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1.
Zookeys ; 1088: 129-171, 2022.
Article in English | MEDLINE | ID: mdl-35437367

ABSTRACT

Eight new species of Embioptera from Brazil are described, diagnosed, and illustrated. For Anisembiidae: Chelicercaachilata Szumik, Pereyra & Juárez, sp. nov.; Saussurembiaborba Szumik, Pereyra & Juárez, sp. nov. For Archembiidae: Archembiaoruma Szumik, sp. nov.; Embolynthaoriximina Szumik, Pereyra & Juárez, sp. nov.; Pararhagadochirbonita Szumik, Pereyra & Juárez, sp. nov., Pararhagadochirmarielleae Szumik, Pereyra & Juárez, sp. nov.; Pararhagadochirpara Szumik, Pereyra & Juárez, sp. nov. For Clothodidae: Chromatoclothodalanga Szumik, Pereyra & Juárez, sp. nov. To clarify the higher classification of the Order and to have an accurate taxonomy, a species catalog and introduction to the four families present in Brazil is also detailed, including phylogenetic relationships, taxonomic actions, composition, distributions, and records maps. Herein, several taxonomic acts are proposed: (1) the synonymy of Chelicerca Ross (= Dactylocerca Ross confirmed junior synonym; = Schizembia Ross syn nov.; = Pelorembia Ross, confirmed junior synonym; = Cryptembia Ross, syn. nov.) and Saussurembia Davis (= Stenembia Ross, syn. nov.). (2) new status and delimitation for family Archembiidae Ross, stat. rev.; subfamily Archembiinae Ross, stat. rev.; subfamily Pachylembiinaestat. rev.; subfamily Scelembiinaestat. rev., and their genera included. (3) Diradiusunicolor (Ross) (Teratembiidae) comb. nov., and (4) new locality records for previously cited species in the region.

2.
Cladistics ; 37(5): 596-629, 2021 10.
Article in English | MEDLINE | ID: mdl-34570932

ABSTRACT

Evidence for phylogenetic analysis comes in the form of observed similarities, and trees are selected to minimize the number of similarities that cannot be accounted for by homology (homoplasies). Thus, the classical argument for parsimony directly links homoplasy with explanatory power. When characters are hierarchically related, a first character may represent a primary structure such as tail absence/presence and a secondary (subordinate) character may describe tail colour; this makes tail colour inapplicable when tail is absent. It has been proposed that such character hierarchies should be evaluated on the same logical basis as standard characters, maximizing the number of similarities accounted for by secondary homology, i.e. common ancestry. Previous evaluations of the homology of a given ancestral reconstruction contain the unintuitive quantity "subcharacters" (number of regions of applicability). Rather than counting subcharacters, this paper proposes an equivalent but more intuitive formulation, based on counting the number of changes into each separate state. In this formulation, x-transformations, the homoplasy for the reconstruction is simply the number of changes into the state beyond the first, summed over all states. There is thus no direct connection between homoplasy and number of steps, only between homoplasy and extra steps. The link between the two formulations is that, for any region of applicability of any character, a subcharacter can be interpreted as the change into the state that is plesiomorphic in that region. Although some authors have claimed that the equivalence between maximizing explanatory power and minimizing independent originations of similar features (i.e. the standard justification of parsimony) does not hold for inapplicable characters, evaluating homoplasy with x-transformations clearly connects the two sides of that equation. Furthermore, as the evaluation with x-transformations provides a direct count and a straightforward interpretation of homoplasy, it extends naturally into implied weighting, and sheds light on problems with additive, step-matrix or continuous characters. It also allows deriving transformation costs for recoding hierarchies as step-matrix characters (where recoded states correspond to permissible combinations of states in primary and secondary characters), so that homology of the original observations is properly measured. Those transformation costs set the cost of gaining the primary structure to the maximum difference between "present" states plus cost of loss, and difference between "present" states to the sum of user-defined transformation costs between secondary features. With such recoding, invoking multiple independent derivations of the structure and similar features will cost as many extra "steps" as the instances of similarities (in both original characters) that are not being homologized. The step-matrix recoding also can take into account nested dependences. We present a simple convention for naming characters, which TNT can use to automatically convert the original data into a step-matrix form and set the proper transformation costs. Finally, the basic elements for handling inapplicable characters in the context of maximum-likelihood inference are outlined, and some quantitative comparisons between different approaches to inapplicables are provided.


