Cryptic Habitats Research Articles

Chromatic polymorphism in Trichomycterus albinotatus (Siluriformes, Trichomycteridae), a mountain catfish from south-eastern Brazil and the role of colouration characters in trichomycterine taxonomy

Colouration is an important tool for systematists inferring species limits and phylogenetic relationships of teleost fishes, but the use of colouration variation in trichomycterine catfish systematics has generated some controversy. We first report and describe the occurrence of four, geographically disjunct colour morphs inTrichomycterus albinotatus, endemic to south-eastern Brazil, as well as ontogenetic colouration change in each morph. A phylogenetic analysis using a cytb fragment (1098 bp) for 23 specimens representing all colour morphs and four outgroups did not support any correlation between colour morphs and lineages, with different colour morphs sharing identical haplotypes. This study indicated that young adult specimens found in lighter habitats had white and brown to black spots on the flank, whereas similar-sized specimens inhabiting darker habitats had white spots inconspicuous or absent and dark brown or black spots expanded. Individuals above about 65 mm SL of all populations had flank white marks less conspicuous or absent and cryptic habits during daylight, contrasting with smaller individuals with white marks and actively swimming above the substrate. Literature data indicate that ontogenetic colouration and habit changes occur in different trichomycterid lineages. Our data thus show that colouration may be problematic in taxonomical studies, although often being consistently used to diagnose species and clades. We conclude that colouration should not be discarded a priori as evidence of trichomycterine relationships and species limits, but should be used with caution in systematic studies, being necessary additional evidence, such as osteological characters or molecular data.

Ovarian cycle, reproductive performance and breeding seasonality of Amazonian yellow-footed tortoises (Chelonoidis denticulatus) in the wild

Studies of the reproductive functional morphology of chelonians are important to understand the reproductive physiology, anatomy, and endocrinology of these species. However, data on the reproduction of this group have been difficult to obtain because of their cryptic habits and as a result the consequent inefficiency of conventional field methods in detecting individuals in the wild. In this study, we obtained reproductive organs from 347 adult female yellow-footed tortoises (Chelonoidis denticulatus), one of the most hunted and traded land vertebrates in South America, donated by local sellers in a wild meat market in the Peruvian Amazon. We described the species’ reproductive cycle and the influence of climatic factors on reproductive performance. Of the sampled females, 116 (33.4%) were gravid and 231 (66.6%) were non-gravid, including 215 vitellogenic (62.0%) and 16 non-vitellogenic (4.6%). The mean number of ovarian follicles per female declined from 28.5 (<10 mm diameter), to 7.1 follicles (20–40 mm) to 3.2 follicles> 40 mm. Gravid females had in average 3.7 shelled eggs in the oviduct, with a mean egg diameter of 53.7 mm. The estimated annual reproductive potential in gravid females was 5.1 eggs per clutch, ranging from one to 22 eggs. There was a strong positive relationship between the diameter of shelled eggs and the straight carapace length of gravid females. The final phase of the folicular growth, the most demanding energetic process in chelonian reproduction, correlated with annual rainfall peak, while oviposition was estimated to occur in the dry season. The yellow-footed tortoise should be considered an opportunistic seasonal breeder, though capable of reproducing throughout the year. Reproductive yields are linked to climatic events that influence food availability in the environment. To improve the sustainable use of this species, adult females should be harvested primarily during reproductive quiescence, from the end of the laying period in the late dry season to the mid-rainy season when large follicles appear, to avoid taking gravid females. Our results are useful not just to better understand the reproductive biology of terrestrial chelonians but can inform the conservation management of harvested species.

Phylogeny and systematics of Sphaeriusidae (Coleoptera: Myxophaga): minute living fossils with underestimated past and present‐day diversity

