgson, 1907, C. tortipalpis Gordon, 1932, C. pseudofrigida sp. nov., and C. bamberi sp. nov. All species are diagnosed and their taxonomic status discussed. C. frigida , C. engirmatica , and C. arundorostris extend their known depth range. C. arundorostris has been found for the first time outside the Ross Sea. The finding of C. engirmatica represents the first record after its original description. The new species are described, illustrated, and compared with their closest congeners. Finally, we carried out a cluster analysis (Bray-Curtis similarity index) based on a data-matrix of 49 Antarctic and Sub-Antarctic Colossendeis species and 26 morphological characters.
... Only the long proboscis, palp article 8 shorter than articles 9 and 10 and a tarsus longer than the propodus remain stable amongst all examined specimens (Child 1995a). Variable characters are the shape and size of the ocular tubercle (elevated or short, conical or rounded), the occurrence of eyes (similar in size or larger anteriorly, well pigmented, white or even absent), the size of the proboscis (equal to, or longer than the trunk) and the size of the legs (either the femur or the tibia represent the longest article) (Child 1995a(Child , 1998bCano-Sanchez and López-González 2007). ...
Five species were identified in the studied collection: Colossendeis megalonyx Hoek, 1881, first record for Uruguay, Ascorhynchus corderoi du Bois-Reymond Marcus, 1952 and Pallenopsis candidoi Mello-Leitão, 1949, with extended ranges, Pallenopsis patagonica (Hoek, 1881), a species complex recently analysed with molecular data and Ammothea tetrapoda, recorded previously for Uruguayan waters. Our study clarifies records based on morphology, provides new data on distributions and species ranges and correlates species with ecological conditions.
... Child recorded great variation in size, and in morphometric relationships between proboscis, femur, and tibia. These considerations, as well as those made below for C. geoffroyi, highlight the need for a revision of Antarctic and Subantarctic species of Colossendeis (Cano & López-González 2007;Krabbe et al. 2010). ...
Records of pycnogonids from Uruguayan waters (south-western Atlantic) include 26 species cited from precise locations, and at least five other species based on unconfirmed records. Nearly half of the species in that fauna belong to the genus Nymphon (12 spp.). Most species (22) come from deep-water and were recorded and described by C. A. Child. Of these, at least twelve species have an extended Antarctic and Subantarctic distribution, showing the influence of these cold waters in the area; three others have a wide deep-sea distribution pattern. Five species are known only from the lower slope and abyssal basin off La plata river: Mimipallene Atlantis and four species of Nymphon. Records from coastal and shelf areas (four species) are poorly documented and should be the focus of future research. Of these, Colossendeis geoffroyi is considered endemic in the Southwest Atlantic between 34ºS and 40ºS, but presents clear Antarctic affinities. A small-sized species living in shallow waters, Pycnogonum cessaci, is here considered as cryptogenic.
... Most are relatively small (with leg spans of less than a centimeter) and have a very thin and small body consisting of a four-segmented cephalothorax bearing four pairs of excessively long and slender legs [175]. However, a few arctic species -such as the members of the genus Colossendeis Jarzinsky, 1870 (Pantopoda: Colossendeidae) -are comparatively enormous and have leg spans of four to five centimeters [176]. ...
Drug discovery and development programs have historically mainly focused on plants with medicinal properties and the extensive knowledge of traditional healers about these plants. More recently, the vast array of marine invertebrates and insects throughout the world have been recognized as additional sources for identifying unusual lead compounds to obtain structurally novel and mechanistically unique therapeutics. The results from these efforts are encouraging and have yielded a number of clinically useful drugs. However, many arthropods other than insects-such as spiders, scorpions, horseshoe crabs, sea spiders, centipedes, and millipedes-also produce hundreds of bioactive substances in their venom that may become useful in the clinic. Many of these chemicals are defensive and predatory weapons of these creatures and have been refined during millions of years of evolution to rapidly and with high specificity and high affinity shut down critical molecular targets in prey and predators. Exploration of these compounds may lead to the development of, among others, novel drugs for treating diseases caused by abnormalities in humans in the same (evolutionary conserved) molecular targets such as erectyle dysfunction, botulism, and autoimmune disorders, as well as the identification of novel antineoplastic, antimicrobial, and antiparasitic compounds. This paper addresses the importance of bioactive compounds from spiders, scorpions, horseshoe crabs, sea spiders, centipedes, and millipedes to these advances.
... Cano and López-Gonzalez [22] discussed the 10-or 11articled nature of the ovigers in the Colossendeis species based on their similarities with the basal parts of palps. If a 10-articled palp is considered, an 11-articled oviger should not be rejected; both considerations seem to be linked. ...
