Marina Species Research Articles

Is the invasive Caprella scaura Templeton, 1836 displacing its resident congener Caprella equilibra Say, 1818 in marinas of the South Iberian Peninsula? A long-term spatio-temporal approach

Although marine invasions are increasingly a matter of concern, the impact of invasive species in the ecosystem and their ability to replace native taxa is still little understood. Data from 2011 to 2021 in marinas of the Southern Iberian Peninsula supported that the invasive amphipod Caprella scaura is replacing the resident Caprella equilibra over time. Six marinas where C. equilibra was abundant in 2011 and C. scaura was absent, are now dominated by C. scaura. Although this displacement is more evident in Mediterranean shores than in Atlantic coasts, it is very variable between marinas. The spreading of the invasive species in marinas of the Alboran Sea mainly occurred from 2011 to 2017, preventing C. equilibra from regaining its former distribution. The ultimate factors responsible for the displacement, such as the aggressive behaviour of C. scaura, environmental influences or physiological performance in a global warming context, should be further investigated experimentally.

Temperature-driven dynamics: unraveling the impact of climate change on cryptic species interactions within the Litoditis marina complex.

Anthropogenic climate change and the associated increase in sea temperatures are projected to greatly impact marine ecosystems. Temperature variation can influence the interactions between species, leading to cascading effects on the abundance, diversity and composition of communities. Such changes in community structure can have consequences on ecosystem stability, processes and the services it provides. Therefore, it is important to better understand the role of species interactions in the development of communities and how they are influenced by environmental factors like temperature. The coexistence of closely related cryptic species, with significant biological and ecological differences, makes this even more complex. This study investigated the effect of temperature on species growth and both intra- and interspecific interactions of three species within the free-living nematode Litoditis marina complex. To achieve this, closed microcosm experiments were conducted on the L. marina species Pm I, Pm III and Pm IV in monoculture and combined cultures at two temperature treatments of 15 °C and 20 °C. A population model was constructed to elucidate and quantify the effects of intra- and interspecific interactions on nematode populations. The relative competitive abilities of the investigated species were quantified using the Modern Coexistence Theory (MCT) framework. Temperature had strong and disparate effects on the population growth of the distinct L. marina species. This indicates temperature could play an important role in the distribution of these cryptic species. Both competitive and facilitative interactions were observed in the experiments. Temperature affected both the type and the strength of the species interactions, suggesting a change in temperature could impact the coexistence of these closely related species, alter community dynamics and consequently affect ecosystem processes and services.

LPS-Dephosphorylating Cobetia amphilecti Alkaline Phosphatase of PhoA Family Divergent from the Multiple Homologues of Cobetia spp.

A highly active alkaline phosphatase (ALP) of the protein structural family PhoA, from a mussel gut-associated strain of the marine bacterium Cobetia amphilecti KMM 296 (CmAP), was found to effectively dephosphorylate lipopolysaccharides (LPS). Therefore, the aim of this work was to perform a comprehensive bioinformatics analysis of the structure, and to suggest the physiological role of this enzyme in marine bacteria of the genus Cobetia. A scrutiny of the CmAP-like sequences in 36 available Cobetia genomes revealed nine homologues intrinsic to the subspecies C. amphilecti, whereas PhoA of a distant relative Cobetia crustatorum JO1T carried an inactive mutation. However, phylogenetic analysis of all available Cobetia ALP sequences showed that each strain of the genus Cobetia possesses several ALP variants, mostly the genes encoding for PhoD and PhoX families. The C. amphilecti strains have a complete set of four ALP families' genes, namely: PhoA, PafA, PhoX, and two PhoD structures. The Cobetia marina species is distinguished by the presence of only three PhoX and PhoD genes. The Cobetia PhoA proteins are clustered together with the human and squid LPS-detoxifying enzymes. In addition, the predicted PhoA biosynthesis gene cluster suggests its involvement in the control of cellular redox balance, homeostasis, and cell cycle. Apparently, the variety of ALPs in Cobetia spp. indicates significant adaptability to phosphorus-replete and depleted environments and a notable organophosphate destructor in eco-niches from which they once emerged, including Zostera spp. The ALP clusterization and degree of similarity of the genus-specific biosynthetic genes encoding for ectoine and polyketide cluster T1PKS, responsible for sulfated extracellular polysaccharide synthesis, coincide with a new whole genome-based taxonomic classification of the genus Cobetia. The Cobetia strains and their ALPs are suggested to be adaptable for use in agriculture, biotechnology and biomedicine.

