The discovery of Moniliformis saudi (Acanthocephala: Moniliformidae) in the Algerian hedgehog Atelerix algirus in Malta: morphological, molecular, and metal analyses.

The acanthocephalan Moniliformis saudi Amin, Heckmann, Mohammed, Evans, 2016 was originally described from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg) in central Saudi Arabia. The distribution of P. aethiopicus extends to North Africa and west to Mauritania. Moniliformis saudi was recently found in the Algerian hedgehog Atelerix algirus (Lereboullet) in Malta. The distribution of A. algirus is restricted to the North African and east Iberian Mediterranean coast and associated islands. Both host species cohabit and share the same feeding grounds in northern Algeria where common infections appear to take place. The morphology of specimens from both acanthocephalan populations was similar, with minor variations mostly related to the relatively larger Maltese specimens especially the trunk and the male reproductive system. Taxonomic features like the cone-shaped anterior trunk, size and formula of proboscis and hooks, the receptacle, size and shape of eggs, anatomy of the apical proboscis sensory pores, and the stellate body wall giant nuclei were, however, practically identical. SEM and microscope images of specimens of the Maltese population emphasize their qualitative characteristics such as the degree of the extreme spiral muscle development and the development of the posterior nucleated pouches of the proboscis receptacle. Proboscis hooks of specimens from both the Maltese and the Saudi populations had similarly high levels (percent weights) of calcium, moderate levels of phosphorus, and minimal levels of sulfur, magnesium and sodium marking the diagnostic value of the Energy Dispersive x-ray analysis in species recognition. Newly generated partial sequences of the 18S ribosomal RNA and cytochrome C oxidase subunit 1 (Cox1) of the mitochondrial gene were generated from M. saudi from Malta. Moniliformis saudi from Malta, when compared with other available sequences of the same species isolates available in the GenBank database, formed a strongly supported clade with other congeners. The comparison of the molecular profiles of specimens from populations in Malta, Spain, and Saudi Arabia shows no or low genetic variation between them. Ultimately, we provide a morphological and molecular description of a new population of M. saudi from a new host species in a new geographical location, vastly exceeding the originally described ones from Saudi Arabia. A Cox 1 haplotype network inferred with 10 sequences revealed the presence of eight haplotypes, one of which was shared between the populations of Malta and Spain of M. saudi.

First molecular description of Neorhadinorhynchus nudus (Acanthocephala: Cavisomidae) from fish in the pacific coast of Vietnam, with notes on biogeography.

Neorhadinorhynchus nudus (Harada, 1938) Yamaguti, 1939 (Cavisomidae) was morphologically described from the frigate tuna Auxis thazard (Lacépède) (Scombridae) in Nha Trang, Pacific south Vietnam. Females of N. nudus were fully described for the first time in the Pacific. Its original inadequate description as Rhadinorhynchus nudus (Harada, 1938) was corrected in material from Fiji Island, the Red Sea and Pacific Vietnam and errors in the text and line drawings of Harada were repeated in subsequent major publications where it underwent considerable nomenclature changes. New descriptive and biogeographical notes are included. We also provided here the molecular characterization of the nuclear gene (18S) and the mitochondrial cytochrome c oxidase subunit 1 (cox1) sequence data of N. nudus. Furthermore, to elucidate the phylogenetic relationship of N. nudus within the family Cavisomidae and with other isolates were performed incorporating nuclear (18S) and mitochondrial (cox1) sequence data using maximum likelihood (ML) and Bayesian inference (BI). The phylogenetic results showed that N. nudus has a relationship with other isolates of the same species and the median-joining network showed the pattern of haplotypes that reflected the structure of the populations.

Evaluating energy dispersive X-ray analysis (EDXA) as a diagnostic tool in acanthocephalan taxonomy as evidenced in Palaeacanthocephala and Archiacanthocephala.

