Species Recognition and Cryptic Species in the Tuber indicum Complex

Sexual traits that promote species recognition are important drivers of reproductive isolation, especially among closely related species. Identifying neural processes that shape species differences in recognition is crucial for understanding the causal mechanisms of reproductive isolation. Temporal patterns are salient features of sexual signals widely used in species recognition by several taxa, including anurans. Recent advances in our understanding of temporal processing by the anuran auditory system provide an opportunity to investigate the neural basis of species-specific recognition. The anuran inferior colliculus (IC) consists of neurons that are selective for temporal features of calls. Of potential relevance are auditory neurons known as interval-counting neurons (ICNs) that are often selective for the pulse rate of conspecific advertisement calls. Here, we tested the hypothesis that ICNs mediate acoustic species recognition by exploiting the known differences in temporal selectivity in two cryptic species of gray treefrog (Hyla chrysoscelis and Hyla versicolor). We examined the extent to which the threshold number of pulses required to elicit behavioral responses from females and neural responses from ICNs was similar within each species but potentially different between the two species. In support of our hypothesis, we found that a species difference in behavioral pulse number thresholds closely matched the species difference in neural pulse number thresholds. However, this relationship held only for ICNs that exhibited band-pass tuning for conspecific pulse rates. Together, these findings suggest that differences in temporal processing of a subset of ICNs provide a mechanistic explanation for reproductive isolation between two cryptic treefrog species.

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Delimiting cryptic species within the brown-banded bamboo shark, Chiloscyllium punctatum in the Indo-Australian region with mitochondrial DNA and genome-wide SNP approaches

BMC Ecology and Evolution ◽

10.1186/s12862-021-01852-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Fahmi ◽

Ian R. Tibbetts ◽

Michael B. Bennett ◽

Christine L. Dudgeon

Keyword(s):

Mitochondrial Dna ◽

New Species ◽

Cryptic Species ◽

Species Complex ◽

Species Recognition ◽

Full Range ◽

Research Management ◽

Operational Taxonomic Units ◽

Australian Region ◽

Genome Wide

Abstract Background Delimiting cryptic species in elasmobranchs is a major challenge in modern taxonomy due the lack of available phenotypic features. Employing stand-alone genetics in splitting a cryptic species may prove problematic for further studies and for implementing conservation management. In this study, we examined mitochondrial DNA and genome-wide nuclear single nucleotide polymorphisms (SNPs) in the brown-banded bambooshark, Chiloscyllium punctatum to evaluate potential cryptic species and the species-population boundary in the group. Results Both mtDNA and SNP analyses showed potential delimitation within C. punctatum from the Indo-Australian region and consisted of four operational taxonomic units (OTUs), i.e. those from Indo-Malay region, the west coast of Sumatra, Lesser Sunda region, and the Australian region. Each OTU can be interpreted differently depending on available supporting information, either based on biological, ecological or geographical data. We found that SNP data provided more robust results than mtDNA data in determining the boundary between population and cryptic species. Conclusion To split a cryptic species complex and erect new species based purely on the results of genetic analyses is not recommended. The designation of new species needs supportive diagnostic morphological characters that allow for species recognition, as an inability to recognise individuals in the field creates difficulties for future research, management for conservation and fisheries purposes. Moreover, we recommend that future studies use a comprehensive sampling regime that encompasses the full range of a species complex. This approach would increase the likelihood of identification of operational taxonomic units rather than resulting in an incorrect designation of new species.

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Neural Basis of Acoustic Species Recognition in a Cryptic Species Complex

10.1101/2021.08.25.457722 ◽

2021 ◽

Author(s):

Saumya Gupta ◽

Rishi K. Alluri ◽

Gary J. Rose ◽

Mark A. Bee

Keyword(s):

Reproductive Isolation ◽

Cryptic Species ◽

Temporal Processing ◽

Species Differences ◽

Species Recognition ◽

Species Difference ◽

Pulse Number ◽

Neural Basis ◽

Auditory Neurons ◽

Advertisement Calls

ABSTRACTSexual traits that promote species recognition are important drivers of reproductive isolation, especially among closely related species. Identifying neural processes that shape species differences in recognition is crucial for understanding the causal mechanisms of reproductive isolation. Temporal patterns are salient features of sexual signals that are widely used in species recognition by several taxa, including anurans. Recent advances in our understanding of temporal processing by the anuran auditory system provide an excellent opportunity to investigate the neural basis of species-specific recognition. The anuran inferior colliculus (IC) consists of neurons that are selective for temporal features of calls. Of potential relevance are auditory neurons known as interval-counting neurons (ICNs) that are often selective for the pulse rate of conspecific advertisement calls. Here, we took advantage of a species differences in temporal selectivity for pulsatile advertisement calls exhibited by two cryptic species of gray treefrog (Hyla chrysoscelis and Hyla versicolor) to test the hypothesis that ICNs mediate acoustic species recognition. We tested this hypothesis by examining the extent to which the threshold number of pulses required to elicit behavioral responses from females and neural responses from ICNs was similar within each species but potentially different between the two species. In support of our hypothesis, we found that a species difference in behavioral pulse number thresholds corresponded closely to a parallel species difference in neural pulse number thresholds. However, this relationship held only for ICNs that exhibited band-pass tuning for conspecific pulse rates. Together, these findings suggest that differences in temporal processing of a subset of ICNs provide a mechanistic explanation for reproductive isolation between two cryptic and syntopically breeding treefrog species.Summary StatementTemporal processing by a subset of midbrain auditory neurons plays key roles in decoding information about species identity in anurans.