Subject(s)
Clinical Coding , Models, Genetic , Phylogeny , Algorithms
3.
Cladistics ; 37(5): 559-570, 2021 10.
Article in English | MEDLINE | ID: mdl-34570939

ABSTRACT

We analyzed 769 242 occurrence records for 115 424 species of terrestrial arthropods, from three biodiversity repositories (Global Biodiversity Information Facility (GBIF), Natural History Museum, London, and "Sistema de Informação Distribuído para Coleções Biológicas" (SpeciesLink)), to test the use of global-scale data points for quantitative assessments of areas of endemism. The data include Insecta (105,941 species), Arachnida (7984 species), Myriapoda (1229) and terrestrial crustaceans (270 Branchiopoda). The species were assigned to 14 543 higher taxonomic groups because such groups often characterize larger areas of endemism. Putative areas of endemism were visualized as sets of cells displaying unique groups of species without the assumption of hierarchical relationships. Yet, the use of 10° grid cells recovered many large areas broadly corresponding to biogeographic Regions (Nearctic, Neotropical, Panamanian, Palaearctic, Afrotropical, Australian, Oceanian and Oriental) albeit with the limits poorly defined. An analysis of 5° grids resulted in 306 sets included in the different biogeographic Realms: Afrotropical, Australian, Madagascan, Nearctic, Neotropical, Oceanian, Oriental, Palaearctic, Saharo-Arabian and Sino-Japanese. The Panamanian Realm comprises 89 partly overlapping sets, crossing the Nearctic and Neotropical boundaries. A total of 7338 species of Insecta were endemic to some areas (Sino-Japanese, Afrotropical, Panamanian, Palaearctic, among others), followed by Arachnida (412 spp) and 105 species in other clades ranked as "classes". Six sets were supported only by genera, except for Panamanian sets that were supported by genera and families. Many of the species in the dataset are included in IUCN red lists, but probably most of those have distributions more restricted than global areas of endemism; only 102 appear as endemic to some area (Neartic, Madagascan, Panamanian, Afrotropical, among others). The results show that data from global databases can be used to identify areas of endemism on a worldwide basis but-owing to their incompleteness-only at a relatively coarse level. At the level of resolution currently allowed by such databases, such global studies are only complementary to studies where areas are determined subjectively by systematists (instead of actual point records), or studies using point records in datasets for specific taxonomic groups curated and compiled by specialists.


Subject(s)
Arthropods , Biodiversity , Animals , Arachnida , Arthropods/classification , Geography , Insecta/classification , London
4.
Neotrop. ichthyol ; 19(4): e200153, 2021. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1351154

ABSTRACT

Ecoregions and areas of endemism are central concepts in biogeography. Based on collection records and the Endemic Analyses implemented with NDM/VNDM method we analyzed fish areas of endemism in the junction of three freshwater ecoregions related to the Rio de la Plata estuary (Lower Parana, Lower Uruguay, Laguna dos Patos) in Southern Neotropical region. Using two grid cell sizes, results obtained showed the same general patterns. Areas of endemism recovered were mainly associated either to Lower Uruguay or to Laguna dos Patos. In both ecoregions nested areas of endemism were identified within larger patterns of endemism. Noteworthy, one area recovered occurred across Lower Uruguay and Laguna dos Patos limits. Our results also suggest a revision of the Lower Uruguay and Lower Parana ecoregion limits, and highlight the relevance of the Rio de la Plata estuary as a barrier and corridor for freshwater fishes in the area.(AU)


