RESUMEN
Gonyleptes robustus Holmberg, 1876 (Opiliones, Gonyleptidae), hitherto under the synonymy of Acanthopachylus aculeatus (Kirby, 1819) is revalidated. It is recognized as the second species of genus Acanthopachylus Roewer, 1913, currently monotypic, giving the new combination Acanthopachylus robustus (Holmberg, 1876) comb. nov. The huge synonymy formerly assigned to A. aculeatus is split among the newly identified entities. Diagnostic differences (male exomorphology) that underlie the taxonomic and nomenclatural decision are succinctly displayed. Brief historical references to the arachnological work of Eduardo L. Holmberg are also given.
Asunto(s)
Arácnidos , Distribución Animal , Animales , MasculinoRESUMEN
The long-neglected Chilean harvestman species Pachylus crassus (Roewer, 1943) (Gonyleptidae, Pachylinae) is redescribed and illustrated from the types and additional material. A lectotype is designated from the original syntype series. Until now P. crassus was only known from its brief original description. Moreover, its generic affiliation remained obscure for decades, as it was successively placed in different genera until it was determined to be a member of Pachylus C.L. Koch, 1839. Aside some taxonomic remarks on the genus, it is here proposed to exclude from Pachylus one doubtful nominal species, Pachylus acanthops (Gervais, 1849), and to consider it a species inquirenda. A thorough comparison of P. crassus with its presumed close relative, P. quinamavidensis Muñoz, 1969, is provided. New records for both species and a map with all known localities of the genus are also given.
Asunto(s)
Arácnidos/clasificación , Distribución Animal , Animales , ChileRESUMEN
The harvestmen family Gonyleptidae (Opiliones), the largest one in the Neotropics (Kury 2003), is astonishingly diverse in eastern South America. The species-rich genus Eusarcus Perty, 1833, is characteristic for this area. It is the second largest gonyleptid genus (Kury 2003; Hara Pinto-da-Rocha 2010), with a long taxonomical history beginning in the 19th century, when Perty (1833) described the genus together with four species. The number of species increased gradually in the 20th century through the addition of new descriptions and the synonymies of several related genera, with the corresponding species transferals (Hara Pinto-da-Rocha 2010). Eusarcus is a relatively well-studied taxon that has undergone a thorough systematic revision (Hara Pinto-da-Rocha 2010). Currently the genus contains 40 valid species, some of them cave-dwellers, with 32 species inhabiting the Atlantic rainforest and Paraná semi-deciduous forests (Saraiva DaSilva 2016; Santos Júnior et al. 2021). The remaining species are peripheral to the core geographic area and are found in the Brazilian Cerrado, in Paraguay, or in the "Pampas" grasslands of Argentina, Uruguay, and southern Brazil (Hara Pinto-da-Rocha 2010).
Asunto(s)
Arácnidos/clasificación , Animales , Argentina , Brasil , UruguayRESUMEN
In its first twenty years of existence Zootaxa has been widely utilized among researchers of Opiliones, mainly those coming from Latin American countries, principally Brazil. During 20032020, a total of 141 papers on Opiliones were published in Zootaxa (no papers were published on Opiliones in the first two years, 20012002). The journal has greatly facilitated the dissemination of knowledge on Opiliones, especially with respect to the taxonomy and systematics of harvestmen from the Neotropical Realm. Those 141 papers in Zootaxa include almost a quarter (191) of the new species of Opiliones described between 2001 and 2020, as well as 112 new synonymies. Additionally, 27 of those papers proposed 182 new or restored combinations. A total of 108 authors working in 25 countries have contributed papers to Zootaxa focusing on Opiliones. There is clearly a predominance for collaborative contributions with more than twice as many papers authored by two or more authors compared to single-author publications. In general, the majority of papers deal within the local biogeographic realm (where the lead author resides). Studies of harvestmen from seven of the eight biogeographic realms were published in Zootaxa during 20032020. The largest portion of these contributions were by far focused on the Neotropical opiliofauna, but Australasian, Nearctic, Indomalayan, Palearctic, Afrotropical and Antarctic opiliofauna are covered as well. No papers on Opiliones have been published in Zootaxa by authors representing countries in Africa. We also recognize a strong gender bias in authorship and the current composition of Opiliones subject editors. We will strive to create an inclusive environment and aim to promote diversity of scientists who study Opiliones.
