Morphological and Molecular Evolution Are Not Linked in Lamellodiscus (Plathyhelminthes, Monogenea)

Lamellodiscus Johnston & Tiegs 1922 (Monogenea, Diplectanidae) is a genus of common parasites on the gills of sparid fishes. Here we show that this genus is probably undergoing a fast molecular diversification, as reflected by the important genetic variability observed within three molecular markers (partial nuclear 18S rDNA, Internal Transcribed Spacer 1, and mitonchondrial Cytochrome Oxidase I). Using an updated phylogeny of this genus, we show that molecular and morphological evolution are weakly correlated, and that most of the morphologically defined taxonomical units are not consistent with the molecular data. We suggest that Lamellodiscus morphology is probably constrained by strong environmental (host-induced) pressure, and discuss why this result can apply to other taxa. Genetic variability within nuclear 18S and mitochondrial COI genes are compared for several monogenean genera, as this measure may reflect the level of diversification within a genus. Overall our results suggest that cryptic speciation events may occur within Lamellodiscus, and discuss the links between morphological and molecular evolution

Approaches in biotechnological applications of natural polymers

Natural polymers, such as gums and mucilage, are biocompatible, cheap, easily available and non-toxic materials of native origin. These polymers are increasingly preferred over synthetic materials for industrial applications due to their intrinsic properties, as well as they are considered alternative sources of raw materials since they present characteristics of sustainability, biodegradability and biosafety. As definition, gums and mucilages are polysaccharides or complex carbohydrates consisting of one or more monosaccharides or their derivatives linked in bewildering variety of linkages and structures. Natural gums are considered polysaccharides naturally occurring in varieties of plant seeds and exudates, tree or shrub exudates, seaweed extracts, fungi, bacteria, and animal sources. Water-soluble gums, also known as hydrocolloids, are considered exudates and are pathological products; therefore, they do not form a part of cell wall. On the other hand, mucilages are part of cell and physiological products. It is important to highlight that gums represent the largest amounts of polymer materials derived from plants. Gums have enormously large and broad applications in both food and non-food industries, being commonly used as thickening, binding, emulsifying, suspending, stabilizing agents and matrices for drug release in pharmaceutical and cosmetic industries. In the food industry, their gelling properties and the ability to mold edible films and coatings are extensively studied. The use of gums depends on the intrinsic properties that they provide, often at costs below those of synthetic polymers. For upgrading the value of gums, they are being processed into various forms, including the most recent nanomaterials, for various biotechnological applications. Thus, the main natural polymers including galactomannans, cellulose, chitin, agar, carrageenan, alginate, cashew gum, pectin and starch, in addition to the current researches about them are reviewed in this article.. }To the Conselho Nacional de Desenvolvimento Cientfíico e Tecnológico (CNPq) for fellowships (LCBBC and MGCC) and the Coordenação de Aperfeiçoamento de Pessoal de Nvíel Superior (CAPES) (PBSA). This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit, the Project RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462) and COMPETE 2020 (POCI-01-0145-FEDER-006684) (JAT)

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Proposition de Scalithrium n. gen. (Cestoda, Tetraphyllidea) avec comme espèce-type Scalithrium minimum (Van Beneden, 1850) n. comb. parasite de Dasyatis pastinaca (Elasmsobranchii, Dasyatidae)

Un nouveau genre Scalithrium (Tetraphyllidea, Phyllobothriidae, Rhinebothriinae) est proposé pour les espèces de Rhinebothrium possédant un scolex à quatre bothridies à surface distale subdivisée en une seule rangée de loculi par des septa transverses. Scalithrium minimum (Van Beneden, 1850) n. comb, est redécrit à partir d'individus récoltés en Tunisie chez l'hôte type Dasyatis pastinaca, et devient l'espèce-type du nouveau genre. Suivant Braun (1900) Echeneibothrium variabile Van Beneden, 1850 est considéré comme l'espèce-type du genre Echeneibothrium. On discute des Rhinebothriinae à placer dans le genre Scalithrium et une clé de détermination des huit espèces retenues est proposée

Proposition de

Un nouveau genre Scalithrium (Tetraphyllidea, Phyllobothriidae, Rhinebothriinae) est proposé pour les espèces de Rhinebothrium possédant un scolex à quatre bothridies à surface distale subdivisée en une seule rangée de loculi par des septa transverses. Scalithrium minimum (Van Beneden, 1850) n. comb, est redécrit à partir d'individus récoltés en Tunisie chez l'hôte type Dasyatis pastinaca, et devient l'espèce-type du nouveau genre. Suivant Braun (1900) Echeneibothrium variabile Van Beneden, 1850 est considéré comme l'espèce-type du genre Echeneibothrium. On discute des Rhinebothriinae à placer dans le genre Scalithrium et une clé de détermination des huit espèces retenues est proposée

gn. et sp.n. (Monogenea, Monocotylidae) parasite branchial de

Quinze Pteromylaeus bovinus (Geoffroy St. Hilaire), péchés en divers points de la côte tunisienne, ont été examinés entre 1996 et 1998 pour l'étude de leurs parasites. Myliocotyle pteromylaei gn. et sp. n., récolté sur les branchies de douze individus hôtes, est décrit et illustré. Le genre et l'espèce diffèrent des autres Heterocotylinae par le nombre et la morphologie des structures dorsales du hapteur, la disposition et le nombre des glandes antérieures et la morphologie du pénis. O. pteromylaei marque avec Heliocotyle kartasi l'originalité des Monocotylidae parasites branchiaux de Pteromylaeus bovinus

