Female Genital Segments Research Articles

The interplay between Microsetella norvegica (Harpacticoida, Ectinosomatidae) and Pleurobrachia bachei (Ctenophora: Pleurobrachiidae) reveals novel trophic interactions

Despite the wide geographic distribution of Microsetella norvegica little is known regarding its interspecies interactions. In this work, we provide the first description of the interaction between the harpacticoid copepod M. norvegica and the ctenophore Pleurobrachia bachei in the southeastern Gulf of California. M. norvegica exhibited two remarkable trophic strategies during the period of this study. A parasitic strategy is proposed since M. norvegica undergoes ontogenetic changes from egg to late-copepodite in the mesoglea of the ctenophore. In contrast, adult females exhibited a short-time interaction with the ctenophore, consistent with a micropredation trophic strategy. Females occurred inside the ctenophore in three stages of maturity: lacking egg-sac (presumably fertilized), ovigerous, and with egg-sacs just detached from the female genital segment. This suggests that females enter into the ctenophore’s mesoglea to release egg-sacs, and then leave the host to continue a free life where mating occurs. Accordingly, we propose that M. norvegica is able to exhibit a protelean life history in which larvae are parasitic, but adults are free living. Copepods invaded all stages of ctenophores (i.e. from larval to adult stage ≤ 15.1 mm in sagittal diameter) with low prevalence, ranging from 0.01 to 0.4% and intensity between 1 to 3 adult females. In contrast, developmental stages from egg to copepodites reached up to 18 individuals per host. Density of M. norvegica was relatively high attaining up to 29.2 ind. 100 m−3. Positive correlation between abundance of ctenophores and copepods (r2=0.6, p < 0.05) suggests a synchronization of the interaction. Abundances were highest during the coldest season at shallow sampling stations with oligotrophic water characterized by low levels of chlorophyll-a, and moderate oxygenated waters.

First record of the Marine Calanoid Copepod Pseudodiaptomus c.f. ardjuna from Shatt Al-Arab River, Iraq

The marine calanoid copepod Pseudodiaptomus c.f. ardjuna (Brehm, 1953) was recorded from some freshwater habitats in some regions of the Shatt A-Arab River during March – July 2009. These regions include Al-Kurnish area, Al-Sindebad Island during April-August 2009 and at Al-Gurna city on March 2009 only. The species is briefly described in this work and its morphological characters are compared with earlier descriptions from Iraqi coastal water, like the total length of female and male, body shape, female genital segment, the shape of the male posterior prosomal segment and number of the setae of the furcal rami.

Homology of the genital sclerites ofMegaloptera (Insecta:Neuropterida) and their phylogenetic relevance

AbstractThe genitalia ofMegaloptera are crucial for taxonomic identification and represent a significant component of characters for phylogenetic interpretation of this order. However, several complex genital structures, especially those related to segments 9 and 11 inMegaloptera, have yet to be subjected to a comprehensive survey of homology. The terminology for genital sclerites has been variously and even incorrectly used by different authors, a fact which could lead to much confusion about character evolution. In this paper, we first present a comprehensive morphological comparison of the sclerites of male and female genital segments in 23 megalopteran genera representing all major lineages ofCorydalinae,Chauliodinae andSialidae. Accordingly, we then provide new interpretations on the homology of the genital sclerites which often appear to be considerably different amongMegaloptera. Based on our new and revised homology assessments, we conclude that: (i) the small to medium‐sized sclerite beneath the ectoprocts in males ofSialidae represents the fused gonocoxites 11; (ii) the male gonocoxites 11 inCorydalidae are largely reduced and are sometimes retained as a small sclerite beneath the anus; (iii) the predominant sternite‐like sclerite of the female abdominal segment 8 represents the fused gonocoxites 8; and (iv) a pair of sclerites amalgamated with the lateral arms of male gonocoxites 10 inChauliodinae is the gonocoxites 9. Furthermore, based on our genital homology assessments, we reconstruct an intergeneric phylogeny including all genera ofMegaloptera using genital characters in a parsimonious analysis to test their phylogenetic relevance. The phylogeny herein recovered is largely congruent with the results from several previous studies, thus underlying the significant phylogenetic relevance of the megalopteran genital sclerites. The present work provides new insights into the evolution of insect genitalia.

A revision of Megagraphydrus Hansen (Coleoptera, Hydrophilidae): synonymization with Agraphydrus Régimbart and description of seven new species.

