Linking micromorphism,brooding, and hermaphroditism in brachiopods: Insights from Caribbean Argyrotheca (Brachiopoda)

In extant brachiopods, parental brooding of the larvae occurs exclusively within Rhynchonelliformea. Methods of larval protection range from simple retention of the larvae within the mantle cavity, to sophisticated brood care within highly specialized brood pouches found in Argyrotheca and Joania (Terebratulida, Megathyridoidea), Gwynia (Terebratulida, Gwynioidea), and all Thecideoidea (Thecideida). Previous studies on the reproductive biology of Argyrotheca yielded contrasting results on the epithelial origin of the brood pouches in this genus. Here, representatives of different species of Argyrotheca from the Belize Barrier Reef were examined using histological section series. Brood pouches of four species, A. cf. schrammi and Argyrotheca sp. 1–3, are of the same basic structure, formed by invaginations of the anterior body wall and connected to the visceral cavity via the metanephridia. The same four species are simultaneously hermaphroditic, suggesting that fertilization is achieved, at least partly, through selfing. One species, Argyrotheca rubrocostata, differs significantly from all others as it has no brood pouch and gonochoric gonads. Thus, the presence of brood pouches and simultaneous hermaphroditism are concluded to be correlated within Megathyridoidea and proposed to be homologous traits of Joania and several but not all species of Argyrotheca, questioning the monophyletic status of both genera. In contrast to the brood pouches of Thecideoidea, lophophoral epithelium is not involved in the formation of the pouches of Argyrotheca and Joania. Therefore, megathyridoid and thecideoid brood pouches are not homologous but evolved independently within rhynchonelliform brachiopods. All brachiopods with brood pouches share a micromorphic form and a short life span, limiting the space and time available for gamete and larval development. We suggest that the brood pouches and the hermaphroditic gonads of Argyrotheca spp. and Joania compensate these limitations by minimizing the loss of gametes and larvae, and by maximizing the chances of successful fertilization. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.     

The first recent species of the unusual brachiopod Kakanuiella (Thecideidae) from New Zealand deep waters

A new thecideid brachiopod species Kakanuiella chathamensis sp. nov. is described from deep waters on the Chatham Rise, east of South Island, New Zealand. The new species bears an unusual character combination in the shell morphology of its dorsal valve, displaying a mixture of diagnostic characters of both Recent thecideid subfamilies Thecidellininae and Lacazellinae. The resultant consequences for the systematic position of the genus Kakanuiella are discussed.     

Effect of Acanthocephala infection on the reproductive potential of crustacean intermediate hosts

The effect of a naturally acquired infection by three acanthocephalan parasites Dentitruncus truttae, Echinorhynchus truttae, and Polymorphus minutus on the reproductive potential of their intermediate host, Echinogammarus tibaldii (Amphipoda) from Lake Piediluco (Centre of Italy) was assessed. During May 2007, 1135 amphipods were collected from two different samplings and examined for larval helminths. Forty-five amphipods were infected and of those, 16 were infected with D. truttae (intensity = 1-3 larvae), 15 with E. truttae (intensity = 1-2 larvae), and 14 with P. minutus (intensity = 1 larva). The sex ratio was nearly 1:1 in all examined amphipods. One female infected with D. truttae contained six eggs in the brood pouch and another female infected with E. truttae contained five eggs. However, none of the eight female amphipods harbouring P. minutus larva contained eggs in their brood pouch. Uninfected females of the same size and body length as that of the infected females contained between 20 and 32 eggs. No acanthocephalan species were found to co-occur.     