Lamellodiscus sanfilippoi n. sp. (Monogenea, Diplectanidae) parasite branchial de Diplodus sargus (Teleostei, Sparidae) en Méditerranée

Lamellodiscus sanfilippoi n. sp. entre, parmi les Lamellodiscus, dans le sous-groupe “ergensi” (Amine et Euzet, 2005), caractérisé par la morphologie des barres latérales dorsales du hapteur. Ce sous-groupe comprend, en Méditerranée, L. ergensi Euzet et Oliver, 1966, L. kechemirae Amine et Euzet, 2005 et L. tomentosus Amine et Euzet, 2005 parasites de Diplodus sargus, ainsi que L. baeri Oliver, 1974 parasite de Pagrus pagrus. L. sanfilippoi se distingue de ces espèces par la morphologie et la taille des barres latérales dorsales du hapteur. L’espèce se rapproche de Lamellodiscus furcillatus Kritsky, Jiménez-Ruíz et Sey, 2000, parasite de Diplodus noct du golfe Persique, mais s’en distingue par l’épaisseur des pièces du hapteur et la morphologie de l’appareil copulateur mâle. Lamellodiscus gussevi Sanfilippo (1978) et Lamellodiscus abbreviatus Sanfilippo (1978) sont considérés comme des nomina nuda

Lamellodiscus sanfilippoi

Lamellodiscus sanfilippoi n. sp. entre, parmi les Lamellodiscus, dans le sous-groupe “ergensi” (Amine et Euzet, 2005), caractérisé par la morphologie des barres latérales dorsales du hapteur. Ce sous-groupe comprend, en Méditerranée, L. ergensi Euzet et Oliver, 1966, L. kechemirae Amine et Euzet, 2005 et L. tomentosus Amine et Euzet, 2005 parasites de Diplodus sargus, ainsi que L. baeri Oliver, 1974 parasite de Pagrus pagrus. L. sanfilippoi se distingue de ces espèces par la morphologie et la taille des barres latérales dorsales du hapteur. L’espèce se rapproche de Lamellodiscus furcillatus Kritsky, Jiménez-Ruíz et Sey, 2000, parasite de Diplodus noct du golfe Persique, mais s’en distingue par l’épaisseur des pièces du hapteur et la morphologie de l’appareil copulateur mâle. Lamellodiscus gussevi Sanfilippo (1978) et Lamellodiscus abbreviatus Sanfilippo (1978) sont considérés comme des nomina nuda

Reproductive biology of Klein’s sole, Synapturichthys kleinii (Actinopterygii: Pleuronectiformes: Soleidae), off Tunisian coast (central Mediterranean)

Background. Klein’s sole, Synapturichthys kleinii (Risso, 1827), is a rare fish, included in the IUCN Red List as Data Deficient, and its biology is poorly known. Biological investigations of S. kleinii have been surprisingly rare in Tunisian waters. In the presently reported study, we investigated the reproductive period, size at first sexual maturity, and fecundity of S. kleinii along the Tunisian waters, with the aim of achieving the first complete and comprehensive description of the reproduction of this fish in the Mediterranean Sea. Materials and methods. A total of 294 specimens of S. kleinii were sampled over two years, off the Tunisian coasts. Sex ratio was estimated through the seasons of the year and the size classes. The stage of maturity was determined macroscopically only for females. Monthly gonadosomatic index (GSI), monthly hepatosomatic index (HSI), and condition factor (K) were calculated for males and females of S. kleinii. Size at first maturity was estimated only for females during the spawning season. Eighteen mature females at spawning stage were collected, weighed, and fixed in 4% formaldehyde solution for fecundity estimation. Results. Annual sex ratio showed significant differences between males and females. In specimens exceeding 27 cm in total length females outnumbered males significantly. The Klein’s sole reproduction period started in October and ended in January. The gonadosomatic index reached highest values in November for females and males. Females attained sexual maturity at 20.53 cm total body length (TL). Total fecundity ranged from 3647 to 23 174 eggs. We found a low correlation coefficient between total fecundity and total length, but a high correlation coefficient between eviscerated weight and ovary weight. Conclusion. Our results constitute a preliminary baseline for monitoring changes in the biological indexes linked to the reproduction cycle and length at first sexual maturity of S. kleinii. The presently acquired data will enable biologists to assess the status of this fish and develop culture technology in natural waters and will be useful for the fishery biologists and conservation biologists, for successful development, management, production, and ultimate conservation of this favoured Tunisian food fish

Digenean species diversity in teleost fishes from the Gulf of Gabes, Tunisia (Western Mediterranean)

This study is the first attempt to survey the diversity of fish digeneans in the Gulf of Gabes (southern coast of Tunisia). A total of 779 fishes belonging to 32 species were sampled. 53 species of Digenea belonging to 15 families were recorded. Among these species, 24 are reported for the first time from the coast of Tunisia. We report one new host record, Lecithochirium sp. from Sardinella aurita. The Hemiuridae is the dominant family. A host-parasite list is presented with the information on the prevalence, abundance and mean intensity of each species collected. The diversity of Digenea is compared with other localities in the Mediterranean Sea and the northern east of Tunisia. The Gulf of Gabes shows the lowest diversity linked to the anthropogenic activities and impact of exotic species. The use of Digenea as indicators of the state of the ecosystem is discussed