The genus Megagraphydrus Hansen, 1999 is revised. Eleven of the twelve previously described species are recognized as valid, with Megagraphydrus wangi Hebauer, 2000 syn. nov. found to be a junior synonym of M. politus Hansen, 1999. Most significantly, Megagraphydrus itself is found to be a junior synonym of Agraphydrus Régimbart, 1903. The species are assigned to the subgenus Agraphydrus. This nomenclatural act results in the following new combinations: Agraphydrus (Agraphydrus) anhuianus (Hebauer, 2000) comb. nov., A. (A.) attenuatus (Hansen, 1999) comb. nov., A. (A.) jaechi (Hansen, 1999) comb. nov., A. (A.) luteilateralis (Minoshima & Fujiwara, 2009) comb. nov., A. (A.) malayanus (Hebauer, 2000) comb. nov., A. (A.) politus (Hansen, 1999) comb. nov., A. (A.) puzhelongi (Jia, 2010) comb. nov., A. (A.) regularis (Hansen, 1999) comb. nov., A. (A.) siamensis (Hansen, 1999) comb. nov., A. (A.) superans (Hebauer, 2000) comb. nov., and A. (A.) uvaensis (Hebauer, 2000) comb. nov. All species are redescribed with the exclusion of A. superans, A. luteilateralis, and A. puzhelongi. Seven new species are described: Agraphydrus (Agraphydrus) biprojectus sp. nov., A. (A.) coronarius sp. nov., A. (A.) decipiens sp. nov., A. (A.) insidiator sp. nov., A. (A.) masatakai sp. nov., A. (A.) montanus sp. nov., A. (A.) thaiensis sp. nov. Digital and SEM photographs are provided, and the male and female genital segments are illustrated and described.

A revision of Megagraphydrus Hansen (Coleoptera, Hydrophilidae): synonymization with Agraphydrus Régimbart and description of seven new species

The genus Megagraphydrus Hansen, 1999 is revised. Eleven of the twelve previously described species are recognized as valid, with Megagraphydrus wangi Hebauer, 2000 syn. nov. found to be a junior synonym of M. politus Hansen, 1999. Most significantly, Megagraphydrus itself is found to be a junior synonym of Agraphydrus Régimbart, 1903. The species are assigned to the subgenus Agraphydrus. This nomenclatural act results in the following new combinations: Agraphydrus (Agraphydrus) anhuianus (Hebauer, 2000) comb. nov., A. (A.) attenuatus (Hansen, 1999) comb. nov., A. (A.) jaechi (Hansen, 1999) comb. nov., A. (A.) luteilateralis (Minoshima &amp; Fujiwara, 2009) comb. nov., A. (A.) malayanus (Hebauer, 2000) comb. nov., A. (A.) politus (Hansen, 1999) comb. nov., A. (A.) puzhelongi (Jia, 2010) comb. nov., A. (A.) regularis (Hansen, 1999) comb. nov., A. (A.) siamensis (Hansen, 1999) comb. nov., A. (A.) superans (Hebauer, 2000) comb. nov., and A. (A.) uvaensis (Hebauer, 2000) comb. nov. All species are redescribed with the exclusion of A. superans, A. luteilateralis, and A. puzhelongi. Seven new species are described: Agraphydrus (Agraphydrus) biprojectus sp. nov., A. (A.) coronarius sp. nov., A. (A.) decipiens sp. nov., A. (A.) insidiator sp. nov., A. (A.) masatakai sp. nov., A. (A.) montanus sp. nov., A. (A.) thaiensis sp. nov. Digital and SEM photographs are provided, and the male and female genital segments are illustrated and described.

On the Origin of Grasshopper Oviposition Behavior: Structural Homology in Pregenital and Genital Motor Systems

In female grasshoppers, oviposition is a highly specialized behavior involving a rhythm-generating neural circuit, the oviposition central pattern generator, unusual abdominal appendages, and dedicated muscles. This study of Schistocerca americana (Drury) grasshoppers was undertaken to determine whether the simpler pregenital abdominal segments, which do not contain ovipositor appendages, share common features with the genital segment, suggesting a roadmap for the genesis of oviposition behavior. Our study revealed that although 5 of the standard pregenital body wall muscles were missing in the female genital segment, homologous lateral nerves were, indeed, present and served 4 ovipositor muscles. Retrograde labeling of the corresponding pregenital nerve branches in male and female grasshoppers revealed motor neurons, dorsal unpaired median neurons, and common inhibitor neurons which appear to be structural homologues of those filled from ovipositor muscles. Some pregenital motor neurons displayed pronounced contralateral neurites; in contrast, some ovipositor motor neurons were exclusively ipsilateral. Strong evidence of structural homology was also obtained for pregenital and ovipositor skeletal muscles supplied by the identified neurons and of the pregenital and ovipositor skeletons. For example, transient embryonic segmental appendages were maintained in the female genital segments, giving rise to ovipositor valves, but were lost in pregenital abdominal segments. Significant proportional differences in sternal apodemes and plates were observed, which partially obscure the similarities between the pregenital and genital skeletons. Other changes in reorganization included genital muscles that displayed adult hypertrophy, 1 genital muscle that appeared to represent 2 fused pregenital muscles, and the insertion points of 2 ovipositor muscles that appeared to have been relocated. Together, the comparisons support the idea that the oviposition behavior of genital segments is built upon a homologous, segmentally iterated motor infrastructure located in the pregenital abdomen of male and female grasshoppers.

