Karyotypic diversity and cryptic speciation: Have we vastly underestimated moss species diversity?

Karyotypic diversity is critical to catalyzing change in the evolution of all plants. By resulting in meiotic incompatibility among sets of homologous chromosomes, polyploidy and aneuploidy may facilitate reproductive isolation and the potential for speciation. Across plants, karyotypic variants in the form of allopolyploids receive greater taxonomic attention relative to autopolyploids and aneuploids. In particular, the prevalence and significance of autopolyploidy and aneuploidy in bryophytes is little understood. Using Fritsch’s 1991 compendium of bryophyte karyotypes with augmentation from karyological studies published since, we have quantified the prevalence of karyotypic variants among ~1500 extant morphological species of mosses. We assessed the phylogenetic distribution of karyological data, the frequency of autopolyploidy and aneuploidy, and the methodological correlates with karyotypic diversity. At least two ploidy levels were recorded from 17% of species potentially increasing current taxonomic diversity of mosses to over 15,000 species. We find that for a given species, the number of unique karyotypes recorded is correlated with the number of populations sampled. The evidence suggests that cytological diversity likely underlies yet undescribed species diversity in mosses, and that intensive karyological sampling is a needed tool for its discovery.

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Unveiling species diversity in collared frogs through morphological and bioacoustic evidence: a new Mannophryne (Amphibia, Aromobatidae) from Sierra de Aroa, northwestern Venezuela, and an amended definition and call description of M. herminae (Boettger, 1893)

Zootaxa ◽

10.11646/zootaxa.4461.4.1 ◽

2018 ◽

Vol 4461 (4) ◽

pp. 451 ◽

Cited By ~ 2

Author(s):

FERNANDO J.M. ROJAS-RUNJAIC ◽

MIGUEL E. MATTA-PEREIRA ◽

ENRIQUE LA MARCA

Keyword(s):

New Species ◽

Species Diversity ◽

Small Body ◽

Color Pattern ◽

Advertisement Call ◽

Undescribed Species ◽

Unique Combination ◽

Definition Of ◽

A New Species ◽

Lines Of Evidence

Species diversity in collared frogs of the genus Mannophryne is presumed to be underestimated due to the paucity of external morphology characters, but combining morphology with bioacoustics and other lines of evidence has shown to be useful in delimiting species of this group. Herein we describe a new species of Mannophryne from Sierra de Aroa in northwestern Venezuela. The new species is morphologically similar to M. herminae but is readily recognized by its strikingly different advertisement call. It also can be distinguished from all its congeners by the unique combination of its small body size, general color pattern, basal toe webbing, and advertisement call consisting of long trills of single tonal notes emitted at a rate of 2–3 notes/s. Additionally, to facilitate future diagnosis of undescribed species related to M. herminae, we amend the definition of the latter, describe in detail its advertisement call, and redefine its known distribution range. The new species increases the number of described species of Mannophryne to 20.

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Functional Diversity: An Epistemic Roadmap

BioScience ◽

10.1093/biosci/biz089 ◽

2019 ◽

Vol 69 (10) ◽

pp. 800-811 ◽

Cited By ~ 3

Author(s):

Christophe Malaterre ◽

Antoine C Dussault ◽

Sophia Rousseau-Mermans ◽

Gillian Barker ◽

Beatrix E Beisner ◽

...

Keyword(s):

Species Diversity ◽

Functional Diversity ◽

Functional Traits ◽

Management Strategies ◽

Taxonomic Diversity ◽

Ecological Management ◽

Diversity Studies

Abstract Functional diversity holds the promise of understanding ecosystems in ways unattainable by taxonomic diversity studies. Underlying this promise is the intuition that investigating the diversity of what organisms actually do (i.e., their functional traits) within ecosystems will generate more reliable insights into the ways these ecosystems behave, compared to considering only species diversity. But this promise also rests on several conceptual and methodological (i.e., epistemic) assumptions that cut across various theories and domains of ecology. These assumptions should be clearly addressed, notably for the sake of an effective comparison and integration across domains, and for assessing whether or not to use functional diversity approaches for developing ecological management strategies. The objective of this contribution is to identify and critically analyze the most salient of these assumptions. To this aim, we provide an epistemic roadmap that pinpoints these assumptions along a set of historical, conceptual, empirical, theoretical, and normative dimensions.

