Ameiridae Boeck and Argestidae Por revisited, with establishment of Parameiropsidae, a new family of Harpacticoida (Crustacea, Copepoda) from deep-sea sediments

Four new species of Parameiropsis are described from Angola and Guinea Basins and the Arctic Laptev Sea. The male of Parameiropsis poseidonicus sp. n. differs from that of P. neptuni sp. n. and P. senckenbergi sp. n. in antennule segmentation, length of the proximal aesthetasc, length of the outermost seta of the antennary endopod, degree of reduction of the mouthparts, relative length of the inner spine of the basis of thoracopod 1, shape of the furca and body length. The female of P. amphitriteae sp. n. differs from previously described females of other species in the smaller exopod and endpod of thoracopod 1, reduced armature of thoracopods 1–6, length of the outer setae of exopods and endopods of thoracopods 2–4, and mandible exopod weakly developed and fused to the basis. Parameiropsis is redefined by the following autapomorphies: presence of aesthetasc on 3rd segment of female antennule; antenna strong, with endopod curved upwardly, and shape of the outermost (strongly ornamented) spine; triangular labrum; elongated corpus mandibularis, gnathobasis very long; basis of mandibular palp unarmed; elongated maxillule, with long and flexible setae on praecoxal arthrite; basis of the maxilla with strongly modified claw. To discuss the phylogenetic position of Parameiropsis, we revaluated the subfamilies of Ameiridae (viz. Ameirinae and Stenocopiinae) and the family Argestidae. Anoplosomella and Malacopsyllus revealed to be not closely related to Ameiridae and are transferred to Argestidae, sharing with other members of this family the morphology of the mandible gnathobasis, armature of maxilla and armature and length of the first segment of the antennule. Argestoides prehensilis does not show any of the characters that we consider autapomorphic for Argestidae. Instead, it shows many characters in common with several Ameiridae species. Parameiropsis does not have any character that could justify its inclusion within Ameiridae or even within Podogennonta. It also cannot be included satisfactorily within Argestidae nor Exanechentera. Therefore, we here propose a new family for Parameiropsis, with unclear relationships within Harpacticoida. After these taxonomic rearrangements, Ameiridae and Argestidae are considered monophyletic based on certain maxilla characters that we consider autapomorphic for each group. A key to the identification of the known species of Parameiropsis is added at the end.     

Review of naupliar development among Miraciidae (Copepoda,Harpacticoida) with a naupliar description of <Emphasis Type="Italic">Paramphiascella</Emphasis><Emphasis Type="Italic">choi</Emphasis> sp. nov. from Thailand

Both genders of Paramphiascella choi sp. nov. were collected from the green alga Enteromorpha clathrata in Rayong province, Thailand. P. choi shares with other species of the genus: cylindrical body shape, rostrum not bifid, eight-segmented antennules, three-segmented exopodal antenna, and female P5 exopod with five setae. The new species distinguished from other conspecific species by: three-segmented exopodal antenna, inner edge of basis of male P1 and P2 bear a bare ovate-knob each. Enp-1 very elongate, Enp-2 of male P2 transformed into a large, strong, slightly curved and tapering attenuation with two central chitinous ridges, and bearing one medially directed knob close to enp-1. At the base of this knob arise three plumose setae of unequal length. These characters are suggested to be autapomorphies of the new species. Six naupliar stages are obtained and described a key for the identification of stages is provided. Nauplius I has one pair of caudal setae; three-segmented antennules; antenna consists of a coxa, basis, endopod and exopod; mandible has a coxa, basis, endopod and exopod; hindbody bears two caudal setae. Nauplius II develops one aesthetasc on the antennule; antenna has added an arthrite arising from the coxa; mandible has a row of tiny spinulose setae. Nauplius III has added two pairs of caudal setae. Nauplius IV bears bilobed bud of the maxillule armed with two setae and four pairs of caudal setae. Nauplius V bears a multilobed bud of the maxillule with three setae and five pairs of caudal setae. At Nauplius VI, the buds of swimming legs 1 and 2 are added.     