We have examined the anterior and middle hooks of many specimens of 3 species of acanthocephalans from Ukraine including (1) adults of Acanthocephalus ranae (Schrank, 1788) Lühe, 1911 from 4 species of frogs in 6 geographical locations, (2) adults of Southwellina hispida Van Cleave, (1925) Witenberg, 1932 from 3 species of birds in 2 geographical locations, and (3) adults and cystacanths of Sphaerirostris picae (Rudolphi, 1819) Golvan, 1956 from 1 species of birds, 1 species of lizards, and 1 species of mammals in 2 geographical locations, to analyze their Ca, S, and P spectra using Energy dispersive x_ray analysis (EDXA), and account for their intraspecific variabilities. Adults of each of A. ranae from frogs and adults of S. hispida from birds each showed comparable metal spectra irrespective of host species and geography, especially when metal weight percent figures are averaged. In S. picae, 5 adult specimens from birds had comparable spectra but the cystacanth from hedgehog, a mammal, had particularly dissimilar pattern with much lower levels of P and Ca. We have also studied the EDXA patterns in anterior, middle and posterior hooks of cystacanths, juveniles, and adults of Moniliformis kalahariensis Meyer, 1931 much lower levels of P and Ca. in South Africa, Botswana, and India collected from their invertebrate intermediate and vertebrate definitive hosts to examine the EDXA profiles. Our conclusions were comparable to those reached from the Ukrainian material with the additional emphasis on the importance of using the same developmental stage in comparing interspecific EDXA profiles. The importance of the stability of the levels of S in various developmental stages across the host species barrier is exemplified by its relationship to the genetically based protein synthesis, which gives credibility to the usage of EDXA for diagnostic purposes. Our findings show that EDXA is a useful tool to characterize the taxonomic identity of species of Acanthocephala providing that (1) a population of a number of individual specimens are analyzed and average weight percent figures of metals are used for comparisons, and (2) comparisons are made using specimens of the same developmental stage and from hosts of the same class of vertebrate. When these conditions are met, the metal spectra for each species will prove valid for diagnostic purposes.

The Bergen Facebook Addiction Scale: its psychometric properties and invariance among women with eating disorders.

OBJECTIVE: Facebook addiction is increasing, giving rise to limited real-life social networks, loneliness, poor work and academic performance, psychopathology, and low well-being. Facebook entails numerous factors that increase the risk for disordered eating attitudes and behaviors (e.g., use time and Facebook activities such as social grooming and photo sharing). This study aimed to evaluate the psychometric properties of the Bergen Facebook Addiction Scale (BFAS) among patients with eating disorders (EDs) given lack of validation of Facebook addiction measures in this population. METHODS: A cross-sectional study involving 123 inpatient and outpatient women with EDs (Mean age = 27.3, SD = 10.6, range = 14-59 years) used confirmatory factor analysis (CFA), multigroup CFA, structural equation modeling (SEM), Spearman's rho Spearman's analysis, McDonald's Omega (ω), Cronbach's alpha (α), and item-total correlations to examine the structure, invariance, criterion validity, reliability, and discriminant validity of the BFAS. RESULTS: Correlating the residuals of items 2, 3, and 5 resulted in an excellent fit of a one-factor structure of the BFAS (χ2(7) = 8.515, p = .289, CFI = .998, TLI = .996, RMSEA = .042, SRMR = .0099). The BFAS was invariant at the configural, metric, and scalar levels across groups of EDs, age, education, and marital status. High values of ω and α (.96) as well as item-total correlations (.851-.929) indicated excellent reliability and high discrimination index of the BFAS.  Criterion validity is noted by strong positive correlation with the Six-item Internet Addiction Test (S-IAT, r = .88) and SEM using the S-IAT to predict the BFAS (χ2(49) = 103.701, p = .001, CFI = .975, TLI = .966, RMSEA = .096, SRMR = .0317).. CONCLUSION: The BFAS is a reliable unidimensional measure. Its high discrimination index and invariance across different groups make it useful for detecting Facebook addiction among patients with ED.

New morphological and molecular perspectives about Macracanthorhynchus hirudinaceus (Acanthocephala: Oligacanthorhynchidae) from wild boar, Sus scrofa Linn., in Ukraine.

We make new morphological observations not previously reported for the old acanthocephalan Macracanthorhynchus hirudinaceus (Pallas, 1781) Travassos, 1917, described for the first time about 240 years ago. Our specimens were collected from the wild boar, Sus scrofa Linn., in Ukraine in 2005. We provide comparative morphometrics with other populations from Ukraine, Union of Soviet Socialist Republics, Europe, Brazil and the United States of America. Our specimens from the Ukraine had the smallest trunk (110-120 mm long), longest and thickest hooks, with the third hook being the largest, largest eggs, and a proboscis wider than long. We document the morphology of the proboscis, apical organ, hooks, hook roots, sensory pores, micropores, and eggs with scanning electron microscopy for the first time. We also provide chemical analysis of hooks and eggs using energy-dispersive X-ray analysis, discuss its micropores, and provide a new molecular profile based on 18S rDNA from a European population for the first time. Edge of hook tips feature high levels of calcium and phosphorous but the high level of sulphur is mostly found in the cortical layer of eggs. One new partial 18S rDNA sequence (482 nt length) was generated from an adult specimen of M. hirudinaceus. We present the first 18S rDNA published sequence for this cosmopolitan acanthocephalan obtained from Europe. The amplified region corresponded to the approximate middle region of the small subunit ribosomal ribonucleic acid gene, which is ~1800 nt in length. This molecular contribution is especially valuable in light of the extreme scarcity of genetic information about species of Macracanthorhynchus and of the family Oligacanthorhynchidae as a whole.

