First report of the genus Bicorniphontodes (Copepoda, Harpacticoida, Ancorabolidae) in South Korea, with descriptions of three new species

We report the occurrence of the genus Bicorniphontodes George, Glatzel & Schröder, 2019 in Korean waters, with descriptions of three new species: Bicorniphontodes lacuna sp. nov., B. comptus sp. nov., and B. huysi sp. nov. Morphology analysis was carried out to reconstruct the phylogenetic relationships of Bicorniphontodes species, including the three new species. Parsimony analysis based on 41 characters revealed that the three new species are clustered together as a monophyletic clade, of which B. horstgeorgei (George & Gheerardyn, 2015) is a sister species. The monophyletic status of three new species was supported by five synapomorphies, such as the micro-morphological conditions of the exopodal segments of the first leg, coxae of the second to fourth legs, exopod of the fifth leg in the female and baseoendopod of the fifth leg in the male, and the maxillular endopod represented by two setae. These three species can be easily distinguished based on the morphology of the rostrum, cephalothoracic processes, female genital double-somite, caudal rami, and second endopodal segment of the third leg in the male. The taxonomic position of B. bicornis sensu Kim, 2013 in Korean fauna was reevaluated based on the newly collected material from Udo Islet near Jeju Island; this resulted in a synonym of B. huysi sp. nov.

Two New Species of Parastenocaris (Copepoda, Harpacticoida) from a Hyporheic Zone and Overview of the Present Knowledge on Stygobiotic Copepoda in Vietnam

The number of freshwater species belonging to the genus Parastenocaris reported from ten countries of Southeast Asia is quite limited. Only two species have been reported so far from freshwater habitats there, compared to over 290 described species of the family Parastenocarididae worldwide. During the first study of the hyporheic zone of two small rivers in central Vietnam, two new species of the family Parastenocarididae were collected, Parastenocaris sontraensis sp. nov. and Parastencaris vugiaensis sp. nov. Both were collected from the gravel bar along the rivers (Suoi Da and Vu Gia river) using the Karaman–Chappuis method. Both the new species belong to the brevipes group of the genus Parastenocaris Kessler, 1913 sensu Lang (1948), and Reid (1995). Parastenocaris sontraensis sp. nov. is similar to P. hinumaensis Kikuchi, 1970 and Parastenocaris jane Karanovic, 2006 in the brevipes-group. Parastenocaris sontraensis sp. nov. differs from both Parastenocaris species by (i) Exp P3 with three segments in the male, (ii) caudal rami with seven setae, and (iii) caudal rami about 2.4 times as long as wide. Parastencaris vugiaensis sp. nov. can be distinguished from its congeners by the unique combination of the following characters: (i) the elliptical shape of caudal rami, (ii) apical seta (V) with bulbous base, and (iii) anal operculum extends beyond the end of anal somite. Until now, 14 stygobiotic species of Copepoda have been recorded in Vietnam (including two new species in this paper), which is relatively few compared with nearby Thailand with 25 species. Short comments on other stygobiotic Copepoda from Vietnam are added.

A new species of Maraenobiotus Mrázek, 1893 (Copepoda: Harpacticoida: Canthocamptidae) from Colombian Andean mosses, with an identification key for the American species

Maraenobiotus wellsi sp. nov. (Canthocamptidae) is described based on material collected in mosses in the “páramo” region of the Andean Cordillera of Colombia. The new species is closely related to M. australis Apostolov, 2001 from Tierra de Fuego in Argentina, but can be distiguished by the shape of the caudal rami, the insertion point of its terminal seta IV, and the chaetotaxy of distal segments of legs 3 and 4. We discuss morphological differences with other congeners inhabiting South America (Peru), i.e. M. naticochensis Delachaux, 1917, M. fontinalis Harding, 1955 and M. fontinaloides Löffler, 1960. Major distinguishing features were observed in the chaetotaxy of legs 2 and 3, the morphology and size of the caudal rami, and the ornamentation of the anal operculum. We also discuss morphological characters that distinguish the new species from those living exclusively in mosses, such as M. cuspidatus Štěrba, 1968 and M. canadensis Flössner, 1992, and those reported from mosses and other habitats i.e.. M. vejdovskyi Mrázek, 1893, M. brucei brucei (Richard, 1898), M. zschokkei Kreis, 1920, M. brucei himalayensis Chappuis, 1928b, M. truncatus (Gurney, 1932), M. insignipes elgonensis Chappuis, 1936, M. insignipes nepalensis Löffler, 1968 and M. kinabaluensis Löffler, 1973. A distribution map of American species and an identification key for females are provided.

