Copulatory Bursa Research Articles

Survey the Occurrence of Globocephalus urosubulatus (Nematoda: Ancylostomatidae) in Wild Boars (Sus scrofa) in the State of São Paulo, Brazil.

Although previous studies have characterized the helminth fauna of wild boars kept in captivity in Brazil, records on these helminths in free-ranging animals are still scarce. In view of this, we aimed in our work to investigate the occurrence and morphological and morphometric characteristics of gastrointestinal helminths in wild Sus scrofa from the northwest region of the State of São Paulo, Brazil. The digestive systems of 10 animals (5 males and 5 females of different ages) were used in this study. Each anatomical segment was washed and sieved under running water, and the helminths were separated and identified using light and scanning electron microscopy, according to their morphological characteristics. A total of 2750 (1152 males and 1598 females) nematode specimens were collected from the small intestine of these wild boars, and all of them presented the morphological characteristics of Globocephalus urosubulatus. However, one characteristic is of particular interest because it has not yet been reported in the literature: a marked asymmetry between the lobes and their respective rays of the copulatory bursa, with the left one being larger than the right one. In this research, we identified the presence of G. urosubulatus in all the examined free-ranging wild boars and reported for the first time in the literature the asymmetry in the copulatory bursa.

Two New Species of Freshwater Planarian (Platyhelminthes, Tricladida, Dugesiidae, Dugesia) from Southern China Exhibit Unusual Karyotypes, with a Discussion on Reproduction in Aneuploid Species

Two new species of the genus Dugesia from Southern China are described by applying an integrative approach, including morphological, karyological, histological, and molecular information. In the molecular phylogenetic tree, the two new species, Dugesia pendula Chen & Dong, sp. nov. and Dugesia musculosa Chen & Dong, sp. nov., fall into an Eastern Palearctic/Oriental clade and an Oriental/Australasian clade, respectively, while sharing only a rather distant relationship. The separate specific status of the two new species is supported also by their genetic distances. Dugesia pendula is characterized by the following features: symmetrical openings of the oviducts into the bursal canal, a duct between seminal vesicle and diaphragm, small diaphragm, dorsally located seminal vesicle, a penis papilla suspended from the dorsal wall of the male atrium, and mixoploid karyotype with diploid complements of 2n=2x=14+0−1 B-chromosome and triploid complements of 2n=3x=21+0−1 B-chromosome, with all chromosomes being metacentric. Dugesia musculosa is characterized by the following features: asymmetrical openings of the oviducts into the bursal canal; a ventrally displaced ejaculatory duct with a terminal opening; two diaphragms; a bursal canal provided with a strong, thick layer of circular muscle, which extends from the copulatory bursa to the common atrium and gonoduct; the left vas deferens opening at the midlateral wall of the seminal vesicle, while the right sperm duct opens at the dorsolateral wall of the seminal vesicle; and karyotype consisting of complicated diploid and aneuploid mosaicism, with diploid complements of 2n=2x=16 and 2n=2x=16−17th-18th, with all chromosomes being metacentric. The uncommon karyotypes, combined with the asexual reproduction of aneuploid animals, are evaluated in the context of the relationship between ploidy levels and reproductive modalities in the genus Dugesia.

New Insights on the Male and Female Reproductive Organs of Centrorhynchus globocaudatus (Acanthocephala), Intestinal Parasite of Birds of Prey.

Acanthocephalans are dioecious parasites that gain sexual maturity in the alimentary canal of their definitive hosts (gnathostome vertebrates). This initial survey by light and transmission electron microscopy was conducted on the functional organization of the ovarian balls and uterine bell in mature females and on Saefftigen's pouch and the copulatory bursa in males. We studied these structures via the example of Centrorhynchus globocaudatus (Palaeacanthocephala) in Falco tinnunculus and Buteo buteo, from the Province of Ferrara (Northern Italy). Our study confirms that the ovarian balls have surface microvilli and consist of a multinucleate supporting syncytium and a cellular region with oogonial syncytium, single germ cells, zygotes, and shelled eggs. Germ cells are embedded in the supporting syncytium. The ultrastructural features of these components and data on fertilization, shell formation, and release from the ovarian ball, alongside insights into the likely egg sorting function of the uterine bell, are provided. We also present light and electron microscopy observations of Saefftigen's pouch and a suggestion regarding its hydrostatic functioning in the eversion of the copulatory bursa.