Asunto(s)
Arácnidos/clasificación , Animales , Femenino , Masculino , Publicaciones Periódicas como Asunto , SexismoRESUMEN
The nomenclatural history of the collared and white-lipped peccaries, two well-recognized taxonomic entities, has been confusing. From the 18th century to the beginning of the 20th century, several genera were created, most of them without an explicit designation of type species. Due to differing opinions as to whether the two species should be included in a single genus or, if separate genera were recognized, which generic name should be applied to each of the two taxa, the validity of generic and specific names oscillated until even recently. This paper aims to solve these nomenclatural issues by reviewing the different taxonomic arrangements of these two peccaries and applying appropriately the International Code on Zoological Nomenclature. We contend that the valid generic name for the white-lipped peccary is Tayassu Fischer, 1814 (type Sus pecari Link, 1795), while Dicotyles Cuvier, 1816 (type Dicotyles torquatus Cuvier, 1816) is the valid genus for the collared peccary, with Pecari Reichenbach, 1835 as its junior synonym.
Asunto(s)
Artiodáctilos , AnimalesRESUMEN
A new genus of Gonyleptidae Pachylinae, Qorimayus gen. nov., is described to place the high-altitude species originally named Parabalta alticola Ringuelet, endemic to Sierra de Famatina, western Argentina. While classical exomorphological features do not separate this new genus from Parabalta Roewer or Pachyloides Holmberg (to which the species was formerly combined), male genitalic features, especially the shape of the ventral process of stylus, differ clearly. In turn, penis morphology suggests the systematic relationship of Qorimayus gen. nov. with the Chilean genera Metabalta Roewer and Nanophareus Roewer. A cladistic analysis was performed to test the phylogenetic affinities of the new genus; 28 terminals were used, comprising selected species of Parabalta, Pachyloides, Metabalta and Nanophareus, as well as other Gonyleptidae to represent the 'subtropical' and the 'Chilean' opiliofaunistic elements; the most external outgroups included one cosmetid, one metasarcid and one nomoclastid. Results supported the recognition of Qorimayus as an independent genus, and its close relationship with the Chilean genera Metabalta and Nanophareus. A detailed redescription of Qorimayus alticola comb. nov., along with some habitat notes are given. The presumed zoogeographical links of this endemic species with the central Chilean opiliofauna are briefly discussed.
Asunto(s)
Arácnidos , Altitud , Distribución Animal , Animales , Argentina , Masculino , FilogeniaRESUMEN
The troglomorphic harvestman Otilioleptes marcelae gen. nov., sp. nov. from the basaltic cave Doña Otilia, Payunia region, Mendoza Province, Argentina, is described. Its systematic affinities were studied through cladistic and Bayesian analyses that included representatives of Gonyleptoidea; it was determined to represent a new monotypic family, Otilioleptidae fam. nov., occupying a basal position within the clade Laminata. This species shows accentuated troglomorphic traits, typical for troglobitic harvestmen: elongated appendages, depigmentation, reduction of eyes and fading of scutal sulci. Additionally, it almost lacks sexual dimorphism, the distal portion of coxa IV is not completely fused to the stigmatic segment, and penis morphology is remarkably divergent with other Laminata; these features cannot be attributed to cave adaptation and may reflect early lineage divergence. Otilioleptes marcelae is the first troglobitic gonyleptoid known from a lava tube. The xeric environments around the cave (Patagonian ecoregion) and the paleoenvironmental history of the area suggest the relictual character of O. marcelae. Scattered evidence supports a long time evolutionary scenario and a presumable relationship with the Chilean opiliofauna (especially with genus Osornogyndes). A comparative overview of all known troglobitic gonyleptoids is provided. The urgent need to protect this new species and its unique cave environment is emphasized.
