A new piece in the puzzle for the riverine slugs of the Acochlidiidae (Gastropoda: Panpulmonata: Acochlidimorpha) helps tracing steps of their freshwater invasion

AbstractGastropods (slugs and snails) are prominent and species-rich faunal elements in marine and terrestrial habitats of the tropics. While several clades of snails inhabit freshwater systems, slugs are extremely rare in freshwater: only the centimeter-sized Acochlidiidae, with currently three genera, contain more than one species and live in the lower reaches of island streams in an area comprising Eastern Indonesia, Fiji, and Palau. Where known, the species of this unique group are specialized predators of other amphidromous snails’ egg capsules (Neritidae) and their reproductive biology and adaptations to life in freshwater are complex. Acochlidiidae are thus of special interest for evolutionary biology and ecology. We here describe a new genus of unusually bluish-green acochlidiid to date known only from a single locality on the island of Ambon, Indonesia. Previous molecular data found this charismatic species to link slender Strubellia slugs with broad and flattened Acochlidium and Palliohedyle. We establish Wallacellia siputbiru n. gen. n. sp., the “blue slug” in Bahasa Indonesia, by using scanning electron microscopy of cuticular elements, light microscopy of serial semithin histological sections of the soft body, and 3D reconstruction of all organ systems based on these sections. Special structures of this seemingly rare endemic species include the enlarged kidney and the huge copulatory organ. Our data now clarify that, in the invasion of freshwater habitats in Acochlidiidae, sexual selection (the anterior three-part copulatory organ) preceded ecological selection (posterior flattened habitus with branched or multiplied internal organs).

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Complex diversity in a mainly tropical group of ant parasitoids: Revision of the Orasema stramineipes species group (Hymenoptera: Chalcidoidea: Eucharitidae)

Zootaxa ◽

10.11646/zootaxa.4401.1.1 ◽

2018 ◽

Vol 4401 (1) ◽

pp. 1 ◽

Cited By ~ 3

Author(s):

ROGER A. BURKS ◽

JOHN M. HERATY ◽

CHRYSALYN DOMINGUEZ ◽

JASON L. MOTTERN

Keyword(s):

Biological Control Agent ◽

Sister Group ◽

Molecular Data ◽

Species Group ◽

Control Agent ◽

Wasmannia Auropunctata ◽

Secondary Infections ◽

Tropical America ◽

Morphological And Molecular Data ◽

The Tropics

Twenty-nine species are recognized in the Orasema stramineipes species group, including 22 new species in what is now the most diverse species group of the New World ant-parasitoid genus Orasema Cameron. Orasema aenea Gahan syn. n. is synonymized with O. freychei (Gemignani), the holotype of which has been rediscovered. Orasema smithi Howard syn. n. is synonymized with Orasema minutissima Howard. Orasema violacea Gemignani syn. n. and its replacement name Orasema gemignanii De Santis syn. n. are synonymized with O. worcesteri (Girault). Twenty-two species are described as new: O. arimbome Dominguez, Heraty & Burks n. sp., O. carchi Heraty, Burks & Dominguez n. sp., and the following 20 species by Burks, Heraty & Dominguez: O. chunpi n. sp., O. cozamalotl n. sp., O. evansi n. sp., O. hyarimai n. sp., O. kaspi n. sp., O. kulli n. sp., O. llanthu n. sp., O. llika n. sp., O. mati n. sp., O. nyamo n. sp., O. pirca n. sp., O. pisi n. sp., O. qillu n. sp., O. qincha n. sp., O. rikra n. sp., O. taku n. sp., O. tapi n. sp., O. torrensi n. sp., O. woolleyi n. sp., and O. yaax n. sp. The stramineipes-group has much greater diversity in tropical America than outside the tropics, and is much more diverse than its sister-group, the susanae-group, which is mainly present in temperate regions of Argentina. A hypothesis of phylogenetic relationships is proposed based on an analysis of 28S-D2 rDNA and cytochrome oxidase I (COI) for 14 stramineipes-group species. Species concepts were established using both morphological and molecular data. Most species in the stramineipes-group have a tropical distribution, with only a few species in temperate regions. Ant hosts for the group include Pheidole Westwood, Wasmannia Forel, and possibly Solenopsis Westwood (Formicidae: Myrmicinae). Orasema minutissima is a common parasitoid of Wasmannia auropunctata Roger in the Caribbean and has the potential to be a biological control agent in other areas of the world. Two distinct size morphs are recognized for O. minutissima, which are correlated with attacking either Wasmannia (small morph) or different castes of Pheidole (medium to large size morphs). Some species of Orasema have been regarded as pests due to scarring or secondary infections of leaves or fruit of banana, yerba mate or blueberry, but outbreaks are rare and the threat is usually temporary.