The life-cycle of Ergasilus briani Markewitsch, 1993 (Copepoda: Poecilostomatoida)

The life cycle of Ergasilus briani is shown to consist of six nauplius stages, five copepodid stages and the adults. Only the adult female is parasitic. The free-living stages are described in detail. The presence of three aesthetascs on the antennules of all copepodid stages and the adult is noted for the first time. Unusual aspects of E. briani development include: the antennule is sexually dimorphic from copepodid IV onwards, the dimorphism being expressed in the numbers of setae present on the more proximal segments, and the first appearance of the male maxilliped is at the copepodid II stage. The endopodal setation of the male maxilliped is the maximum known within the Poecilostomatoida. The striking pigmentation of the developmental stages of ergasilids is noted and discussed.     

Psammic Procyclopina (Copepoda, Cyclopoida) from the coast of Brazil

Procyclopina polyarthra Herbst is redescribed and three new species, P. maricopeba, P. feiticeira and P. uguaipuku , are described from intertidal interstitial waters. Procyclopina is distinguished within the family by the enditic setation of the maxilliped 0,1,3,4, the 19-segmented antennule, and three elements in the leg 5 exopod of the female. Procyclopina has its distribution restricted to the coast of Säo Paulo, Brazil. Procyclopina maricopeba sp. n. is distinguished from P. polyarthra by the three-segmented leg 5 in the male and by the length: width ratio of the genital double somite in the female. Procyclopina feiticeira sp. n. is unique in the genus by lacking the inner seta on legs 14 exp-I, and by the incomplete fusion of genital (seventh thoracic) and first abdominal somites in the female. Procyclopina uguaipuku sp. n. is characterized by the antennulary armature, by the caudal ramus (much longer than wide), and by the position of the proximal seta of the leg 4 enp-2 which is set on a protuberance on the posterior face. Morphological characters of Procyclopina are compared with those of other cyclopinids.     

A new species of Neocervinia (Copepoda: Harpacticoida: Cerviniidae) from the hyperbenthos of the Hatsushima cold-seep site in Sagami Bay, Japan

A new species of harpacticoid copepod, Neocervinia itoi (Cerviniidae), is described on the basis of females and copepodids collected from the Hatsushima cold-seep site in Sagami Bay, Japan. It is morphologically very close to its deep-sea congeners N. tenuicauda (Brotskaya, 1963) and N. unisetosa (Montagna, 1981). The new species differs primarily in the segmentation of the antennule and the endopod of both mandible and maxilliped, and in form and shape of the setae on leg 5. The presence of sensillar structures on the proximal part of the antennule is discussed. A key to the species of Neocervinia is presented. This revised version was published online in July 2006 with corrections to the Cover Date.     

Two morpho-types of Botryllophilus (Cyclopoida,Ascidicolidae)

In taxonomic studies (in preparation) of the genus Botryllophilus from the eastern and western coastal waters of the Pacific and from the northern Gulf of California, we have found that the females are morphologically divided into 2 types. The 2 morpho-types in our material, which includes 10 species, are characterized by features of the urosome including anal segment and caudal rami, rostrum, antennule, antenna, mandible, maxillule, maxilla, maxilliped, 1st to 5th legs, and the apparatus at the oviducal aperture. These characters are described and the significance of the recognition of the 2 morpho-types is discussed for the purpose of solving taxonomic problems in Botryllophilus.     

