Natural Substrata Research Articles

A domesticated photoautotrophic microbial community as a biofilm model system for analyzing the influence of plastic surfaces on invertebrate grazers in limnic environments.

The environmental fate of plastic particles in water bodies is influenced by microbial biofilm formation. Invertebrate grazers may be affected when foraging biofilms on plastics compared to biofilms on natural substrata but the mechanistic basis for these effects is unknown. For analyzing these effects in ecotoxicological assays stable and reproducible biofilm communities are required that are related to the environmental site of interest. Here, a defined biofilm community was established and used to perform grazing experiments with a freshwater snail. For this, snippets of different plastic materials were incubated in the photic zone of three different freshwater sites. Amplicon sequencing of biofilms formed on these snippets showed that the site of incubation and not the plastic material dominated the microbial community composition. From these biofilms, individual microbial strains as well as photoautotrophic consortia were isolated; these consortia consisted of heterotrophic bacteria that were apparently nourished by microalga. While biofilms formed by defined dual cultures of a microalga and an Alphaproteobacterium were not accepted by the snail P. fontinalis, a photoautotrophic consortium (Co_3) sustained growth and metabolism of this grazer. Amplicon sequencing revealed that consortium Co_3, which could be stably maintained on solid medium under photoautotrophic conditions, reproducibly formed biofilms of a defined composition on three different plastic materials and on glass surfaces. In conclusion, our study shows that the generation of domesticated photoautotrophic microbial communities is a valid novel approach for establishing laboratory ecotoxicological assays with higher environmental relevance than those based on defined microbiota.

Underwater macrophotogrammetry to monitor in situ benthic communities at submillimetre scale

Abstract Larval settlement and recruitment of sessile organisms are key ecological processes for population recovery and maintenance that occur at scales invisible to the human eye. Accordingly, proxies of recruitment have commonly been quantified using artificial substrata such as settlement tiles made of diverse materials and shapes, which are typically transported to the laboratory for examination. However, it is unknown how much bias is introduced with this sampling strategy and how recruitment quantified on tiles relates to recruitment on nearby natural substrata. Here, we applied techniques that combine macrophotography with photogrammetry (macrophotogrammetry) underwater to monitor benthic communities at submillimetre scale. This application allows the investigation of recruitment and community succession of the earliest life‐history stages in situ and on natural substrata. We tested the use of four different imaging systems, varying in costs from US$ 1400 to US$ 5440. While the most expensive SONY αRiv system provided the best visual output and ground resolution (up to 5 μm/pixel with a + 4 close‐up lens); regardless of systems, 3D models always had a ground resolution ≤23 μm/pixel and errors in planar measurements of submillimetre features were similar among systems. This level of resolution compares well with stereomicroscopy in the range of 5:1 to 10:1 magnification, while providing detailed 3D digital records through time. Using a coral reef example, we apply this approach to demonstrate how it can be used to monitor small reef areas (~300–600 cm2) through time, including the quantification of biophysical metrics such as cover of small facilitative and competitive organisms and microhabitat complexity. We further show that organisms as small 0.5 mm in size, such as 2‐month‐old coral settlers, can be located accurately within the 3D models and measured with a good level of confidence. This method can be readily applied to other benthic environments to elucidate drivers of early recruitment and recovery of benthic organisms following disturbance impacts at very fine scales, directly on natural substrata, to avoid biases inherent with laboratory‐based analyses of artificial surfaces.

Assessment of the macroalgal diversity of Kuwait by using the Germling Emergence Method