... In the case of the oviger structure, a 10-articled condition (plus a terminal claw) is accepted for Colossendeidae species, but the ovigers have an indistinct suture line between the cephalon and the basal part of the ovigers (see [22]: Fig. 14; and Fig. 1 in this paper). Cano and López-González [22] discussed the presence of four short oviger basal articles or an oviger-bearing process followed by three short articles, as is generally accepted in the literature. ...
... In the case of the oviger structure, a 10-articled condition (plus a terminal claw) is accepted for Colossendeidae species, but the ovigers have an indistinct suture line between the cephalon and the basal part of the ovigers (see [22]: Fig. 14; and Fig. 1 in this paper). Cano and López-González [22] discussed the presence of four short oviger basal articles or an oviger-bearing process followed by three short articles, as is generally accepted in the literature. These authors considered the possibility of an 11-articled condition in Colossendeis ovigers by including this basal part instead of the 10-articled condition described in previous literature. ...
Selected sea spider specimens of Antarctic Colossendeis species collected during the Italica XIX cruise and the Polarstern cruise ANT XXIII/8 were examined to provide new information about the external and internal anatomy of the basal parts of the palps and ovigers. The presence and insertion of the muscle bands, as well as the arthrodial membrane are illustrated and discussed. The results obtained in this study show that the basal parts of the palps and ovigers have a similar internal structure. This is in agreement with the currently established 10-articled status for the ovigers (the basal element is not considered an article). Despite the currently established 10-articled status for the palps, our results suggest that the palp should be considered as being 9-articled.
Keywords
Sea spiders Basal articulation Scanning electron microscopy Light microscopy Musculature
... The morphology of Colossendeis species mostly re sembles that of other Pycnogonida (kinG 1973;arnaud & BaMBer 1987;Child 1995;aranGo 2002;aranGo & Wheeler 2007;Cano & loPez-Gonzalez 2007) except that adults lack chelifores. The trunk, comprising most of the body, consists of cephalic and legbearing segments. ...
... In other pycnogonids, the ovigera are used by the male to carry the eggs, however, in Colossendeis no eggcarrying males have been found, and they probably serve as cleaning appendages (kinG 1973;Bain 2003). The last four ovigeral articles bear a complex arrangement of spines and together form the strigilis, the morphology of which can be diagnostic for particular species (Cano & loPez-Gonzalez 2007). The three postcephalic legbearing segments are fused. ...
... The (mostly) larger species C. robusta is argued to be described based on more fully grown individuals. Other authors disagree with the synonymization of C. glacialis and C. robusta and continue to treat both spe cies as being distinct (Pushkin 1988;stiBoy-risCh 1993;Cano & loPez-Gonzalez 2007). Claimed differences between the two species are summarized in Table 1. ...
Colossendeis robusta Hoek, 1881, originally described from the Kerguelen shelf, is considered as one of the most widespread Antarctic pycnogonids. However, the taxonomic status of this and similar species has long been unclear, as synonymy of C. glacialis Hodgson, 1907 and several other species with C. robusta has been proposed. Here we test the synonymy of C. robusta and C. glacialis with two independent molecular markers as well as comprehensive morphometric measurements and SEM data of the ovigeral spine configuration. We show that C. robusta and C. glacialis are clearly distinct species, and our results also indicate the existence of another previously unrecognized Antarctic species, C. bouvetensis sp.n., as well as an Antarctic lineage closely related to the endemic Kerguelen group C. robusta s.str. We find evidence for strong regional differentiation within each species. Our results suggest that diversity of Antarctic pycnogonids is still underestimated.
... Morphology Ethanol-preserved specimens were analyzed under a stereomicroscope (Olympus BX40) and a Zeiss DSM 950 scanning electron microscope (SEM). Since the ovigeral spine fields are of particular taxonomic importance (see, e.g., Fry and Hedgpeth 1969; Cano and López González 2007 ), we analyzed ovigeral spine fields in samples from five of the six Colossendeis megalonyx clades, in two C. tenera specimens, and one C. angusta specimen (Table 1). For the SEM pictures we first dried samples of the ovigera by adding hexamethyldisilazane (HMDS) in a rising concentration every 15 min. ...
