Two new species of Metacyclops Kiefer, 1927 (Copepoda, Cyclopoida) from Thailand and an up-to-date key to the species recorded in Asia

Metacyclops sakaeratensis sp. nov. and M. brancelji sp. nov. are described as being present in the mountainous areas of Northeastern and Southern Thailand, respectively. Two new species resemble M. woni in both sexes, but they are easily distinguished from their Cambodian relative by having: 1) transverse suture on the dorsal surface of the genital double-somite, 2) serrated hyaline frill on the posterior margin of third pedigerous somite, 3) different length / width ratio of caudal ramus, and 4) a row of spinule on caudal surface of intercoxal sclerite of the third swimming legs. The significant differences between M. sakaeratensis sp. nov. and M. brancelji sp. nov. are present in both sexes, including the body size, integumental ornamentation of the body surface, length / width ratio of caudal ramus, armature of the fifth swimming leg, and the male sixth swimming leg. In addition, an up-to-date key to the female of all fifteen species of Metacyclops recorded in Asia is provided.

The genus Cletocamptus (Harpacticoida, Canthocamptidae): a reappraisal, with proposal of a new subfamily, a new genus, and a new species

A new species of Cletocamptus closely related to C. helobius was found in sediment samples taken from a polluted estuarine system in north-western Mexico. The genus Cletocamptus was relegated to species incertae sedis in 1986, and this finding prompted us to evaluate the current taxonomic position of the genus within the Canthocamptidae. The latter has been subdivided in several, seemingly unnatural subfamilies in the past to better understand the relationships between its constituent taxa. In this study we propose a new subfamily, the Cletocamptinaesubfam. nov. for Amphibiperita, Cletocamptus, and Cletocamptoides gen. nov., defined by the synapomorphic subdistal ventral spinules on the rostrum. The genus Cletocamptoidesgen. nov. is proposed for C. helobius, C. merbokensis, and C. biushelosp. nov., and is supported by the ‘cletodid’ shape of the body and the reduced one-segmented endopod of the fourth swimming leg. Cletocamptus includes all the other species with long slender spinules on the posterior margin of prosomites and with the sexually modified inner spine on the second endopodal segment of the second swimming leg in the males. Amphibiperita retained the primitive female fifth leg with exopod and baseoendopod separated, and the primitive prehensile endopod of the first leg, but is defined by the loss of the antennary exopod. Other (syn)apomorphies are given, and the evolution of the mandibular palp is briefly discussed. Additionally, a diagnosis for the new subfamily, Cletocamptinaesubfam. nov., an amended narrower diagnosis for Cletocamptus, the diagnosis for Cletocamptoidesgen. nov., and a phylogenetic analysis supporting the proposal of these new taxa, are given.

On some deep-sea Stenheliinae from the Gulf of California and the west coast of the Baja California Peninsula (Mexico): the genus Delavalia Brady, 1869 and proposal of Archaeohuysia gen. nov. and Diarthropodella gen. nov. (Copepoda: Harpacticoida: Miraciidae)

Several species belonging to the harpacticoid families Ameiridae Boeck, Ancorabolidae Sars, Argestidae Por, and Rhizothrichidae Por have been described so far as an ongoing long-term project on the diversity of deep-sea benthic harpacticoids collected from the Gulf of California and Mexican Pacific. Amongst the several harpacticoid taxa, the subfamily Stenheliinae Brady (Miraciidae Dana) showed to be one of the most important components to overall species richness in deep-sea sediments. Following the rejection of segmentation pattern of the first swimming leg as the only discriminant for subgeneric assignment of stenheliin taxa, four new species of Delavalia Brady, 1869 and two new genera, Archaeohuysia gen. nov. and Diarthropodella gen. nov. are proposed herein. The new Delavalia species belong to the longicaudata-group with close relatives in shallow-water habitats. The so far monotypic Archaeohuysia gen. nov. showed to be unique in the combination of the general structure of the first swimming leg and retention of the primitive complement of four setae on the second endopodal segment of the same leg. Diarthropodella gen. nov. is the only stenheliin taxon with a two-segmented exopod of the first swimming leg. Some comments are given on probable multiple colonization events of stenheliin taxa.

