Morphological and molecular characterization of freshwater prawn of genus Macrobrachium in the coastal area of Cameroon

Macrobrachium (Bate, 1868) is a large and cosmopolitan crustacean genus of high economic importance worldwide. We investigated the morphological and molecular identification of freshwater prawns of the genus Macrobrachium in South, South West, and Littoral regions of Cameroon. A total of 1,566 specimens were examined morphologically using a key described by Konan (Diversité morphologique et génétique des crevettes des genres Atya Leach, 1816 et Macrobrachium Bate, 1868 de Côte d'Ivoire, 2009, Université d'Abobo Adjamé, Côte d'Ivoire), leading to the identification of seven species of Macrobrachium: M. vollenhovenii (Herklots, 1857); M. macrobrachion (Herklots, 1851); M. sollaudii (De Man, 1912); M. dux (Lenz, 1910); M. chevalieri (Roux, 1935); M. felicinum (Holthuis, 1949); and an undescribed Macrobrachium species M. sp. To validate the genetic basis of the identified species, 94 individuals representing the species were selected and subjected to genetic characterization using 1,814 DArT markers. The admixture analysis revealed four groups: M. vollenhovenii and M. macrobrachion; M. chevalieri; M. felicinum and M. sp; and M. dux and M. sollaudii. But, the principal component analysis (PCA) separated M. sp and M. felicinum to create additional group (i.e., five groups). Based on these findings, M. vollenhovenii and M. macrobrachion may be conspecific, as well as M. dux and M. sollaudii, while M. felicinum and M. sp seems to be different species, suggesting a potential conflict between the morphological identification key and the genetic basis underlying speciation and species allocation for Macrobrachium. These results are valuable in informing breeding design and genetic resource conservation programs for Macrobrachium in Africa.     

A Revision of Australian River Prawns, Macrobrachium (Crustacea: Decapoda: Palaemonidae)

A taxonomic revision of Australian Macrobrachium identified three species new to the Australian fauna – two undescribed species and one new record, viz. M. auratumsp. nov., M. koombooloombasp. nov., and M. mammillodactylus(Thallwitz, 1892). Eight taxa previously described by Riek (1951) are recognised as new junior subjective synonyms, viz. M. adscitum adscitum, M. atactum atactum, M. atactum ischnomorphum, M. atactum sobrinum, M. australiense crassum, M. australiense cristatum, M. australiense eupharum of M. australienseHolthuis, 1950, and M. glypticumof M. handschiniRoux, 1933. Apart from an erroneous type locality for a junior subjective synonym, there were no records to confirm the presence of M. australe(Guérin-Méneville, 1838) on the Australian continent. In total, 13 species of Macrobrachiumare recorded from the Australian continent. Keys to male developmental stages and Australian species are provided. A revised diagnosis is given for the genus. A list of 31 atypical species which do not appear to be based on fully developed males or which require re-evaluation of their generic status is provided. Terminology applied to spines and setae is revised.     

Exotic species of freshwater decapod crustaceans in the state of São Paulo,Brazil: records and possible causes of their introduction

Based on recent surveys of the freshwater decapod fauna, distributional data of five exotic species of freshwater decapod crustaceans for the hydrographic basins of the state of São Paulo are presented, as part of a large initiative for a comprehensive survey of the state’s biodiversity (BIOTA-FAPESP Program). These species are the North American crayfish Procambarus clarkii (Girard) (Cambaridae), the crab Dilocarcinus pagei Stimpson (Trichodactylidae) from the Amazon and Paraguay/lower Paraná River Basins, and the palaemonid shrimps Macrobrachium rosenbergii (De Man), from the Indo-Pacific region, Macrobrachium amazonicum (Heller) and Macrobrachium jelskii (Miers), both from the Orinoco, Amazon and the Paraguay/lower Paraná River Basins. Possible modes by which their introduction might have occurred are commented upon and potential consequences are discussed.     

