Refine
Document Type
- Article (4)
- Part of Periodical (1)
Language
- English (5)
Has Fulltext
- yes (5)
Is part of the Bibliography
- no (5)
Keywords
- integrative taxonomy (3)
- molecular markers (2)
- Arteminae (1)
- Baja California Sur (1)
- DNA barcodes (1)
- Hidalgo (1)
- Jalisco (1)
- Mexico (1)
- Michoacan (1)
- Neoricinulei (1)
Based on an integrative taxonomic approach, a new species of the genus Loxosceles Heineken & Lowe, 1832, is described from the state of Hidalgo, Mexico. Loxosceles tolantongo sp. nov. is described based on DNA barcoding using cytochrome c oxidase subunit 1 (CO1) and internal transcribed spacer 2 (ITS2), and morphology. For species delimitation, four molecular methods were implemented: 1) corrected p-distances under neighbor joining (NJ); 2) automatic barcode gap discovery (ABGD); 3) general mixed yule coalescent model (GMYC) and 4) Bayesian Poisson tree processes (bPTP). The new species morphologically resembles L. jaca, another species from Hidalgo, but there are morphological differences mainly in the tibiae of the male palp, the seminal receptacles of the females and also the high genetic p-distances. CO1 was more informative than ITS2 for the genetic separation; however, both concatenated genes (CO1 + ITS2) present robust evidence for species delimitation. Loxosceles tolantongo sp. nov. is considered a unique species for four reasons: 1) it can be diagnosed and distinguished by morphological characters (of the male palps mainly, but also of the seminal receptacles of the females); 2) the genetic p-distances with CO1 were high (>10%); 3) the molecular species delimitation methods were congruent under CO1 and CO1 + ITS2; and 4) under CO1 and CO1 + ITS2, the new species is a putative sister group of L. jaca + L. tenango.
The North American-Caribbean genera Pholcophora Banks, 1896 and Tolteca Huber, 2000 are representatives of Ninetinae, a group of small, cryptic, and thus poorly known pholcid spiders. We present the first comprehensive revisions of the two genera, including extensive SEM data and descriptions of seven new species from Mexico (Pholcophora mazatlan Huber sp. nov., P. papanoa Huber sp. nov., P. tehuacan Huber sp. nov., Tolteca huahua Huber sp. nov., T. manzanillo Huber sp. nov., T. oaxaca Huber sp. nov., and T. sinnombre Huber sp. nov.). We add new CO1 sequences of nine species to previously published molecular data and use these for a preliminary analysis of relationships. We recover a North American-Caribbean clade including ‘true’ (mainland) Pholcophora, Tolteca (Mexico), and a Caribbean clade consisting of the genus Papiamenta Huber, 2000 (Curaçao) and Caribbean ‘Pholcophora’. First karyotype data for Tolteca (2n♂ = 13, X1X2Y and 15, X1X2Y, respectively) reveal a strong reduction of the number of chromosome pairs within the North American-Caribbean clade, and considerable karyotype differentiation among congeners. This agrees with considerable CO1 divergence among species of Tolteca but contrasts with very inconspicuous morphological divergence. Environmental niche analyses show that the widespread P. americana Banks, 1896 (western USA, SW Canada) occupies a very different niche than its Mexican congeners and other close relatives. Caribbean taxa also have a low niche overlap with ‘true’ Pholcophora and Tolteca, supporting the idea that Caribbean ‘Pholcophora’ are taxonomically misplaced.
A new species of epigean ricinuleid of the genus Pseudocellus Platnick, 1980 from El Triunfo Biosphere Reserve, Chiapas, Mexico is described. DNA barcoding utilizing mitochondrial cytochrome c oxidase subunit 1 (CO1) and morphology were used for species delimitation. Molecular analyses and species delimitation included four methods: 1) General Mixed Yule Coalescent model (GMYC), 2) Automatic Barcode Gap Discovery (ABGD), 3) Bayesian Poisson Tree Process (bPTP), and 4) Assemble Species by Automatic Partitioning (ASAP). All molecular methods and morphology were consistent in delimiting and recognizing the new species described herein. The average interspecific genetic distance (p-distance) among analyzed species of Pseudocellus was 11.6%. The species is described based on adult males and females: Pseudocellus giribeti sp. nov. This is the seventh species described from Chiapas, which holds the highest number of ricinuleids species for the country. The total number of described species of Pseudocellus from Mexico increases to 21, having the highest species diversity of known ricinuleids worldwide.
Four new species of the spider genus Physocyclus Simon, 1893 are described from Mexico. Two species are described based on male and female adult specimens: Physocyclus mariachi sp. nov. and P. sikuapu sp. nov. Two species are described only with female adult specimens: P. lyncis sp. nov. and P. pocamadre sp. nov. The biogeographical province with the highest diversity of species is the Balsas Depression, located in the Mexican Neotropic, with 12 species. Physocyclus lyncis sp. nov. belongs to the dugesi species group, whereas the other three new species belong to the globosus species group. The total number of species of Physocyclus is increased to 37, distributed in North America (mainly Mexico) and Central America, with one cosmopolitan species: P. globosus. Updated taxonomic identification keys for males and females are provided.
A new species of the spider genus Latrodectus Walckenaer, 1805 from Mexico is described based on an integrative taxonomic approach. Latrodectus occidentalis Valdez-Mondragón sp. nov. is described using the molecular markers cytochrome c oxidase subunit 1 (CO1) and internal transcribed spacer 2 (ITS2), morphology of male and female specimens, and Species Distribution Models (SDM). Four molecular methods for species delimitation were implemented. The new species is characterized by having a unique dorsal coloration pattern on the abdomen. Latrodectus occidentalis sp. nov. is considered a distinct and valid species for four reasons: (1) it can be distinguished by morphological characters (genital and somatic); (2) the average interspecific genetic variation is > 2%; (3) 12 haplotypes were recovered within the species, being separated by the next close haplogroup of L. hesperus Chamberlin & Ivie, 1935 (30 mutations); and (4) congruence was observed among the four molecular methods. The number of recorded species of Latrodectus from Mexico increases to four: Latrodectus mactans (Fabricius, 1775), L. hesperus Chamberlin & Ivie, 1935, L. geometricus C.L. Koch, 1841 (introduced), and L. occidentalis sp. nov. The diversity of the genus Latrodectus from Mexico is surely underestimated, and more sampling is needed from the different biogeographical provinces and ecoregions to fill in these gaps.