Insight into the role of cetaceans in the life cycle of the tetraphyllideans (Platyhelminthes: Cestoda)

Four types of tetraphyllidean larvae infect cetaceans worldwide: two plerocercoids differing in size, ‘small’ (SP) and ‘large’ (LP), and two merocercoids referred to as Phyllobothrium delphini and Monorygma grimaldii. The latter merocercoid larvae parasitize marine mammals exclusively and exhibit a specialised cystic structure. Adult stages are unknown for any of the larvae and thus the role of cetaceans in the life cycle of these species has been a long-standing problem. The SP and LP forms are thought to be earlier stages of P. delphini and M. grimaldii that are presumed to infect large pelagic sharks that feed on cetaceans. A molecular analysis of the D2 variable region of the large subunit ribosomal DNA gene based on several individuals of each larval type collected from three Mediterranean species of cetaceans showed consistent and unique molecular signatures for each type regardless of host species or site of infection. The degree of divergence suggested that LP, P. delphini and M. grimaldii larvae may represent separate species, whereas SP may be conspecific with M. grimaldii. In all host species, individuals of SP accumulated in the gut areas in which the lymphoid tissue was especially developed. We suggest therefore that these larvae use the lymphatic system to migrate to the abdominal peritoneum and mesenteries where they develop into forms recognizable as M. grimaldii. The plerocercoid stage of P. delphini remains unknown. In a partial phylogenetic tree of the Tetraphyllidea, all larvae formed a clade that included a representative of the genus Clistobothrium, some species of which parasitize sharks such as the great white which is known to feed on cetaceans. A bibliographic examination of tetraphyllidean infections in marine mammals indicated that these larvae are acquired mostly offshore. In summary, the evidence suggests that cetaceans play a significant role in the life cycle of these larvae. In addition, it seems clear that cetaceans act as natural intermediate hosts for P. delphini and M. grimaldii, as within these hosts they undergo development from the plerocercoid stage to the merocercoid stage. Because tetraphyllidean species use fish, cephalopods and other marine invertebrates as intermediate hosts, the inclusion of cetaceans in the life cycle would have facilitated their transmission to apex predators such as the large, lamnid sharks. The biological significance of infections of LP in cetaceans is unclear, but infections do not seem to be accidental as such larvae show high prevalence and abundance as well as a high degree of site specificity, particularly in the anal crypts and bile ducts.     

Architecture and function of the lophophore in the problematic brachiopod Heliomedusa orienta (Early Cambrian, South China)

The detailed structure of the lophophore is a key diagnostic character in the definition of higher brachiopod taxa. The problematic Heliomedusa orienta Sun and Hou, from the Lower Cambrian Chengjiang Lagerstätte of Yunnan, southwestern China, has a well-preserved lophophore, which is unlike that of any known extant or extinct brachiopods. Based on a comparative study of lophophore disposition in H. orienta and the extant discinid Pelagodiscus atlanticus, the in- and excurrent pattern and shell orientation of H. orienta are described and discussed. Reconstructions of lophophore shape and function are based on numerous specimens and comparison with P. atlanticus. The lophophore is composed of a pair of lophophoral arms that freely arch posteriorly rather than coiling anteriorly as commonly seen in fossil and recent lingulids. The lophophore is attached to the dorsal lobe of the mantle; it has neither calcareous nor chitinous supporting structures, and is disposed symmetrically on either side of the valve midline. The mouth can be inferred to be located at the base of the two brachial tubes, slightly posterior to the anterodorsal projection of the body wall. The lophophoral arms bear laterofrontal tentacles with a double row of cilia along their lateral edge, as in extant lingulid brachiopods. The main brachial axes are also ciliated, which presumably facilitated transport of mucous-bound nutrient particles to the mouth. The unique organization of the lophophore in Heliomedusa is not like any known fossil and living brachiopods. This clearly demonstrates that H. orienta is not a member of any crown group. It is here considered as a member of the brachiopod stem group, which challenges recent interpretations of a close discinid affinity.     