Heterochrony in mandible development of larval shrimp (Decapoda: Caridea)—A comparative morphological SEM study of two carideans

Mandible development in the larval stages I–V of two palaemonid shrimp species, Palaemon elegans and Macrobrachium amazonicum, was analyzed using scanning electron microscopy, light microscopy, and confocal laser scanning microscopy. In contrast to the zoea I of P. elegans, first‐stage larvae of M. amazonicum are nonfeeding. At hatching, the morphology of the mandibles is fully expressed in P. elegans, while it appears underdeveloped in M. amazonicum, presenting only small precursors of typical caridean features. In successive zoeal stages, both species show similar developmental changes, but the mandibular characters of the larvae in M. amazonicum were delayed compared to the equivalent stages in P. elegans, especially in the development of submarginal setae and mandible size. In conclusion, our results indicate heterochrony (postdisplacement) of mandible development in M. amazonicum compared to that in P. elegans, which is related to initial lack of mandible functionality or planktivorous feeding at hatching, respectively. This conclusion is supported by comparison with other palaemonid zoeae exhibiting different feeding modes. Our data suggest that an evolutionary ground pattern of mandible morphology is present even in species with nonfeeding first‐stage larvae. J. Morphol. 275:1258–1272, 2014. © 2014 Wiley Periodicals, Inc.     

Muscle water control in crustaceans and fishes as a function of habitat, osmoregulatory capacity, and degree of euryhalinity

This study aimed at detecting possible patterns in the relationship between Anisosmotic Extracellular Regulation (AER) and Isosmotic Intracellular Regulation (IIR) in crustaceans and teleost fish from different habitats and evolutionary histories in fresh water (FW), thus different osmoregulatory capabilities, and degrees of euryhalinity. Crustaceans used were the hololimnetic FW Aegla schmitti, and Macrobrachium potiuna, the diadromous FW Macrobrachium acanthurus, the estuarine Palaemon pandaliformis and the marine Hepatus pudibundus; fishes used were the FW Corydoras ehrhardti, Mimagoniates microlepis, and Geophagus brasiliensis, and the marine-estuarine Diapterus auratus. The capacity for IIR was assessed in vitro following wet weight changes of isolated muscle slices incubated in anisosmotic saline (~ 50% change). M. potiuna was the crustacean with the highest capacity for IIR; the euryhaline perciforms G. brasiliensis and D. auratus displayed total capacity for IIR. It is proposed that a high capacity for IIR is required for invading a new habitat, but that it is later lost after a long time of evolution in a stable habitat, such as in the FW anomuran crab A. schmitti, and the Ostariophysian fishes C. ehrhardti and M. microlepis. More recent FW invaders such as the palaemonid shrimps (M. potiuna and M. acanthurus) and the cichlid G. brasiliensis are euryhaline and still display a high capacity for IIR.     

Reproductive potential of four freshwater prawn species in the Amazon region

The bioecology of freshwater prawns can be understood by studying their reproductive biology. Thus, the aim of this paper was to determine and compare the reproductive potential of four freshwater caridean prawns collected in the Amazon region. For two years, we captured females of Macrobrachium brasiliense, Palaemon carteri, Pseudopalaemon chryseus and Euryrhynchus amazoniensis from inland streams in the municipality of Itacoatiara (AM). At the laboratory, we measured the biometric variables total length, carapace length, abdomen length and total weight, and recorded the number of eggs (NE) by direct counting. There was a significant difference for all variables between the species. The females of M. brasiliense were the most abundant and had the largest sizes and NE. However, the fecundity index shows that P. carteri has the highest reproductive potential of the four species. Despite the differences in size and weight, all the species showed low fecundity, which is a characteristic of continental palemonidean K strategist prawns.     

Complete mitochondrial genome of the Japanese snapping shrimp Alpheus japonicus (Crustacea: Decapoda: Caridea): Gene rearrangement and phylogeny within Caridea

The complete sequence of the mitochondrial genome of the Japanese snapping shrimp Alpheus japonicus Miers (Crustacea: Decapoda: Caridea) is presented here. A comparative analysis based on the currently available mitochondrial genomic data revealed many previously unknown characteristics of the mitochondrial genomes of caridean shrimps. The A. japonicus mitochondrial genome is 16487 bp long and contains the typical set of 37 metazoan genes. The gene arrangements in the mitochondrial genomes of four previously studied carideans (Macrobrachium rosenbergii, M. nipponense, M. lanchesteri and Halocaridina rubra) were found to be identical to the pancrustacean ground pattern; thus, it was considered that gene rearrangements probably did not occur in the suborder Caridea. In the present study, a translocation of the trnE gene involving inversion was found in Alpheus mitochondrial genomes. This phenomenon has not been reported in any other crustacean mitochondrial genome that has been studied so far; however, the translocation of one transfer RNA gene (trnP or trnT) was reported in the mitochondrial genome of Exopalaemon carinicauda. When the ratios of the nonsynonymous and synonymous substitutions rates (Ka/Ks) for the 13 protein coding genes from two Alpheus species (A. japonicus and A. distinguendus) and three Macrobrachium species (M. rosenbergii, M. nipponense, M. lanchesteri) were calculated, the Ka/Ks values for all the protein coding genes in Alpheus and Macrobrachium mitochondrial genomes were found to be less than 1 (between 0.0048 and 0.2057), indicating that a strong purification selection had occurred. The phylogenetic tree that was constructed based on the mitochondrial protein coding genes in the genomes of nine related species indicated that Palaemonidae and Alpheidae formed a monophyly and shared a statistically significant relationship, (Palaemonidae+Alpheidae)+Atyidae, at the family level.     