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Revealing their innermost secrets: an evolutionary perspective on the disparity of the organ systems in anomuran crabs (Crustacea: Decapoda: Anomura)

Contributions to Zoology ◽

10.1163/18759866-08504001 ◽

2016 ◽

Vol 85 (4) ◽

pp. 361-386 ◽

Cited By ~ 5

Author(s):

Jonas Keiler ◽

Stefan Richter ◽

Christian S. Wirkner

Keyword(s):

Hydrothermal Vents ◽

Morphological Changes ◽

Direct Consequence ◽

Morphological Characters ◽

Last Common Ancestor ◽

Organ Systems ◽

Freshwater Habitats ◽

Chemosynthetic Bacteria ◽

Cladistic Analyses ◽

Morphological Transformations

The Southern Australian crustacean species Lomis hirta (Lomisoidea: Lomisidae) is a representative of one of the three anomuran taxa which obtained their crab-like habitus independently from each other. This process, the evolutionary transformation into a crab-like form, is termed carcinization. To shed light on the morphological changes which took place during carcinization and to investigate structural dependence (coherence) between external and internal morphological characters, we studied L. hirta and representatives of its putatively most closely related taxa, Aegla cholchol (Aegloidea: Aeglidae) and Kiwa puravida (Chirostyloidea: Kiwaidae). External and internal anatomy was studied using microcomputertomography and computer-aided 3D reconstruction. A. cholchol and K. puravida belong to equally exceptional lineages: Aegla is endemic to South America and lives in freshwater habitats; Kiwa is a deep sea dweller associated to chemosynthetic bacteria found in methane seeps or hydrothermal vents. On the basis of recent cladistic analyses we reconstruct the anatomical ground pattern of the squat lobster-like last common ancestor of the three taxa and trace the morphological transformations that affected inner and outer morphology in the recent forms. Our results show, among other things, that the pleon in Lomis underwent drastic modifications in the context of carcinization, including a reduction of the muscular portion leaving more room for the hepatopancreas and gonads, and a narrowing of the pleonal ganglia which became shifted anteriorly into the cephalothorax and attached to the cephalothoracic ganglion. We interpret these anatomical changes in Lomis to have come about because of the loss of the caridoid escape reaction, which in turn was a direct consequence of the evolution of a strongly bent pleon as part of the crab-like habitus, and of a hidden lifestyle.

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Open computational landscape genetics

10.7287/peerj.preprints.1721v1 ◽

2016 ◽

Author(s):

Stéphane Joost ◽

Solange Duruz ◽

Estelle Rochat ◽

Ivo Widmer

Keyword(s):

Population Genetics ◽

Landscape Genetics ◽

Evolutionary Biology ◽

Geographical Information Systems ◽

Information Science ◽

Molecular Data ◽

Geographic Information ◽

Research Field ◽

Environmental Data ◽

Geographical Information

Geographical Information Systems (GIS) are considered to be applications-led technology. Consequently, geographic information scientists commonly find themselves as guest in host disciplines in order to best exploit spatial analysis tools and methods, appropriately guided by experts in the field. An example is population genetics in evolutionary biology. Genetic information being linked to living organisms can be partially characterized by geographic coordinates. A research field named landscape genetics emerged at the intersection of genetics, environmental and geographic information science. Geocomputation and programming efforts carried out with the help of open sources technologies and dedicated to the analysis of genetic data gather together a key scientific community whose goal is to extract new knowledge from the present data tsunami caused by the advent of high throughput molecular data and of new sources of high resolution environmental data. While the level of sophistication of the population genetics functions included in the analytical frameworks developed until now are cutting-edge, advanced geo-competences are also required to reinforce the spatial side of this discipline. They will be particularly useful in conservation programmes for wildlife preservation, but also in farm animal genetic resources conservation.