肿腿蜂类寄生蜂室内控害效能评价——以松脊吉丁肿腿蜂为例

为了开发利用天敌资源防治害虫,科学而客观地评价肿腿蜂对蛀干害虫的控害作用,研究了松脊吉丁肿腿蜂(Sclerodermus sp.)对松褐天牛3龄幼虫的功能反应,建立了肿腿蜂类寄生蜂室内控害效能评价体系,并证明了其可行性。该评价体系包括供试虫源标准、寄生蜂生物学与寄生行为学观察、寄生蜂对寄主的功能反应和寻找寄主效应以及寄生蜂的忠岐指数(Y)4个部分。研究结果表明:松脊吉丁肿腿蜂具有较强的控害潜力,单头雌成虫能防治3—4头松褐天牛3龄幼虫,21d内最多可致死9.07头寄主幼虫;寄主密度对单头寄生蜂寄生作用功能反应的测定结果与对寄生作用寻找效应的测定结果以及对产卵量影响的测定结果一致;综合评价该蜂对松褐天牛3龄幼虫控制效能,释放比为1∶1(即1头肿腿蜂雌蜂:1头3龄松褐天牛幼虫)时最高,其忠岐指数Y为39.63,这可能是肿腿蜂类天敌特有的抚幼习性所致,结论也与寄生蜂生物学特性及寄生行为学观察结果相同。研究结论证明该评价体系是稳定可靠的。评价体系在利用天敌昆虫生物防治害虫时为筛选最佳寄生性天敌种类提供了可行的方法和依据。     

The morphology and independent origin of ovoviviparity in Tiphobia and Lavigeria (Caenogastropoda: Cerithioidea: Paludomidae) from Lake Tanganyika

To better understand the diversification of the endemic thalassoid (i.e. marine-like) cerithioidean gastropods of Lake Tanganyika, as well as the origin and significance of brooding among lake species, we here redescribe the anatomy and ontogeny of the ovoviviparous Tiphobia horei from Lake Tanganyika and compare it to that of Lavigeria sp. A, representing another ovoviviparous lake clade that has acquired a uterine brood pouch independently. Within the phylogenetic framework provided by recent molecular analyses, the distant relation of these two taxa is corroborated by many external and internal anatomical differences. Comparison of the brood pouches demonstrates that they each bear unique features consistent with their independent modification for brooding. Despite representing functionally analogous structures, they also share several similarities in organization likely representing symplesiomorphies of the Lake Tanganyika species flock. The ontogeny is characterized by the presence of a velum and by delayed calcification producing a characteristically wrinkled embryonic cap. Comparison with other brooding cerithioideans reveals that T. horei and Lavigeria sp. A retain many more embryos than other freshwater cerithioideans of comparable size with a uterine brood pouch, possibly facilitated by the presence of longitudinal lamellae. Compartmentalization of the oviduct and delayed calcification is strongly linked to the brooding of embryos.     

The life cycle and host specificity of Psychodiella sergenti n. sp. and Ps. tobbi n. sp. (Protozoa: Apicomplexa) in sand flies Phlebotomus sergenti and Ph. tobbi (Diptera: Psychodidae)

Two new gregarines in the recently erected genus Psychodiella (formerly Ascogregarina), Psychodiella sergenti n. sp. and Psychodiella tobbi n. sp., are described based on morphology and life cycle observations conducted on larvae and adults of their natural hosts, the sand flies Phlebotomus sergenti and Phlebotomus tobbi, respectively. The phylogenetic analyses inferred from small subunit ribosomal DNA (SSU rDNA) sequences indicate the monophyly of newly described species with Psychodiella chagasi. Ps. sergenti n. sp. and Ps. tobbi n. sp. significantly differ from each other in the life cycle and in the size of life stages. The sexual development of Ps. sergenti n. sp. (syzygy, formation of gametocysts and oocysts) takes place exclusively in blood-fed Ph. sergenti females, while the sexual development of Ps. tobbi n. sp. takes place also in males and unfed females of Ph. tobbi. The susceptibility of Phlebotomus perniciosus, Phlebotomus papatasi, Ph. sergenti, Ph. tobbi, and Phlebotomus arabicus to both gregarines was examined by exposing 1st instar larvae to parasite oocysts. High host specificity was observed, as both gregarines were able to fully develop and complete regularly the life cycle only in their natural hosts. Both gregarines are considered as serious pathogens in laboratory-reared colonies of Old World sand flies.     