AbstractSphaeriusidae (Coleoptera: Myxophaga) is a group of shiny, blackish and hemispherical riparian beetles, known for their miniaturized bodies. They are worldwide in distribution, but very limited information is available about taxonomic and morphological diversity, and natural and evolutionary history. The aim of this study is to help fill in these gaps. We examined the external morphology of modern representatives using scanning electron microscopy (SEM), and reconstructed the phylogeny of the family using five DNA markers (cytochrome oxidase I, 18S rRNA, 28S rRNA, CAD and wingless). Our results suggest a larger morphological diversity than previously expected, corresponding to the deep genetic divergences of principal lineages. We also examined two inclusions in 99‐million‐year‐old Burmese amber. The integration of all evidence allows us to recognize three genera: the extinct genus †Burmasporum Kirejtshuk, the newly defined genus Bezesporum gen.nov. preserved in Burmese amber (B. burmiticum sp.nov.) and present in the modern fauna of Southeast Asia, and the genus Sphaerius Waltl with a world‐wide distribution. Sphaerius species are morphologically highly uniform, with the exception of species from Australia and South Africa, which share some characteristics with Bezesporum gen.nov. despite being resolved as deeply nested lineages of Sphaerius by DNA data. The presence of Bezesporum gen.nov. in Burmese amber and in recent fauna indicates that Sphaeriusidae largely maintained their specific morphology and specialized riparian lifestyle for at least 100 million years. Therefore, they can be considered an exceptionally conserved group, with a minimum of evolutionary changes over a long period. Our study also demonstrates that the species numbers and fine‐scale morphological diversity of Sphaeriusidae are larger than expected in both the past and present‐day faunas. Both were apparently underestimated due to the minute body size and cryptic habits of these beetles.

A sterile insect technique pilot trial on Captiva Island: defining mosquito population parameters for sterile male releases using mark–release–recapture

BackgroundThe sterile insect technique (SIT), which involves area-wide inundative releases of sterile insects to suppress the reproduction of a target species, has proven to be an effective pest control method. The technique demands the continuous release of sterilized insects in quantities that ensure a high sterile male:wild male ratio for the suppression of the wild population over succeeding generations.MethodsFor these releases, it is important to determine several ecological and biological population parameters, including the longevity of the released males in the field, the dispersal of the released males and the wild pest population size. The Lee County Mosquito Control District initiated a study in a 47-ha portion of Captiva Island (Florida, USA), an island with a total area of 230 ha, to define biological SIT parameters for Aedes aegypti (L.), an invasive disease-vectoring mosquito known to be difficult to control due to a combination of daytime biting activity, use of cryptic breeding habitats that are difficult to target with conventional night-time ultra-low volume methods, and emerging resistance to commonly used insecticides. Another goal was to assess patterns of dispersal and survival for laboratory-reared sterile Ae. aegypti males released over time in the pilot site. These parameters will be used to evaluate the efficacy of a SIT suppression program for Ae. aegypti on Captiva Island.ResultsOver the course of seven mark-release-recapture studies using single- and multiple-point releases, 190,504 sterile marked males were released, for which the recapture rate was 1.5% over a mean period of 12 days. The mean distance traveled by sterile males of the local strain of Ae. aegypti that has colonized Captiva Island was 201.7 m from the release point, with an observed maximum traveled distance of 404.5 m. The released sterile mosquitoes had a probability of daily survival of 0.67 and an average life expectancy of ~ 2.46 days.ConclusionsThese data together with the population size estimate and sterile:wild ratio provide a solid basis for planning the SIT operational phase which is aimed at mosquito population suppression.Graphical abstract

Ecological succession of the sponge cryptofauna in Hawaiian reefs add new insights to detritus production by pioneering species

Successional theory proposes that fast growing and well dispersed opportunistic species are the first to occupy available space. However, these pioneering species have relatively short life cycles and are eventually outcompeted by species that tend to be longer-lived and have lower dispersal capabilities. Using Autonomous Reef Monitoring Structures (ARMS) as standardized habitats, we examine the assembly and stages of ecological succession among sponge species with distinctive life history traits and physiologies found on cryptic coral reef habitats of Kāneʻohe Bay, Hawaiʻi. Sponge recruitment was monitored bimonthly over 2 years on ARMS deployed within a natural coral reef habitat resembling the surrounding climax community and on ARMS placed in unestablished mesocosms receiving unfiltered seawater directly from the natural reef deployment site. Fast growing haplosclerid and calcareous sponges initially recruited to and dominated the mesocosm ARMS. In contrast, only slow growing long-lived species initially recruited to the reef ARMS, suggesting that despite available space, the stage of ecological succession in the surrounding habitat influences sponge community development in uninhabited space. Sponge composition and diversity between early summer and winter months within mesocosm ARMS shifted significantly as the initially recruited short-lived calcareous and haplosclerid species initially recruit and then died off. The particulate organic carbon contribution of dead sponge tissue from this high degree of competition-free community turnover suggests a possible new component to the sponge loop hypothesis which remains to be tested among these pioneering species. This source of detritus could be significant in early community development of young coastal habitats but less so on established coral reefs where the community is dominated by long-lived colonial sponges.