Taxonomy of the genus Metolinus Cameron (Coleoptera, Staphylinidae, Staphylininae, Xantholinini) from China with description of three new species

This paper studies the taxonomy of the genus Metolinus Cameron, 1920 (Coleoptera: Staphylinidae, Staphylininae, Xantholinini) from China and describes three new species: Metolinus xizangensis sp. n. from Xizang (Tibet), Metolinus emarginatus sp. n. fromSichuan, and Metolinus binarius sp. n. from Yunnan. The Chinese fauna of the genus is thus increased to 8 species in total. A key to eight Chinese species is provided. Female genital segments and other important morphological characters are illustrated in line drawings for the new species as well as Metolinus shanicus Bordoni, 2002 and Metolinus gardneri (Cameron, 1945). The text also provides color plates with habitus photographs and a map to show the species’ geographical distribution pattern. The type specimens of the new species are deposited in Institute of Zoology, the Chinese Academy of Sciences (IZ-CAS).

Description of Two New Species of Ridgewayia (Copepoda: Calanoida) from Anchialine Caves in the Galapagos Archipelago

Two new calanoid copepods, Ridgewayia delfine sp. nov. and Ridgewayia tunela sp. nov., are described from anchialine caves in the Galapagos Archipelago. Details of the female genital segment and the female and male fifth legs help distinguish these species from each other and from other members of the same genus. The two new species belong to the Ridgewayia marki species-group, which are found predominantly in the Caribbean with one member in the Mediterranean and one in the Indo-West Pacific. These are the first species of Ridgewayia described from the Eastern Pacific. The volcanic origin of the Galapagos necessitates the dispersal of these ridgewayiids to the islands from other regions. It is currently thought that Ridgewayia is a relict from the Tethyan Sea and that members of the marki-species group crossed from the Caribbean into the Pacific during the circumtropical existence of this sea. The possibility remains that this crossover and colonization of the Galapagos occurred more recently while the Panama seaway remained open. It is clear that the current knowledge of the ridgewayiids is insufficient for a definitive conclusion. Further exploration is necessary to generate an exhaustive list of species of Ridgewayidae and their distribution.

EIGHT NEW SPECIES OF HYGIA (PTEROCOLPURA) BLÖTE (HETEROPTERA: COREIDAE: COLPURINI) FROM MALAYSIA (BORNEO)

Abstract Eight new species of Hygia from Malaysia (Borneo) are described, and included in the tribe Colpurini. The new species are as follows: H. alta from Sarawak, H. borneensis from Sarawak, H. mjobergi from Sarawak and Sabah, H. murudina from Sarawak and Sabah, H. reyesi from Sarawak and Sabah, H. tomokunii from Sarawak and Sabah, H. vantoli from Sabah, and H. webbi from Sarawak. Dorsal view illustrations and drawings of the male genital capsule, and female genital segments are provided.

The egg string attachment mechanism of selected pennellid copepods

The anatomy of the hook apparatus that attaches egg strings to the fish parasites Haemobaphes cyclopterina, Lernaeocera branchialis, Lernaeocera lusci, Lernaeenicus sprattae, Sarcotretes scopeli and Pennella balaenoptera (Copepoda: Pennellida) is described and illustrated. The hook rises from a cupulate base, extending posteriorly and anteriorly in the body cavity. The suspension of the apparatus in the trunk of the different species differs, but the function is similar. The hook tip enters the genital antrum, nearly penetrates the proximal end of the egg string, and continues into a notch on the antrum wall. The apex of the egg string acquires a concave depression like the finger end of a glove. In this way the string is mechanically attached inside the female genital segment. The mobile ectoparasites Lepeophtheirus salmonis and Hatschekia hippoglossi have hooks which function similarly, but perforate the strings.