Hydrozoan and protozoan epibionts on two decapod species, Liocarcinus depurator (Linnaeus, 1758) and Pilumnus hirtellus (Linnaeus, 1761), from Scotland

Crabs of the species Liocarcinus depurator and Pilumnus hirtellus, collected on the west coast of Scotland, showed hydrozoan and protozoan epibionts. The epibionts of Liocarcinus depurator were the protozoan Ephelota plana and the hydrozoans Clytia gracilis and Leuckartiara sp. The epibionts of Pilumnus hirtellus were the protozoans E. plana and Zoothamnium sp. For Liocarcinus depurator the number of Ephelota per crab fluctuated between 0 and 47 and the greatest number of suctorians were located on the chelipeds, carapace and anterior pereiopods. The hydrozoans, for Liocarcinus depurator, showed densities of 0-20 (Clytia gracilis on the second pereiopod) and 0-507 individuals per crab (Leuckartiara sp., principally on chelipeds, carapace and the fourth right pereiopod). For Pilumnus hirtellus, Ephelota plana showed densities between 3 and 56 individuals per crab, the greatest number of suctorians being located on the same areas as on Liocarcinus depurator. There was a density of 10-69 individuals per crab of Zoothamnium sp. on Pilumnus hirtellus (located on the carapace). Ephelota plana has not been observed previously as an epibiont on crustacea, nor had Zoothamnium sp. as an epibiont on Pilumnus hirtellus. Both hydrozoans, Leukartiara and Clytia, have not been previously described as epibionts on Liocarcinus depurator. Data about the morphological characteristics and distribution of these epibionts are included.     

First record of the insect pathogenic alga Helicosporidium sp. (Chlorophyta: Trebouxiophyceae) infection in larvae and pupae of Rhizophagusgrandis Gyll. (Coleoptera, Rhizophaginae) from Turkey

The predator beetle Rhizophagus grandis Gyll. (Coleoptera, Rhizophaginae) is one of the most important biological control agents, mass-bred and used to suppress populations of an important pest: the great spruce bark beetle, Dendroctonus micans. The achlorophyllous alga Helicosporidium sp. was first discovered in the pest. Later it was also found in the predator, but only in the adults. In this study, the pathogenic alga Helicosporidium sp. was discovered in larvae and early pupae of R. grandis for the first time. The morphological characteristics of the pathogenic alga were revealed by light and electron microscopy. Infection rates of Helicosporidium sp. in the larvae and pupae of R. grandis were 23.5% and 6.25%, respectively.     

Heterodera achilleae n. sp. (Nematoda: Heteroderidae) from Yarrow in Yugoslavia

Heterodera achilleae n. sp., a member of the H. rostochiensis group, is described and illustrated from roots of yarrow, Achillea millefolium L. in Sarajevo, Yugoslavia. This new, round-cyst species differs from closely related species especially as follows: (1) from H. leptonepia, by having stouter larvae (a = 21), with longer styler (25 μ), and with outlet of dorsal esophageal gland averaging 5.7 μ from base o f styler; (2) from H. millefolii, in having excretory pore at base of neck and small, straight vulval slit of 5 μ; (3) from H. rostochiensis, in having a B/A ratio (Granek''s ratio) of 1.6 ; (4) from H. tabacum, by longer female stylet, two annules on female head, and males with outlet of dorsal esophageal gland further back (5.7 μ). In addition, H. achilleae n. sp. differs from the latter three species in having prominent longitudinal striae on the anterior half, or more, of cysts and females.     