Las ecorregiones y áreas de endemismo son conceptos centrales en biogeografía. Basados en registros de colecciones y el análisis de endemismo implementado en NDM/VNDM, analizamos áreas de endemismo de peces en el sur de la región Neotropical, en la conjunción de tres ecorregiones de agua dulce relacionadas al estuario del Río de la Plata (Bajo Paraná, Bajo Uruguay, Laguna de los Patos). Usando dos tamaños de grilla, los resultados obtenidos mostraron los mismos patrones generales. Las áreas de endemismo obtenidas estuvieron principalmente asociadas tanto a la ecorregión Bajo Uruguay como a la Laguna de los Patos. En los dos casos, fueron identificadas áreas de endemismo anidadas dentro de los grandes patrones de endemismo. Además, se destacó un área que atravesó los límites de ambas ecorregiones. Nuestros resultados también sugieren que es necesaria una revisión de los límites entre Bajo Uruguay y Bajo Paraná y resaltan la relevancia del estuario del Río de la Plata como barrera y corredor para los peces de agua dulce de esta región.(AU)


Subject(s)
Animals , Dams , Fishes , Grid Cells , Fresh Water
5.
Cladistics ; 35(2): 198-229, 2019 Apr.
Article in English | MEDLINE | ID: mdl-34622975

ABSTRACT

The concept of "areas of endemism", and the assumption that these patterns are always a consequence of vicariant events, are reviewed. This assumption is related to the idea that areas of endemism have well-defined limits and never share any surface with other areas of endemism because they must represent sister areas supported by sister taxa. Based on this idea, overlapping areas have been considered rarely, or ignored completely. Using a data set of mammals of North America, we test here whether the overlapping areas are indeed sister areas supported by sister taxa, thus evaluating whether vicariant events are commonly the factor producing areas of endemism.

6.
Cladistics ; 32(1): 82-89, 2016 Feb.
Article in English | MEDLINE | ID: mdl-34732022

ABSTRACT

This paper examines a recent proposal to calculate supertrees by minimizing the sum of subtree prune-and-regraft distances to the input trees. The supertrees thus calculated may display groups present in a minority of the input trees but contradicted by the majority, or groups that are not supported by any input tree or combination of input trees. The proponents of the method themselves stated that these are serious problems of "matrix representation with parsimony", but they can in fact occur in their own method. The majority rule supertrees, being explicitly clade-based, cannot have these problems, and seem much more suited to retrieving common clades from a set of trees with different taxon sets. However, it is dubious that so-called majority rule supertrees can always be interpreted as displaying those clades present (or compatible with) with a majority of the trees. The majority rule consensus is always a median tree, in terms of the Robinson-Foulds distances (i.e. it minimizes the sum of Robinson-Foulds distances to the input trees). In contrast, majority rule supertrees may not be median-different, contradictory trees may minimize Robinson-Foulds distances, while their strict consensus does not. If being "majority" results from being median in Robinson-Foulds distances, this means that in the supertree setting a "majority" is ambiguously defined, sometimes achievable only by mutually contradictory trees.

7.
Mol Phylogenet Evol ; 88: 93-104, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25865266

ABSTRACT

This paper describes an efficient implementation of triplet-based measures of stability, in the program TNT. The only available implementations of such measures are much slower than the present one, either because of an inefficient implementation (Phyutility, Thor) or because the stability is evaluated with quartets (RogueNaRok, requiring O(t(4)), instead of the O(t(3)) possible for triplets). The method to quickly calculate triplets is applied to solving IterPCR (Pol and Escapa, 2009). It is shown that, in some cases, IterPCR or other algorithms in the program TNT (e.g. commands prunnelsen, prunmajor, or chkmoves) produce more informative results than analysis with RogueNaRok.