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Morphology and molecular characterization of Demidospermus spirophallus n. sp., D. prolixus n. sp. (Monogenea: Dactylogyridae) and a redescription of D. anus in siluriform catfish from Brazil

Journal of Helminthology ◽

10.1017/s0022149x17000256 ◽

2017 ◽

Vol 92 (2) ◽

pp. 228-243 ◽

Cited By ~ 11

Author(s):

L. Franceschini ◽

A.C. Zago ◽

M.I. Müller ◽

C.J. Francisco ◽

R.M. Takemoto ◽

...

Keyword(s):

Molecular Characterization ◽

Accessory Piece ◽

Copulatory Organ ◽

Molecular Data ◽

Neotropical Region ◽

Morphological Characterization ◽

Ribosomal Gene ◽

Upper Paraná River Floodplain ◽

Morphological And Molecular Data

AbstractThe present study describes Demidospermus spirophallus n. sp. and Demidospermus prolixus n. sp. (Monogenea, Dactylogyridae) from the siluriform catfish Loricaria prolixa Isbrücker & Nijssen, 1978 (Siluriformes, Loricariidae) from the state of São Paulo, Brazil, supported by morphological and molecular data. In addition, notes on the circumscription of the genus with a redescription of Demisdospermus anus are presented. Demidospermus spirophallus n. sp. differed from other congeners mainly because of the morphology of the male copulatory organ (MCO), which exhibited 2½ counterclockwise rings, a tubular accessory piece with one bifurcated end and a weakly sclerotized vagina with sinistral opening. Demidospermus prolixus n. sp. presents a counterclockwise-coiled MCO with 1½ rings, an ovate base, a non-articulated groove-like accessory piece serving as an MCO guide, two different hook shapes, inconspicuous tegumental annulations, a non-sclerotized vagina with sinistral opening and the absence of eyes or accessory eyespots. The present study provides, for the first time, molecular characterization data using the partial ribosomal gene (28S) of two new species of Demidospermus from Brazil (D. spirophallus n. sp. and D. prolixus n. sp.), and Demidospermus anus from Loricariichthys platymetopon Isbrücker & Nijssen, 1979 collected in the Upper Paraná River floodplain, Brazil. Additionally, a revision of the species composition of this genus and others that occur in catfish is proposed to elucidate problems with their circumscription. The Brazilian species of Demidospermus clustered together as sister taxa among Neotropical dactylogyrids from siluriforms. The morphological characterization of D. spirophallus n. sp. and D. prolixus n. sp., and the molecular data of the three species in the present study will extend knowledge about this monogenean genus from the Neotropical region, and provide new information for future phylogeny studies.

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Open computational landscape genetics

10.7287/peerj.preprints.1721v3 ◽

2016 ◽

Author(s):

Stéphane Joost ◽

Solange Duruz ◽

Estelle Rochat ◽

Ivo Widmer

Keyword(s):

Population Genetics ◽

Landscape Genetics ◽

Evolutionary Biology ◽

Geographical Information Systems ◽

Information Science ◽

Molecular Data ◽

Geographic Information ◽

Research Field ◽

Environmental Data ◽

Geographical Information

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The evolutionary history of Stomatopoda (Crustacea: Malacostraca) inferred from molecular data

PeerJ ◽

10.7717/peerj.3844 ◽

2017 ◽

Vol 5 ◽

pp. e3844 ◽

Cited By ~ 10

Author(s):

Cara Van Der Wal ◽

Shane T. Ahyong ◽

Simon Y.W. Ho ◽

Nathan Lo

Keyword(s):