Senecella siberica n. sp. and the position of the genus Senecella in Calanoida classification

Senecella calanoides Juday has been reported from fresh-water lakes of North America, Northern Siberia and inshore brackish waters of Kara and Laptev Seas. Investigation of 11 females and 2 males from the brackish waters of Neelov Bay (Laptev Sea) shows that second species, Senecella siberica sp. n., can be distinguished from S. Calanoides Juday by the greater size, a slightly asymmetrical female genital segment, the 3 external spines on the 3d exopod of 2 to 4th swimming legs and by more longer left endopod digitiform process of the male 5th legs. S. siberica seems to be brackish-water euryhaline species, inhabiting brackish waters with salinity from 1 to 22‰. The genus belongs to the family Aetideidae and is the only genus with freshwater representatives.

The Sperm Transfer System in Kinbergonuphis simoni (Polychaeta:Onuphidae).

Tube dwelling Kinbergonuphis simoni (Santos, Day and Rice) achieves a 98.9% fertilization efficiency by means of a sperm transfer system involving spermatophores and seminal receptacles. The spermatophores are mushroom-shaped structures released as clumps. The seminal receptacles are paired sac-like organs embedded in the dorsal epidermis of female genital segments. Males release spermatophores into the environment, and females pick them up with their ventral palps and first pair of parapodia. Stored sperm remain viable for fertilization for at least one month. Spermatophore release and egg laying are independent of the presence of the opposite sex. Advantages associated with this system are discussed, and include asynchronous reproduction, a long breeding season, reduced sperm loss, and reduced exposure to risks. This sperm transfer mode is the first reported in the family Onuphidae and is proposed for other small, tube-dwelling onuphids.

Taxonomic value of minute structures on the genital segment ofPontellina females (Copepoda: Calanoida)

Scanning electron micrographs of the female genital segment ofPontellina spp. reveal fine-scale structures of systematic and phylogenetic interest. The structures are integumental organs and patches of spinules usually overlooked during routine examinations with a light microscope. Number and arrangement of these structures provide a set of character states and delineate a morphocline in accord with phylogenetic relationships hypothesized previously on the basis of other characters. A basic feature of patchiness shown by the spinules is of ontogenetic interest: arrangement of these patches appears to demarcate individual epidermal cells. The adaptive value of spinules and integumental organs is considered in the light of communicative requirements between partners engaged in courtship and copulation. The specimens used were collected on various expeditions in the warm-water belt of the world oceans and mostly studied during 1977.

Collocheres (Copepoda: Siphonostomatoida) Associated with the Crinoid Capillaster multiradiatus in the Indo-Pacific

Two siphonostomatoid copepods are associated with the crinoid Capillaster multiradiatus in Madagascar and in the Moluccas. Collocheres prionotus n. sp. may be differentiated from its congeners by the three pairs of small spines on the lateral margins of the female genital segment and by the absence of a palp on the mandible. Collocheres uncinatus is reported for the first time from this crinoid. Eleven members of the genus Collocheres Canu, 1983 are currently known to be associated with crinoids or ophiuroids. In the Indo-Pacific, copepods belonging to this genus are abundant on at least 10 species of shallow-water crinoids in the Gulf of Aqaba, Madagascar, northern Australia and the Great Barrier Reef, Philippines, Japan, Moluccas, and New Caledonia (Ho, 1982; Humes, 1987; Stock 1966). The purpose of this paper is to describe a new species of Collocheres and to record a new host for Collocheres uncinatus Stock, 1966, both found on Capillaster multiradiatus (Linnaeus) in Madagascar and the Moluccas. MATERIALS AND METHODS The crinoids were isolated immediately after collection in sea water in plastic bags. Later, they were washed in the same sea water to which a small amount of 95% ethanol had been added to make approximately a 5% solution. After passing the water through a fine net (120 holes per 2.5 cm), the copepods were picked from the sediment retained. The copepods were studied using the wooden slide/lactic acid technique described by Humes & Gooding (1964). All figures were drawn with the aid of a camera lucida. The letter after the explanation of each figure refers to the scale at which it was drawn. The abbreviations used are: A1, first antenna; A2, second antenna; and OC, oral cone. The collection of specimens in Madagascar was made possible by the United States Program in Biology of the International Indian Ocean Expedition. Copepods in the Moluccas were collected by the author during the Alpha Helix East Asian Bioluminescence Expedition, which was supported by the National Science Foundation of the United States under grants OFS 74 01830 and OFS 74 02888 to the Scripps Institution of Oceanography and grant BMS 74 23242 to the University of California, Santa Barbara. The study of the material was supported by a National Science Foundation grant, BSR 8514561. I thank Miss Ailsa M. Clark, British Museum (Natural History), for the identifications of the crinoids from Madagascar and Dr. Donald McCurda, Jr., University of Michigan, for identifying the crinoids from the Moluccas. TRANS. AM. MICROSC. SOC., 109(1): 61-68. 1990. ? Copyright, 1990, by the American Microscopical Society, Inc. This content downloaded from 207.46.13.123 on Tue, 28 Jun 2016 07:18:39 UTC All use subject to http://about.jstor.org/terms TRANS. AM. MICROSC. SOC.