Subject(s)
Phylogeny , Software , Algorithms
8.
Cladistics ; 31(5): 568-572, 2015 Oct.
Article in English | MEDLINE | ID: mdl-34753267

ABSTRACT

Quantitative analyses of areas of endemism have rarely considered higher taxa. This paper discusses aspects related to the use of higher taxa in the analysis of areas of endemism, and computer implementations. An example of the application of the method is provided, with a data set for Nearctic mammals, showing that some of the areas recognized by species-level taxa also adjust well to the distribution of other taxa of higher level (genera, monophyletic groups).

9.
Cladistics ; 28(6): 645-654, 2012 Dec.
Article in English | MEDLINE | ID: mdl-34856733

ABSTRACT

There is as yet no general agreement regarding the most appropriate solution to the problem of identifying areas of endemism, not even in particular cases. In this study, we compared Endemicity Analysis (EA), Parsimony Analysis of Endemicity (PAE), and Biotic Elements Analysis (BE) based on their ability to identify hypothetical predefined patterns that represent nested, overlapping, and disjoint areas of endemism supported by species with different degrees of sympatry. We found that PAE performs poorly when applied to patterns that either overlap with each other or are supported by species with imperfect sympatry. BE exhibits a counterintuitive sensitivity to the degree of congruence among the distributions of endemic species, being unable to recognize areas of endemism supported by perfectly sympatric species. In contrast, in all cases examined we found that EA results in a high proportion of correctly identified distributional patterns. In addition to highlighting the strengths and limitations of these approaches, our results show how different methods can lead to seemingly conflicting conclusions and caution about the possibility of identifying distributional patterns that are merely methodological artefacts. © The Willi Hennig Society 2012.

10.
Cladistics ; 28(3): 317-329, 2012 Jun.
Article in English | MEDLINE | ID: mdl-34872190

ABSTRACT

The idea of an area of endemism implies that different groups of plants and animals should have largely coincident distributions. This paper analyses an area of 1152 000 km2 , between parallels 21 and 32°S and meridians 70 and 53°W to examine whether a large and taxonomically diverse data set actually displays areas supported by different groups. The data set includes the distribution of 805 species of plants (45 families), mammals (25 families), reptiles (six families), amphibians (five families), birds (18 families), and insects (30 families), and is analysed with the optimality criterion (based on the notion of endemism) implemented in the program NDM/VNDM. Almost 50% of the areas obtained are supported by three or more major groups; areas supported by fewer major groups generally contain species from different genera, families, or orders. © The Willi Hennig Society 2011.

11.
Cladistics ; 27(6): 617-628, 2011 Dec.
Article in English | MEDLINE | ID: mdl-34875812

ABSTRACT

Based on Hovenkamp's ideas on historical biogeography, we present a method for analysis of taxon history, spatial analysis of vicariance, which uses observed distributions as data, thus requiring neither predefined areas nor assumptions of hierarchical relations between areas. The method is based on identifying sister nodes with disjunct (allopatric/vicariant) distributions. To do this across the tree, internal nodes are assigned distributions (as the sum of the distributions of the descendant nodes). When distributions are less than ideal, ignoring the distribution of the problematic node(s) when assigning a distribution to their ancestors may allow us to consider additional sister nodes (i.e. those resulting from splits basal to the problematic node) as having disjunct distributions. The optimality criterion seeks to find the best (possibly weighted) compromise between the maximum possible number of disjunct sister nodes and the minimum number of eliminated distributions. The method can also take overlap into account. The methodology presented is implemented in VIP, a computer program available at http://www.zmuc.dk/public/phylogeny/vip. © The Willi Hennig Society 2011.