SPSL1 is essential for spermatophore formation and sperm activation in Spodoptera frugiperda.

The reproductive process in various species has undergone evolutionary adaptations at both the physiological and molecular levels, playing a significant role in maintaining their populations. In lepidopteran insects, the spermatophore is a unique structure formed in the female reproductive system, in which sperm storage and activation take place. It is known that the formation of the spermatophore is regulated by seminal fluid proteins derived from males. However, studies investigating the genetic mechanisms behind spermatophore formation in lepidopterans have been limited. In this study, our focus was on SPSL1, a gene that encodes a trypsin-type seminal fluid protein in Spodoptera frugiperda, a pest species with global invasive tendencies. Our findings revealed that SPSL1 expression was predominantly observed in the male reproductive tracts, and the disruption of this gene resulted in male sterility. Surprisingly, fluorescence analysis indicated that the absence of SPSL1 did not affect spermatogenesis or sperm migration within the male reproductive system. However, when females mated with SPSL1-mutant males, several defects were observed. These included disruptions in spermatophore formation, sperm activation in the copulatory bursae, and sperm migration into the spermathecae. Additionally, mass spectrometry analysis highlighted reduced levels of energy-related metabolites, suggesting that SPSL1 plays an essential role in promoting hydrolysis reactions during copulation. Consequently, our study demonstrates that SPSL1 is crucial for male fertility due to its functions in spermatophore formation and sperm activation. This research provides valuable insights into the genetic factors underlying reproductive processes in lepidopteran insects and sheds light on potential strategies for controlling invasive pest populations.

TISSUE ORGANIZATION OF THE MALE REPRODUCTIVE SYSTEM OF THE ACANTHOCEPHALAN, <i>ACANTHOCEPHALUS TENUIROSTRIS</i> (PALAEACANTHOCEPHALA, ECHINORHYNCHIDA)

Histological and electron microscopic studies of the male reproductive system of the acanthocephalan, A-canthocephalus tenuirostris show that its organization and structure are generally similar to those characteristic of representatives of the class Palaeacanthocephala. In its composition, paired testes with sperm ducts, which are combined into a common vas deferens, six cement glands, Sefftigen’s pouch, a copulatory bursa and a penis are identified. The distal part of the vas deferens, Sefftigen’s pouch, the bursa and the base of the penis are surrounded by the genital sheath. The shells of the organs of the reproductive system are shown to be formed by fragments of muscle tissue immersed into fibrous intercellular material, which most likely is a derivative of muscle tissue. The most powerful muscle bundles were found in the genital sheath. It appears impossible to confirm the existing opinion concerning a symplastic organization of the organs of the reproductive system in male acanthocephalans.

Morphometric characteristics of the nematode Oesophagostomum venulosum (Nematoda, Strongylida) isolated from the domestic goat

The nematodes of the genus Oesophagostomum Molin, 1861 parasitize in the large intestine of ruminants and are widely represented in the terrestrial ecosystems of many countries of the world. One of the most common species of this genus in small ruminants is Oesophagostomum venulosum Rudolphi, 1809. The validity of this species was established using morphological and molecular genetic methods, the importance of which is still relevant. The aim of our research was to determine the morphological and metric characteristics of O. venulosum nematodes isolated from domestic goats in Ukraine. The differential parameters of mature males and females of nematodes of this species are described and illustrated, and the obtained data is analyzed in the context of the findings of other authors. The taxonomic morphological characters of O. venulosum include the presence of a pronounced cuticular vesicle at the head end, inner and external corona radiata, cervical papillae located behind the esophagus; in males, the presence of prebursal papillae in front of the tail bursa and features of its structure, thin and tubular spicules and features of the structure of their proximal and distal ends; in females, features of the structure of the tail end, vulva and its location. 35 morphometric indicators were determined and proposed to be used in the identification of O. venulosum in males, and 29 indicators in females. Of these, 20 parameters characterize the general body structure (the length and width of the nematode, the dimensions of the mouth capsule, cervical vesicle, esophagus, the length of the inner and outer radial crowns, the location of the nerve ring and cervical papillae, as well as their sizes). In male nematodes of this species, 15 indicators characterize the metric parameters of the reproductive system (the size of the spicules in their various parts, gubernaculum, genital cone, genital papillae and their location, the width of the copulatory bursa). In females, 7 indicators are described that characterize the length of the vagina, the ovipositor, the location of the vulva and anus, the width of the body in the area of the vulva and anus, as well as two metric parameters of eggs. The identified and described morphometric characters of O. venulosum males and females based on microscopic studies can be an economical and effective method for researchers to accurately identify nematodes of this species. The information obtained in this study can contribute to the timely planning of control and prevention strategies for the parasitism of these nematodes on goat farms.