Stimulation in vivo de l'androgène testiculaire par Phormone cérébrale chez l'Annelide Oligochète,Eisenia foetidaf.typica Sav./ STIMULATION OF TESTICULAR ANDROGEN IN VIVO BY CEREBRAL HORMONE IN THE OLIGOCHAETE ANNELID,EISENIA FOETIDAVAR.TYPICASAV.

In sexually active Eisenia foetida, the simultaneous implantation of ganglia of the central nervous system, ovaries and testes showed that the cerebral hormone stimulated the production of testicular androgen and maintained spermatogenesis. These results confirm those previously obtained by in vitro culture. When cerebral ganglia (CG) were implanted at different levels in the earthworm (CG segment or segment 7, testicular or ovarian segment), the percentage of testes transformed into ovotestes varied from 5 to 9%. The testicular androgen released under the control of CG was then able to masculinize partially 17–28% of the ovaries. On the other hand, some ganglia of the ventral nerve cord, such as subesophageal ganglia or ganglia of male or female genital segments, had no stimulating endocrine action on secretion of testicular androgen and on maintenance of the spermatogenetic activity of the gonia. In the presence of these different ganglia, no masculinization of ovaries occurred, and the percentage of transformation of testes into ovotestes reached 29, 42 and 41%, respectively.

Demonstration by organ culture of a cerebral hormone stimulating the secretion of testicular androgen in the oligochaete annelid,Eisenia foetidaf.typicaSav.

Previous culture experiments revealed that, in reproductively active E. foetida, the central nervous sytem (CNS) produces a neurohormone necessary for the secretion of an androgen by testes. The tracing of the origin of this neurohormone has now been done by culturing in vitro ovaries and testes with different ganglia of the nerve cord. In the presence of cerebral ganglia (CG), the percentage of testes transformed into ovotestes was low (3%), while reaching respectively 32% and 17% in the associations with sub-esophageal ganglia (SEG) or ganglia of the male or female genital segments (GS ♂ or ♀). Only the neurohormone produced by CG was able to stimulate secretion of the testicular androgen, the existence of which was proved by previous experiments. The secretion of this androgen was enough to transform 28% of the ovaries into ovotestes. On the other hand, no masculinization of the ovaries was observed in the presence of various ganglia of the ventral nerve cord (SEG, GS ♂ or ♀). It appears, therefore, th...

Copepoda (cyclopoida, Lichomolgidae) associated with the Alcyonacean Nephthea in the moluccas

In the Moluccas five lichomolgid copepods are associated with soft corals of the genus Nephthea. Paramolgus nephtheanus, n. sp., from Nephthea chabrolii, Nephthea sphaerophora, Nephthea cupressiformis, Nephthea albida, and Nephthea galbuloides, Paramolgus prominulus, n. sp., from N. sphaerophora, N. cupressiformis, and N. albida, and Paramolgus accinctus, n. sp., from N. sphaerophora, N. cupressiformis, N. albida, and N. galbuloides are distinguished from conspecifics by combinations of several characters. These include, among others, the length of the caudal ramus, the form of the female genital segment, and the shape of leg 5 in the female. Mecra ellipsaria, n. gen., n. sp., from N. sphaerophora has only two setae on the fourth segment of the first antenna, the formula II, 2 on the third endopod segment of leg 3, and five aesthetes on the second segment of the first antenna of the male. In Metaxymolgus lumarius, n. sp., from N. galbuloides and N. cupressiformis, the two claws on the second antenna are longer than the fourth second antennal segment and the proximal inner expansion of leg 5 in the female has a thorn-like process. Metaxymolgus aculeatus (Humes & Ho, 1968) occurs on N. chabrolii, N. sphaerophora, N. cupressiformis, N. albida, and N. galbuloides.

Patterns of spermatophore distribution and placement in Euchaeta norvegica (Copepoda: Calanoida)

The spermatophore in the Copepoda is an elongated flask-shaped object produced by the male copepod in which are contained the sperm and associated secretions. The male must attach the spermatophore to the female genital segment in such a position that the opening to the neck of the spermatophore, through which the sperm come out, is in contact with the opening of the female cavity. Placement of the spermatophore elsewhere, in such a manner that connexion with the female genital cavity is not achieved, may not cause fertilization and will waste sperm.