Cryptic diversity in toads of the Rhinella marina species group (Anura, Bufonidae) with a subjectively beautiful new species from Western Ecuador

Abstract The mainly Mesoamerican cane toad, Rhinella horribilis, is the northernmost species in the Rhinella marina species group of giant or cane toads, occupying an extensive range west of the Andean Cordillera from Ecuador north to southern Texas. However, a thorough assessment of geographic variation among R. horribilis populations, and of the phylogenetic relationships of the R. marina species complex, indicates previously unsuspected diversity within this species as currently recognized. Specifically, we evaluated whether toad populations from western Ecuador represent an evolutionary lineage distinct from the rest of R. horribilis based on extensive specimen collections and the combined evidence of mtDNA sequence variation, morphological, bioacoustics, and environmental information. Our results revealed that populations west of the Ecuadorian Andes constitute a well-supported, monophyletic clade that is distinctly different genetically, morphologically, acoustically, and ecologically from a sister taxon composed of R. horribilis populations from Central America and from populations ascribable to R. marina s.s. from the Amazon Basin of Ecuador and other countries. The weight of evidence confirms a new species (R. bella sp. nov.), described here, adding to our understanding of biogeographic relationships in this widespread clade of Neotropical toads. The new species name means ‘beautiful’ in Latin, in contrast to its sister species, ‘horribilis’. In addition, we designate a lectotype for Bufo marinus var. fluminensis to avoid ambiguity in the applicability of that name.

Community local awareness in respecting coastal land conservation in Cemara Labat Village of Central Kalimantan

Utilization of coastal land in the community of Cemara Labat Village has been passed down from generation to generation. The people of Cemara Labat Village still maintain the tradition of coastal land management, such as planting certain types of mangroves, prohibiting cutting down mangrove forests and hunting animals which are regulated in unwritten customary law or local wisdom. Utilization of coastal area resources by humans from time to time continues to increase. The intensity of exploiting the potential of coastal areas resources often does not pay attention to the carrying capacity and principles of optimal and sustainable use of natural resources. Therefore, the mangrove forest ecosystem in Cemara Labat Village needs to be preserved both ecologically and biologically with an awareness approach to local wisdom. The results showed that Avicennia marina species had a very high dominance (80%) in the mangrove forest area of Cemara Labat Village, for animal especially in the mangrove forest area, was bird dominant species (Aves), while the level of community participation in mangrove forest conservation was moderate (75%).

Kearifan Lokal Masyarakat Menyikapi Konservasi Lahan Pesisir Di Desa Cemara Labat

Utilization of coastal land in the community of Cemara Labat Village has been passed down from generation to generation. The people of Cemara Labat Village still maintain the tradition of coastal land management, such as planting certain types of mangroves, prohibiting cutting down mangrove forests and hunting animals which are regulated in unwritten customary law or local wisdom. Utilization of coastal area resources by humans from time to time continues to increase. The intensity of exploiting the potential of coastal areas resources often does not pay attention to the carrying capacity and principles of optimal and sustainable use of natural resources. Therefore, the mangrove forest ecosystem in Cemara Labat Village needs to be preserved both ecologically and biologically with an awareness approach to local wisdom. The data collection which used in this research was interview method, observation method, and survey. The results showed that Avicennia marina species had a very high dominance (80%) in the mangrove forest area of Cemara Labat Village, especially in the mangrove forest area, was bird species (Aves), while the level of community participation in mangrove forest conservation was moderate (76%). The strategy of developing community local wisdom on coastal land conservation in Cemara Labat village is in the Strengths-Opportunities or SO strategy, which is quadrant I which means Growth (6.40) or experiencing growth. Some alternative SO (strength opportunities) strategies include :a) Formulate regional policies on mangrove forest management, b) Promote the potential value of mangroves and their development opportunities, c) Improve the role and performance of stakeholders in mangrove forest management, d) Improve people's economy and empower coastal communities.