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Coleoptera of Canada

ZooKeys ◽

10.3897/zookeys.819.24724 ◽

2019 ◽

Vol 819 ◽

pp. 361-376 ◽

Cited By ~ 3

Author(s):

Adam J. Brunke ◽

Patrice Bouchard ◽

Hume B. Douglas ◽

Mikko Pentinsaari

Keyword(s):

Species Diversity ◽

Financial Support ◽

New Records ◽

Beetle Species ◽

Undescribed Species ◽

Index Numbers ◽

Number Of Species ◽

Candidate Species ◽

Substantial Progress

The beetle fauna of Canada was assessed, including estimates of yet unreported diversity using information from taxonomists and COI sequence clusters in a BOLD (Barcode of Life Datasystems) COI dataset comprising over 77,000 Canadian records. To date, 8302 species of Coleoptera have been recorded in Canada, a 23% increase from the first assessment in 1979. A total of 639 non-native beetle species have become established in Canada, with most species in the Staphylinidae (153 spp.), Curculionidae (107 spp.), Chrysomelidae (56 spp.) and Carabidae (55 spp.). Based on estimates from the taxonomic community and our BOLD dataset, we estimate that slightly more than 1000 beetle species remain to be reported from Canada, either as new records or undescribed species. Renewed enthusiasm toward and financial support for surveys, especially in the central and western provinces of Canada will be critical for detecting, documenting and describing these species. The Barcode of Life database is still far from comprehensive for Canadian Coleoptera but substantial progress has been made and the number of Barcode Index Numbers (BINs) (as candidate species) has reached nearly 70% of the number of species reported from Canada. Comparison of BINs to observed species in a group of Canadian Staphylinidae suggests that BINs may provide a good estimate of species diversity within the beetles. Histeridae is a diverse family in Canada that is notably underrepresented in BOLD. Families such as Mordellidae, Scraptiidae, Latridiidae, Ptiliidae and Scirtidae are poorly known taxonomically in Canada and are represented in our BOLD dataset by many more BINs than recorded species.

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Widespread polyploid forms off Lumbricillus lineatus (Müller) (Enchytraeidae: Oligochaeta): comments on polyploidism in the enchytraeids

Canadian Journal of Zoology ◽

10.1139/z95-204 ◽

1995 ◽

Vol 73 (9) ◽

pp. 1727-1734 ◽

Cited By ~ 8

Author(s):

Kathryn A. Coates

Keyword(s):

Geographical Distribution ◽

Taxonomic Diversity ◽

Conclusive Evidence ◽

Global Distribution ◽

Ploidy Levels ◽

The Family ◽

Ecological Breadth ◽

New Habitats

Studies of a small fresh collection of the marine intertidal enchytraeid oligochaete Lumbricillus lineatus (Müller) and taxonomic collections from 27 additional locations in Europe, Canada, and Australia reveal the presence of morphotypes corresponding to parthenogenetic autopolyploid forms, triploid, tetraploid, and pentaploid, of the species in all the regions represented by the collections. The extension of the range of these cytotypes from Europe to a virtually global distribution raises questions about the significance of parthenogenesis and polyploidism to their invasion of new habitats. Differences in reproduction rates and the ecological breadth of the different ploidy levels are not known. The geographical distribution and abundance of polyploids of L. lineatus, in themselves, do not provide conclusive evidence for the repeated origins of polyploids within the species, but strongly suggest that possibility. General theories link evolutionary polyploidy among animals with parthenogenesis, as seen in the polyploid forms of L. lineatus. However, polyploidism combined with out-crossing underlies the present taxonomic diversity of the family Enchytraeidae.