Cryptic stages of diverse macroalgae present in natural substrata, “the bank of microscopic forms”, were isolated into clonal cultures and identified based on both morphological characteristics and DNA barcoding. Approximately 120 clonal isolates from 308 natural substratum samples were collected from the entire coastline of Kuwait. Amongst these isolates, 77 (64%) were identified through DNA barcoding using the nuclear ribosomal small subunit, RuBisCO spacer (ITS2, <i>tufa</i>, <i>rbc</i>L, <i>psa</i>A, and <i>psb</i>A) and sequencing. Twenty-six isolates (34%) were identified in the division Chlorophyta, 18 (23%) as Phaeophyceae, and 33 (43%) as Rhodophyta. For all DNA sequences in this study, species-level cut off applied was ≥98% homology which depend entirely on the markers used. Three putative new records of Chlorophyta new for the Arabian Gulf were made: <i>Cladophora laetevirens</i> (Dillwyn) Kützing, <i>Ulva torta</i> (Mertens) Trevisan and <i>Ulvella leptochaete</i> (Huber) R. Nielsen, C. J. O′Kelly & B. Wysor in Nielsen, while <i>Cladophora gracilis</i> Kützing and <i>Ulva ohnoi</i> M. Hiraoka & <i>S. Shimada</i> are new records for Kuwait. For Phaeophyceae, Ectocarpus subulatus Kützing and <i>Elachista stellaris</i> Areschoug were new records for the Gulf and Kuwait. In the Rhodophyta, <i>Acrochaetium secundatum</i> (Lyngbye) Nägeli in Nägeli & Cramer, <i>Ceramium affine</i> Setchell & N. L. Gardner, <i>Gelidium pusillum</i> var. <i>pakistanicum</i> Afaq-Husain & Shameel and <i>Dasya caraibica</i> Børgesen are new records for the Gulf and Kuwait, while the red alga <i>Stylonema alsidii</i> (Zanardini) K. Drew is a new record for Kuwait. Several isolates identified corresponded to genera not previously reported in Kuwait and / or the Arabian Gulf, such as <i>Porphyrostromium</i> Trevisan, a new genus from the Bangiales, and two unidentified species for the Planophilaceae Škaloud & Leliaert. The isolates cultivated from substrata enhance understanding of the marine macroalgal diversity in the region and confirmed that the Germling Emergence Method is suitable for determining the actual diversity of a given study area through isolation from cryptic life-history phases.

Comparison of microbial colonization between natural and plastic substrata in a polluted watershed.

Plastic pollution represents a threat for biological communities and the ecological functions they provide in river ecosystems. In this study, we compared the microbial colonization of two plastics (biodegradable and non-biodegradable) and three natural substrata (leaves, sediment and rocks) in two study sites of an urbanized watershed differing in their plastic-contamination degree (upstream and downstream). The density and diversity of bacterial, fungal and algal communities, as well as the extracellular enzymatic activities β-glucosidase (GLU), N-acetyl-glucosaminidase (NAG) and phosphatase (PHO), were analyzed in each substrata and site over a four-week colonization experiment. Results showed higher microbial densities and enzymatic activities in leaves and sediment compared to plastics and rocks, probably due to the greater availability of organic carbon and nutrients in the former substrata. However, the microbial colonization of the two plastics was only different in the downstream site where bacterial density and enzymatic activities were higher in the biodegradable compared to the non-biodegradable plastic. Accordingly, the presence of biodegradable plastics would enhance the heterotrophic metabolism in plastic-polluted rivers.

Active restoration efforts in the Central Mexican Pacific as a strategy for coral reef recovery

Introduction: The 1997-98 El Niño event caused massive coral bleaching and mortality in the Central Mexican Pacific (CMP). Punta de Mita alone used to harbor more than 30 % of the coral coverage in this region, with a mono-specific Pocillopora coverage. The 1997-1998 ENSO event caused massive coral mortality reducing live coral coverage to < 5 %. Despite being considered a coral region unlikely to recover, recent restoration efforts have been implemented to rehabilitate the coral community.
 Objective: To assess coral recovery by analyzing the coral growth and survival rates of branching Pocillopora species at Punta de Mita.
 Methods: Healthy coral fragments of opportunity were re-attached to the natural substrata using zip ties and measured considering their growth in terms of maximum length and width (cm) to determine their annual extension rates.
 Results: After 50 weeks, corals duplicated their size, with a mean growth of ~ 4 cm year-1. After 100 weeks (2 years), corals triplicated their size, increasing on average 8–9 cm in each diameter.
 Conclusions: Successful coral reef restoration activities in the Central Mexican Pacific are the result of Pocillopora’s physiological processes, such as fast growth rates, and recent life-history traits, like the ability to cope with thermal anomalies, which enable them to thrive in a dynamic region severely affected by natural and anthropogenic perturbations. Indeed, a region considered unlikely to recover has regained its live coral cover from < 5 % in 1998 up to 15 % in 20 years. This demonstrates the importance of assisting natural coral recovery with restoration efforts, especially in coral locations that, despite environmental perturbations, have proven to be resilient and may become coral refugia areas under the current climate change scenario.