Boeckella diamantina n.sp. (Calanoida,Centropagidae), from a high Andean lake in Mendoza,Argentina

A new species of Boeckella from limnetic samples of Laguna del Diamante, a high lake in the Andes (34°10 S) is described and illustrated. The species is defined by the characters of the male fifth leg: the right two segmented endopod bears four peculiar, short, claw-like spines, the left endopod is a simple finger-like projection. This species is related to B. gibbosa, also a species from the Andes and B. vallentini from Malvinas (Falkland Islands) and other subantarctic islands. It is distinguished from them by diagnostic features of the fifth legs of the male and abdominal structure and fifth legs of the female. Some current views on the features used in the taxonomy of the genus Boeckella are discussed.     

<Emphasis Type="Italic">Foxtosognus rarus</Emphasis> gen. n., sp. n.—A new genus and species of copepods (Copepoda: Calanoida) from the abyssopelagic zone of the Kuril-Kamchatka Trench

A female of Foxtosognus rarus gen. n., sp. n., a new genus and species of copepods, is described from the abyss of the Kuril-Kamchatka Trench. The new genus is placed in the family Arctokonstantinidae, whose diagnosis is emended and supplemented with the following characters: mandibular basis with one to two setae; mandibular endopod one without setae; maxillular distal basal endite plus endopod with two to four setae or without setae. The features that distinguish Foxtosognusgen. n. from other representatives of this family are as follows: mandibular palp with a long endopod segment one, endopod segment two with seven setae, and exopod segment five with two setae; maxillula with distal basal endite lacking setae and separated from endopod bearing three setae; maxillular precoxal arthrite with seven to eight setae and exopod with four setae; maxilliped syncoxa without setae on precoxal endites and endopod of three segments. The genera Sognocalanus and Foxtonia earlier included in the Spinocalanidae are herein transferred to the Arctokonstantinidae.     

A new genus (Copepoda,Harpacticoida, Laophontidae) from Jeju Island of Korea

A survey on the harpacticoid copepods from an intertidal zone in Hyeopjae sandy beach, Jeju Island, Korea, resulted in the discovery of an unusual laophontid, Jejulaophonte hyeopjaeensis sp. n., which cannot be placed in any extant genus within the family. To accommodate the species, a new genus of the family Laophontidae T. Scott, 1905 is proposed and fully described here. The new species is closely related to the lineage of the five primitive genera, Carraroenia McCormack, 2006, Coullia Hamond, 1973, Hemilaophonte Jakubisiak 1933, Psammoplatypus Lee & Huys, 1999, and Robustunguis Fiers, 1992 (the CCHPR-lineage) by the reduced P2 endopod, ovate shape of the female P5 exopod and sexual dimorphism in the P3 endopod. However, it displays discrepancies from the species of the CCHPR-lineage in the presence of an inner seta on P3 and P4 exp-2, four setae on P4 enp-2, and an inner seta on P3 and P4 enp-2 in the female. Furthermore, no other species within the family Laophontidae has three setae on P2 exp-3 and a seta on P2 enp-2 at the same time. The new species has sexual dimorphism in the antennule, genital segmentation and the legs from P2 to P5. The terminal seta on the second endopodal segment of P2 in the male is longer than that in the female. The endopod of P3 is 3-segmented and displays a short inner apophysis on the second segment in the male. The outer setae on the exopod of P3 and P4 are distinctly thicker and stronger in the male than in the female. Mitochondrial cytochrome oxidase subunit I (mtCOI) sequencing of the new species has been realized in order to be used in future phylogenetic analysis.     

New Harpacticoida (Crustacea, Copepoda) from the North Atlantic Ocean. VIII. The description of Eurycletodes (Oligocletodes) quadrispinosa sp.n. and the male of E. (O.) monardi Smirnov (Cletodidae)

Eurycletodes (O.) quadrispinosa Sp.n. and the male of Eurycletodes (O.) monardi are described. E. quadrispinosa differs from the closely related species E. echinatus Lang, E. parasimilis Por and E. arcticus Lang in the setation of segment 1 and 2 Exp P2–P4, of segment 2 Exp p24 and of the Exp P5. Because of the same setation of the A2, Pl-P4 Exp and Exp as the female of E. monardi Smirnov the described male is regarded as that of E. monardi Smirnov. The species were collected at the Iceland Faroe Ridge from depths of 500. 1540 and 2500 m.     