Taxonomic revision of the land snail genera Macrochlamys Gray, 1847 and Sarika Godwin-Austen, 1907 (Eupulmonata: Ariophantidae) from south-eastern Myanmar,with descriptions of three new species

ABSTRACT

Knowledge of Myanmar land snails is based on the late eighteenth to early twentieth century literature and many species need to be re-investigated, especially in the genera Macrochlamys Gray, 1847 and Sarika Godwin-Austen, 1907. In order to update this knowledge, this paper presents information on these two related genera based on new materials from south-eastern Myanmar. Fifteen species are recognised in the south-east of Myanmar. Of these, live material was available for eight Macrochlamys and Sarika species and these are described in full herein, based on data from the shell, external morphology and genitalia, including three species new to science (M. brachystia n. sp., S. concavata n. sp. and S. lopa n. sp.) and five species redescribed (M. aspides, M. kelantanensis, M. petasus, S. consepta and S. obesior). The remaining five species are known only from their shell morphology (M. cauisa, M. perpaula, M. poongee, M. salwinensis and S. birmana) and two species are known from genitalia (S. dugasti and S. resplendens). For these species the shells are figured and some taxonomic remarks are provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:58D2A9E7-50FD-49C2-B2F4-4D00457EA331     

The conquest of fresh water by the palaemonid shrimps: an evolutionary history scripted in the osmoregulatory epithelia of the gills and antennal glands

Extant Palaemonidae occupy aquatic environments that have generated physiological diversity during their evolutionary history. We analyze ultrastructural traits in gills and antennal glands of palaemonid species from distinct osmotic niches, and employ phylogenetic comparative methods to ascertain whether transformations in their osmoregulatory epithelia have evolved in tandem, driven by salinity. Gill pillar cells exhibit apical evaginations whose surface density (S_v, μm² plasma membrane area/μm³ cytoplasmic volume) ranges from 6.3–7.1 in Palaemon, and 0.7–38.4 in Macrobrachium. In the septal cells, S_v varies from 8.9–10.0 in Palaemon, and 3.3–21.6 in Macrobrachium; mitochondrial volumes (V_mit) range from 43.3–46.8% in Palaemon and 34.9–53.4% in Macrobrachium. In the renal proximal tubule cells, apical microvilli S_v varies from 27.0–34.3 in Palaemon, and 38.3–47.8 in Macrobrachium; basal invagination S_v ranges from 18.7–20.0 in Palaemon and 30.8–40.8 in Macrobrachium. Septal cell S_v shows phylogenetic signal; evagination height/density, apical S_v, and V_mit vary independently of species relatedness. Salt transport capability by the gill and renal epithelia has increased during palaemonid evolution, reflecting amplified membrane availability for ion transporter insertion. These traits underpin the increased osmotic gradients maintained against the external media. Gill ultrastructure and osmotic gradient have evolved in tandem, driven by salinity at the genus level. © 2015 The Linnean Society of London, Biological Journal of the Linnean Society, 2015, 114 , 673–688.     

Adaptive patterns of osmotic and ionic regulation, and the invasion of fresh water by the palaemonid shrimps

To evaluate trends in the osmoregulatory behavior of neotropical, palaemonid shrimps, we investigated osmotic and ionic regulatory patterns in five species of Palaemon or Macrobrachium. The species' life histories depend on saline water to differing degrees, their habitats ranging from the marine/intertidal (P. northropi), through estuaries (P. pandaliformis) to coastal, freshwater streams (M. olfersii, M. potiuna) and inland, continental river systems (M. brasiliense). Hemolymph osmolality, chloride, sodium and magnesium concentrations were measured in shrimps exposed to experimental media ranging from fresh water (<0.5 per thousand ) to concentrated seawater (42 per thousand ) for up to 10 days. The marine and estuarine Palaemon species exhibit well-developed hyper/hypo-osmotic, sodium and chloride regulatory capabilities in mid-range salinities, tending to hyperconform in low salinities. The freshwater Macrobrachium species show variable hyperosmotic, sodium and chloride regulatory capacities, tending to hypoconform or unable to survive at higher salinities. All species hyper-regulate magnesium in fresh water, but hyporegulate strongly in saline media. Palaemonids from the saline habitats show the strongest osmoregulatory capabilities, and fresh water may have been gradually invaded by ancestral species with similar regulatory capacity. However, this regulatory plasticity has been lost to varying degrees in extant freshwater species.     