Using standardized fish‐specific autonomous reef monitoring structures (FARMS) to quantify cryptobenthic fish communities

Abstract Biodiversity inventories and monitoring techniques for marine fishes often overlook small (<5 cm), bottom‐associated (‘cryptobenthic’) fishes, and few standardized, comparative assessments of cryptobenthic fish communities exist. We sought to develop a standardized, quantitative survey method for cryptobenthic fishes that permits their sampling across a variety of habitats and conditions. Fish‐specific autonomous reef monitoring structures (FARMS) are designed to sample cryptobenthic fishes using a suite of accessible and affordable materials. To generate a variety of microhabitats, FARMS consist of three layers of stacked PVC pipes in three different sizes, as well as a bottom and top level of loose PVC‐pipe fragments in a mesh basket. We deployed FARMS across a variety of habitats, including coral reefs, seagrass beds, oyster reefs, mangroves, and soft‐bottom habitats across six locations (Hawai'i, Texas, Panama, Saudi Arabia, Brazil, and Curaçao). From shallow estuaries to coral reefs beyond 100 m depth, FARMS attracted distinct communities of native cryptobenthic fishes with strong site or habitat specificity. Comparing the FARMS to communities sampled with alternative methods (enclosed clove‐oil stations on coral reefs in Panama and oyster sampling units on oyster reefs in Texas) suggests that FARMS yield a subset of cryptobenthic fish species that are representative of those present on local coral and oyster reefs. While FARMS yield fewer individuals per sample, they are efficient sampling devices relative to the sampled area. We demonstrate that FARMS represent a useful tool for standardized collections of cryptobenthic fishes. While natural substrata are bound to yield more mature communities with a larger number of individuals and wider range of specialist species, the potential to deploy and retrieve FARMS in turbid environments, beyond regular SCUBA depth, and where fish collections using anaesthetics or ichthyocides are forbidden suggests that they are a valuable complementary technique to survey fishes in aquatic ecosystems. Deploying FARMS in locations and habitats where cryptobenthic fish communities have not been studied in detail may yield many valuable specimens of unknown or poorly known species.

Genotyping of two congeneric bitterling fish species by nuclear SNP markers and the detection of hybridization in a sympatric region

AbstractBitterling fish species (subfamily: Acheilognathinae) are endangered in Japan due to habitat loss. The decline of freshwater mussels also enhances the decrease of bitterlings because bitterlings lay eggs in the gills of freshwater mussels. Furthermore, loss of unionid mussels causes hybridization between bitterling species. This study aims to analyze the frequency of hybridization between congeneric species of bitterlings—Tanakia lanceolata and Tanakia limbata—at a well‐preserved site, where both species occur naturally and compare this with other regions more severely impacted by human intervention. One part of the irrigation streams of the Asahi River System, Okayama, is inhabited by a natural monument species of Japan, a benthic cobitid, Parabotia curtus, and therefore, the natural substratum and the structurally heterogeneous stream banks are maintained. We collected Tanakia individuals and surveyed mussel density at this well‐preserved site. We also developed six nuclear single‐nucleotide polymorphism (SNP) markers on different chromosomes to distinguish T. lanceolata and T. limbata. These SNP markers effectively determined individuals as being either one of these species or a hybrid. Based on genotyping, eight individuals were determined to be hybrids, whereas 90 and 173 individuals were determined as purebreds of T. lanceolata and T. limbata, respectively. The proportion of hybrid individuals was 3.0% and was relatively low compared to other regions. In addition, five species of unionids were densely distributed in this stream. Prezygotic isolation between sympatric T. lanceolata and T. limbata was established at this well‐preserved site, where unionid mussels are densely populated and provide enough breeding substrate for both species.

Dual-Approach Electrochemical Surface-Enhanced Raman Scattering Detection of Mycobacterium tuberculosis in Patient-Derived Biological Specimens: Proof of Concept for a Generalizable Method to Detect and Identify Bacterial Pathogens.