Cyclopina (Copepoda, Cyclopoida) from Brazilian sandy beaches

Five new species of Cyclopina Claus are described and C. mediterranea Steuer is redescribed from Brazilian sandy beaches. Cyclopina curoli sp. n. can be very abundant in coarse sandy shows. It is related to C. laurentica Mocholls and C. crassisserosa Herbst with which it shares a similar structure of Leg 5 in the female. Cyclopina dorae sp. n. is most closely related to C. meditarranea Steuer. Cyclopina arenosa sp. n. and Cyclopina yutimaete sp. n. are reminiscent of C. pontica Monchenko, the only other species of Cyclopina that possess a 2-segmented endopod in leg 1. Cyclopina caissara sp. n. is distinguished from all other congeneric species by having a very reduced inner spine in the leg 5 exopod of both male and female. This species shares with C. schneideri Scott and C. schneideri and C. brevifurca Sars the 12–segmented antennule. Taxonomical problems related to C. schneideri and C. brevifurea are discussed. Cyclopina mediterranea Steuer, 1940 is recorded for the first time from the American continent.     

Mospicalanus schielae,a new genus and species of calanoid copepod (Crustacea: Spinocalanidae) from deep Antarctic water

A new genus and species,Mospicalanus schielae, collected at bathypelagic depth in the Antarctic Ocean, is described from female specimens and a stage V male. The new species is placed in the Spinecalanidae on account of the absence of fifth legs and leg 1 characteristics. It appears to be closely related toMimocalanus Farran. 1908, sharing apomorphic characters such as the lack of a rostrum, reductions of setal armament on the mouthparts, and absence of an outer spine on the first exopod segment of leg 1.Mospicalanus schielae can be distinguished from other spinocalanid genera by the setation of the antennary exopod, the maxillule, and the paecoxal endite of maxilla. Diagnostic characters of Spinocalanidae and Bathypontiidae are also discussed in order to clarify affiliation of genera tentatively assigned to the latter family. An updated key is given for the spinocalanid genera.     

How many species of Diacyclops? New taxonomic characters and species richness in a freshwater cyclopid genus (Copepoda,Cyclopoida)

The genus Diacyclops Kiefer, 1927 emend. Morton (1985) includes more than 100 species, widely distributed in all kinds of freshwater environments, and is the richest genus in the family Cyclopidae. Traditionally, Diacyclops species were defined according to differences in a few morphological characters; some characters (number of antennulary segments, segmentation pattern of swimming legs) are useful only in the separation of species groups, others (length of caudal rami and caudal setae) are highly variable even within the same population. During the study of the D. languidoides-group, minute morphological characters were used to differentiate between species (spinulation pattern and setation of antennary basis, setation and aesthetasc shape of male antennule, setation of mandibulary palp and maxilliped, shape of leg 4 basis) which allow to identify several valid species up to now concealed under the name `Diacyclops languidoides' (Lilljeborg, 1901). The coexistence of up to six congeneric species in the same sampling area: (a) supports the validity of the proposed taxonomic characters, (b) demonstrates that species richness may be highly underestimated in freshwater cyclopoid assemblages in absence of good taxonomic practice; and (c) requires an ecological explanation of species coexistence. The role of morphologically based taxonomy in order to solve general problems of distributional ecology and theoretical biology is explored.     