Integrated Pest Management of Wireworms (Coleoptera: Elateridae) and the Rhizosphere in Agroecosystems.

Simple SummaryThe name ‘wireworm’ refers to the subterranean larvae of click beetle (Coleoptera: Elateridae) species, of which several are serious pests of a wide range of crops. The limited effectiveness of the available insecticides, their wide host range, their long life cycle, and their cryptic subterranean habitat make wireworms a challenging pest to control. Integrated pest management (IPM) strategies have been recommended to reduce wireworm damage. Although IPM is generally considered to be an approach that is relatively more compatible with the environment and non-target organisms, the implementation of some of the tactics of managing subterranean wireworms is expected to induce stress in the rhizosphere and the established ecological interactions within, some of which could negatively impact various soil health parameters and, subsequently, plant growth. In this paper, we highlight some of the IPM tactics against wireworms and their effects on the rhizosphere and soil microbiome. Awareness of the potential impacts of IPM approaches to the management of subterranean pests will help professionals to develop and implement IPM strategies that minimize disturbance in the rhizosphere and support agroecosystem sustainability.The rhizosphere is where plant roots, physical soil, and subterranean organisms interact to contribute to soil fertility and plant growth. In agroecosystems, the nature of the ecological interactions within the rhizosphere is highly dynamic due to constant disruptions from agricultural practices. The concept of integrated pest management (IPM) was developed in order to promote an approach which is complementary to the environment and non-target organisms, including natural enemies, by reducing the sole reliance on synthetic pesticides to control pests. However, some of the implemented integrated cultural and biological control practices may impact the rhizosphere, especially when targeting subterranean pests. Wireworms, the larval stage of click beetles (Coleoptera: Elateridae), are generalist herbivores and a voracious group of pests that are difficult to control. This paper introduces some existing challenges in wireworm IPM, and discusses the potential impacts of various control methods on the rhizosphere. The awareness of the potential implications of different pest management approaches on the rhizosphere will assist in decision-making and the selection of the control tactics with the least long-term adverse effects on the rhizosphere.

An Approach to Assessing Zoo Animal Welfare in a Rarely Studied Species, the Common Cusimanse Crossarchus obscurus

Objective welfare assessments play a fundamental role in ensuring that positive welfare is achieved and maintained for animals in captivity. The Animal Welfare Assessment Grid (AWAG), a welfare assessment tool, has been validated for use with a variety of both domestic and exotic species. It combines both resource- and animal-based measures but relies heavily on knowledge of the species to effectively assess welfare. Many zoo species are understudied in the wild due to their cryptic nature or habitat choice; therefore, the published literature needs to be supported with captive behavioural observations and zoo records. Here we adapted previously published AWAG templates to assess the welfare of Crossarchus obscurus. A total of 21 factors were identified, and the final template was used to retrospectively score the welfare of two male and two female C. obscurus at Marwell Zoo, UK, validating the use of this process for preparing a welfare assessment for a species where the published literature is scarce.

Cascading impacts of a climate-driven ecosystem transition intensifies population vulnerabilities and fishery collapse

The recent large-scale intensification of marine heatwaves, and other climate-related stressors, has dramatically impacted biogenic habitats around the globe, including marine ecosystems such as coral reefs, seagrasses, and kelp forests. While the impacts to foundation species may be of particular concern, these ecological catastrophes underscore the need to examine how whole systems respond to a suite of stressors. The recent climate-driven collapse of the bull kelp forest and recreational red abalone fishery in northern California provides an example of unanticipated ripple and lagged effects in the system, intensifying vulnerabilities and accelerating population and fishery collapse. For this case study, we examined 15 years (2003–2018) of biological survey data on the bull kelp forest ecosystem—before, during, and after an extreme climate event. We document the interactions and complexity of impacts over time, as well as the resulting increased vulnerability of red abalone to additional anthropogenic, biological, and environmental stressors. We observed progressively stronger population-level responses of the red abalone to the marine heatwave and the regional loss of kelp, driving the movement of adults and juveniles in search of food. As food remained scarce, we documented the loss of productivity with diminished gonad and body condition, the absence of larval or newly-settled abalone, mass mortalities, and shoreward shifts in depth distributions. With 40% of the population dead or dying, juvenile and trophy-sized abalone abandoning cryptic habitats, the shift in the distribution to shallower depths increased the vulnerability of red abalone to the fishery. Other anthropogenic, biological, and climate-related stressors that disproportionately impact shallow habitats are now a growing concern for the survivors. For red abalone, previously unanticipated cascading risks include increased wave energy, warming air temperatures, freshwater flooding, landslides, as well as possible oil spills and harmful algal blooms. Climate-driven changes in vulnerability to fishing and environmental stressors present significant challenges for sustainable natural resource management in dynamic stressed systems, and underscore the need for continued system-focused monitoring. We present a conceptual framework supporting similar ecosystem investigations of recent and future climate impacts to inform adaptive ecosystem-based management strategies.

