Revision of the systematic position of Eucyclops bathanalicola Boxshall et Strong, 2004, with the description of Boxshallianus gen.n. and Boxshallianidae fam.n.

The occurrence, prevalence and infection intensity of proteocephalidean larvae in naturally infected intermediate hosts of the Upper Paran River floodplain are reported. A total of 5,206 zooplanktonic and benthic organisms were analyzed, namely cyclopid (2,621) and calanoid (1,479) copepods, cladocerans (704), rotifers (307), chironomid larvae (41) and ostracods (54). Eight cyclopid copepods - two copepodids, one male and five females - comprising 0.3% of the cyclopid copepods examined, were naturally infected. The male infected belonged to a species of Paracyclops, and the females to Paracyclops sp., Thermocyclops minutus and Mesocyclops longisetus.

Plankton samples obtained from the Ciénaga Grande de Santa Marta, an extensive estuarine system in northern Colombia, yielded adult male and female specimens of an undescribed halicyclopine cyclopid copepod of the genus Halicyclops. Cyclopid copepods are frequently found in freshwater and transitional habitats. Members of the subfamily Halicyclopinae are chiefly brackish water forms with a few freshwater species. The new species described herein is assignable to the group of species “F” of Halicyclops (sensu Pesce, 2018) with a 2333 exopodal spine formula. Currently, this group contains five species and one subspecies. Halicyclops gutierrezi sp. n. can be distinguished from its known congeners by the absence of an anal operculum, the relative length of setae of the female and male P5, the relative length of the inner setae of P4EXP3, and details of the male antennule. This is the fifth species of Halicyclops recorded from Colombia and the first one of Halicyclops group “F” described from the Caribbean region. With the addition of H. gutierrezi sp. n., the number of species of the genus known from the Neotropics increased to 20. A key to the species of the genus recorded in Colombia is also provided.

Cyclopid copepods are known to be good mosquito controllers, specially as regards the larvae of the dengue vectors Aedes aegypti and Ae. albopictus. The objective of the study was to survey the local copepod fauna and search for new strains of M. longisetus var. longisetus, comparing the potential of the samples found with the current strain ML-01 against Ae. albopictus larvae, under laboratory conditions. Eleven bodies of water in Campinas, SP, Brazil, were screened for copepods by collecting 1.5 l of water from each of then. The predatory potential of adults copepods was evaluated over 24 h, in the laboratory, for groups of 5 individuals preying upon 30 first instar Ae. albopictus larvae. The following cyclopid species were found: Metacyclops mendocinus, Tropocyclops prasinus, Eucyclops sp, Eucyclops serrulatus, Eucyclops solitarius, Eucyclops ensifer, Macrocyclops albidus var. albidus and Mesocyclops longisetus var. longisetus. The predatory potential of these copepods ranged from nil to 97.3%. A sample collected in the field containing only M. longisetus var. longisetus showed the best control efficiency with no significant difference from a three-year old laboratory culture (ML-01) of the same species evaluated for comparison. The sample with few M. albidus var. albidus was ranked in second place showing an average 25.9% efficiency. The use of copepods in trap tires as dengue vector controllers is discussed.