A new species of Paralaophonte Lang 1948 (Harpacticoida: Laophontidae), with notes on the phylogeny of the genus and its relationships with Loureirophonte Jakobi 1953 using Bayesian inference

Early studies during the 1990’s supported a close relationship between the genera Paralaophonte and Loureirophonte. Subsequent studies carried out during the first decade of the 2000’s suggested the monophyly of the latter and that it could be nested within Paralaophonte, rendering the latter paraphyletic. However, efforts to synonymize these two genera were hampered by the lack of phylogenetic analyses at the species level. Here we describe a new species of Paralaophonte from north-western Mexico, P. ullama sp. nov., and we formally synonymize Loureirophonte with Paralaophonte for which we propose two monophyletic subgenera, Pa. (Paralaophonte) and Pa. (Loureirophonte). The detection of the species most closely related to P. ullama sp. nov. is controversial. Our Bayesian analysis indicates that the new species might be related to Pa. (Pa.) gurneyi, and to Pa. (Pa.) ormieresi and Pa. (Pa.) septemarticulata, with which they form a larger clade supported by a very low Bayesian Posterior Probability value. However, the precise nature of the relationship between the new species and Pa. (Pa.) gurneyi is hampered by the gap in our knowledge of the armature formulae of the swimming legs of the latter, and by the lack of the male of the new species. On the other hand, the new species share several characters with Pa. (Pa.) problematica, Pa. (Pa.) pacificavicinum, Pa. (Pa.) pacificaemulator, and Pa. (Pa.) pacifica, with which it might be related. Our Bayesian analysis of forty-two morphological characters at the species level confirmed earlier suspicions about the relationships between Paralaophonte and Loureirophonte, the latter being nested within the former, and showed the monophyly of the Paralaophonte-Loureirophonte clade with high Bayesian Posterior Probability value, thus confirming the synonymy of these genera. The Paralaophonte-Loureirophonte clade is defined by the synapomorphic dimorphism in the second endopodal segment of the second swimming leg of the male. We did not detect any (aut)apomorphy for Pa. (Paralaophonte). Paralaophonte (Loureirophonte) is defined by the presence of one seta only on the second endopodal segment of the second swimming leg, and the one-segmented endopod of the fourth swimming leg.

Quinquelaophonte enormis sp. nov., a new interstitial copepod (Harpacticoida: Laophontidae) from Korea

We collected an undescribed laophontid copepod from a coarse sand habitat on the east coast of Korea and named it Quinquelaophonte enormis sp. nov. We compared the detailed morphological characteristics of the new species with those of congeneric species. Among them, the new species shows a superficial resemblance to the Californian species Quinquelaophonte longifurcata Lang, 1965. However, the two species are easily distinguishable by the setation of the syncoxa on the maxilliped and the fourth swimming leg. The new species has the variable setation on the second to fourth swimming legs. The variations appear among individuals or between the left and right rami of a pair of legs in a single specimen. Although complex chaetotaxical polymorphism occur in this new species, we used myCOI and Cytb to confirm that the new species is not a species complex. Also, partial sequences of 18S and 28S ribosomal RNA genes were used to analyze the position of the new species within the family Laophontidae. The new speciesis the fourteenth Quinquelaophonte species in the world and the second species in Korea.