Rapid range expansion of an invasive flatworm, Kontikia andersoni, on sub-Antarctic Macquarie Island

Spanning the Southern Ocean high latitudes, Sub-Antarctic islands are protected areas with high conservation values. Despite the remoteness of these islands, non-native species threaten native species and ecosystem function. The most ubiquitous and speciose group of non-native species in the region are invertebrates. Due to their cryptic habits and ambiguous establishment history, the impacts of non-native invertebrates on native species and ecosystems in the region remains largely unknown. Understanding how non-native invertebrate species are transported, disperse, establish and colonise new habitats is key to understanding their existing and future impacts. This research is fundamental to improving biosecurity practise and informing future management of Southern Ocean islands. We undertook invertebrate surveys on Macquarie Island to determine the current status of four non-native macro-invertebrates—Kontikia andersoni and Arthurdendyus vegrandis (Platyhelminthes: Geoplanidae), Styloniscus otakensis (Isopoda: Styloniscidae) and Puhuruhuru patersoni (Amphipoda: Talitridae). Arthurdendyus vergrandis was not intercepted in our surveys, while we found S. otakensis and P. patersoni had not expanded their range. In contrast, K. andersoni has more than doubled its previously mapped area and expanded at a rate of ~ 500 m-yr since 2004. We discuss the possible underlying mechanisms for the dramatic range expansion of K. andersoni and consider the implications for the future management of Macquarie Island.

Nectar Source and Pollinator Cross Contamination and Persistence of Pyriproxyfen Associated with the Use of Autodissemination Techniques for Mosquito Control.

Controlling container inhabiting mosquitoes such as Aedes aegypti and Ae. albopictus is often difficult because of the requirement to treat small and inaccessible cryptic sources of water where larvae are located. Autodissemination approaches based on the dissemination of insect growth regulators (IGRs) have been demonstrated as an effective means to treat these cryptic larval habitats and provide population control. Autodissemination approaches are attractive because they are based on the mosquitoes disseminating small amounts of IGRs compared to more traditional insecticide applications. While dissemination of small amounts of IGRs seems like an advantage, these approaches could lead to unintended transfer and effects on nontarget insect pollinators by delivering highly potent IGRs to nectar sources. Here we looked for the indirect and direct transfer of pyriproxyfen (PPF) to natural and artificial nectar sources and painted lady butterflies, Vanessa cardui, in semifield cages using the release of treated Ae. albopictus males or an autodissemination station. We also performed persistence tests of PPF in oviposition containers and natural and artificial nectar sources when exposed to laboratory and natural conditions. The data suggest that there is direct and indirect transfer to nectar sources and V. cardui associated with the use of autodissemination approaches. We discuss the results in the context of using autodissemination approaches for mosquito control and the potential risks these approaches may pose to nontarget insect pollinators.

The Entomopathogenic Nematodes H. bacteriophora and S. carpocapsae Inhibit the Activation of proPO System of the Nipa Palm Hispid Octodonta nipae (Coleoptera: Chrysomelidae).

Entomopathogenic nematodes are biocontrol agents of invasive insect pests in soil and cryptic habitats. Nipa palm hispid, Octodonta nipae, is a pest of palm trees in Sothern China. To address its increasing damage, environmentally friendly control methods are required. This study aimed to test efficacy of Heterorhabditis bacteriophora and Steinernema carpocapsae on O. nipae and investigated the influence of secondary metabolites, nematodes, and their isolated cuticles on the activation of O. nipae’s prophenoloxidase system using qPCR analysis. Our data revealed that O. nipae were less susceptible to H. bacteriophora than S. carpocapsae and penetrations of infective juveniles were higher with S. carpocapsae treatment than H. bacteriophora. Moreover, expression levels of the serine protease P56, prophenoloxidase activation factor 1, PPO and serine protease inhibitor 28 upon S. carpocapsae and H. bacteriophora infections were generally downregulated at all times. However, upon heating, the cuticles lost their inhibitory effects and resulted in upregulation of the PPO gene. Similarly, the addition of arachidonic acid reversed the process and resulted in the upregulation of the PPO gene compared to the control. Further work is needed to identify toxic substances secreted by these EPNs to evade O. nipae’s immune system.