SYSTEMATIC STUDY OF CARBON SEQUESTRATION OF MANGROVE FORESTS AT RAIGAD DISTRICT COAST, MAHARASHTRA, INDIA

Mangrove forests are highly productive ecosystems with carbon sequestration rate almost equivalent to tropical green forests. Mangroves distribute proportionally more carbon below ground and possess higher below to above ground carbon mass ratio as compared to any other forests (Kathiresen, 2004). Mangrove is amongst the most carbon rich biomes containing more than 950 tC/H. The said study overlooks destructive and non-destructive methods of the carbon sequestration. It is conducted as a comparative assessment of the carbon sequestration potential of mangrove and non-mangrove regions. By means of methodology of calculating Soil Bulk Density (gcm -3) and Total Organic Carbon (TOC) in mangroves soils (El Wakeel and Riley, 1956) and Carbon Sequestration Rate (CSR) is estimated based on the sediment rates and TOC content of the soil (Duan Xiaonan et al (2008). The systematic assessment conducted at West Coast of Maharashtra; shows mangrove region with Avicinnia marina species and in non–mangrove region total carbon in soil (%) recorded 17.15% and 4.52 percent respectively. Total Soil Carbon Stock recorded is 431 million g / Ha at mangrove region and 105.7 million g / Ha at non mangrove region. After methodical estimation of biomass and carbon stock of mangroves (English et.al, 1997 and Kaufman and Donato, 2012), total carbon stock of mangrove stand was recorded 393.14 mg/Ha and that of non-mangrove stand was recorded to be 91.7 mg/Ha. It shows that mangroves absorb almost 315.14 percent more carbon than non-mangrove region. In other words, carbon stock in Avicinnia marina stand found to be almost 3 times more than non-mangrove zone.

Reforestation of grey mangroves (Avicennia marina) along the northern coasts of the Persian Gulf

Every ecosystem supports the living organisms by providing direct and indirect benefits and services. Among these areas, mangrove forests are one of the most fertile ecosystems in the intertidal zones. These natural forests are one of the coastal ecosystems that not only provide a source of food for humans and animals, but also play a major role in protecting and stabilizing coastlines and controlling climate. Mangroves are a breeding ground and a safe habitat for a variety of marine vertebrates and invertebrates. This study explains the experienced methods of propagation and foresting of Avicenna marina species. For the first time in the Persian Gulf, we reported a 5-year evaluation of reforestation method of grey mangrove. Reforestation in the highest latitude of natural forests in the Persian Gulf did not have any side effects on growing of Grey mangrove in the selected sites. As a result, increasing the area of Grey mangrove forests in the Persian Gulf improves the ecosystems of the tidal area. Increasing the chances of fishing and improving the economic conditions of the local communities around this bay will be some of the results of mangrove forestation. Furthermore, this is the first report of a simple method to train all the steps of grey mangrove reforestation.

Asymmetric Male Mating Success in Lek-Breeding Rhinella arenarum.

Mate choice is the attempt of an individual to gain higher reproductive fitness by preferring to mate with some individuals and not with others. We studied the role of mate choice in the mating system of the neotropical toad Rhinella arenarum by assessing male reproductive tactics for mate acquisition and the contribution of female choice for pair formation. In a shallow pond in central Argentina, we estimated male mating success and the corresponding reproductive tactics by focal observation. The variation of phenotypic and genotypic traits (size and shape, longevity, vocalization features, heterozygosity) was related to the observed mating success in 110 males. The phonotactic response of 21 reproductive females to conspecific advertisement call features was tested in arena experiments. Mating success was limited to 32 males, pair formation was size-assortative. The dominant reproductive tactics were advertising from call positions near suitable breeding sites and pre-mating fights with intruding males, whereas the interception of amplectant pairs and the displacement of mated males were never observed. Female phonotaxis was directed to conspecific choruses but complex and simple call structures were not distinguished. We conclude that the mating system is a lek combining pre-mating fights among males and female choice of slightly smaller males. Fights interfere with female choice, undermining size-assortative mating. This is a unique system in the R. marina species group, in which interception behavior dominates reproduction.