Descriptions of two new acanthocephalans (Rhadinorhynchidae) from marine fish off the Pacific coast of Vietnam.

Two rhadinorhynchid acanthocephalans are described from marine fishes off the Pacific coast of Vietnam. Sclerocollum neorubrimaris n. sp. (Gorgorhynchinae Van Cleave & Lincicome, 1940) is described from the spine-foot rabbitfish Siganus guttatus (Bloch) (Siganidae) off Nha Trang. The new species is similar to the type-species, Sclerocollum rubrimaris Schmidt & Paperna, 1978 in most measurements and counts but has a posterior cephalic ganglion, a sub-ventral female gonopore, and one dorsal paravaginal filament bundle. In S. rubrimaris, the cephalic ganglion is near the middle of the receptacle, the female gonopore is terminal with two paravaginal filament bundles. The new species is distinguished from three other species of Sclerocollum Schmidt & Paperna, 1978 in proboscis hook formulas and the position of the female gonopore and cephalic ganglion. The issue of the importance of the position of the cephalic ganglion at the generic and sub-generic levels in the Acanthocephala is discussed. Females of Australorhynchus multispinosus n. sp. (Gorgorhynchinae) are described from the red cornetfish Fistularia petimba Lacépède off Nha Trang in the Pacific south. It is distinguished from the only other species of the genus, Australorhynchus tetramorphacanthus Lebedev, 1967, by having more trunk spines extending beyond the level of the proboscis receptacle and a smaller proboscis with considerably fewer hooks.

Morphological variability in Acanthocephaloides irregularis Amin, Oguz, Heckmann, Tepe & Kvach, 2011 (Acanthocephala: Arhythmacanthidae) from the European sea bass, Dicentrarchus labrax (L.) (Moronidae) in Bizerte Lagoon, Tunisia.

Specimens of an arhythmacanthid acanthocephalan were recovered from the European sea bass Dicentrarchus labrax (L.) (Perciformes: Moronidae) in Bizerte Lagoon, northern Tunisia. The specimens collected showed high morphological similarities to Acanthocephaloides irregularis Amin, Oguz, Heckmann, Tepe & Kvach, 2011, recovered from four species of marine fishes in the Gulf of Odessa and Sukhyi Lyman off the Ukrainian Black Sea coast. Light and scanning electron microscopy revealed some morphological differences from the Black Sea specimens in trunk spine distribution, number of proboscis hooks in males (4 instead of 5), and lack of demonstrable trunk collar. These variations suggest that our specimens may only be a morphotype of A. irregularis with new host and locality records. A comparison between our specimens and those of the original description clarifies the possible reasons of this intraspecific morphological variability.

Morphological and molecular descriptions of Moniliformis saudi sp. n. (Acanthocephala: Moniliformidae) from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg) in Saudi Arabia, with a key to species and notes on histopathology.

A new acanthocepohalan species, Moniliformis saudi sp. n. is described from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg), in central Saudi Arabia. Fourteen other valid species of Moniliformis Travassos, 1915 are recognised. The new species of Moniliformis is distinguished by having a small proboscis (315-520 µm long and 130-208 µm wide) with two apical pores, 14 rows of 8 hooks each and small hooks, thre largest being 25-31 µm long anteriorly. Distinguishing features are incorporated in a dichotomous key to the species of Moniliformis. The description is augmented by scanning electron microscopical (SEM) observation and DNA analysis of nuclear (18S rRNA) and mitochondrial (cytochrome oxidase subunit 1; cox1) gene sequences. Attached worms cause extensive damage to the immediate area of attachment in the host intestine. This includes tissue necrosis and blood loss due to damage to capillary beds. Worms also obstruct essential absorbing surfaces.