Molecular phylogeny of the Pseudaliidae (Nematoda) and the origin of associations between lungworms and marine mammals.

Metastrongyloid lungworms from the family Pseudaliidae infect the lungs and cranial sinuses of cetaceans worldwide, except Stenuroides herpestis, which exhibits a striking terrestrial association with the Egyptian mongoose, Herpestes ichneumon. Previous phylogenies of the Metastrongyloidea that included some (2-7) marine species of the Pseudaliidae confirmed that these species are closely related, but also grouped species of Parafilaroides (family Filaroididae) between the members of the Pseudaliidae. In this study we extracted DNA from representatives of all six genera of the Pseudaliidae and amplified the second internal transcribed spacer (ITS2) and cytochrome c oxidase subunit I (cox1) genes in order to investigate the concept of the Pseudaliidae as a monophyletic unit. Three species of Parafilaroides were also included in the analysis. Maximum Likelihood and Bayesian Inference analyses of the concatenated genes resulted in a well-supported clade including the marine pseudaliids, S. herpestis and Parafilaroides spp. These findings validate the status of S. herpestis as a pseudaliid species and support the inclusion of Parafilaroides in the Pseudaliidae. Although males of Parafilaroides spp. lack a copulatory bursa, this trait itself is highly variable in the Pseudaliidae, which include abursate species. Furthermore, life cycles seem to be closely similar between both taxa. When all the available phylogenetic data on the Metastrongyloidea were mapped of onto a phylogeny of the Laurasiatheria, there was a strong suggestion that the Pseudaliidae may have descended from ancestors infecting terrestrial carnivores, with odontocetes being colonized in the marine realm as a result of a host-switching event from pinnipeds through shared fish prey. The origin of the association between S. herpestis and mongooses remains uncertain.

Ferron L. Andersen (1931-2022).

Nematodes of the family Molineidae are the most frequent helminths reported infecting the digestive tract of South American amphibians. The molineid genus Kentropyxia Baker, 1982 includes only 2 nominal species of parasitic nematodes: Kentropyxia sauria Baker, 1982 and Kentropyxia hylae Feitosa et al., 2015 both from the eastern Amazon. We describe a new nematode species of Kentropyxia parasitizing Boana boans, Boana geographica, and Boana wavrini from 2 different locations in the eastern Amazon. Kentropyxia bakeri n. sp. has corona radiata composed of unequal lappets, a smooth cephalic vesicle, a claviform esophagus, and well-developed cuticular longitudinal ridges composing the synlophe. Females have a well-developed ovojector, with amphidelphic uteri, and a simple tail. Males have a type I copulatory bursa and complex robust spicules divided into an outer process and fan-like branches (1 dorsolateral and 1 ventrolateral) divided into numerous projections. We observed intraspecific variation among specimens from different hosts, which can be related to factors regarding the hosts, the parasite, their location, and/or their ecology. The new species differs from its congeners by the presence of cervical alae composed of a series of modified oblique ridges which are absent in K. sauria but are composed of single expanded cuticle projections in K. hylae. This species is the third described for the genus and the second reported for a hylid host in the Neotropics.

Phylogenetic analyses based on molecular and morphological data reveal a new species of Strigea Abildgaard, 1790 (Digenea: Strigeidae) and taxonomic changes in strigeids infecting Neotropical birds of prey.