Detection and prevention of biological invasions in marinas and ports: Epibionts and associated fauna of Mytilus galloprovincialis revisited

Ports and marinas are gateways for introduction of non-indigenous species through ‘shipping’ worldwide. These anthropogenic environments concentrate a variety of artificial structures and substrates that are colonized by different types of organisms, being prone to biological invasions. One the most outstanding taxa in European marinas and ports are the mussels of the genus Mytilus. Mussels live in patches forming a three-dimensional, multi-layered and permanent biosubstrate that favours the settlement of sessile and mobile fauna, creating a perfect environment for the establishment and development of different species. In this study we characterized the biodiversity associated to the mussel patches of M. galloprovincialis in the Marina of Gijón (northern Spain, Cantabrian Sea), according to their status (i.e., native, introduced or alien, invasive and cryptogenic). The samples were collected from different areas of the marina: the outer dock (with national and international traffic), the middle dock and the inner one (both with local and national transit). We identified a total of 102 species associated to M. galloprovincialis, from which 13 and 4 species were invasive and alien respectively. The exotic fanworm Branchiomma luctusoum is reported for the first time in the Bay of Biscay and the Cantabrian Sea. The inner dock was the area with the highest number of non-indigenous taxa. Most of the alien and invasive species belonged to the groups Ascidiacea and Bryozoa, all of them filter feeders with great plasticity and ecological tolerance. Furthermore, the elemental composition microanalysis of the invasive bryozoan Watersipora subatra showed high levels of aluminium (a common element in marinas, being present in the fuel and in ship paintings), which may imply a risk of aluminium bioaccumulation in the environment. From these results we can conclude that mussel patches may facilitate the settlement and development of non-indigenous species in marinas, highlighting the importance of monitoring these mussel aggregations as a management tool for the early control and prevention of marine bioinvasions.

A Cyanobacteria Enriched Layer of Shark Bay Stromatolites Reveals a New Acaryochloris Strain Living in Near Infrared Light.

The genus Acaryochloris is unique among phototrophic organisms due to the dominance of chlorophyll d in its photosynthetic reaction centres and light-harvesting proteins. This allows Acaryochloris to capture light energy for photosynthesis over an extended spectrum of up to ~760 nm in the near infra-red (NIR) spectrum. Acaryochloris sp. has been reported in a variety of ecological niches, ranging from polar to tropical shallow aquatic sites. Here, we report a new Acarychloris strain isolated from an NIR-enriched stratified microbial layer 4–6 mm under the surface of stromatolite mats located in the Hamelin Pool of Shark Bay, Western Australia. Pigment analysis by spectrometry/fluorometry, flow cytometry and spectral confocal microscopy identifies unique patterns in pigment content that likely reflect niche adaption. For example, unlike the original A. marina species (type strain MBIC11017), this new strain, Acarychloris LARK001, shows little change in the chlorophyll d/a ratio in response to changes in light wavelength, displays a different Fv/Fm response and lacks detectable levels of phycocyanin. Indeed, 16S rRNA analysis supports the identity of the A. marina LARK001 strain as close to but distinct from from the A. marina HICR111A strain first isolated from Heron Island and previously found on the Great Barrier Reef under coral rubble on the reef flat. Taken together, A. marina LARK001 is a new cyanobacterial strain adapted to the stromatolite mats in Shark Bay.

Water eDNA metabarcoding is effective in detecting non-native species in marinas, but detection errors still hinder its use for passive monitoring

Marinas are high-priority targets for marine non-indigenous species (NIS), where they compose a large portion of the biofouling communities. The practicality of water samples collection makes environmental DNA (eDNA) metabarcoding an interesting tool for routine NIS surveys. Here the effectiveness of water-eDNA-metabarcoding to identify biofouling NIS, in 10 marinas from western France, was examined. Morphological identification of specimens collected in quadrats brought out 18 sessile benthic NIS beneath floating pontoons. Water-eDNA-metabarcoding detected two thirds of them, failing to detect important NIS. However, sampling and bioinformatics filtering steps can be optimized to identify more species. In addition, this method allowed the detection of additional NIS from neighboring micro-habitats. Caution should, however, be taken when reporting putative novel NIS, because of errors in species assignment. This work highlights that water-eDNA-metabarcoding is effective for active (targeted) NIS surveys and could be significantly improved for its further use in marine NIS passive surveys.