Phylogenetic Analyses ◽

Sister Group ◽

Molecular Data ◽

Recent Common Ancestor ◽

Ancestral State ◽

Crown Group ◽

Most Recent Common Ancestor ◽

History Of ◽

The Tropics ◽

Age Constraints

The crustacean order Stomatopoda comprises seven superfamilies of mantis shrimps, found in coastal waters of the tropics and subtropics. These marine carnivores bear notable raptorial appendages for smashing or spearing prey. We investigated the evolutionary relationships among stomatopods using phylogenetic analyses of three mitochondrial and two nuclear markers. Our analyses recovered the superfamily Gonodactyloidea as polyphyletic, withHemisquillaas the sister group to all other extant stomatopods. A relaxed molecular clock, calibrated by seven fossil-based age constraints, was used to date the origin and major diversification events of stomatopods. Our estimates suggest that crown-group stomatopods (Unipeltata) diverged from their closest crustacean relatives about 340 Ma (95% CRI [401–313 Ma]). We found that the specialized smashing appendage arose after the spearing appendage ∼126 Ma (95% CRI [174–87 Ma]). Ancestral state reconstructions revealed that the most recent common ancestor of extant stomatopods had eyes with six midband rows of hexagonal ommatidia. Hexagonal ommatidia are interpreted as plesiomorphic in stomatopods, and this is consistent with the malacostracan ground-plan. Our study provides insight into the evolutionary timescale and systematics of Stomatopoda, although further work is required to resolve with confidence the phylogenetic relationships among its superfamilies.

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Phenotypic flexibility of the avian gizzard: rapid, reversible and repeated changes of organ size in response to changes in dietary fibre content

Journal of Experimental Biology ◽

10.1242/jeb.202.22.3171 ◽

1999 ◽

Vol 202 (22) ◽

pp. 3171-3179 ◽

Cited By ~ 5

Author(s):

J.M. Starck

Keyword(s):

Japanese Quail ◽

Evolutionary Biology ◽

Time Lag ◽

Coturnix Japonica ◽

Control Group ◽

Phenotypic Flexibility ◽

Organ Systems ◽

Group 2 ◽

Dietary Fibre Content ◽

Phenotypic Responses

Evolutionary biology presumes that organ capacities match their natural loads. Therefore, in fluctuating conditions, organ systems are expected to show a reversible, repeatable and rapid phenotypic response that is directional and scaled. In this study, phenotypic responses of the gizzard of adult Japanese quail (Coturnix japonica) to experimental mismatches of load and capacity were tested by a series of diet-switching experiments, involving an increased content of non-digestable fibre (NDF) in the diet. The results of all experiments were in accordance with the predictions of the hypothesis that there is matching between loads and capacities. (1) The observed phenotypic responses are directional and scaled to the demands, i.e. increasing NDF elicits an increase in gizzard size. When the proportion of NDF in the diet was raised from 1 % to 45 %, the gizzard was more than twice as large as in the control group. (2) Size responses were reversible, and reduced NDF was followed by a decrease of gizzard size. (3) Phenotypic responses could be elicited repeatedly in three successive trials. (4) Excess capacities were downregulated and insufficient capacities were upregulated. (5) The responses followed changes of loads with almost no time lag, with size changes measurable within 24 h.

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Predicting Global Biodiversity Patterns from Theory

A Theory of Global Biodiversity (MPB-60) ◽

10.23943/princeton/9780691154831.003.0005 ◽

2018 ◽

pp. 124-148

Author(s):

Boris Worm ◽

Derek P. Tittensor

Keyword(s):

Species Richness ◽

Theoretical Model ◽

Deep Sea ◽

Global Theory ◽

Equal Area ◽

Terrestrial Habitats ◽

Global Biodiversity ◽

Declining Species ◽

The Tropics

The previous chapter developed a global theory of biodiversity incorporating gradients in ambient temperature and habitat area or productivity. It showed that a metacommunity model implementation of the theory can reproduce first-order patterns of declining species richness from the tropics to the poles in an idealized cylindrical ocean. This chapter tests the theory in a more realistic setting by fitting the neutral-metabolic metacommunity model to a global equal-area grid with a more realistic spatial structure. The rationale here is to explore whether the communities that evolve in a simple theoretical model can reproduce observed patterns of species richness in the real world, and reconcile the contrasting patterns seen in coastal, pelagic, deep-sea, and terrestrial habitats.