The recent surge in infectious disease-causing pathogens, resulting in global catastrophe, has merited a pivotal quest toward point-of-care (POC) diagnostics. Mycobacterium tuberculosis (MTB) is still the top bacterium-based infectious disease-causing pathogen worldwide. In a concerted effort toward simplifying and decentralizing the discriminatory screening of MTB causing pathogens, electrochemical surface-enhanced Raman scattering (EC-SERS) was adopted to create a customized screening tool. The development strategy combined five key factors, including (i) a simplified Tollens'-based chemical synthesis method for bulk supply of silver nanoparticles, (ii) the deliberate surface modification of nanoparticles with carefully selected polyelectrolytes to resemble the conditioning layer usually found on a natural substratum, (iii) uniform SERS-active films formed through simple unprogrammed assembly, (iv) the controlled manipulation of the local electric field through applied voltage using a technique that does not conform to the limitations of classical EC-SERS, and (v) the inherent specificity of the target-specific SERS vibrational signature. The EC-SERS platform was able to discriminatively detect and identify TB-derived mycobacteria, including three clinically relevant MTB strains, TB-H37Rv, TB-HN878, and TB-CDC1551. Moreover, a customized voltage stepping protocol, compatible with either the inclusion of a short preincubation step or with in situ EC-SERS is illustrated. From the obtained SERS vibrational signatures, a band indicating a mode unique to TB-derived/TB-affiliated mycobacteria and thus not observed for other bacterial types used in this study was illustrated. Furthermore, provisional investigation, done as prelude for assessing the potential for translational adaptability of the EC-SERS technique toward POC clinical settings for sputum and urine specimens, was carried out.

The travelling particles: community dynamics of biofilms on microplastics transferred along a salinity gradient

Microplastics (MP), as novel substrata for microbial colonization within aquatic ecosystems, are a matter of growing concern due to their potential to propagate foreign or invasive species across different environments. MP are known to harbour a diversity of microorganisms, yet little is understood of the dynamics of their biofilms and their capacity to successfully displace these microorganisms across different aquatic ecosystems typically marked by steep salinity gradients. To address this, we performed an in situ sequential incubation experiment to simulate MP transport from riverine to coastal seawaters using synthetic (high-density polyethylene, HDPE and tyre wear, TW) and natural (Wood) substrata. Bacterial communities on incubated particles were compared to each other as well as to those in surrounding waters, and their dynamics along the gradient investigated. All communities differed significantly from each other in their overall structure along the salinity gradient and were shaped by different ecological processes. While HDPE communities were governed by environmental selection, those on TW and Wood were dominated by stochastic events of dispersal and drift. Upon transfer into coastal seawaters, an almost complete turnover was observed among HDPE and TW communities. While synthetic particles displaced a minor proportion of communities across the salinity gradient, some of these comprised putatively pathogenic and resistant taxa. Our findings present an extensive assessment of MP biofilms and their dynamics upon displacement across different aquatic systems, presenting new insights into the role of MP as transport vectors.

Sorption of selected pharmaceuticals on river benthic biofilms formed on artificial substrata

The dissolved organic and inorganic contaminants in rivers, lakes and seas are distributed among the aquatic phase, biota, sediments and biofilms formed on different artificial and natural substrata. Since the biofilms play an important role in the food web of aquatic ecosystems, it is necessary to clarify what kind of contaminants are bounded to these biological surfaces. In this study the concentration of eight pharmaceuticals (carbamazepine, ciprofloxacin, clarithromycin, diclofenac, metoprolol, sitagliptin, sulfamethoxazole and tetracycline) was determined in the Danube water at Budapest (Hungary) and in the biofilms formed on glass and polycarbonate substrata during a six weeks long growing period at the same sampling site. The target compounds were extracted from the dried biofilms by microwave (MW) assisted hot water treatment, however, the recovery of tetracycline was extremely low, indicating damage and loss of this constituent caused by MW treatment. The concentrations of the other seven pharmaceuticals were determined by LC-MS following the solid phase extraction of analytes. Clarithromycin, ciprofloxacin, diclofenac, metoprolol and sitagliptin were detectable in the biofilms due to biological uptake and electrostatic-mediated adsorption on the negatively charged biofilms, however, carbamazepine and sulfamethoxazole with neutral charge were not detected. The bioaccumulation factors of biofilms grown on glass or polycarbonate substrata changed between 175 and 614 and 148–314 L/kg, respectively, and increased in order of diclofenac < sitagliptin < clarithromycin < ciprofloxacin < metoprolol. These values are about 2–3 orders of magnitude lower than the published data for different metal cations which form chemical complexes or chelates with carboxyl and hydroxyl groups of extracellular polymer matrix. Due to the higher amount of adsorbed pharmaceuticals and the higher biodiversity of diatom species in the biofilms formed on glass substrata, compared to polycarbonate, as artificial substrata the glass carrier plates can be recommended for biofilm studies.