Molecular survey of Cryptoplax japonica (Polyplacophora: Cryptoplacidae) reveals cryptic lineages in the northwestern Pacific

ABSTRACT The chiton genus Cryptoplax is widely distributed in the Indo-Pacific, extending to southern Australia and the northwestern Pacific (NWP), with 17 recognized species. Among these species, Cryptoplax japonica is commonly found on rocky intertidal and subtidal substrates in the NWP, whereas another species, C. propior, is rarely seen because of its cryptic subtidal habitat and limited distribution. In this study, we surveyed the genetic diversity of C. japonica populations based on 93 individuals from 24 sampling sites along the Korean and Japanese coastlines, including the type locality, using DNA sequences of the mitochondrial gene cytochrome c oxidase subunit I (COI). Haplotype network and phylogenetic analyses of COI sequences revealed two highly divergent genetic lineages of C. japonica separated by a large pairwise genetic distance (10.62%), which was comparable to the genetic difference when either of these two lineages (A or B) is compared with the co-occurring C. propior. In addition to COI sequences, average sequence divergence in 16S rDNA between these three lineages ranged from 2.0 to 3.3%. In contrast to this deep sequence divergence, both morphological examination of radula, girdle and articulamentum colouring, and morphometric analyses of shell measurements using principal component analysis and linear discriminant analysis revealed no diagnostic differences between the two C. japonica lineages. The co-occurrence of these two divergent lineages within most of our studied area, with no morphological differences, indicates cryptic divergence. More extensive sampling from the entire distributional ranges of these cryptic species, in combination with the use of additional molecular markers could shed light on the mechanisms underlying their divergence.

Diversity of holothuroidea by spicule type in the intertidal zone of Sepanjang Beach, Gunungkidul, Yogyakarta

Holothuroidea are common individuals of benthic communities in numerous marine biological systems. They work as supplement recyclers and bioturbators of delicate bottoms and are preyed upon by fishes, birds, mollusks, crustaceans, and other taxa. Sepanjang Beach has a coral community composed of coral reefs and dominated by algae in the surface, which is a habitat for a variety of complex and diverse benthic invertebrates, one of which is holothuroidea. However, little is known about the diversity of holothurians in the area. From 2014 to 2015 there were 5 species found on Sepanjang coast, namely Holothuria leucospilota, Actinopyga echinites, Stichopus horren, Holothuria scabra, and Holothuria hilla. Samples were collected on June 9, 2021 at Sepanjang Beach using the purposive random sampling method and identified based on the type of spicules taken on the dorsal and ventral integument. The results obtained found 7 species, namely Holothuria papilifera, Holothuria cinerascens, Holothuria impatiens, Holothuria pardalis, Actinopyga miliaris, Holothuria hilla, and Actinopyga sp. The absence of previous records of these species may be associated with their low densities and cryptic habits. This research acts to fill knowledge about distribution and diversity of holothurians in the south coast of java island, especially Sepanjang beach, Gunungkidul, Yogyakarta.

Biospeleothems Formed by Fungal Activity During the Early Holocene in the “Salar de Uyuni”