The life cycles of species of Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidea) parasitizing fishes in the Palearctic Region are reviewed on the basis of literary data and personal experimental observations, with special attention being paid to the development within the intermediate and definitive hosts. Planktonic crustaceans, diaptomid or cyclopid copepods (Copepoda), serve as the only intermediate hosts of all Proteocephalus species considered. A metacestode, or procercoid, develops in the body cavity of these planktonic crustaceans and the definitive host, a fish, becomes infected directly after consuming them. No previous reports of the parenteral location of metacestodes within the second intermediate host as it is in the Nearctic species P. ambloplitis have been recorded. Thus, the life cycles of Proteocephalus tapeworms resemble in their general patterns those of some pseudophyllidean cestodes such as Eubothrium or Bothriocephalus, differing from the latter in the presence of a floating eggs instead of possessing an operculate egg from which a ciliated, freely swimming larva, a coracidium, is liberated. The scolex of Proteocephalus is already formed at the stage of the procercoid within the copepod intermediate host; in this feature, proteocephalideans resemble caryophyllidean rather than pseudophyllidean cestodes. The morphology of procercoids of individual species is described with respect to the possibility of their differentiation and data on the spectrum of intermediate hosts are summarized. Procercoids of most taxa have a cercomer, which does not contain embryonic hooks in contrast to most pseudophyllidean cestodes. The role of invertebrates (alder-fly larvae — Megaloptera) and small prey fishes feeding upon plankton in the transmission of Proteocephalus tapeworms still remains unclear but these hosts are likely to occur in the life cycle. Data on the establishment of procercoids in definitive hosts, morphogenesis of tapeworms within fish hosts, and the length of the prepatent period are still scarce and new observations are needed. Whereas extensive information exists on the development of P. longicollis (syns. P. exiguus and P. neglectus), almost no data are available on the ontogeny of other taxa, in particular those occurring in brackish waters (P. gobiorum, P. tetrastomus). The morphology of P. cernuae and P. osculatus procercoids from experimentally infected intermediate hosts is described for the first time.

Some morphological characteristics of Cephalochlamys namaquensis from Xenopus muelleri collected at Kajansi, Kampala, are described.Specimens of cestodes from other localities in Africa are compared with those from Kajansi in order to assess the reliability of the characters of the proposed genus Pseudocephalochlamys Yamaguti, 1959. Reasons are given for rejecting the genus.The embryonated, non-operculate egg capsules hatch at once in water. The ciliated coracidium is eaten by cyclopid copepods and the oncosphere rapidly penetrates through the mid-gut wall into the haemocoel. The procercoid develops a cercomer which moves actively during development and which retains the six hooks of the oncosphere. The procercoid develops the scolex, osmoregulatory canals and calcareous corpuscles typical of the adult while within the copepod. It is enclosed within a membrane. The procercoid is infective to Xenopus toads 20 days after being ingested by the copepod. No other intermediate host has been found.Thermocyclops infrequens Kiefer is the intermediate host at Kajansi, Kampala. The maximum number of C. namaquensis recovered from one toad was 103; usually there are between 1 and 6 per toad. Between 22% and 100% of Xenopus muelleri and X. laevis from different localities are infected with C. namaquensis.I wish to express by thanks to the Fisheries Officers and fishermen of Kajansi Fish Farm who have willingly caught Xenopus for me whenever required, and also to the many other people who have assisted me in getting specimens with which to work.I am also indebted to Mr L. Rugema who prepared most of the histological preparations, to Dr J. Green, Westfield College, London, who kindly identified Thermocyclops infrequens, and to Dr G. Rees, University College of Wales, Aberystwyth, who gave me many useful comments during the course of this work.A research grant from Makerere University College contributed towards the cost of obtaining specimens.

The life cycles of species of Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidea) parasitizing fishes in the Palearctic Region are reviewed on the basis of literary data and personal experimental observations, with special attention being paid to the development within the intermediate and definitive hosts. Planktonic crustaceans, diaptomid or cyclopid copepods (Copepoda), serve as the only intermediate hosts of all Proteocephalus species considered. A metacestode, or procercoid, develops in the body cavity of these planktonic crustaceans and the definitive host, a fish, becomes infected directly after consuming them. No previous reports of the parenteral location of metacestodes within the second intermediate host as it is in the Nearctic species P. ambloplitis have been recorded. Thus, the life cycles of Proteocephalus tapeworms resemble in their general patterns those of some pseudophyllidean cestodes such as Eubothrium or Bothriocephalus, differing from the latter in the presence of a floating eggs instead of possessing an operculate egg from which a ciliated, freely swimming larva, a coracidium, is liberated. The scolex of Proteocephalus is already formed at the stage of the procercoid within the copepod intermediate host; in this feature, proteocephalideans resemble caryophyllidean rather than pseudophyllidean cestodes. The morphology of procercoids of individual species is described with respect to the possibility of their differentiation and data on the spectrum of intermediate hosts are summarized. Procercoids of most taxa have a cercomer, which does not contain embryonic hooks in contrast to most pseudophyllidean cestodes. The role of invertebrates (alder-fly larvae-Megaloptera) and small prey fishes feeding upon plankton in the transmission of Proteocephalus tapeworms still remains unclear but these hosts are likely to occur in the life cycle. Data on the establishment of procercoids in definitive hosts, morphogenesis of tapeworms within fish hosts, and the length of the prepatent period are still scarce and new observations are needed. Whereas extensive information exists on the development of P. longicollis (syns. P. exiguus and P. neglectus), almost no data are available on the ontogeny of other taxa, in particular those occurring in brackish waters (P. gobiorum, P. tetrastomus). The morphology of P. cernuae and P. osculatus procercoids from experimentally infected intermediate hosts is described for the first time.