Restructuring the Ancorabolidae Sars (Copepoda, Harpacticoida) and Cletodidae T. Scott, with a new phylogenetic hypothesis regarding the relationships of the Laophontoidea T. Scott, Ancorabolidae and Cletodidae

Uncovering the systematics of CopepodaHarpacticoida, the second-most abundant component of the meiobenthos after Nematoda, is of major importance for any further research dedicated especially to ecological and biogeographical approaches. Based on the evolution of the podogennontan first swimming leg, a new phylogenetic concept of the Ancorabolidae Sars and Cletodidae T. Scott sensu Por (Copepoda, Harpacticoida) is presented, using morphological characteristics. It confirms the polyphyletic status of the Ancorabolidae and its subfamily Ancorabolinae Sars and the paraphyletic status of the subfamily Laophontodinae Lang. Moreover, it clarifies the phylogenetic relationships of the so far assigned members of the family. An exhaustive phylogenetic analysis was undertaken using 150 morphological characters, resulting in the establishment of a now well-justified monophylum Ancorabolidae. In that context, the Ancorabolus-lineage sensu Conroy-Dalton and Huys is elevated to sub-family rank. Furthermore, the membership of Ancorabolina George in a rearranged monophylum Laophontodinae is confirmed. Conversely, the Ceratonotus-group sensu Conroy-Dalton is transferred from the hitherto Ancorabolinae to the Cletodidae. Within these, the Ceratonotus-group and its hypothesised sister-group Cletodes Brady are combined to form a monophyletic subfamily Cletodinae T. Scott, subfam. nov. Consequently, it was necessary to restructure the Ancorabolidae, Ancorabolinae and Laophontodinae and extend the Cletodidae to include the displacement and exclusion of certain taxa. Moreover, comparison of the Ancorabolidae, Cletodidae, Laophontoidea and other Podogennonta shows that the Ancorabolidae and Cletodidae form sister-groups in a monophylum Cletodoidea Bowman and Abele, which similarly has a sister-group-relationship with the Laophontoidea T. Scott. According to the present study, both taxa constitute a derived monophylum within the Podogennonta Lang.

CASE OF SHRIMP PLEOPOD NECROSIS IN TRADITIONAL PONDS THAT APPLY PROBIOTICS

Traditional ponds fail in vanname shrimp farming due to disease. Disease causing pathogens can come from the culture environment, innate from shrimp seeds, and other inputs (introduction). Observation of shrimp health condition through detection of necrosis in swimming legs which, if left unchecked, will spread to the shrimp abdominal carapace, with the characteristics of the shrimp will look flushed by taking shrimp samples, and the results are expressed in percentage or prevalence. Symptoms of loss of swimming legs and uropod from the disease, of course, will reduce the selling value of the shrimp. The study was conducted on a traditional pond in Banyuanyara Village, Sanrobone District, Takalar Regency, South Sulawesi Province. Early cases of necrosis began to be detected at week 5th and peaked at week 8th. Vanname shrimp swimming leg necrosis in traditional ponds is significantly influenced by the number of bacteria in the water, where the more bacteria there are, the lower the prevalence of vanname shrimp swimming leg necrosis.

New species of Eurycletodes Sars, 1909 and Odiliacletodes Soyer, 1964 from the deep Gulf of California (Copepoda, Harpacticoida, Argestidae)

To date, three species of the family Ancorabolidae, three species of the family Argestidae, and one species of the family Rhizothrichidae are known from the deep sea of the Gulf of California. The descriptions of two new species,Eurycletodesparaephippigersp. n.andOdiliacletodessecundussp. n.collected from the Southern Trough of Guaymas Basin at 1440 m and 1642 m depths, respectively, are presented herein. The closest relatives of these two species,E.ephippigerPor, 1964 andO.gracilisSoyer, 1964 are known from the Mediterranean, but some relatives have been reported also from the southern Atlantic.Eurycletodesparaephippigersp. n.is undoubtedly related toE.ephippigerPor, 1964 known from Israel and Banyuls-sur-Mer (France). These two species can be separated by the armature complement of the basis of the maxillule, by the armature complement of the syncoxa of the maxilliped, and by the relative position of the anal operculum.Odiliacletodessecundussp. n.showed to be closely related toO.gracilisSoyer, 1964 known from Banyuls-sur-Mer only. The latter two species can be separated by the armature complement of the syncoxa of the maxilliped, by the structure of the antenna, and by the inner armature complement of the third exopodal segment of the fourth swimming leg.