Members of the genus Strigea Abildgaard, 1790 are endoparasites of birds distributed worldwide. Adults of an undescribed species of the genus Strigea were collected from the intestines of two hawk species (Rupornis magnirostris and Accipiter coperii). Other species identified as Parastrigea macrobursa that were described in Argentina were also recovered from two hawk species (Buteogallus urubitinga and Buteogallus anthracinus) in three localities along the coasts of Mexico. Specimens of the two species were sequenced for three molecular markers, the internal transcribed spacers locus (ITS1-5.8S rDNA- ITS2) and the domains D1-D3 from the large subunit from nuclear ribosomal DNA and the cytochrome c oxidase subunit 1 from mitochondrial DNA. The newly sequenced specimens were aligned with other strigeids sequences downloaded from GenBank. Maximum likelihood and Bayesian analyses inferred with each molecular marker revealed that our specimens of Strigea sp. formed an independent lineage, which is recognized herein as a new species, Strigea magnirostris n. sp., representing the first species in Mexico and the 16th in the Neotropical region. Morphologically, the new species is distinguished from other congeneric species from the Americas by having an oral sucker with several papillae around it, well-developed pseudosuckers (118-248 μm), a tegument covered with tiny spines, a larger cone genital (193-361 × 296-637) and a larger copulatory bursa (247-531 × 468-784). Our phylogenetic analyses revealed that P. macrobursa is not closely related to other members of the genus Parastrigea and is nested within Strigea, suggesting that P. macrobursa should be transferred to Strigea to form Strigea macrobursa n. comb., expanding its distribution range from Mexico to Argentina. Finally, the analyses also revealed that the taxonomy and systematics of Strigea should be re-evaluated, combining morphological and molecular characteristics.

NEW SPECIES OF ALIPPISTRONGYLUS (TRICHOSTRONGYLINA: NIPPOSTRONGYLINAE) FROM THE ELEGANT RICE RAT, EURYORYZOMYS NITIDUS, OF LA CONVENCIÓN, PERU.

A new species of AlippistrongylusDigiani and Kinsella, 2014, was found in the intestines of the elegant rice rat, Euryoryzomys nitidus, collected in the Amazon rainforest. These mammals were preserved in alcohol and archived in the Colección Científica de Mamíferos del Museo de Historia Natural de la Universidad Mayor de San Marcos and accessed for the observation and investigation for the diversity of their endo-parasites. A total of 857 worms were recovered from the 3 individuals examined. Morphological investigations and comparisons with the only known species of the genus indicate that this is an undescribed species. These nematodes feature the diagnostic characteristic of the genus, being a bifurcated posterior end that consists of a tail and a conical appendage near the level of the vulva and uninterrupted ridges in the synlophe of unequal size. However, the orientation of this conical appendage on the female tail, features of the synlophe, and shape of the copulatory bursa warrant the proposal of an amended diagnosis to include character variability detected in the new species.

SCANNING ELECTRON MICROSCOPIC (SEM) STUDY OF NEMATODE PARASITES OF GOAT IN LUCKNOW DISTRICT UTTAR PRADESH

The goat is a vital milk and meat production source in India and contributes to the national and international economy. Goat production faces multiple challenges; one major problem is parasites leading to high mortality and economic losses. Nematode parasites are major problems to livestock globally, characterized clinically by enteritis, anaemia, emaciation, dehydration, and death. This study revealed the morphological identification of nematode parasites (Haemonchus sp., Oesophagostomum sp., and Trichuris sp.) in goats in the Lucknow region (India). Morphological identification was done by SEM (Scanning Electron Microscope) with the help of Souls in 1982. Scanning electron microscope exposed some species-specific characters, total body length of parasites, posterior region of Haemonchus having well-developed Copulatory Bursa (CB), spicules, Dorsal ray (DR) Anterior region of Haemonchus having cervical papillae (CP), vulval flap, knob, and cervical lamina. Oesophagostomum showed that the collar region on the mouth part and Buccal Capsule (BC) is surrounded by External Corona Radiate (ECR) and Internal Corona Radiate (ICR). Trichuris sp. was showed the anterior end vulva region of the female, and the posterior end of the male was spirally coiled and spicular sheath covered with minute spines (S).