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Taxonomic revision of the species of Colletes Latreille, 1802 (Hymenoptera: Colletidae: Colletinae) found in Chile

Zootaxa ◽

10.11646/zootaxa.4364.1.1 ◽

2017 ◽

Vol 4364 (1) ◽

pp. 1 ◽

Cited By ~ 7

Author(s):

RAFAEL R. FERRARI

Keyword(s):

New Species ◽

Cryptic Species ◽

Dna Barcoding ◽

Geographic Distribution ◽

Species Recognition ◽

Taxonomic Revision ◽

Junior Synonym ◽

Morphological Approach

A taxonomic revision of Colletes Latreille species with known geographic distribution in Chile is presented. In addition to the traditional morphological approach to taxonomy, DNA barcoding was employed to facilitate sexual association and cryptic species recognition. I provide diagnoses, synonymies, geographic and floral records, and a fully-illustrated key for 31 recognized species, 23 of them previously described: C. alocochila Moure, C. atacamensis Janvier, C. atripes Smith, C. bicolor Smith, C. chusmiza Rojas & Toro, C. cognatus Spinola, C. cyanescens (Haliday), C. cyaniventris Spinola n. stat., C. flaminii Moure, C. fulvipes Spinola, C. gilvus Vachal, C. guanta Rojas & Toro, C. longiceps Friese, C. lucens Vachal, C. mastochila Moure, C. murinus Friese, C. musculus Friese, C. nigritulus Friese, C. patagonicus Schrottky, C. quelu Rojas & Toro, C. rutilans Vachal, C. sulcatus Vachal, and C. vicugnensis Rojas & Toro. In addition, eight new species are described: C. arthuri n. sp., C. coquimbensis n. sp., C. flavipilosus n. sp., C. kuhlmanni n. sp., C. nigropilosus n. sp., C. simulatus n. sp., C. toroi n. sp., and C. ventricarinatus n. sp. Lectotypes for the following species are designated: Andrena cyanescens, Colletes bicolor, C. campoi Herbst, C. chubutensis Cockerell, C. gilvus, C. lucens, C. patagonicus, C. rufosignatus Cockerell, and C. viridans Vachal. Colletes seminitidus Spinola and C. viridans are both proposed as junior synonyms of C. cyanescens, and C. araucariae Friese is considered a junior synonym of C. sulcatus. Colletes cyaniventris n. stat. is resurrected from synonymy.

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Introduced marine macroalgae: new perspectives on species recognition and distribution in New Zealand

Botanica Marina ◽

10.1515/bot-2021-0042 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Wendy A. Nelson ◽

Roberta D’Archino ◽

Kate F. Neill ◽

Nestor M. Robinson

Keyword(s):

New Zealand ◽

Cryptic Species ◽

Species Recognition ◽

Data Availability ◽

Marine Macroalgae ◽

Indigenous Species ◽

Molecular Tools ◽

Non Indigenous Species ◽

The Impact

Abstract The recognition of non-indigenous marine macroalgae in New Zealand and the potential pathways and vectors contributing to their arrival were discussed by Nancy Adams in 1983 along with a list of 14 species she considered to be “possibly naturalised”. In the following 38 years many more species have been identified as non-indigenous, a few of which have become widespread and invasive around New Zealand. We present an updated list of 61 taxa that we consider to have been introduced to the archipelago, and highlight a range of issues associated with the recognition of non-indigenous species, particularly increased taxonomic knowledge, the impact of an expanded collection baseline, as well as targeted investigations in New Zealand, increasing data availability globally, and the role of molecular tools for confirming species identifications and distinguishing cryptic species.

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Identification of sibling species in the genus Eucyclops from water-bodies of Ukraine and Russia using crossbreeding studies

Ecology and Noospherology ◽

10.15421/031406 ◽

2014 ◽

Vol 25 (1-2) ◽

pp. 61-68 ◽

Cited By ~ 1

Author(s):

V. I. Monchenko ◽

L. P. Gaponova ◽

V. R. Alekseev

Keyword(s):

Cryptic Species ◽

River Basin ◽

Black Sea ◽

Species Complex ◽

River Basins ◽

Water Bodies ◽

Similar Species ◽

Basin Water ◽

Different Populations ◽

Baltic Sea Basin

Crossbreeding experiments were used to estimate cryptic species in water bodies of Ukraine and Russia because the most useful criterion in species independence is reproductive isolation. The problem of cryptic species in the genus Eucyclops was examined using interpopulation crosses of populations collected from Baltic Sea basin (pond of Strelka river basin) and Black Sea basin (water-reservoires of Dnieper, Dniester and Danube rivers basins). The results of reciprocal crosses in Eucyclops serrulatus-group are shown that E. serrulatus from different populations but from water bodies belonging to the same river basin crossed each others successfully. The interpopulation crosses of E. serrulatus populations collected from different river basins (Dnipro, Danube and Dniester river basins) were sterile. In this group of experiments we assigned evidence of sterility to four categories: 1) incomplete copulation or absence of copulation; 2) nonviable eggs; 3) absence of egg membranes or egg sacs 4) empty egg membranes. These crossbreeding studies suggest the presence of cryptic species in the E. serrulatus inhabiting ecologically different populations in many parts of its range. The same crossbreeding experiments were carries out between Eucyclops serrulatus and morphological similar species – Eucyclops macruroides from Baltic and Black Sea basins. The reciprocal crossings between these two species were sterile. Thus taxonomic heterogeneity among species of genus Eucyclops lower in E. macruroides than in E. serrulatus. The interpopulation crosses of E. macruroides populations collected from distant part of range were fertile. These crossbreeding studies suggest that E. macruroides species complex was evaluated as more stable than E. serrulatus species complex.

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