Produksi Serasah Daun Mangrove di Pulau Manomadehe Kecamatan Jailolo Selatan Kabupaten Halmahera Barat

The mangrove ecosystem is one of the ecosystems with high productivity due to the input of organic matter from litter. Litter production is the main supporter of fisheries potential, namely as a food source for aquatic biota. On Manomadehe Island, the community still continues to cut down mangroves to be used as firewood and building materials. Activities like this will result in damage to the mangrove forest and a decrease in the amount of litter production. Research objectives 1. To determine the amount of mangrove leaf litter production on Manomadehe Island, South Jailolo District, West Halmahera Regency. 2. Knowing the rate of decomposition of mangrove leaf litter on Manomadehe Island, South Jailolo District, West Halmahera Regency. This research was carried out in June-August 2020 using the purposive sampling method to determine stations, density (line transect plot), and litter-trap litter production. In general, the composition of mangrove species found at the study site on Manomadehe Island consisted of 3 families with 6 species (Rhizophora stylosa, Rhizophora apiculata, Rhizophora mucronata, Sonneratia alba, Avicennia marina, Avicennia lanata). Total production of mangrove leaf litter is 1276,59 grams/m2/60days, the highest is at Station 1 589,80 grams/m2/60days, Station 2 is 419,59 grams/m2/60days, Station 3267,21 grams/m2/60days. The highest litter contributor was Rhizophora stylosa 424,25 grams/m2/60days. Rhizophora apiculata 340,79 grams/m2/60days, Sonneratia alba 336,94 grams/m2/60days, Rhizophora mucronata 99,26 grams/m2/60days, Avicennia lanata 38,55 grams/m2/60days, Avicennia marina species are 36,80 grams/m2/60days.

A Multi-Faceted Approach to Understand How Resource Diversity Can Mediate the Coexistence of Cryptic Marine Nematode Species

Based on the principle of competitive exclusion, species occupying the same ecological niche cannot stably coexist due to strong interspecific competition for resources. Niche diversification, for instance through resource partitioning, may alleviate competition. Here, we investigate the effects of resource diversity on foraging behavior, fitness and interspecific interactions of four cryptic bacterivorous nematode species (Pm I–IV) of the Litoditis marina species complex with sympatric field distributions. Three resource (bacteria) diversity levels (low, medium, high) were used as food treatments and compared to a treatment with only Escherichia coli as food. Differences in taxis to food existed between the cryptic species and between bacterial mixtures of different diversity: all the cryptic species except Pm I showed higher attraction toward medium-diversity food. Furthermore, the cryptic species of L. marina generally exhibited higher fitness on a more diverse food resource. Resource diversity also impacted the interspecific interactions between the cryptic species. Our results show that resource diversity can alter the interspecific interactions among the cryptic species of L. marina, indicating that competitive equilibria between species are very context-dependent. Although a considerable body of evidence supports the hypotheses (e.g., “variance-in-edibility” hypothesis and the “dilution hypothesis” or “resource concentration hypothesis”) which predict a negative impact on consumers when resource diversity is increased, the benefits of a diverse resource can outweigh these disadvantages by offering a more complete and/or complementary range of nutritional resources as suggested by the “balanced diet” hypothesis.