Asunto(s)
Arácnidos/anatomía & histología , Arácnidos/fisiología , Teorema de Bayes , Evolución Biológica , Ecosistema , Animales , Arácnidos/clasificación , Argentina , Cuevas , Filogenia , Árboles , Erupciones VolcánicasRESUMEN
The disjunct distribution of the harvestman Discocyrtus dilatatus (Opiliones, Gonyleptidae) is used as a case study to test the hypothesis of a trans-Chaco Pleistocene paleobridge during range expansion stages. This would have temporarily connected humid regions ('Mesopotamia' in northeastern Argentina, and the 'Yungas' in the northwest, NWA) in the subtropical and temperate South American lowlands. The present study combines two independent approaches: paleodistributional reconstruction, using the Species Distribution Modeling method MaxEnt and projection onto Quaternary paleoclimates (6 kya, 21 kya, 130 kya), and phylogeographic analyses based on the cytochrome oxidase subunit I molecular marker. Models predict a maximal shrinkage during the warm Last Interglacial (130 kya), and the rise of the hypothesized paleobridge in the Last Glacial Maximum (21 kya), revealing that cold-dry stages (not warm-humid ones, as supposed) enabled the range expansion of this species. The disjunction was formed in the mid-Holocene (6 kya) and is intensified under current conditions. The median-joining network shows that NWA haplotypes are peripherally related to different Mesopotamian lineages; haplotypes from Santa Fe and Córdoba Provinces consistently occupy central positions in the network. According to the dated phylogeny, Mesopotamia-NWA expansion events would have occurred in the last glacial period, in many cases closely associated to the Last Glacial Maximum, with most divergence events occurring shortly thereafter. Only two (out of nine) NWA haplotypes are shared with Mesopotamian localities. A single, presumably relictual NWA haplotype was found to have diverged much earlier, suggesting an ancient expansion event not recoverable by the paleodistributional models. Different measures of sequence statistics, genetic diversity, population structure and history of demographic changes are provided. This research offers the first available evidence for the historical origin of NWA disjunct populations of a Mesopotamian harvestman.
Asunto(s)
Arácnidos/crecimiento & desarrollo , Cambio Climático , Animales , Arácnidos/clasificación , Arácnidos/genética , Modelos Teóricos , Paleontología , FilogeniaRESUMEN
The geographic range of the Neotropical harvestman Discocyrtus testudineus (Holmberg, 1876) (Gonyleptidae) is addressed by determining the species' bioclimatic profile and modeling its potential distribution. Analysis was performed on a record set of 71 localities, including literature records and 34 new localities reported here. The bioclimatic profile was characterized through extreme, median and dispersion features of the values of 19 bioclimatic variables across the record set. Predictive models were built with the presence-only methods MAXENT and, secondarily, BIOCLIM. Discocyrtus testudineus is a typical Mesopotamian harvestman, spreading across a wide region along the middle and lower Paraná River in subtropical / temperate Argentina, and extending, more or less continuously, up to the central province of Córdoba. Apparently diverging records (Paso de los Libres, on the Uruguay River, and Quilmes, on the southern coast of Rio de la Plata) proved to be predictable, even if suppressed from the dataset. Comparisons of cumulative frequencies curves and dispersion features (box-plots) were made with Discocyrtus dilatatus Sørensen, 1884 and Gryne orensis (Sørensen, 1884), other Mesopotamian species for which bioclimatic data are available. The relative importance of the bioclimatic variables used for modeling was also estimated.
Asunto(s)
Arácnidos/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Arácnidos/anatomía & histología , Arácnidos/crecimiento & desarrollo , Argentina , Tamaño Corporal , Clima , Ecosistema , Femenino , Masculino , Tamaño de los ÓrganosRESUMEN
The presence of Gryne orensis (Sørensen) (Opiliones: Cosmetidae) in a Yungas locality (northwestern Argentina) is reported for the first time, providing new evidence for the Mesopotamian-Yungas disjunct pattern. Combining a total of 19 new Mesopotamian records with previous, reliable citations from the literature, a dataset of 45 points was used to model the potential distribution of the species, using the presence-only methods BIOCLIM and MAXENT. Models supported the existence of a distributional gap across the Semiarid Chaco. The imprecise literature record from "El Impenetrable", province of Chaco, is assigned to three tentative locations to evaluate if models are affected by their inclusion; in all cases, the disjunction was maintained. It was thereby estimated that the actual record might have originated in a site closer to the Humid Chaco and/or associated to streams. This paper also provides a statement of the bioclimatic profile and identification of major environmental constraints that define the range of G. orensis.
Asunto(s)
Distribución Animal , Arácnidos/fisiología , Animales , Arácnidos/clasificación , Argentina , Clima , Modelos BiológicosRESUMEN
New records of the spider Chibchea salta Huber 2000 (Araneae, Pholcidae) from northwestern Argentina are provided, and the potential range of this species is modeled. Two presence-only methods, Maxent and Bioclim, were run using 19 bioclimatic parameters at a resolution of 30 arc seconds. The climatic profile of C. salta is described, and the relative importance of the bioclimatic variables is explored. Temperature variables proved to be more decisive to the final range shape. The range predicted with Maxent is slightly larger than with Bioclim, but the latter appears to be more sensitive to the record set bias. Both methods performed well, resulting in predictive ranges consistent with the yungas ecoregion. These results provide an initial insight into the bioclimatic tolerance of C. salta, and by identifying potential areas with no records, such as the sierras on the Salta-Jujuy border, they also help in identifying sites for future sampling efforts.