Integrative taxonomy unveils a new species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from the southern portion of the Taihang Mountains in northern China, with the description of its complete mitogenome and an exploratory analysis of mitochondrial gene order as a taxonomic character.

A new species of Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from northern China is described on the basis of an integrative approach, involving morphology, karyology, histology, molecular distance, molecular phylogeny, and mitochondrial gene order. Here, we present the complete mitogenome of the new species Dugesia constrictiva Chen & Dong, sp. nov. This new species is mainly characterized by the presence of the following features: asymmetrical openings of the oviducts; large, cuboidal copulatory bursa; vasa deferentia opening through the ventro-lateral wall of the seminal vesicle; laterally compressed seminal vesicle; ventrally displaced ejaculatory duct, opening at the blunt tip of the penis papilla; long duct intercalated between seminal vesicle and diaphragm; chromosome complement diploid, with 16 metacentric chromosomes; mitochondrial gene order as follows: cox1-E-nad6-nad5-S2-D-R-cox3-I-Q-K-atp6-V-nad1-W-cox2-P-nad3-A-nad2-M-H-F-rrnS-L1-Y-G-S1-rrnL-L2-T-atp8-C-N-cob-nad4l-nad4. In triclads, mitochondrial gene order is considerably conserved between freshwater planarians and land flatworms, whereas it is variable between marine planarians and both freshwater and land flatworms. The secondary structures of tRNAs are all equipped with 4 arms, excepting tRNA S1 and tRNA S2, which lack the D arm and have excessively enlarged loops. Numerous transpositions of tRNA are present between D. constrictiva and its congeners. Mitochondrial gene arrangements may form a new, additional tool for taxonomic studies. The phylogenetic tree based on analysis of the mitochondrial genome basically corroborates current classification of the higher taxa of planarian flatworms.

Intersex Plays a Role in Microbial Homeostasis in the Brown Planthopper.

Simple SummaryRNAi-mediated knockdown of intersex in the newly emerged Nilaparvata lugens leads to abnormal expansion of the copulatory bursa by infection filled with bacteria. RNA-seq analysis shows a significant enrichment of immune defense genes responsive to bacteria in differentially expressed genes (DEGs). Moreover, inhibition of intersex expression by dsRNA treatment results in changes in the richness index of symbiotic microorganisms in copulatory bursa, fat body, and midgut of the planthopper. Specifically, significant changes are observed in the microbial community composition of the copulatory bursa. These findings reveal the function of intersex in maintaining microbial homeostasis in this insect, thereby providing insight to improve the pest control strategies.Insects harbor a wide variety of symbiotic microorganisms that are capable of regulating host health and promoting host adaptation to their environment and food sources. However, there is little knowledge concerning the mechanisms that maintain the microbial community homeostasis within insects. In this study, we found that the intersex (ix) gene played an essential role in maintaining microbial homeostasis in the brown planthopper (BPH), Nilaparvata lugens. Injection of the double-strand RNA targeting N. lugens ix (Nlix) into the newly emerged females resulted in abnormal expansion of the copulatory bursa of BPH after mating. Further observation by transmission electron microscopy (TEM) revealed that the abnormally enlarged copulatory bursa resulting from dsNlix treatment was full of microorganisms, while in contrast, the copulatory bursa of dsGFP-treated individuals stored a large number of sperm accompanied by a few bacteria. Moreover, RNA-seq analysis showed that the gene responses to bacteria were remarkably enriched in differentially expressed genes (DEGs). In addition, 16s rRNA sequencing indicated that, compared with control samples, changes in the composition of microbes presented in dsNlix-treated copulatory bursa. Together, our results revealed the immune functions of the Nlix gene in maintaining microbial homeostasis and combating infection in BPH.

Two new earthworms of the Pheretima sangirensis species group (Clitellata: Megascolecidae) from Mountain Province, Philippines.