Redescription of Mesocyclops aspericornis (Daday, 1906) (Copepoda: Cyclopoida) from an Indian pond

The morphology of a cyclopoid copepod, Mesocyclops aspericornis(Daday, 1906), from a tropical pond is redescribed in detail.This species is clearly distinguished from Mesocyclops leuckarti.New diagnostic characters, such as the distribution of featheredand non-feathered outgrowths on the antennule, the presenceof aesthetascs in both genders, circular groups of spinulesalong the dorsal and ventral surface of caudal rami, a groupof 14 spinules on the coxa of P2 and P3 and eight spinules onP1 and P4, are described. In the case of males, a stouter firstendopodite segment of the antennae and an upwardly bent spineon the first exopodite segment of P2 and spinules on the genitalsegment are described for the first time. The taxonomy of M.aspericornis is discussed.     

Taxonomic studies on Danielssenia (Crustacea, Copepoda, Harpacticoida) with descriptions of two new species from Norway and Alaska

As a result of an examination of the original material of G. O. Sars and of new material from Björnehodebukta, Oslofjord, Danielssenia fusiformis (Brady) is synonymized with Danielssenia typica Boeck and the latter species redescribed. Two new species are described; D. quadriseta , from Oslofjord, is distinguished from all other known species by the presence of only 1 inner seta on the distal endopodite segment of swimming leg 3; Danielssenia reducta , from Alaska, is the only species in the genus with just 3 setae on the terminal endopodite segment of swimming leg 4. A new key to species of Danielssenia is also provided.     

A new species ofXantharus Andronov, 1981 (Copepoda: Calanoida) from the mesopelagic zone of the Antarctic Ocean

Xantharus renatehaassae sp. nov. is described from a female taken at mesopelagic depth of the Antarctic Sound. This is the second species within the genus to be described and the first record ofXantharus in the southern hemisphere. A diagnosis of the genus is presented. Primarily, the structure of the maxillar aesthetascs showed thatXantharus belongs to the Scolecitrichidae, and not to the Phaennidae as was originally proposed. Its most outstanding generic feature relates to the structure of the distal segments of the short antennule with some plesiomorphic conditions retained by particular mouthparts.     

Platycopia compacta n. sp., the Second Species of Platycopioida (Crustacea: Copepoda) in the Indo-Pacific Region, with Remarks on Development, Feeding, Swimming, and Zoogeography

Platycopia compacta new species (Copepoda: Platycopioida) is described from the hyperbenthic zone in the Tokara Islands, southern Japan. This is the second species of the order in the Indo-Pacific region, and the eighth species of the genus. The present new species is distinguishable from the closely related P. inornata from the Bahamas by (1) the formation of allobasis in the antenna; (2) two unequal setae on the basal exite of the maxillule; (3) the intermaxillipedal process with only 3 pairs of prominences at tip; (4) the fusion of the coxa and basis in leg 3; and (5) the fusion of the second and third endopod segments in female legs 3-5. Copepodid stages III, V, and VI are compared with those of P. orientalis collected from Okinawa, and differ in the developmental patterns of the antennule and legs. The presence of an intermaxillipedal process and gut content analysis revealed that Platycopia is carnivorous. The armature of legs 2-5 of the hyperbenthic genus Platycopia is stouter than that of cavernicolous platycopioids, which indicates that Platycopia may penetrate into loose sediment, whereas the latter group might be more adapted to pelagic life. The horizontal distribution of the genus Platycopia apparently exhibits a full Tethyan track.     

Gauchergasilus,a new genus for Ergasilus euripedesi Montú, 1980, an abundant parasitic copepod from the Patos Lagoon in southern Brazil

Ergasilus euripedesi is redescribed from newly collected material of both sexes. A new genus, Gauchergasilus, is proposed, with Gauchergasilus euripedesi n. comb., formerly Ergasilus euripedsi Montú, 1980, as its type and only species. The new genus is characterised principally by the five-segmented antennule, the presence of a conspicuous barb on the concave margin of the claw of the antenna, the two-segmented endopod of leg 1 and the reduced fifth leg comprising two setae, one papillate. The male lacks the barb on the antennal claw but its other appendages are similar to those of the female, except for the maxilliped which is absent in females. The affinities of the new genus lie with the Acusicola group of genera.