12.
Dongwuxue Yanjiu ; 31(6): 633-44, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21174354

ABSTRACT

Several studies have characterized the Yungas as a separate biogeographic unit, mainly based in floristic components. However, these characterizations were mainly qualitative and did not include faunal groups. The Yungas have been assumed as a region with rich floral and faunal diversity, but without testing how well they are described by animal distributions. Our study consists of a formal analysis of endemism based on distribution of small mammals in the southernmost portion of the Yungas. This area is biogeographically very interesting because the Yungas are comprised of discontinuous fragments of forests that extend into temperate arid and semiarid habitats. As a first approximation, we contrasted a group of volant species (bats) versus a group of non-volant species (marsupials). Our results show that small mammals are efficient indicators of endemism in Yungas. Eighty percent of the species of small marsupials included in the analysis supported the identified areas as being zones of endemism. Regarding bats, almost 55 percent of the species supported a designation of endemism. The results also show that the areas we considered are congruent with the botanical definition of the Yungas of northwestern Argentina and their subdivisions, an assumption that had not been previously tested with a formal quantitative method. We also found that non-volant species are better indicators of endemism than volant ones at regional scales, but volant species are better indicators than was previously thought.


Subject(s)
Chiroptera/physiology , Ecosystem , Marsupialia/physiology , Trees , Animals , Argentina
13.
Cladistics ; 26(2): 202-226, 2010 Apr.
Article in English | MEDLINE | ID: mdl-34875758

ABSTRACT

The 27th meeting of the Willi Hennig Society was held at the Sierras de San Javier, Tucumán (27-31 October 2008), jointly with the VIII Reunión Argentina de Cladística y Biogeografía. This was the second Hennig meeting held in South America and the third in Latin America. The event was attended by 129 participants from 16 countries, with the strongest presence from Argentina, USA and Brazil. As pointed out in the minutes of previous meetings, student participation is a good measure of the health of a society, and by this measure, the Hennig society is doing very well. For this meeting, 64 of the participants (50%) were students, 40 of which had authored or co-authored a talk or poster. The schedule was intense, with 98 presentations (67 talks and 31 posters). The sessions consisted of contributed papers, and five symposia on diverse topics: Large Scale Analyses of Large Chunks of Life, Molecular Systematics, Latin American Biogeography in the 21st Century, Methodology, and Botanical Phylogenetics (each of the symposia, except the "green" one, had two or three student speakers). As is usual at these meetings, the atmosphere was informal and relaxed, with much discussion and debate (although the biogeographic symposium took first place for the heat of its exchanges). The Student Award Committee (Lone Aagesen, Dan Janies and Gitte Petersen) selected Santiago Catalano for the Hennig Award ('The optimization of landmark data: a three-dimensional approach'), Prashant Sharma for the Brundin Award ('Phylogenetic analysis of Sandokanidae (Arachnida, Opiliones, Laniatores): Evaluating the independence of associated gene regions'), and Sebastian Barrionuevo for the Rosen Award ('Continuous characters in a phylogenetic analysis of the frog genus Telmatobius'). In addition to the logistics and funding provided by the Willi Hennig Society, the event was supported by the Consejo Nacional de Investigaciones Científicas y Técnicas, Fundación Miguel Lillo, Instituto Superior de Entomología 'Dr Abraham Willink', and the Agencia Nacional de Promoción Científica y Tecnológica. © The Willi Hennig Society 2009.

14.
Cladistics ; 25(3): 295-310, 2009 Jun.
Article in English | MEDLINE | ID: mdl-34879615

ABSTRACT

The distribution data of 340 grass species sampled in a region of 53.219 km2 in the northwestern corner of Argentina (between ∼21°S and ∼24°S) were analyzed to search for concordance in species distributions by using the program NDM/VNDM. Here, the traditional biogeographic hypothesis proposed for the region is evaluated for the first time by using a quantitative method and an optimal criterion specifically developed within the context of areas of endemism. Three different grid sizes (0.5° × 0.5°, 0.35° × 0.35 ° and 0.2° × 0.2°) were used to analyze three nested data sets: species found in the Andes of Argentina, Bolivia and/or Chile; Andean distributed species; and all grass species found in the study region. The main areas supported by the analyses correspond generally to the traditional biogeographic hypothesis proposed for the region. Local distribution patterns defined by species restricted to the study region were best supported under the small grid sizes, while the bigger grid sizes recovered areas defined by species with a broader distribution. The local distribution patterns emerged in all the analyses even when widespread species were added to the data set. © The Willi Hennig Society 2009.