Revision of Asian species of the Drosophila melanica species group (Diptera: Drosophilidae), with a description of a new species from Vietnam

A new species of the Drosophila (Drosophila) melanica species group (Diptera: Drosophilidae), Drosophila denruoi Suwito & Watabe, sp. nov., is described from northern Vietnam. It is proved by crossing experiments that reproductive isolation is complete between this species and other morphologically similar species. Larval ganglion cells of D. denruoi possess 2n = 12 chromosomes, comprised of four pairs of acrocentric, one pair of metacentric and one pair of micro‐chromosomes. This is the largest number of acrocentric chromosomes in the group and implies that the species has the most primitive chromosomal configuration in the melanica group. Based on the results of crossing experiments and close morphological examination, Drosophila pengi Okada & Kurokawa, 1957 from central Japan, once regarded as a synonym of Drosophila tsigana Burla & Gloor, 1952, is shown to be distinct from D. tsigana. Drosophila pengi is thus resurrected as a member of the melanica group. We synonymize Drosophila bisetata Toda, 1988, described from central Myanmar, with D. pengi. In addition, a population from Guizhou, southwestern China, once regarded as D. tsigana, is also identified as D. pengi. These populations from central Myanmar and southwestern China share the diagnostic characters of D. pengi. At the same time, it is reconfirmed that the Hokkaido population is conspecific with European D. tsigana. Furthermore, another species, Drosophila longiserrata Toda, 1988 described from central Myanmar, is synonymized with Drosophila afer Tan, Hsu & Sheng, 1949 from China, based on their having identical karyotypes and external morphology.     

Influence of lecithotrofic feeding on growth and development of larvae of freshwater prawn <Emphasis Type="Italic">Macrobrachium rosenbergii</Emphasis>

In the giant freshwater prawn Macrobrachium rosenbergii (De Man), lecithotrofic feeding was discovered at the zoea I stage, and facultative lecithotrofic feeding was found at the zoea II stage. Cases of the completion of the first two stages without feeding were detected. However, a delay in feeding at the zoea II stage caused the inhibition of the growth and development of larvae. In this connection, we recommend to introduce food to the aquaculture of the giant freshwater prawn on the end of the first day after hatching, when the first zoea II larvae emerge.     

Regional scale speciation reveals multiple invasions of freshwater in Palaemoninae (Decapoda)

Ashelby, C.W., Page, T.J., De Grave, S., Hughes, J.M. & Johnson, M.L. (2012) Regional scale speciation reveals multiple invasions of freshwater in Palaemoninae (Decapoda). —Zoologica Scripta, 41, 293–306. The generic level, systematic relationship in Palaemoninae was inferred from analyses based on the mitochondrial 16S rDNA and nuclear Histone (H3) genes, primarily focussed on the genera Palaemon and Palaemonetes, as previous morphological and molecular studies indicated potential paraphyly in some genera. Palaemonetes, Exopalaemon, Coutierella and certain Palaemon recover as a strongly supported monophyletic clade, but with the exception of Palaemon concinnus, P. pandaliformis and P. gracilis. Within this clade, six major clades are identified with geographic relationships appearing stronger than generic relationships. The data strongly suggest that Palaemon, Palaemonetes, Exopalaemon and Coutierella are synonymous and that the morphological characters currently used to define these genera require re‐evaluation. Freshwater species are not closely related to each other, but instead group with geographically close marine species, suggesting multiple invasions of freshwater by physiologically plastic ancestors rather than a single colonisation event with subsequent speciation.     

Molineria jashpurica sp. nov. (Hypoxidaceae) from Central India

Molineria jashpurica A.P. Tiwari, Mujaffar & A.N. Shukla (Hypoxidaceae), a new species from the Jashpur district of Chhattisgrah, India is described and illustrated. It is closely similar to M. gracilis and M. trichocarpa, but differs by shorter pseudopetiole, broad and glabrous leaf blade, delicate scape, fewer flowers and clavate stigma. A key for identification of all Molineria species is also provided. The conservation status of the new species is assessed as ‘Critically Endangered’ (CR) according to IUCN red list category and criteria.     