Two new species of the genus Pheretima are described from Mt. Amuyao and Mt. Lamagan, Mountain Province, Philippines, namely Pheretima riparianensis sp. nov. and Pheretima bontocensis sp. nov. Both new species belong to the P. sangirensis species group characterized by having only one pair of spermathecal pores in 7/8. Pheretima riparianensis sp. nov. has distance between spermathecal pores 12 mm; copulatory bursae openings 0.11 circumference ventrally apart. Pheretima bontocensis sp. nov. has distance between spermathecal pores 1.4 mm; copulatory bursae openings 0.10 circumference ventrally apart.

Characterization of Filisoma argusum n. sp. (Acanthocephala: Cavisomatidae Meyer, 1932) infecting the spotted scat, Scatophagus argus (Linnaeus, 1766) from the Indian coast.

The present paper describes Filisoma argusum n. sp. (Cavisomatidae), an acanthocephalan parasite infecting the intestine of the spotted scat, Scatophagus argus (Linnaeus, 1766), in the south-west coast of India. The prevalence is 18% (mean intensity: 1.61 and abundance: 1-4 worms/host). Filisoma argusum n. sp. is morphologically characterized by a creamy-white, cylindrical, elongate, aspinose, and robust trunk; a collar-like neck; and a cylindrical proboscis with 18-20 longitudinal rows of hooks, with 19-22 hooks/row. Proboscis receptacle long, double-walled. Lemnisci digitiform, equal, longer than proboscis receptacle. Females 79.14 ± 33.69 × 0.593 ± 0.19 mm; males 32.62 ± 2.98 × 0.46 ± 0.071 mm. Males with four cement glands; bulbous muscular copulatory bursa with six digitiform rays. SEM studies revealed smooth hooks, sensory pits, and epidermal micropores. Histopathological changes at the site of parasite attachment included inflammation, hemorrhage, sloughing of epithelium, and detachment of mucosal layer of the intestine. In molecular and phylogenetic analyses, the parasite occupied an independent position within the Cavisomatidae clade with high bootstrap values for both ITS1-5.8S and ITS2, and mt-CO1 regions. Considering the morphologic and morphometric differences with previously described species of Filisoma along with its phylogenetic positioning, the present acanthocephalan is treated as a new species and the name Filisoma argusum n. sp. is proposed.

Integrative descriptions of two new species of Dugesia from Hainan Island, China (Platyhelminthes, Tricladida, Dugesiidae).

Two new species of the genus Dugesia (Platyhelminthes, Tricladida, Dugesiidae) from Hainan Island of China are described on the basis of morphological, karyological and molecular data. Dugesia semiglobosa Chen & Dong, sp. nov. is mainly characterized by a hemispherical, asymmetrical penis papilla with ventrally displaced ejaculatory duct opening terminally at tip of penis papilla; vasa deferentia separately opening into mid-dorsal portion of intrabulbar seminal vesicle; two diaphragms in the ejaculatory duct; copulatory bursa formed by expansion of bursal canal, lined with complex stratified epithelium, which projects through opening in bursa towards intestine, without having open communication with the gut; mixoploid chromosome complement diploid (2n = 16) and triploid (3n = 24), with metacentric chromosomes. Dugesia majuscula Chen & Dong, sp. nov. is mainly characterized by oviducts opening asymmetrically into female reproductive system; hyperplasic ovaries; expanded posterior section of bursal canal; vasa deferentia separately opening into mid-dorsal portion of seminal vesicle; asymmetrical penis papilla due to ventral course of ejaculatory duct, which has subterminal and dorsal opening at tip papilla; mixoploid chromosome complement diploid (2n = 16) and triploid (3n = 24); chromosomes metacentric. Apart from their anatomy, separate species status of the two new species is supported also by their genetic distances and by their positions in the phylogenetic tree. The sexualization process may have been induced by the lower temperatures, in comparison with their natural habitat, under which the worms were cultured in the laboratory.