Within the Pycnogonida, genetic studies have revealed that Colossendeis megalonyx Hoek (Challenger Report, Zoology, 3(X), 1–167, 1881), consists of a complex of several cryptic or overlooked species. Colossendeis megalonyx is a typical Southern Hemisphere species complex distributed primarily on the continental shelves in the Antarctic and Subantarctic. However, a different Colossendeis species with a completely different geographic distribution range, Colossendeis tenera Hilton (Journal of Entomology and Zoology, Pomona College, Claremont, 35(1), 2–4, 1943), was considered a subspecies of Colossendeis megalonyx by Turpaeva (Trudy Instituta Okeanology "P. P. Shirshova", Akademy Nauk SSSR, 103, 230–246, 1975). Colossendeis tenera occurs pre-dominantly along the Pacific Coast of North America from the Bering Sea to central California. Prominent differences between these two currently distinct species are found in body proportions and other characters that were interpreted by Turpaeva as a possible case of pedomorphosis induced by deep-sea conditions. In this study, we tested the hypothesis that Colossendeis tenera belongs to the Colossendeis megalonyx complex by analyzing available and novel sequence data (CO1 and H3) of both Colossendeis megalonyx and Colossendeis tenera as well as a similar, apparently closely related species, Colossendeis angusta Sars (Archiv for Mathematik og Naturvidenskab, 2, 237–271, 1877). We compared morphometric data and SEM of the ovigera of these species. Our results clearly indicate that Colossendeis tenera and Colossendeis angusta are not a part of the Colossendeis megalonyx complex. A sister-group relationship of Colossendeis tenera and Colossendeis angusta is strongly supported, but Colossendeis tenera is not clearly resolved as monophyletic with respect to Colossendeis angusta. This work highlights the need for further examination of the variation found in the tenera-angusta clade. It also gives a first hint of the phylogenetic affinities of species within Colossendeis.
... Thus, special attention will be paid to the species of this genus with the present collected material. On the other hand, recent studies carried out on Nymphon and Colossendeis show the presence of cryptic species, and the necessity to evaluate other morphological and molecular characters (Cano and López-González, 2007a;Arango et al., 2011). ...
... The material collected in this cruise will be of special interest in the study of the inter-and intraspecific variability of Colossendeis and Nymphon species. A previous paper (Cano and López-González, 2007a) evaluated the structure diversity on the last ovigerous segment in a group of Antarctic Colossendeis species by SEM. This paper provided an additional number of characters useful to discriminate between species and species groups. ...
The Southern Ocean ecosystem at the Antarctic
Peninsula has steep natural environmental gradients, e.g. in
terms of water masses and ice cover, and experiences
regional above global average climate change. An ecological
macroepibenthic survey was conducted in three
ecoregions in the north-western Weddell Sea, on the continental
shelf of the Antarctic Peninsula in the Bransfield
Strait and on the shelf of the South Shetland Islands in the
Drake Passage, defined by their environmental envelop.
The aim was to improve the so far poor knowledge of the
structure of this component of the Southern Ocean
ecosystem and its ecological driving forces. It can also
provide a baseline to assess the impact of ongoing climate
change to the benthic diversity, functioning and ecosystem
services. Different intermediate-scaled topographic features
such as canyon systems including the corresponding
topographically defined habitats ‘bank’, ‘upper slope’,
‘slope’ and ‘canyon/deep’ were sampled. In addition, the
physical and biological environmental factors such as seaice
cover, chlorophyll-a concentration, small-scale bottom
topography and water masses were analysed. Catches by
Agassiz trawl showed high among-station variability in
biomass of 96 higher systematic groups including ecological
key taxa. Large-scale patterns separating the three
ecoregions from each other could be correlated with the
two environmental factors, sea-ice and depth. Attribution
to habitats only poorly explained benthic composition, and
small-scale bottom topography did not explain such patterns
at all. The large-scale factors, sea-ice and depth,
might have caused large-scale differences in pelagic benthic coupling, whilst small-scale variability, also
affecting larger scales, seemed to be predominantly driven
by unknown physical drivers or biological interactions.
... Thus, special attention will be paid to the species of this genus with the present collected material. On the other hand, recent studies carried out on Nymphon and Colossendeis show the presence of cryptic species, and the necessity to evaluate other morphological and molecular characters (Cano and López-González, 2007a;Arango et al., 2011). ...
... The material collected in this cruise will be of special interest in the study of the inter-and intraspecific variability of Colossendeis and Nymphon species. A previous paper (Cano and López-González, 2007a) evaluated the structure diversity on the last ovigerous segment in a group of Antarctic Colossendeis species by SEM. This paper provided an additional number of characters useful to discriminate between species and species groups. ...
... Thus, special attention will be paid to the species of this genus with the present collected material. On the other hand, recent studies carried out on Nymphon and Colossendeis show the presence of cryptic species, and the necessity to evaluate other morphological and molecular characters (Cano and López-González, 2007a;Arango et al., 2011). ...
... The material collected in this cruise will be of special interest in the study of the inter-and intraspecific variability of Colossendeis and Nymphon species. A previous paper (Cano and López-González, 2007a) evaluated the structure diversity on the last ovigerous segment in a group of Antarctic Colossendeis species by SEM. This paper provided an additional number of characters useful to discriminate between species and species groups. ...