Hyporheic exchange due to in-stream geomorphic structures

In-stream structures, such as channel spanning logs and weirs, can enhance hyporheic exchange in streams. Hyporheic exchange is important for stream ecosystem function, and restoring this function is a goal of many stream restoration projects. However, studies on the connection between in-stream structure size, hydrogeologic setting, and hyporheic exchange remain inadequately characterized. In this study, we combined flume experiments and numerical simulations to systematically evaluate how in-stream structure and its hydrogeologic setting impacted the hyporheic vertical exchange flux, Q, the solute penetration depth, Dp, and the solute flux, QS, in the hyporheic zone. The results showed that stream water downwells into the riverbed upstream of the weir and upwells downstream. Exchange rates were greatest near the weir and decay with distance upstream and downstream. Model results indicated Q, Dp and QS had a positive exponential relationship with the weir height, h, the flow velocity, u, and the sediment intrinsic permeability, k. While model results indicated that u was the most important factor determining Q, Dp and QS, followed by h, while only h reached a certain value, the hyporheic exchange would increase with the height and vice versa. Hyporheic exchange generally was sensitive to changes in k, only the magnitude of k varied from 10−8–10−10m2. This finding suggests that a rethinking of the currently applied restoration techniques is required to better consider in-stream structure size, hydrological conditions and natural substratum dynamics in river restoration.

Removal of macroalgae from degraded reefs enhances coral recruitment

Declining coral cover on tropical coral reefs often results in a concomitant increase in macroalgae. When proliferation of macroalgae persists outside regular seasonal growth, it can shift the ecosystem dominance away from corals into a permanently altered system. Such an altered system is unlikely to recover naturally, despite ample supply of coral larvae, as coral settlement and survival is reduced by the presence of macroalgae. Physical removal of macroalgae has been proposed to overcome this biotic barrier to recovery, although empirical evidence demonstrating the effects of removal on phase‐shifted reefs is lacking. Here, we manually removed macroalgae from twelve 25 m2 experimental plots (88.5 ± 6.2 kg wet weight per plot; 90% benthic cover decrease) on a degraded reef prior to coral mass spawning across 2 years and recorded the number of coral recruits to settlement tiles and natural substrata. Four months after each spawning event, we found a threefold increase in coral recruits to tiles in plots where macroalgae had been removed (n = 12 plots; February 2019: mean 45.9 ± 12.7 recruits per tile; February 2020: mean 53.9 ± 5.9 recruits per tile) compared to control plots where macroalgae remained (n = 12 plots; February 2019 mean: 13.6 ± 2.8 recruits per tile; February 2020 mean: 17.5 ± 3.5 recruits per tile). These results suggest that, at small scales, macroalgae removal may be a useful intervention to boost recruitment on degraded reefs. Longer‐term monitoring is needed to document if coral survivorship, growth, and subsequent reef recovery occurs.

DNA barcoding of marine algae from Malta: new records from the central Mediterranean

The heterokont benthic multicellular algae Schizocladia ischiensis E.C. Henry, K. Okuda et H. Kawai (Schizocladiophyceae), Hecatonema terminale (Kützing) Kylin and Striaria attenuata (Greville) Greville (Phaeophyceae) are reported for the first time from the waters around the Maltese islands in the central Mediterranean. They were identified through algal isolation from incubated natural substrata, coupled with DNA barcoding targeting the biomarkers COI and rbcL plus the RuBisCO spacer. For three additional brown algae, Colpomenia sinuosa (Mertens ex Roth) Derbès et Solier, Asperococcus bullosus J.V.Lamouroux and Sphacelaria sp., DNA sequences confirmed previous morphology-based records from Malta. This paper also provides an updated literature-based species list of the marine macroalgae present in Malta.