Himantura tutul sp. nov. (Myliobatoidei: Dasyatidae), a new ocellated whipray from the tropical Indo-West Pacific,described from its cytochrome-oxidase I gene sequence

It has been previously established that the Leopard Whipray, Himantura leoparda, consists of two genetically isolated, cryptic species, provisionally designated as ‘Cluster 1’ and ‘Cluster 4’ (Arlyza et al., Mol. Phylogenet. Evol. 65 (2013) [1]). Here, we show that the two cryptic species differ by the spotting patterns on the dorsal surface of adults: Cluster-4 individuals tend to have larger-ocellated spots, which also more often have a continuous contour than Cluster-1 individuals. We show that H. leoparda's holotype has the typical larger-ocellated spot pattern, designating Cluster 4 as the actual H. leoparda. The other species (Cluster 1) is described as Himantura tutul sp. nov. on the basis of the nucleotide sequence of a 655-base pair fragment of its cytochrome-oxidase I gene (GenBank accession No. JX263335). Nucleotide synapomorphies at this locus clearly distinguish H. tutul sp. nov. from all three other valid species in the H. uarnak species complex, namely H. leoparda, H. uarnak, and H. undulata. H. tutul sp. nov. has a wide distribution in the Indo-West Pacific, from the shores of eastern Africa to the Indo-Malay archipelago. H. leoparda under its new definition has a similarly wide Indo-West Pacific distribution.     

Two new species of canaliculate rudists (Dictyoptychidae) from southeastern turkey

Two new species of canaliculate rudist genus Dictyoptychus Douvillé: Dictyoptychus quadrizonalis n. sp. and Dictyoptychus vanensis n. sp., are described from the Maastrichtian limestone block of the ophiolitic unit of the Geva?-Van area, southeastern Turkey. The new species are mainly characterized by the complex structure of the canal layer of the lower valve, and also they seem to be most primitive species of Dictyoptychus and transitional between Dictyoptychus Douvillé and its presumed ancestor, Eodictyoptychus Skelton and El-Asa'ad. Many specimens of the Dictyoptychus paronai (Kühn), allows us to first determination of the upper valve shape and to study also of the lower valve canal layer.     

Microdajus tchesunovi sp. n. (Tantulocarida, Microdajidae) - A new crustacean parasite of from the White Sea

A new species of Tantulocarida, Microdajus tchesunovi sp. n., was found on tanaid host, Typhlotanais sp. of the family Nototanaidae, collected from silty sediment in the Kandalaksha Bay in the White Sea. Several tantulus larvae, developing males at different stages of metamorphosis, and early stages of parthenogenetic females were found attached to different sites of their hosts. Ultrastructure of the new species was studied with SEM. Microdajus tchesunovi sp. n. can be easily distinguished from other species of the genus Microdajus Greve by the presence of a pair of longitudinal dorsal lamellae at the anterior end of the cephalon. It is also characterized by the presence of an endopod seta on the sixth thoracopod and the absence of thoracopodal endites. A morphological comparison of species of the family Microdajidae is presented in tabular form.     

New record of nucleopolyhedroviruses in tea looper caterpillars in India

Tea production in North-East India hit a record loss due to the widespread severe outbreak of a mixed brood of three species of looper caterpillar pests of geometrid moths (Lepidoptera) in 2008-2010. In addition to Buzura suppressaria, two newly recorded geometrids, viz., Hyposidra infixaria and Hyposidra talaca have caused widespread severe damage in recent years. In the present study we report the nucleopolyhedroviruses (NPV) isolated from the tea looper caterpillar from North-East India. We identified and characterized the NPV by cloning and sequencing a partial segment of polyhedrin gene of virus infected larvae of B. suppressaria, H. talaca and H. infixaria. A comparison of deduced amino acids of polyhedrin gene among H. talaca, H. infixaria and B. suppressaria showed that same strain was found to infect all the three loopers in India, which show high sequence identity with B. suppressaria Chinese isolates. Based on the polyhedrin sequence homology, it is predicted that a variant of B. suppressaria Chinese isolate of NPV found to infect H. talaca, H. infixaria and B. suppressaria in India.     