The earthworm fauna of Palawan, Philippines with description of nineteen new pheretimoid species (Clitellata: Megascolecidae)

ABSTRACT We described 19 new species of pheretimoid earthworms in Palawan, Philippines. Of these, eight are Pheretima belonging to the Ph. darnleiensis group, characterised by having either four or five pairs of spermathecal pores located in 5/6–8/9. These were Pheretima ingentis sp. nov., Ph. palawanensis sp. nov., Ph. atongensis sp. nov., Ph. ascensa sp. nov., Ph. marinanaensis sp. nov., Ph. brookespointensis sp. nov., Ph. multicamera sp. nov., and Ph. hamadryades sp. nov. Seven are Polypheretima, of which Polypheretima victoriaensis sp. nov., Po. irawanensis sp. nov., Po. jenniferae sp. nov., Po. puertoprincesaensis sp. nov., Po. fleischmani sp. nov., and Po. mantalingahanensis sp. nov. belong to the Po. elongata group, characterised by having a pair of genital markings in xix, successive segments in line with the male pores, paired batteries of up to 28 spermathecae in vi and/or vii, and shallow copulatory bursae, while Po. zonadimidia sp. nov. is unique among all Polypheretima species in having a saddle-shaped clitellum and in having a pair of genital markings on xiv, xv, xvii and xix in line with the male pores. Two species are Amynthas, namely Am. magnaprostata sp. nov. of the Am. sieboldi group, characterised by having three pairs of spermathecal pores in 6/7–8/9 and a holandric male system, and Am. elnidoensis sp. nov. of the Am. minimus group, characterised by having a pair of spermathecal pores in 5/6. Also, two are Metaphire, namely Me. santalourdesensis sp. nov. of the Me. merabahensis group, characterised by having three pairs of spermathecal pores at 5/6–7/8, and Me. narraensis sp. nov. of the Me. peguana group, characterised by having three pairs of spermathecal pores in 6/7–8/9 and post-clitellar genital markings at 17/18 and 18/19. With thorough biological surveys in Palawan, we expect that more species will be discovered in this biogeographic faunal region. urn:lsid:zoobank.org:act:04B185DB-7D43-42B1-9497-C28B3228BDF0 urn:lsid:zoobank.org:act:23954AD0-3C7A-46D3-AD5A-BF8F50681338 urn:lsid:zoobank.org:act:A1B3ED85-A649-4692-A2E4-5A53D76236E1 urn:lsid:zoobank.org:act:1EFB06B6-3D92-40E8-B337-C09DAA342B57 urn:lsid:zoobank.org:act:CE333FA2-B3D8-4B65-B915-5328AF53D715 urn:lsid:zoobank.org:act:31851231-C527-4E50-AFD4-BF9AA22EAD12 urn:lsid:zoobank.org:act:105E5C1D-8BF6-444E-B4B0-EC511A155A49 urn:lsid:zoobank.org:act:3CA8628E-0458-49EE-8BE2-49A6143D39DC urn:lsid:zoobank.org:act:75AB66AC-7B43-4A7C-B0CE-089CEE28A8C3 urn:lsid:zoobank.org:act:26B59F17-9318-4853-958D-B758E699830F urn:lsid:zoobank.org:act:1E205842-3930-42A0-BB81-223358E21206 urn:lsid:zoobank.org:act:49EFE723-2123-4D7D-8430-6A4A61CFE13D urn:lsid:zoobank.org:act:29EB0027-BEDA-48CA-B7B8-AAFE19C0FD84 urn:lsid:zoobank.org:act:0DB1D5C3-C1D4-4581-8713-0C5E0C4346B2 urn:lsid:zoobank.org:act:CC6BC860-9CDA-46C7-9001-D5DC92E008E4 urn:lsid:zoobank.org:act:0F85D176-0F8B-4605-B08C-0371743D486C urn:lsid:zoobank.org:act:0B376B0E-7CA5-4BC2-BD3B-062BA8F2AAF4 urn:lsid:zoobank.org:act:5FBA6522-DA25-4606-99C9-315555E55BCF urn:lsid:zoobank.org:act:68FAA1DF-10AF-4BEA-8653-F2E88F2A026A

Amphibioplanidae: a new branch and family on the phylogenetic tree of the triclad flatworms (Platyhelminthes: Tricladida), represented by a species from Sardinian caves with a remarkable lifestyle