Distribution and Population Structure of Avicennia marina (Forssk.) Vierh in Relation to the Environmental Gradient Along the Red Sea Coast of Egypt

Abstract This paper presents an assessment of changes in Avicennia marina population along the Egyptian coasts of the Red Sea. A retrospective analysis of the mangrove cover and distribution was carried out. The populations in Sharm El-Bahary and wadi El-Gimal lack at least one or more volume class stages, while all volume classes are represented in the last two populations occurring in wadi Al-Qu’lan and Sharm El-Madfa’a. The relationships between the individual diameter and canopy volume of A. marina population are simply linear. Strong correlation coefficients are obtained (r 2=0.92) for the population of Sharm El-Bahry and the weak correlation coefficients are obtained (r 2=0.63) for the population of wadi El-Gimal. On the other hand, the relationships between the individual heights and canopy volume of A. marina population are simply linear. Strong correlation coefficients are obtained (r 2=0.72) for the population of Sharm El-Bahry and the weak correlation coefficients are obtained (r 2=0.46) for the population of wadi El-Gimal. All growth performance of A. marina species differ significantly at the four localities except the circumference. The comparison of soil characteristics A. marina populations in the four study localities showed significant variations in all variables except the silt content and SO4.

The effects of heavy metals on the anatomical structures of Avicennia marina (Forssk.) Vierh

Anatomical changes observed in a mangrove plant, Avicenna marina, were studied with special reference to heavy metal pollution at Visakhapatnam Meghadrigedda creek area. The pollution in the region was very well reported to have been caused by the port activities and also by several major industries abutting the Meghadrigedda creek area. The concentrations of heavy metals, namely copper, chromium, cadmium, manganese, zinc, and lead, were determined using ICP-MS techniques. The heavy metal concentrations are more in sediments than in the native soils, whereas when focused on the role of mangroves, especially in Avicenna marina species, plants, exposed to higher concentrations, exhibited anatomical variations in the xylem of the stem and leaves also. The stem internal structure showed a xerophytic adaptation, with a thick cuticle, thick-walled cortex with an appearance as stone cells. The mainly noticeable characteristics are moist leaves, with expanded mesophyll area, thick cuticle with wax deposition shown on the epidermis. At lower concentrations, these changes did not exist. Bioconcentration factor (BCF) and translocation factor (TF) had been calculated to estimate the efficiency of a plant to accumulate heavy metals from sediment to its roots and translocate the heavy metals from its roots to its stems and leaves, in observed anatomical changes at higher concentrated area plants.

Assessment of Structure and Natural Regeneration Capacity of Avicennia Marina and Bruguiera Gymnorrhiza Species of Mangroves in Mida Creek Kilifi County, Kenya

The study assessed the structure, natural regeneration capacity and Biotic agents of Avicennia marina and Bruguiera gymnorrhiza species in Mida creek, Kilifi County. The study used both cross section and descriptive research design. Avicennia marina species was more dominant with a greater complexity index (A2.7, B0.4), basal area (A588cm2, B484cm2) and mean height (A26m, B10m) compared to Bruguiera gymnorrhiza species with both having an aggregate dispersion pattern. During dry season, Height, and diameter of Avicennia marina had a correlation of 0.56 while Bruguiera gymnorrhiza species had 0.78. During rainy season both had a correlation of 0.67. B. gymnorrhiza species had more straight poles than A. marina species, 75.3% of B. gymnorrhiza trees assessed had straight pole compared to 1.7% of Avicennia marina trees. Both Avicennia marina and Bruguiera gymnorrhiza species had fair regeneration capacity where the number of seedlings was greater than saplings and number of saplings was less than mature trees. Littoraria scabra fed mostly on micro-organisms and algae, Littoraria Glabrata fed mostly on mud surface, Sesarma guttata and Sesarma leptosoma fed on mangrove leaves, Cerithidea decollata fed on deposits and organic matter, Terebralia palustris and Selatium elongatium fed more on algae and leaves, Sesasrmi ortmanni, Metopograpsus oceanicus and Neosarmatium meinerti fed on leaves and young propagules, Barnacles and Oyster bunch on the roots and stems of B. gymnorrhiza species. Biotic agents were insignificant in affecting regeneration capacity of A. marina and B. gymnorrhiza species however combinations with climatic and anthropogenic factors affected Regeneration capacity of the two species.