Morphological and molecular description of Tenuisentis niloticus (Meyer, 1932) (Acanthocephala: Tenuisentidae) from Heterotis niloticus (Cuvier) (Actinopterygii: Arapaimidae), in Burkina Faso, with emendation of the family diagnosis and notes on new features, cryptic genetic diversity and histopathology.

Specimens described as Rhadinorhynchus niloticus Meyer, 1932 (Rhadinorhynchidae) from two male specimens collected from Heterotis niloticus (Cuvier) in the Egyptian Nile were later redescribed in the genus Tenuisentis Van Cleave, 1936 (Tenuisentidae) based on 12 specimens collected from the same host species in the White Nile. That redescription basically distinguished the two genera based on five traits but did not actually provide a formal description. His account left out information about cerebral ganglion, lemnisci, some reproductive structures, eggs, proboscis hook dissymmetry and roots, size of trunk and a few other structures. We provide (i) the first complete description of this species enhanced by SEM, molecular, and histo-pathological studies; (ii) expand the existing descriptions; (iii) correct questionable accounts advanced by Van Cleave on the cement gland and the hypodermal giant nuclei; and (iv) add descriptions of new features such as the para-receptacle structure which we also report from Paratenuisentis Bullock & Samuel, 1975, the only other genus in Tenuisentidae Van Cleave, 1936. The subsequent description of a few more specimens from the same host collected in Mali was more informative yet incomplete and at variance with our specimens from Burkina Faso. Genetic divergence and phylogenetic analyses of mitochondrial (cytochrome oxidase c subunit I; COI) and nuclear (18S ribosomal RNA) gene relationships uncovered a cryptic species complex containing two lineages. Based on our studies, the family diagnosis is emended. The acanthocephalan causes damage to the host intestine as depicted in histopathological sections. The invading worm can extend from the mucosal layer to the muscularis externa of the host with subsequent tissue necrosis, villi compression, haemorrhaging and blood loss.

The description of Centrorhynchus globirostris n. sp. (Acanthocephala: Centrorhynchidae) from the pheasant crow, Centropus sinensis (Stephens) in Pakistan, with gene sequence analysis and emendation of the family diagnosis.

A new species of Centrorhynchus (Centrorhynchidae) with receptacle insertion at the posterior third of the proboscis is described from the pheasant crow Centropus sinensis (Stephens) (Cuculidae) in Pakistan. Centrorhynchu sglobirostris n. sp. is similar to the 98 other known species of Centrorhynchus Lühe, 1911 in having long cylindrical trunk with anterior dilation and transverse anastomoses of the secondary lacunar vessels. However, specimens of C. globirostris differ from all other species of the genus by having a unique globular proboscis not divided into anterior proboscis with rooted hooks and posterior proboscis with rootless spines. Posterior hooks of C. globirostris emerge at the level of the receptacle insertion and are uniquely fully rooted. Sequencing and phylogenetic analysis of C. globirostris 18S and 28S ribosomal RNA genes reveals the genetic and evolutionary relationships between C. globirostris and other members of Centrorhynchidae which have representative orthologs in public databases. Comparison to known acanthocephalans confirms appropriate inclusion in the genus Centrorhynchus.

The Description of Neoechinorhynchus miniovalis n. sp. (Acanthocephala: Neoechinorhynchidae) from the Mudskipper Boleophthalmus dussumieri Valenciennes (Gobiiformes: Oxudercidae) in Shatt Al-Basrah Canal Southern Iraq.

PURPOSE: The aim of this article is to describe a new and unusual species of Neoechinoprhynchus Stiles & Hassall, 1905 from the Arabian Gulf coast off Iraq. METHODS: Routine methods for examination of fish hosts and recovery of acanthocephalean parasites were followed. Parasites were cleaned, relaxed overnight in refrigerated water then fixed in cold 70% ethanol. Standard procedure for staining, dehydration, clearing in xylene and mounting in Canada balsam was followed. RESULTS: Neoechinorhynchus miniovalis n. sp. is described from five whole-mounted specimens collected from the mudskipper Boleophthalmus dussumieri Valenciennes (Oxudericidae) captured in Shatt Al-Basrah Canal, Iraq in 2008. It is distinguished from other species of Neoechinorhynchus Stiles and Hassall, 1905 by a combination of the following diagnostic characters: very small ellipsoid trunk with tapering posterior end and correspondingly small size organs; body wall with similar thickness dorso-ventrally; proboscis wider than long with long anterior hooks having prominent roots; hooks in second and third circles much smaller and rootless; receptacle 5-6 times as long as proboscis with a triangular cephalic ganglion at its base; no para-receptacle structure; lemnisci relatively long and equal, not reaching anterior testis; all male reproductive structures contiguous in posterior two-thirds of trunk; testes equatorial and much wider than long; anterior testis smaller than posterior testis; large syncytial cement gland with six giant nuclei; cement reservoir adjacent to anterior end of sperm vesicle adjacent to Saefftigen's pouch. No sexual dimorphism except that the trunk is more rounded in females than in males. The female reproductive system is about one-third as long as the trunk with the selective apparatus in two positions and uterine bell angulating ventrad. Female lemnisci are longer than in males. Comparisons with worldwide and North American-related species that have partially similar features are made. CONCLUSIONS: The finding of Neoechinorhynchus miniovalis n. sp. with unusual small body and wide ellipsoid shape acanthocephalan is considered the first acanthocephalan species belonging to Neoechinorhynchus reported from Palearctic region compared to similar seven species reported only from Neotropical (three species), Nearctic regions (two species), far east (one species) and oriental (one species).