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Taxonomic diversity estimation using rarefaction

Paleobiology ◽

10.1017/s0094837300002633 ◽

1975 ◽

Vol 1 (4) ◽

pp. 333-342 ◽

Cited By ~ 197

Author(s):

David M. Raup

Keyword(s):

Species Richness ◽

Species Diversity ◽

Sample Size ◽

Fossil Record ◽

World Wide ◽

Taxonomic Diversity ◽

Early Jurassic ◽

Late Triassic ◽

Geologic Time ◽

Large Samples

Benthic ecologists have successfully applied rarefaction techniques to the problem of compensating for the effect of sample size on apparent species diversity (= species richness). The same method can be used in studies of diversity at higher taxonomic levels (families and orders) in the fossil record where samples represent world-wide distributions of species or genera over long periods of geologic time.Application of rarefaction to several large samples of post-Paleozoic echinoids (totaling 7,911 species) confirms the utility of the method. Rarefaction shows that the observed increase in the number of echinoid families since the Paleozoic is real in the sense that it cannot be explained solely by the increase in numbers of preserved species. There has been no statistically significant increase in the number of families since mid-Cretaceous, however. At the order level, echinoid diversity may have been nearly constant since late Triassic or early Jurassic.

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Low recombination rates in sexual species and sex–asex transitions

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2016.0461 ◽

2017 ◽

Vol 372 (1736) ◽

pp. 20160461 ◽

Cited By ~ 6

Author(s):

Christoph R. Haag ◽

Loukas Theodosiou ◽

Roula Zahab ◽

Thomas Lenormand

Keyword(s):

Model Systems ◽

Rate Variation ◽

Linkage Maps ◽

Undescribed Species ◽

Linkage Groups ◽

Recombination Rates ◽

Homologous Chromosomes ◽

Genetic Linkage Maps ◽

Chromosome Maps ◽

Recombination Rate Variation

In most sexual, diploid eukaryotes, at least one crossover occurs between each pair of homologous chromosomes during meiosis, presumably in order to ensure proper segregation. Well-known exceptions to this rule are species in which one sex does not recombine and specific chromosomes lacking crossover. We review other possible exceptions, including species with chromosome maps of less than 50 cM in one or both sexes. We discuss the idea that low recombination rates may favour sex–asex transitions, or, alternatively may be a consequence of it. We then show that a yet undescribed species of brine shrimp Artemia from Kazakhstan ( A . sp. Kazakhstan), the closest known relative of the asexual Artemia parthenogenetica , has one of the shortest genetic linkage maps known. Based on a family of 42 individuals and 589 RAD markers, we find that many linkage groups are considerably shorter than 50 cM, suggesting either no obligate crossover or crossovers concentrated at terminal positions with little effect on recombination. We contrast these findings with the published map of the more distantly related sexual congener, A. franciscana , and conclude that the study of recombination in non-model systems is important to understand the evolutionary causes and consequences of recombination. This article is part of the themed issue ‘Evolutionary causes and consequences of recombination rate variation in sexual organisms’.

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Endopolyploidy in Bryophytes: Widespread in Mosses and Absent in Liverworts

Journal of Botany ◽

10.1155/2010/316356 ◽

2010 ◽

Vol 2010 ◽

pp. 1-7 ◽

Cited By ~ 12

Author(s):

Jillian D. Bainard ◽

Steven G. Newmaster

Keyword(s):

Flow Cytometry ◽

Dna Replication ◽

Propidium Iodide ◽

Nuclear Division ◽

Common Phenomenon ◽

Ploidy Levels ◽

Moss Species ◽

Mean Cycle

Endopolyploidy occurs when DNA replication is not followed by mitotic nuclear division, resulting in tissues or organisms with nuclei of varying ploidy levels. Endopolyploidy appears to be a common phenomenon in plants, though the prevalence of endopolyploidy has not been determined in bryophytes (including mosses and liverworts). Forty moss species and six liverwort species were analyzed for the degree of endopolyploidy using flow cytometry. Nuclei were extracted in LB01 buffer and stained with propidium iodide. Of the forty moss species, all exhibited endopolyploid nuclei (mean cycle value =0.65±0.038) except for the Sphagnum mosses (mean cycle value =0). None of the liverwort species had endopolyploid nuclei (mean cycle value = 0.04 ± 0.014). As bryophytes form a paraphyletic grade leading to the tracheophytes, understanding the prevalence and role of endopolyploidy in this group is important.