AbstractIn this study we document the phylogenetic position and the anatomical and ecological characteristics of a new taxon of cave-dwelling triclad flatworms. This species from the Mediterranean island of Sardinia (Italy) forms a separate branch on the phylogenetic tree of the planarians for which we proposed a new genus and placed it in a new family. Molecular analysis reveals a sister-group relationship between this new family, Amphibioplanidae, and the family Dimarcusidae of the suborder Cavernicola, together constituting the sister-group of the suborder Maricola. The new species Amphibioplana onnisi Stocchino & Sluys, sp. nov. is slender and furnished with an epidermis that is abundantly and uniformly provided with cilia and rhabdites. The pharynx presents an oesophageal projection pointing into the pharynx lumen. Ovaries are located far behind the brain. A relatively long common oviduct opens into the diverticulum of the bursal canal. The probursal copulatory bursa is lined with a highly vacuolated, syncytial epithelium. The habitat of this species is formed by groundwater in microcrevices of the epikarst and temporary cave pools, but the animals can survive in a basically terrestrial environment, thus exhibiting an amphibious lifestyle. Some tentative scenarios are discussed for the evolution of the new taxon and for the presence of the new species in three separate caves in Sardinia.

The taxonomic status of Skrjabinalius guevarai Gallego & Selva, 1979 (Nematoda: Pseudaliidae) and the synonymy of Skrjabinalius Delyamure, 1942 and Halocercus Baylis & Daubney, 1925.

Within the cetacean lungworm family Pseudaliidae Raillet & Henry, 1909, the distinction between the two genera of the subfamily Halocercinae Delamure, 1952, i.e. Halocercus Baylis & Daubney, 1925 and Skrjabinalius Delyamure, 1942, is principally based on the structure and shape of the male copulatory bursa. In species of Halocercus, the bursa is unlobed, whereas in the two species included in Skrjabinalius, S. cryptocephalus Delyamure, 1942 and Skrjabinalius guevarai Gallego & Selva, 1979, the bursa is described as clearly lobed. During a parasitological analysis of cetaceans from the Spanish Mediterranean, we collected a number of specimens of S. guevarai with variable levels of bursal lobulation, including individuals with unlobed bursae. Examination of voucher specimens of the type-species of Halocercus, H. delphini Baylis & Daubney, 1925, collected from cetaceans in the North-East Atlantic revealed the same variations in bursal shape, and the same arrangement of bursal rays and papillae. A morphometric comparison did not reveal substantial differences between both species. Moreover, Maximum Likelihood and Bayesian Inference analyses of the second internal transcribed spacer (ITS2) sequences of 11 specimens of S. guevarai and one of H. delphini grouped both species together, regardless of bursal shape, in a highly supported clade within the Pseudaliidae. Accordingly, we consider S. guevarai as a junior synonym of H. delphini. The great variability found in bursal lobulation in the type-species of Halocercus invalidates the use of this trait as a genus-level diagnostic character and, therefore, Skrjabinalius should also be considered synonymous with Halocercus.

Intestinal Flukes Recovered from a Herring Gull, Larus argentatus, in the Republic of Korea.

Trematode specimens were collected from the intestine of a herring gull, Larus argentatus, which was found in a critical condition on the shore of a small island (Yubu-do, Seocheon-gun, Chungcheongnam-do) located at the western coast of the Korean peninsula. Total 11 specimens of intestinal flukes, including 3 Cryptocotyle lingua (Heterophyidae), 1 Himasthla alincia (Echinostomatidae), 5 Cardiocephaloides medioconiger (Strigeidae), and 2 Diplostomum spathaceum (Diplostomidae), were recovered. C. lingua was morphologically characterized by the presence of a large ventrogenital apparatus and 2 obliquely tandem testes. H. alincia had an elongated body and a head collar equipped with 31 collar spines. C. medioconiger had a bisegmented body and a voluminous copulatory bursa containing the seminal vesicle and ejaculatory duct. D. spathaceum also had a bisegmented body and its vitellaria extended up to the anterior border of the tribocytic organ. It is of note that C. lingua is potentially zoonotic that can occur in birds and humans. Three of them, i.e., C. lingua, C. medioconiger, and D. spathaceum, are new trematode fauna in Korea. Studies on trematode fauna of migratory birds should be continued in Korea.