Interesting interstitial Paramesochridae (Copepoda: Harpacticoida): Maliithipon wellsi gen. et sp. nov. from the Philippines, M. aberrans (Mielke, 1984) comb. nov. from Panama, and M. cf. aberrans (Mielke, 1984) from the Azores

We propose and describe a new genus of interstitial Paramesochridae, Maliithipon gen. nov., to accommodate three species. Maliithipon wellsi sp. nov., type species of the genus, is described based on specimens collected in two sandy beaches in Isla Verde, the Philippines. Apodopsyllus aberrans Mielke, 1984a described from Panama, is allocated to the herein erected genus as Maliithipon aberrans (Mielke, 1984a) comb. nov. Maliithipon cf. aberrans is described, based on specimens collected in the Azores and previously identified as Apodopsyllus aberrans. The new genus is characterized by several distinct morphological features: mandible with uniramous, 2-segmented palp and gnathobase with thin and pointed teeth; maxillule with reduced armature, lacking endopod and exopod; maxilla large, with three syncoxal endites and endopod with reduced setal number; P5 very reduced in both sexes; caudal rami with six setae, two of which (setae III and VI) transformed; pseudoperculum well-developed, with four-lobed distal margin. The new genus is included in the subfamily Paramesochrinae Lang, 1944 and in the genus-group Scottopsyllus (sensu Huys, 1987). It has strong affinities with Leptopsyllus (Leptopsyllus) platyspinosus Mielke, 1984b and Wellsopsyllus (Intermediopsyllus) smirnovi (Kunz, 1992), which are considered as species inquirendae in this paper. Some remarks on the ecology and geonemy of the three studied species are provided. We also list the accompanying Paramesochridae obtained from the two new collecting sites of the genus, and all the genera of Paramesochridae recorded from other sites in the Philippines during the same survey.

New species of Elaphoidella Chappuis, 1929 and Schizopera Sars, 1905 (Copepoda: Harpacticoida) from two caves in northeastern and southern Thailand

Two new copepod species from two caves in northeastern and southern Thailand are described. Elaphoidella isana sp. nov. and Schizopera paktaii sp. nov. were collected from the unsaturated zone of freshwater pools fed only by dripping water. They are closely related to E. intermedia Chappuis, 1931 and S. validior Sars, 1909, respectively. Elaphoidella isana sp. nov. can be distinguished from its closest relative by the armature of P4 and P5, and by the ornamentation of caudal rami. Schizopera paktaii sp. nov. differs from its relative S. validior in the armature of P1, P5 and caudal rami.

The genus Stammericaris Jakobi (Copepoda: Harpacticoida: Parastenocarididae) in the Nearctic subregion: description of Stammericaris remotaepatriae sp. nov., proposal of Stammericaris palmerae (Reid 1992) comb. nov., and remarks on other North American Parastenocarididae

We describe a new harpacticoid, Stammericaris remotaepatriae sp. nov., collected from the hyporheic habitat of a stream in Nantucket, MA, USA. The new species is characterized by the size of the caudal rami of both sexes, which are shorter than the anal somite, by the morphology and armature of the P3 and, mainly, by the P4 endopod of males, represented by a curved plate with a strongly bifid tip, the distal proximal outgrowth of the distal margin spiniform and denticled, the proximal outgrowth missing. The study of the new species allowed us to review the systematic position of Parastenocaris palmerae Reid, 1992, which we transferred to Stammericaris Jakobi, 1972 as Stammericaris palmerae (Reid, 1992) comb. nov., based mainly on the structure of the male P4 endopod complex and the setation of the caudal rami. We also discussed the taxonomic position and affinities of Parastenocaris trichelata Reid, 1955, suggesting that this species is related to the two former ones for a set of diagnostic features, but can not be attributed to the genus due to the peculiar morphology of the male P4 endopod complex; P. trichelata is therefore considered species inquirenda. We also discussed Parastenocaris sp. 1 and Parastenocaris sp. 3, two taxa only partially described and drawn in Strayer (1988). In fact, Parastenocaris sp. 1 can be related to Stammericaris and might represent a third species of the genus in the Nearctic region. Remarkably, the structure of the male P4 endopod of Parastenocaris sp. 3 is typical of Proserpinicaris Jakobi, 1972; this hypothetical assignment of the species to Proserpinicaris, if confirmed, would be of relevant taxonomic and biogeographic value. Finally, we provide an updated distribution map of the genus Stammericaris and brief remarks on the faunistic and ecological characteristics of the taxa presented and discussed in this paper.