Infection of various Arthropods was attempted with eggs and larvae of Anguillicola crassus, a nematode parasite of the swimbladder of eels. Development up to the third larval stage was obtained only in Cyclopid Copepods and in Cypria ophthalmica (Ostracoda). Development was followed in Cyclopidae at 4 different temperatures : third-stage larvae first appeared on day 6 at 28 °C, on day 9 at 21 °C, and on day 31 at 12-14 °C. No development occurred at 4-6 °C when observation was discontinued 91 days post infection.

Cyclopid copepods from samples of fauna associated with aquatic macrophytes and plancton obtained in lotic and lentic environments were obtained from the upper Paraná River floodplain (in the states of Paraná and Mato Grosso do Sul, Brazil). Macrophytes were collected in homogeneous stands and washed. Plankton samples, taken from the water column surface and bottom, were obtained using a motor pump, with a 70 microns mesh plankton net for filtration. Twelve taxa of Cyclopidae were identified. Among them, Macrocyclops albidus albidus, Paracyclops chiltoni, Ectocyclops rubescens, Homocyclops ater, Eucyclops solitarius, Mesocyclops longisetus curvatus, Mesocyclops ogunnus, and Microcyclops finitimus were new finds for this floodplain. Eight species were recorded exclusively in aquatic macrophyte samples. Among these species, M. albidus albidus and M. finitimus presented greatest abundances. Only four species were recorded in plankton samples, and Thermocyclops minutus and Thermocyclops decipiens are limited to this type of habitat. Among these four species, T. minutus is the most abundant, especially in lentic habitats.

A Key to the British Freshwater Cyclopid and Calanoid Copepods.

Contrary to the most common latitudinal pattern of taxonomic richness, certain freshwater crustacean and molluscan groups show antitropical peaks of diversity. A previous analysis of the cyclopid and canthocamptid copepods in the Americas did not support the well-known negative relationship of taxonomic diversity and latitude, either.A recent catalogue of the continental Cyclopoida by Dussart & Defaye (2006) allowed world-scale comparisons of the species richness and rate of endemism of Cyclopidae in: the northern cold, northern temperate, tropical, southern temperate, and southern cold regions. Separate analyses of the three inland-water subfamilies revealed different latitudinal trends in these groups: while the halicyclopine and eucyclopine species richness significantly increases towards the tropics, the cyclopine diversity is very similar in the northern temperate and tropical regions despite the smaller area size of the northern temperate zone. Separate analysis of the American fauna also supported a tropical diversity peak in Eucyclopinae but showed a relatively diverse cyclopine fauna in the northern temperate zone.The aforementioned distribution patterns and tropical dominance in Euryteinae, a small marine subfamily of Cyclopidae, indicate that the family Cyclopidae originated in the tropics. This paper also discusses the latitudinal distribution of the large cyclopine genera, and attempts to infer the main features of their evolution in the temperate region: (1) cyclopine copepods invaded the temperate region at an early phase of the evolution of the subfamily; (2) a major evolution of the extant temperate taxa occurred in the northern hemisphere; (3) a substantial part of the temperate cyclopine fauna occurs in groundwater, which might indicate that in addition to a longer evolutionary time in the tropics, the greater extinction rate of the surface-water forms in the temperate region is an important factor in shaping the latitudinal diversity patterns in Cyclopidae.