Life history traits of shrimps (Decapoda: Palaemonidae) of Amazonian inland waters and their Phylogenetic interpretation

Amazonian shrimps (Decapoda, Palaemonidae) of several genera from the generally nutrient‐poor, acid waters of the Rio Negro basin show two different breeding patterns: in the annually inundated (Jan./Feb. to Sept./Oct.) lowland forest (= “igapó") they breed during a period with rising and high water levels only (Dec. to July); in the headwater streams draining the “terra firme”; (= regions not subject to annual inundations), the same species breed continuously the year round. All species from these nutrient‐poor and hence, plankton‐deficient, waters have abreviated life cycles with 1–3 benthic larval stages; this includes several Macrobrachium species. However, Macrobrachium amazonicum from the plankton‐rich floodplain lakes, which are fed by the richer water of the Amazon river, maintains the marine pattern of development with numerous stages of filter‐feeding, planktonic larvae. Phylogenetic convergence (several genera developing independently the same adaptive pattern) and divergence (the same genus/species exhibiting different patterns in different environments) are discussed in relation to recent, general molecular genetics.     

Ultraconserved elements put the final nail in the coffin of traditional use of the genus Meliphaga (Aves: Meliphagidae)

Molecular systematics is bringing taxonomy into the 21st Century by updating our nomenclature to reflect phylogenetic relationships of taxa. This transformation is evidenced by massive changes in avian taxonomy, ranging from ordinal to subspecies changes. In this study, we employ target capture of ultraconserved elements to resolve genus‐level systematics of a problematic group of honeyeaters (Aves: Meliphagidae). With near complete species‐level taxon sampling of the Australo‐Papuan species within the traditionally recognized Meliphaga and Oreornis, we investigate generic limits using a genomic dataset. Likelihood and species tree methods confirm two clades within this group and found the New Guinea endemic Oreornis chrysogenys embedded within one of these clades. Our study supports earlier recommendations that Meliphaga Lewin, 1808 should be restricted to three species, M. aruensis, M. lewinii and M. notata. We make a case for recognizing three genera in the remaining species, Oreornis van Oort, 1910, Microptilotis Mathews, 1912 and Territornis Mathews, 1924.     

Molecular characterization of Morchella species from the Western Himalayan region of India

The molecular diversity of thirty-two different Morchella cultures/fruiting bodies, collected from the Western Himalayan region was studied in this investigation. Considerable taxonomic confusion exists regarding many species of Morchella. Although classical taxonomy is helpful in identification for many ascomycetes, morels exhibit considerable morphological diversity and there is disagreement in the identification of morel species. Phylogenetic analyses based on DNA sequences could help in sorting out morel taxonomy which is essential to better define the morel diversity. In this study, sequence analysis revealed that in the Western Himalayan region of India, both yellow (M. crassipes, M. spongiola) and black morels (M. elata, M. angusticeps, and M. gigas) were prominent along with two Verpa species. Phylogenetic analysis by maximum parsimony, maximum likelihood and Bayesian inference revealed two different clades and a clear distinction between yellow and black morels.     

Carnitine: a novel compatible solute in Lactobacillus plantarum

The aim of this study was to unravel the identity of compatible solutes accumulated by Lactobacillus plantarum subjected to osmotic stress. Betaine was accumulated simulataneously with a novel compatible solute identified as carnitine, both present in the complex medium applied in this study. Beef extract provided the main source of carnitine in the medium. Both carnitine and betaine were accumulated to maximum concentrations of 248 and 231 mol.g dry weight^-1, respectively. A defined medium was devised devoid of carnitine. Addition of 0.5 mM carnitine to this medium increased the growth rate from 0.1 h^-1 to 0.2 h^-1 in media with 0.4 M sodium chloride. Also, carnitine made the organism more tolerant to sodium chloride. Growth occurred even when the sodium chloride concentration was raised from 0.5 M to 1.0 M. Quaternary compounds resembling the structure of carnitine and betaine enhanced the growth yield as well. -Butyrobetaine and succinylcholine restored the growth yield up to respectively 91 and 96% compared to non-stressed cells.Abbreviation MRS De Man, Rogosa and Sharpe (De Man et al. 1960)