Modeling Mangrove Above-Ground Biomass Using Terrestrial Laser Scanning Techniques: A Case Study of the Avicennia marina Species in the Bang Pu District, Thailand

Deterioration of tropical mangrove forests is one of the most serious problems of the world's coastal ecosystems. Mangrove above-ground biomass (AGB) modeling is the key to support the management and rejuvenation of these ecosystems. Nevertheless, it is illegal to observe tree data using the destructive methods in reserved mangrove forests for acquiring tree allometric models. Thus, this study proposed a non-destructive alternative, the use of a terrestrial laser scanner (TLS) technique. The study site dominated by Avicennia marina (Forsk.) Veirh (A. marina) was located in the Bang Pu conservation area, Thailand. The tree structures were quantified and tested in this study. A Quantitative Structural Model (QSM) was chosen for the calculation of the tree stem volume. Then, the TLS allometric model was generated via a power function. The RMSE between the presented model and the four reference A. marina models were reported in this study. The largest RMSE errors (i.e., 40% and 35%) were found when comparing the TLS allometric model to the two generic allometric models. On the other hand, the outcomes of the species-specific models were closer to the outcome of this study (i.e., the RMSE errors are less than 20%). The disagreement between the proposed TLS model and the generic mangrove model suggested that a species-specific model is needed for more accurate results. It is anticipated that the methodology presented in this study may be used as standard procedures for producing the A. marina allometric model in other areas.

The roles of vicariance and dispersal in the differentiation of two species of the Rhinella marina species complex

The high levels of Neotropical biodiversity are commonly associated with the intense Neogene-Quaternary geological events and climate dynamics. Here, we investigate the evolutionary history of two species of Neotropical closely related amphibians (R. horribilis and R. marina). We combine published data with new mitochondrial DNA sequences and multiple nuclear markers, including 12 microsatellites. The phylogenetic analyses showed support for grouping the samples in two main clades; R. horribilis (Central America and Mexico) and R. marina (South America east of the Andes). However, the phylogenetic inferences also show an evident mito-nuclear discordance. We use Approximate Bayesian Computation (ABC) to test the role of different events in the diversification between the two groups recovered. We found that both species were affected primarily by a recent Pleistocene divergence, which was similar to the divergence estimate revealed by the Isolation-with-Migration model, under persistent bidirectional gene flow through time. We provide the first evidence that R. horribilis is differentiated from the South American R. marina at the nuclear level supporting the taxonomic status of R. horribilis, which has been controversial for more than a century.

Mangrove Species Diversity in Coastal Village swollen Banyuwangi Regency

The Bengkak coastal area is one of the coastal areas which is a marine fishery activity with a natural mangrove ecosystem of ± 9 ha bordered by reed mangrove and opposite to TN West Bali mangrove. Environmental pressure with the presence of human activities such as the extraction of mangrove wood causes the growth and development of mangroves not optimal and affects the potential of mangrove ecosystems so research needs to be done to determine the diversity of mangrove ecosystems on the coast of Bengkak Village, Banyuwangi District. Observations in the whole mangrove ecosystem have low species diversity criteria, namely H 'ranging from 0.20 - 0.67 and dominated by A. marina species from the families Avicenniaceae and R. mucronata from the family Rhizophoraceae. While the density of species in all observation stations found that mangrove stands ranged from 967 - 82,000 Ind / Ha. The density of A. marina mangrove vegetation was identified as the highest in the seedling phase of 7,500 Ind / Ha, the sapling phase was 74,000 Ind / Ha and the tree phase was 567 Ind / Ha. The lowest type of R. mucronata was identified in the seedling phase of 5,000 Ind / Ha, sapling phase of 8,000 Ind / Ha and tree phase of 400 Ind / Ha. Environmental factors in the form of nutrients such as leaf litter and the quality of the aquatic environment also influence the growth and development of mangrove ecosystems. environmental conditions in the mangrove zone have the texture of sandy soil and sandy mud, temperatures range from 23 - 33 °C, pH ranges from 7 and salinity ranges from 23 - 36 "°. These environmental conditions support the growth and development of the species of mangrove Avicennia sp. and Rhizopora sp. so that it is dominant and spreads on the coast of Bengkak Village.