During the summer months of 1956 to 1959 inclusive, the stomach contents of 2963 Heming Lake whitefish from 5–15 inches in length were examined. Data on stomach contents of 194 whitefish taken in 1945 were examined and included in this analysis. Most stomachs contained food, but lesser quantities of food per stomach and many empty stomachs were found in July and August of each year. Mayfly nymphs occurred in the stomachs most often. Other, insects eaten included dipterous larvae, especially Chaoborus and chironomids. Incidental items, constituting a smaller though important part of the fish's diet, included aquatic coleopterans, hemipterans, trichopteran larvae, cladocerans, Hyalella, hydrachnids, gastropods and, seasonally, aerial insects from the surface of the lake, and small fish. Cyclopid and calanoid copepods were found in about 1% of the stomachs. This apparently low incidence of cyclopids in the diet is considered to be sufficient to establish the relatively high infection levels of Triaenophorus found in Heming Lake fish. Some differences in diet between fish of different sizes and between seasons were shown.

Book review in this article:ADVANCES IN MARINE BIOLOGY. Volume 11 (1974). Edited by Sir Frederick S. Russell and Sir Maurice Younge.FRESHWATER LIFE IN IRELAND by Cedric S. Woods.ATLAS OF THE LIVING RESOURCES OF THE SEAS, prepared by the Food and Agriculture Organization of the United Nations, Department of Fisheries, 3rd EditionA GUIDE TO FRESHWATER AQUARIUM FISHES by G. F. Hervey and J. Hems.A KEY TO THE BRITISH FRESHWATER CYCLOPID AND CALANOID COPEPODS. J. P. Harding and W. A. Smith.FISHES OF THE WORLD by G. U. Lindberg.

Cyclopid copepods collected mainly in aquatic microcosms and semiterrestrial habitats in the Jureia Ecological Reserve are studied. Hesperocyclops herbsti and Bryocyclops campaneri are described as new species and their taxonomical relationships discussed. Females of Muscocyclops operculatus (Chappuis) are redescribed and the males described for the first time. An emended diagnosis for Muscocyclops is proposed.

Our knowledge of the freshwater cyclopid copepods of the Visayas Islands remains poor as compared to other terrestrial and aquatic fauna. This study focuses on two genera,MesocyclopsandThermocyclops, which are common components of lake plankton communities. This study included specimens collected from 59 sampling sites found in major islands (Panay, Negros, Cebu, Bohol, Leyte and Samar) and a small island (Pacijan) in the Visayas region. Four species ofMesocyclopsand three species ofThermocyclopswere identified. This includes the first record ofMesocyclops woutersiin the Philippines, which was so far unknown from insular SE Asia. The endemicMesocyclops microlasius, previously reported from Luzon Island, was also found in Lake Danao (Pacijan Island). An identification key to Philippine species ofMesocyclopsandThermocyclopsis herein provided. Geographic distribution and possible causes of the low number of species observed and their implications for further faunal studies are also discussed.

We here describe a new species of cyclopid copepod, Eucyclops bathanalicola sp. nov., parasitic on a gastropod endemic to Lake Tanganyika, Bathanalia straeleni (Cerithioidea, Paludomidae). E. bathanalicola is distinguished by the possession of praecoxal claws on the maxillules, by the modified maxillae which lack any trace of an endopod on the powerful distal claw, and by the reduction of the maxillipeds to minute unarmed lobes. In the character states exhibited by the female body, antennules and swimming legs 1–5, the new species closely resembles a typical free living Eucyclops. The impact of the adoption of parasitism as a life habit is expressed primarily in the modification of the postmandibular mouthparts. As a member of the Cyclopidae, this species represents a unique foray into a parasitic lifestyle from an otherwise free-living group of copepods inhabiting Lake Tanganyika. This is the first record of a parasitic copepod on a mollusc host within this ancient lake and only the second family of freshwater gastropods reported to host copepods.