The Chiquini and Galaxias caves contain speleothems that are templated by long fungal structures. They have been associated with the carbonate lacustrine deposits in the margins of the Coipasa and Uyuni Salar basins. During a wetter episode, such carbonates formed at the end of the last glaciation raising the lake level to more than 100 m in the Tauca events (15–12 ky). Such an event flooded the caves that eventually became a cryptic habitat in the lake. The caves show bizarre speleothems framed by large (>1 m) fungal buildings covering the older algal mineralized structures. Although the origin of the caves is not fully understood, the occurrence of two carbonatic units with very distinctive fabric suggests that they formed in two separated humid events. In this regard, the mineralized algal structures, showing the same features as the lacustrine carbonates, likely formed during the Tauca flooding events in the terminal Pleistocene that inundated older caves. The different caves were exposed to the atmosphere after a drop in the lake level that promoted alluvial erosion by <12–10 ky (Ticaña episode) under arid conditions. A last humid episode rising the lake surface 10 m above the Salar level, which was not enough to inundate the caves a second time, drove the formation of the biospeleothems by fungi biomineralization. The abundance and size of the preserved fungal structures suggest that they were sustained by a stable hydrological activity plus a constant organic supply. While nutrients could have been primarily sourced from the vegetal communities that occupied the exhumated lake margins, they might have also been released from the lacustrine carbonatic unit. The combination of hydrology and biological activities were likely determinants for a fast rock dissolution and mineralization ending in the construction of the fungal biospeleothems.

A taxonomic revision of the dirt ants, Basiceros Schulz, 1906 (Hymenoptera, Formicidae).

The ant genus Basiceros is an exclusively Neotropical group known for its cryptic habits. Based on a recent molecular phylogenetic framework, a comprehensive revisionary study of the genus is presented. Nine species are recognized, two of which are described as new (Basiceros browni sp. nov. and Basiceros tumucumaquensis sp. nov.). Basiceros redux (Donisthorpe 1939) is transferred to the genus Octostruma (O. reducta comb. nov.). As part of this revisionary work, taxonomic keys and images to all species and castes are provided. Castes and sexes (including larvae, males, and intercastes) are described for the first time for several Basiceros species. New records considerably expand the distributional range for most species. Natural history data and comments on character plasticity and convergence are also included.

Integrative taxonomy confirms the presence of the enigmaticLysmata olavoiFransen, 1991 (Decapoda: Lysmatidae) in the Mediterranean Sea

AbstractThe genusLysmataRisso, 1816 includes five species in the Mediterranean Sea, namely two well-known species with an Atlantic–Mediterranean distribution,L. seticaudata(Risso, 1816) andL. nilitaDohrn &amp; Holthuis, 1950, and three additional species only known from single records. These areL. kempiChace, 1997 andL. vittata(Stimpson, 1860), alien species native to the Indo-Pacific region, andL. olavoiFransen, 1991, a poorly known species originally described from the Azores (Atlantic Ocean) and only reported three decades ago from the eastern parts of the basin. Based on an integrative taxonomic approach, we report the first finding of an ovigerous female ofL. olavoifrom Italy (Gulf of Naples, Tyrrhenian Sea) and the entire western Mediterranean, thus confirming the presence of this species in the basin and filling a wide gap in its published distribution. It is possible that this taxon was present in the Mediterranean for centuries but went overlooked or undetected due to cryptic habits, occupancy of still unexplored habitats, or misidentification with the highly similarL. seticaudata. Results of phylogenetic analyses confirm the exclusion ofL. olavoiby the major lysmatid groups and underline the necessity of multilocus approaches to disentangle its correct phylogenetic position. As the species is still surrounded by a number of unsolved ecological and phylogenetic questions, further field and laboratory work is required to shed light on them.

Oogenesis and embryogenesis in a cryptogenic species of calcareous sponge (Calcaronea, Heteropiidae) in the southwestern Atlantic

AbstractCalcarea is a diverse group of sponges, in which individuals are generally small and found in cryptic habitats. These characteristics hamper the access to them and, consequently, the knowledge about several aspects of their biology, including reproduction. Little is known about many reproductive aspects of these sponges and broad generalizations are made upon few studied species. Therefore, investigations dealing with the oogenesis and embryogenesis of more species are still necessary. Sycettusa hastifera is an alien species in the southwestern Atlantic. Knowledge about its reproduction would not only help to improve our comprehension of reproduction in Calcaronea but would also help to understand the capacity of this exotic species to colonize. Histological and electron microscopy analyses of individuals sampled at Arraial do Cabo (Rio de Janeiro, Brazil) showed that oogenesis in S. hastifera was long (4–6 months) and nutrients were acquired by association with nurse cells and endocytosis of bacteria, yielding heterogeneous and complex yolk inclusions. Cleavage, inversion, and amphiblastula larvae were similar to what has been observed in other calcaroneans, except for the larval cavity lacking amoeboid cells and the relatively long swimming period of the amphiblastula (on average 12 h, but reaching 72 h). Our results indicate that the vitellogenic mechanism characterized as mixed (an ancestral characteristic of Calcaronea) is strongly influenced by autosynthesis; during cleavage, cell fates could be determined from embryo to larva; and inversion of the embryo (which will become the amphiblastula larva) directly into the choanocyte chamber is an ancestral characteristic of Calcaronea. Despite the absence of amoeboid cells or other structures to nourish the larva, the long swimming period suggests that vitellogenesis is sufficient for the maintenance of the embryo and larva until metamorphosis. This characteristic may facilitate the spread of this cryptogenic species to new regions.