Occurrence and Habitat Characteristics of Aurelia sp. Polyps in a High-Latitude Fjord

Causes and consequences of jellyfish bloom formation are subject to controversial discussions worldwide. While medusae have been studied to a broader extent, the knowledge on polyp stages of scyphozoans is limited thus hampering reliable prediction of jellyfish bloom formation. This study describes the occurrence, abundance, habitat characteristics and interactions of scyphozoan Aurelia sp. polyp colonies with other fouling organisms in intertidal and subtidal sectors of Trondheimsfjorden (Norway). In total, 982 polyps were found on 70 substrata of varying material types during a field survey in spring-summer 2018 along a longitudinal gradient within and outside Trondheimsfjorden. The polyps were identified as Aurelia sp. based on molecular species identification. Most polyps were found in bays with macroalgae canopy on the down facing side of artificial and natural substrata (rocks, concrete, iron) and inside rock cracks. Polyp microhabitats included the surface of Ascidia mentula (solitary ascidian), increments of Pomatoceros triqueter (polychete) tubes and dead Balanus balanoides (barnacle) shells. Based on the deployment of settling plates, abundance of Aurelia sp. polyps ranged from 1.2 (± 0.7) to 0.12 (± 0.07) polyps cm–2. Settlement occurred either directly on the PVC settling plates or as epibionts on the ascidian Ascidia mentula and on barnacle shells of Balanus balanoides. This study provides insights into the potential of local Aurelia sp. polyps contributing to the seasonal occurrence and abundance of Aurelia sp. in fjord systems, where intensive blooms occur annually.

Disentangling the impact of artificial substrata on the trophic ecology of the highly endangered marine invertebrate Patella ferruginea Gmelin, 1791

ABSTRACT Limpets are keystone species worldwide, promoting marine biodiversity in coastal areas. Of special concern are the so-called giant limpets such as Patella ferruginea, either due to their role in marine ecosystems and/or threatened status. The proliferation of artificial substrata caused by human population growth has allowed their use as a surrogate habitat for many species of limpets. However, little is known about the impact on the trophic ecology of these species caused by artificial substrata. The stable isotope approach has been widely used to explore the trophic ecology of marine species and so was used in the present study of P. ferruginea. The results of this study indicated that diet consumption differs between artificial and natural substrata for P. ferruginea. Enrichment in δ15N values of specimens collected within the harbour of Ceuta indicates that this endangered species would be a useful indicator for detecting anthropogenically derived organic matter in coastal areas. Further research is required to evaluate the impact of artificial substrata from a conservational perspective.

Diversity of estuarine and marine hydroids (Cnidaria, Hydrozoa) from subtropical ecosystems of Brazil

The subtropical coastal waters of Brazil have been surveyed regarding their hydroid fauna since 1941. However, a comprehensive compilation of all hydroid records with detailed information has not yet been published for these waters. Besides filling this knowledge gap, we provide an updated species list, along with the biogeographic status (native, introduced, or cryptogenic) of each hydroid species for the area between Ilha Comprida municipality and the state of Rio Grande do Sul. We also present the distribution patterns of hydroid morphotypes, a sampling sufficiency analysis, and spatial-temporal progress of their research. The dataset was compiled by conducting a thorough bibliographical survey, accessing data of zoological collections, and performing field surveys with experimental settlement panels. This work provides an update for new hydroid records for a large number of localities within the study area. We listed 27 families, 59 genera, 129 morphotypes, and 95 unique species. Regarding the unique species, ~ 3% were classified as introduced, ~ 2% as native, and ~ 95% as cryptogenic. The 3% of introduced species include the first record of the non-indigenous Podocoryna loyola on natural substrata and new records of this species for Sao Paulo. The 95 unique species also represent ~ 19% and ~ 52% of the hydroid fauna recorded in South America and Brazil, respectively. Sampling effort is still not sufficient and therefore continuing research on the hydroid fauna is required, especially for the detection of new introduced species.

On some Smittinidae (Bryozoa, Cheilostomata) from Bahia, northeastern Brazil, with the description of a new species

Here, we present the taxonomy of five little-known cheilostome smittinid species of Bahia State, northeast Brazil, assigned to Hemismittoidea Soule & Soule, 1973, Smittina Norman, 1903, and Smittoidea Osburn, 1952. Specimens of four species previously reported in the studied area were reassessed: Hemismittoidea asymmetrica Ramalho et al., 2018, Smittina affinis (Hincks, 1862), Smittoidea evelinae (Marcus, 1937), and Smittoidea reticulata (MacGillivray, 1842). Hemismittoidea asymmetrica here is considered a junior synonym of Hemismittoidea corallinea Soule & Soule, 1973. The last three species here are assigned to Smittina smittiella Osburn, 1947, Smittoidea numma (Marcus, 1949) comb. nov., and Smittoidea complexa sp. nov., respectively. An additional species, Smittoidea pacifica Soule & Soule, 1973, is recorded for the first time in Brazil. Diagnostic characters of Smittinidae genera and species are discussed, and new combinations are proposed. Most of the taxa reported here were collected from natural substrata, mainly from coral reefs and rhodoliths, and also from artificial structures such as experimental plates, which can provide evidence regarding the passive dispersal ability of these animals (e.g., as hull fouling) and their potential for bioinvasion along the Brazilian coast.