15.
Cladistics ; 25(3): 211-230, 2009 Jun.
Article in English | MEDLINE | ID: mdl-34879616

ABSTRACT

Obtaining a well supported schema of phylogenetic relationships among the major groups of living organisms requires considering as much taxonomic diversity as possible, but the computational cost of calculating large phylogenies has so far been a major obstacle. We show here that the parsimony algorithms implemented in TNT can successfully process the largest phylogenetic data set ever analysed, consisting of molecular sequences and morphology for 73 060 eukaryotic taxa. The trees resulting from molecules alone display a high degree of congruence with the major taxonomic groups, with a small proportion of misplaced species; the combined data set retrieves these groups with even higher congruence. This shows that tree-calculation algorithms effectively retrieve phylogenetic history for very large data sets, and at the same time provides strong corroboration for the major eukaryotic lineages long recognized by taxonomists.

17.
Cladistics ; 24(6): 993-1005, 2008 Dec.
Article in English | MEDLINE | ID: mdl-34892879

ABSTRACT

A cladistic analysis of embiopterans, based on 157 species (representing 70% of the known genera) and 186 morphological characters, is presented, as well as a molecular analysis for 22 taxa using genes encoding 16S, 18S and 28S rDNA and COI. Species of all known families are included, except Andesembiidae Ross (specimens of which are in a private collection). The evidence presented supports the monophyly of four of the families (Australembiidae, Oligotomidae, Teratembiidae, and Anisembiidae). Notoligotomidae is paraphyletic and included within the Afro-neotropical family Archembiidae (which is also paraphyletic). The genera Embia, Cleomia, Macrembia, and Dihybocercus (Embiidae) form, together with Australembiidae, a group strongly supported by morphology; the position of the remaining genera of Embiidae has two quite different resolutions. Almost 80% of the genera of Anisembiidae recently described appear as either paraphyletic or polyphyletic. Contrary to the opinion of other specialists, the major groups as well as the monophyly of some families are supported by features which have been ignored in classical approaches to the systematics of Embioptera, such as the ovipositor and cephalic and leg structures, characters with an almost perfect fit.

18.
Syst Biol ; 53(6): 968-77, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15764564

ABSTRACT

The grid-based method to identify areas of endemism proposed by Szumik et al. is extended. The improvements include the ability to assign scores of endemicity to sets of disjoint areas, and to have each species contribute more to the score of endemicity of an area, or less, according to how well its distribution matches the area. The modified method also allows for partially overlapping areas; an area partially overlapping with another one of higher score is retained when the set of lower score has a minimum proportion of species endemic to it. Algorithms to evaluate areas of endemism under this criterion are discussed, and implemented in a computer program (NDM). The new algorithms allow evaluation of much larger data sets.


Subject(s)
Algorithms , Environment , Models, Theoretical , Animals , Environmental Monitoring , Geography , Population Dynamics
19.
Syst Biol ; 51(5): 806-16, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12396592

ABSTRACT

A formal method was developed to determine areas of endemism. The study region is divided into cells, and the number of species that can be considered as endemic is counted for a given set of cells (= area). Thus, the areas with the maximum number of species considered endemic are preferred. This is the first method for the identification of areas of endemism that implements an optimality criterion directly based on considering the aspects of species distribution that are relevant to endemism. The method is implemented in two computer programs, NDM and VNDM, available from the authors.


Subject(s)
Ecosystem , Models, Theoretical , Demography , Geography , Species Specificity
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