Terrestrialization in gastropods: lineages, ecological constraints and comparisons with other animals

Abstract Evolutionary transitions from water to land are infrequent. The physical contrasts between these media are amplified by biological differences in the patterns of selection. A new compilation, based on published phylogenetic and fossil evidence, identifies 30 separate instances of terrestrial colonization by gastropods, at least 12 from the sea and 14 from freshwater. Pre-Cenozoic transitions, mainly from freshwater and all tropical, resulted in high terrestrial diversity. Most Cenozoic colonizations were local, especially on oceanic islands, and yielded few terrestrial species. An increasingly predator-rich terrestrial environment after the Cretaceous made colonization on land unlikely except in cryptic habitats and on islands. Colonization from the sea became possible only in the Cenozoic, when marine lineages became specialized for life on the upper seashore. The results are compared with terrestrial colonizations by other groups of plants and animals.

Microbial mutualism suppression by Trichoderma and Bacillus species for controlling the invasive ambrosia beetle Xylosandrus compactus

Xylosandrus compactus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae) is among the most invasive ambrosia beetles causing severe damage to host plants belonging to various ecosystems. Foundress females excavate galleries into the plant xylem introducing mutualistic ambrosia fungi which are the exclusive food source for their offspring. The cryptic habits of this fungus-farming insect and its wide host range facilitated its rapid spreading worldwide. Despite several advances in deepening the bio-ecology of this beetle, there is still a general lack of information about effective control strategies. In this context, microbials, such as antagonistic bacteria and mycoparasitic fungi, can have the potential to act as alternative management tools. Here, we evaluated, for the first time, the potential of commercially available microbial agents for suppressing the growth of the main beetle mutualist, Ambrosiella xylebori, and consequently to hamper the beetle progeny development. The antagonistic activity of five Trichoderma and two Bacillus-based biofungicides was first evaluated in vitro by means of dual-culture experiments in Petri dishes. Then, beetle bioassays were conducted by exposing carob twigs, previously treated with different concentrations of each biofungicide, to beetle foundresses. Tested microbial antagonists significantly suppressed the growth of A. xylebori on Petri dishes. A significant reduction of the beetle progeny was observed in galleries of treated twigs compared to controls. The higher reduction in mutualist growth and brood production was obtained within galleries of T. atroviride treated twigs. Our results show the potential of the tested microbials to suppress the beetle mutualist growth within galleries and consequently to affect the development of its progeny.

Performance of innovative materials as recruitment substrates for coral restoration

Artificial reefs and, more recently, ecoengineering are frequently advocated as possible tools to counteract the loss of tropical coral reefs worldwide. Despite increasing availability of novel materials, there is limited understanding of how different materials and their physical and chemical properties can influence coral recruitment success and early benthic community development. This study investigated the efficacy of several innovative materials as recruitment substrates for corals and other sessile benthic communities. Stacks of vertically oriented tiles made of eight innovative materials and two common (control) materials were deployed for 6 months during major coral spawning events on the forereef of Mo'orea, French Polynesia. Tiles were separated from their neighbors by 15 mm to mimic cryptic habitats that are sheltered from predation and typically favored by coral recruits. Six innovative materials, including 3D printed concrete, polyvinyl chloride (PVC) with chitosan coating, fiberglass polymer, and flax‐based polylactic acid, produced similar coral recruitment to control materials (Portland concrete and PVC). Two materials (porous concrete and ceramic foam) produced lower recruitment. Porous concrete was characterized by a high abundance of non‐coralline encrusting red algae, which negatively correlated with coral recruitment, while ceramic foam was prone to erosion. The results suggest the structural micro‐complexity and durability of an artificial material and the composition of the benthic communities colonizing it can strongly influence coral recruitment. This study highlights several innovative materials as suitable recruitment substrates for coral restoration and provides a better understanding of the properties of artificial materials that are critical for coral recruitment success.