Heliocephala variabilis and Pseudopenidiella vietnamensis: Two New Hyphomycetous Species in the Microthyriaceae (Dothideomycetes) from Vietnam.

In a survey of microfungi from plant debris collected in Vietnam, two new hyphomycetous species were found, which belong to the genera Heliocephala and Pseudopenidiella and the family Microthyriaceae (Microthyriales, Dothideomycetes). Maximum Likelihood and Bayesian Inference sequence analyses of the internal transcribed spacers (ITS) and large subunit (LSU) of the ribosomal DNA barcodes allowed assessing the phylogenetic relationships of the new species with other species of the respective genera. Heliocephala variabilis sp. nov. was closely related to Heliocephala elegans, Heliocephala gracilis, and Heliocephala zimbabweensis, from which it was morphologically distinguished by its smaller conidiophores and non-rostrate conidia of up to four septa on the natural substratum. Pseudopenidiella vietnamensis sp. nov. was related to Pseudopenidiella piceae and Pseudopenidiella podocarpi and differed from the former principally by its lack of microcondiophores and from P. podocarpi by having larger macroconidiophores and smooth conidia. Key morphological features to distinguish the accepted species in Heliocephala and Pseudopenidiella are also provided. In addition, Pseudopenidiella pini was excluded from the genus on the basis of its morphological features.

Lichen Colonization on Unusual Man-Made Substratum in Western Himalaya

The lichens along with their natural substratum colonize a variety of man-made substratum. After about half a century of lichenological research in India, there has been no record of lichen colonization on the man-made artificial substratum. The authors here for the first time report colonization of five species of lichens on three samples from two unusual habitats—iron railway sleepers—Heterodermia galactophylla (Tuck.) W.L. Culb. and abandoned woolen socks—Xanthoparmelia bellatula (Kurok. & Filson) Elix & J. Johnst., Physcia gomukhensis D.D. Awasthi & S.R. Singh, Xanthoparmelia congensis (J. Steiner) Hale and Xanthoria candelaria (L.) Th. Fr. in western Himalaya. Two supplementary tables (S1 and S2) are provided, giving details of collection sites and lichen species identified in each sample. The study revealed the extended geographical distribution of the two lichen species, i.e., Heterodermia galactophylla (Tuck.) W.L. Culb and Physcia gomukhensis D.D. Awasthi & S.R. Singh, highlighting the importance of such studies of unusual habitats in lichen diversity and preparation of their inventories.

A Preliminary inventory of alien and cryptogenic species in Monastir Bay, Tunisia: spatial distribution, introduction trends and pathways

The Mediterranean Sea is a marine biodiversity hotspot under threat. One of the major impacts on its biological resources and services comes from the invasiveness of non-indigenous species (NIS). Nevertheless, NIS monitoring programs in the south basin of the Mediterranean Sea are in an early implementation stage. This study aims to describe NIS and cryptogenic species distribution in Monastir Bay (Tunisia) and to identify risk areas for the introduction and spread of invasive species, providing a baseline for future monitoring programs. To this end, a series of Rapid Assessment Surveys were carried out to identify NIS and cryptogenic species in one marina, five fishing ports, two aquaculture farms and the Special Conservation Area of the Kuriat islands. 24 species were found, of which 11 constitute new records for Monastir Bay, which represent a 33.3% of the total NIS reported in this Bay. Assemblages differed between substrata types, being NIS more abundant in artificial than in natural substrata. Regarding locations, Cap Monastir Marina was the most invaded site, the most transited by vessels and the only one visited by international sailing. Hence, this marina constitutes the main risk area to be monitored, although the fishing ports and fishing farms in the semi-enclosed coastal lagoon of Monastir Bay can also be considered as risk areas. Nevertheless, more research effort is needed in Monastir Bay in order to update the records of NIS and cryptogenic species and increase insight on the ecological evolution of these species and their related impacts on natural communities and marine resources.