A new species of Pilarella (Copepoda, Calanoida, Arietellidae) from the hyperbenthic layer of Japan, with a molecular phylogenetic analysis of some representative genera of the Arietellidae

A new species of the continental shelf hyperbenthic genus Pilarella is described, the first from the Indo-Pacific. This is the second species of Pilarella known, and the first description of a male in the genus. The new species is easily distinguished from other species of Pilarella (P. longicornis) based on: (1) short caudal rami, approximately 1.5 times longer than wide; (2) 2 setae on the mandibular endopod; (3) 6 setae on the maxillular coxal epipodite; and (4) in the female, a short left antennule reaching the posterior border of the genital double-somite. The new diagnosis of Pilarella differs from Metacalanus in the separation of ancestral segments IX–XII and XIV–XV of the antennule, and the presence of 5–6 setae on the maxillular praecoxal arthrite. Pilarella is also separated from Metacalanalis based on the absence of a seta on the third ancestral segment of the antennary exopod, the symmetry of legs 1–3, the presence of a medial basal seta on the female leg 5, and 2 lateral exopodal spines on the female leg 5. A molecular phylogenetic analysis of some representative genera of the family Arietellidae, including the present new species, recovers two arietellid clades (Metacalanus- and Arietellus-clades) as in previous studies. Dichotomous keys for the genera of Arietellidae and the species of Pilarella are included.

Review of the genus Haloschizopera (Harpacticoida: Miraciidae, Diosaccinae) with description of a new species

Haloschizopera cheni sp. n., was recognized from our latest collections from the East China Sea. The new species is similar to H. abyssi Becher, 1974 but differs from it by the following combined features: baseoendopodal lobe of female P5 with five setae, P2 and P3 enp-3 both longer than enp-1-2 combined, and caudal rami longer than broad. Comparison of all the known species of Haloschizopera was performed. Species in the genus can be divided into four groups by the setal formulae of P3 and P4. The main diagnostic characters of each species are listed and a key to all known species of Haloschizopera is also provided.

Morphometric study of certain inland water copepods from Nashik, Maharashtra, India

The morphometric study of selected copepods was carried out during year 2018 from Godavari river of Nashik region. In the present study, a total of four copepod genera were selected for carrying out their morphometric measurements in terms of micron. These are Mesocyclops sps, Macrocyclops fuscus, Tropocyclops prasinus and Eucyclops agilis. The morphometry of various body parts like cephalosome, metasome, urosome, antennae, caudal rami, fural rami and total body length were measured by using ocular micrometer scale. On the basis of measurement obtained in the present study, it can be concluded that Eucyclops is the largest of all, Macrocyclops and Tropocyclops are intermediate in size whereas, Mesocyclops is the smallest of all studied specimens.

A new species of Pseudovaigamus Amado, Ho & Rocha, 1984 (Cyclopoida: Ergasilidae) from the teleost Pimelodus maculatus Lacepède, 1803

A new species of the copepod genus Pseudovaigamus Amado, Ho & Rocha, 1984 is described herein based on parasitic adult females found attached to the gills of the freshwater teleost Pimelodus maculatus Lacepède, 1803, sampled in two tributaries (Veados and Paranapananema Rivers) of the Jurumirim Reservoir, Upper Paranapanema River, São Paulo State, Brazil. The new copepod was identified as an undescribed species of Pseudovaigamus because it shares with the type-species, Pseudovaigamus spinicephalus (Thatcher & Robertson, 1984), the combination of first leg with 2-segmented endopod, fourth leg with 3-segmented endopod and 2-segmented exopod, and cephalothorax armed with dorsolateral stylets (or retrostylets). However, the new copepod differs from its congener in having a trifid rostral spine, retrostylets with long spatulate process, 5-segmented antennule, and caudal rami simple or lacking any distal lobe. We erected a new species, Pseudovaigamus tridentatus n. sp.. It is the first report of a Pseudovaigamus found on a freshwater fish in Brazil.