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Improved heat tolerance in air drives the recurrent evolution of air-breathing

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.2927 ◽

2014 ◽

Vol 281 (1782) ◽

pp. 20132927 ◽

Cited By ~ 35

Author(s):

Folco Giomi ◽

Marco Fusi ◽

Alberto Barausse ◽

Bruce Mostert ◽

Hans-Otto Pörtner ◽

...

Keyword(s):

Thermal Tolerance ◽

Evolutionary Biology ◽

High Water ◽

Aerobic Performance ◽

Air Breathing ◽

Thermal Niche ◽

Key Innovation ◽

Animal Phyla ◽

The Tropics ◽

Environmental Temperatures

The transition to air-breathing by formerly aquatic species has occurred repeatedly and independently in fish, crabs and other animal phyla, but the proximate drivers of this key innovation remain a long-standing puzzle in evolutionary biology. Most studies attribute the onset of air-breathing to the repeated occurrence of aquatic hypoxia; however, this hypothesis leaves the current geographical distribution of the 300 genera of air-breathing crabs unexplained. Here, we show that their occurrence is mainly related to high environmental temperatures in the tropics. We also demonstrate in an amphibious crab that the reduced cost of oxygen supply in air extends aerobic performance to higher temperatures and thus widens the animal's thermal niche. These findings suggest that high water temperature as a driver consistently explains the numerous times air-breathing has evolved. The data also indicate a central role for oxygen- and capacity-limited thermal tolerance not only in shaping sensitivity to current climate change but also in underpinning the climate-dependent evolution of animals, in this case the evolution of air-breathing.

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Cyanobacteria Phylogenetic Studies Reveal Evidence for Polyphyletic Genera from Thermal and Freshwater Habitats

Diversity ◽

10.3390/d12080298 ◽

2020 ◽

Vol 12 (8) ◽

pp. 298

Author(s):

Rita Cordeiro ◽

Rúben Luz ◽

Vitor Vasconcelos ◽

Vítor Gonçalves ◽

Amélia Fonseca

Keyword(s):

North Atlantic Ocean ◽

Extreme Environments ◽

Morphological Characteristics ◽

Taxonomic Revision ◽

Environmental Data ◽

New Genera ◽

Environmental Distribution ◽

The North ◽

Freshwater Habitats ◽

Terrestrial Habitats

Cyanobacteria are among the most diverse morphological microorganisms that inhabit a great variety of habitats. Their presence in the Azores, a volcanic archipelago of nine islands in the middle of the North Atlantic Ocean, has already been reported. However, due to the high diversity of cyanobacteria habitats, their biodiversity is still understudied, mainly in extreme environments. To address this, a total of 156 cyanobacteria strains from Azores lakes, streams, thermal and terrestrial habitats were isolated. Identification was made based on a polyphasic approach using classical taxonomy (morphological characteristics and environmental data) and phylogeny among 81 strains assessed by maximum likelihood and Bayesian analysis of 16S rDNA partial sequences. The 156 isolates showed a high genera diversity (38) belonging to the orders Chroococcales, Nostocales, Oscillatoriales, and Synechococcales. Eleven new genera for the Azores habitats are here reported, reinforcing that cyanobacteria biodiversity in these islands is still much understudied. Phylogenetic analysis showed 14 clusters associated with these cyanobacteria orders, with evidence for six new genera and valuable information towards Microchaete/Coleospermum taxonomic revision that better reflects species environmental distribution. These results emphasize the need for cyanobacteria taxonomy revisions, through polyphasic studies, mainly in Synechococcales order and in the Microchaete/Coleospermum, Nostoc, and Anabaena genera.

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