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From marine park to future genomic observatory? Enhancing marine biodiversity assessments using a biocode approach

Biodiversity Data Journal ◽

10.3897/bdj.7.e46833 ◽

2019 ◽

Vol 7 ◽

Cited By ~ 6

Author(s):

Yin Cheong Aden Ip ◽

Ywee Chieh Tay ◽

Su Xuan Gan ◽

Hui Ping Ang ◽

Karenne Tun ◽

...

Keyword(s):

Species Diversity ◽

Animal Species ◽

Marine Biodiversity ◽

Dna Barcodes ◽

Undescribed Species ◽

Marine Fauna ◽

Species Numbers ◽

Marine Park ◽

First Results ◽

Genomic Observatory

Few tropical marine sites have been thoroughly characterised for their animal species, even though they constitute the largest proportion of multicellular diversity. A number of focused biodiversity sampling programmes have amassed immense collections to address this shortfall, but obstacles remain due to the lack of identification tools and large proportion of undescribed species globally. These problems can be partially addressed with DNA barcodes (“biocodes”), which have the potential to facilitate the estimation of species diversity and identify animals to named species via barcode databases. Here, we present the first results of what is intended to be a sustained, systematic study of the marine fauna of Singapore’s first marine park, reporting more than 365 animal species, determined based on DNA barcodes and/or morphology represented by 931 specimens (367 zooplankton, 564 macrofauna including 36 fish). Due to the lack of morphological and molecular identification tools, only a small proportion could be identified to species solely based on either morphology (24.5%) or barcodes (24.6%). Estimation of species numbers for some taxa was difficult because of the lack of sufficiently clear barcoding gaps. The specimens were imaged and added to “Biodiversity of Singapore” (http://singapore.biodiversity.online), which now contains images for > 13,000 species occurring in the country.

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Chromosome counts of eight Iranian endemic species of Nepeta L. (Lamiaceae)

Caryologia ◽

10.36253/caryologia-729 ◽

2021 ◽

Vol 74 (1) ◽

pp. 53-61

Author(s):

Maryam Hasaninejad ◽

Ziba Jamzad ◽

Saeid Afsharzadeh ◽

HojJatollah Saeidi

Keyword(s):

Chromosome Number ◽

Species Group ◽

Chromosome Length ◽

Basic Chromosome Number ◽

Chromosome Counts ◽

Ploidy Levels ◽

Study Results ◽

Karyotypic Diversity ◽

Karyotype Formula ◽

First Time

In this survey, the chromosome counts of eight Nepeta L. species were investigated and the karyotypic diversity among these species was studied. The examined species belong to N. cephalotes Boiss. species group, namely N. eremokosmos Rech.f., N. gloeocephala Rech. f., cephalotes Boiss., N. pungens (Bunge) Benth., N. ispahanica Boiss., N. mahanensis Jamzad & Simonds, N. hormozganica Jamzad and N. denudata Benth. collected from different habitats in Iran. The ploidy levels, karyotype formula, chromosome length range, total karyotype length, several karyotype asymmetries values and Stebbins classification were determined in this study. Results showed the same chromosome number, 2n = 2x= 18 for all studied species. The basic chromosome number for the above mentioned species are x = 9. Also, the smallest chromosome length is 1.02 μm in N. mahanensis. The largest chromosome length is 2.3 μm in N. ispahanica. The chromosomes of species were metacentric or submetacentric. According to the Stebbins classification, these species were located into three classes 1A, 2A and 3A. The chromosome numbers for six of studied species are reported here for the first time.

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