Identification of nucleopolyhedrovirus that infect Nymphalid butterflies Agraulis vanillae and Dione juno

Dione juno and Agraulis vanillae are very common butterflies in natural gardens in South America, and also bred worldwide. In addition, larvae of these butterflies are considered as pests in crops of Passiflora spp. For these reasons, it is important to identify and describe pathogens of these species, both for preservation purposes and for use in pest control. Baculoviridae is a family of insect viruses that predominantly infect species of Lepidoptera and are used as bioinsecticides. Larvae of D. juno and A. vanillae exhibiting symptoms of baculovirus infection were examined for the presence of baculoviruses by PCR and transmission electron microscopy. Degenerate primers were designed and used to amplify partial sequences from the baculovirus p74, cathepsin, and chitinase genes, along with previously designed primers for amplification of lef-8, lef-9, and polh. Sequence data from these six loci, along with ultrastructural observations on occlusion bodies isolated from the larvae, confirmed that the larvae were infected with nucleopolyhedroviruses from genus Alphabaculovirus. The NPVs from the two different larval hosts appear to be variants of the same, previously undescribed baculovirus species. Phylogenetic analysis of the sequence data placed these NPVs in Alphabaculovirus group I/clade 1b.     

A new microsporidian species, Vairimorpha ocinarae n. sp., isolated from Ocinara lida Moore (Lepidoptera: Bombycidae) in Taiwan

A new microsporidium was isolated from Ocinara lida Moore (Lepidoptera: Bombycidae), a pest of Ficus microcarpa L. f. in Taiwan. The microsporidium produces systemic infections in O. lida larvae; the midgut epithelium, Malpighian tubules, and midgut muscle tissues were the target tissues for this isolate, and atrophied fat body tissues were found in heavily infected larvae. Two types of spores were observed, diplokaroytic spores with 11-13 coils of polar tube, and monokaryotic spores with 12 coils of the polar tube that developed within a sporophorous vesicle to form octospores. Electron-dense granules were abundant in the episporontal space of the sporophorous vesicles, and were similar to those of Vairimorpha invictae isolated from Solenopsis invicta, but different from granules or inclusions of other Vairimorpha species. Based on the phylogenetic analysis of the small subunit ribosomal DNA sequence, this isolate is unique within the Vairimorpha complex. Morphological and genetic characters showed this isolate to be a new species. It is placed in the genus Vairimorpha and is described as Vairimorpha ocinarae n. sp.     

The role of epibotic bacteria from the surface of the soft coral Dendronephthya sp. in the inhibition of larval settlement

It has been suggested that bacteria associated with soft-bodied organisms are suggested to produce bioactive compounds against the attachment of invertebrate larvae and bacteria onto the surface of these organisms. Our recent study has demonstrated that epibiotic bacteria from the surface of the soft coral Dendronephthya sp. (Coelenterata: Octocoralia, Alcyonacea) inhibit the growth of bacteria commonly found in marine natural biofilms. In the present study, the effect of 11 epibiotic bacteria isolated from the surface of Dendronephthya sp. on larval settlement of the tubeworms Hydroides elegans was examined using laboratory bioassay. Among 11 bacterial isolates, 2 strains (18%) inhibited the larval settlement of H. elegans (Haswell), 4 strains (36%) were “inductive” to larvae and the remaining 5 strains (46%) were “non-inductive”. There was no correlation between the antifouling activities of bacterial isolates and their phylogenetic origin, i.e. closely related bacterial strains showed different effects on larval settlement of H. elegans. When all “inductive”, “non-inductive” and “inhibitive” bacterial isolates were mixed in a 1:1:1 ratio, the effect of the resultant multispecies film on larval settlement became “inhibitive”. Waterborne compounds of Vibrio sp. and an unidentified α-Proteobacterium, which suppressed the settlement of H. elegans and Bugula neritina (L.) larvae, were further investigated using size fractionation and bioassay-guided enzymatic analysis. It was found that antilarval settlement compounds from these bacteria were heat-stable polysaccharides with a molecular weight >100 kDa. The results indicate that the bacteria associated with the soft coral Dendronephthya sp. may contribute to the antifouling mechanisms of the soft-bodied organisms by producing compounds that are against bacterial growth and settlement of macrofoulers on the surface of their host.