Neglected Developmental Hip Dysplasia Treated With External Iliofemoral Distraction, Open Reduction, and Pelvic Osteotomy: Eleven-Year Follow-Up.

Neglected untreated developmental hip dysplasia can result in severe deformities and functional disabilities. This report describes the treatment and 11-year follow-up of a patient who underwent the procedure in two stages. At the time of treatment, the patient was 7 years of age and was diagnosed with acetabular dysplasia and neglected right hip dysplasia. A stepwise treatment approach, including gradual distraction of the iliofemoral joint, open reduction, and pelvic osteotomy, was performed. Subsequent postoperative rehabilitation and regular follow-up assessments were performed over 11 years. The long-term results indicated notable improvements in hip joint congruency, functional range of motion, and overall quality of life. Early diagnosis and appropriate intervention are crucial for patients with developmental hip dysplasia, and the treatment methods described here are effective.

Antimicrobial resistance of Pseudomonas aeruginosa: navigating clinical impacts, current resistance trends, and innovations in breaking therapies.

Pseudomonas aeruginosa, a Gram-negative bacterium, is recognized for its adaptability and opportunistic nature. It poses a substantial challenge in clinical settings due to its complicated antibiotic resistance mechanisms, biofilm formation, and capacity for persistent infections in both animal and human hosts. Recent studies revealed a potential zoonotic transmission of P. aeruginosa between animals, the environment, and human populations which highlights awareness of this microbe. Implementation of the One Health approach, which underscores the connection between human, animal, and environmental health, we aim to offer a comprehensive perspective on the current landscape of P. aeruginosa management. This review presents innovative strategies designed to counteract P. aeruginosa infections. Traditional antibiotics, while effective in many cases, are increasingly compromised by the development of multidrug-resistant strains. Non-antibiotic avenues, such as quorum sensing inhibition, phage therapy, and nanoparticle-based treatments, are emerging as promising alternatives. However, their clinical application encounters obstacles like cost, side effects, and safety concerns. Effectively addressing P. aeruginosa infections necessitates persistent research efforts, advancements in clinical development, and a comprehension of host-pathogen interactions to deal with this resilient pathogen.

The description of Mediorhynchus africanus n. sp. (Acanthocephala: Gigantorhynchidae) from galliform birds in Africa.

Mediorhynchus africanus n. sp. is described from specimens collected from the helmeted guinea fowls, Numida meliagris Linn. 1758 in Kruger National Park and elsewhere in subSaharan Africa from the same and other galliform birds. These specimens were previously assigned to Mediorhynchus gallinarum Bhaleroa (Proc Zool Soc Lond Ser B Syst Morph 107:199-203, 1937) described from chickens, Gallus gallus L. in India and subsequently reported from other Asian countries. The identification of the African forms as M. gallinarum was based on similarities in the structure and measurements of the proboscis, proboscis armature and receptacle, lemnisci, and reproductive organs. A detailed study of specimens from South Africa and descriptions reported from elsewhere in Africa revealed marked differences that clearly distinguish the African material as new species. The African specimens are pseudo-segmented and flattened, the proboscis has two prominent apical pores, sensory pits are prevalent throughout the trunk, the posterior end of the female is broad with dorso-terminal dome-like extension opposite the subterminal gonopore, and the eggs are large. The Asian specimens from Indonesia and elsewhere are cylindrical and non-segmented, the proboscis lacks prominent apical pores, sensory pits are rare on the trunk, the posterior end of the female is pointed with a terminal gonopore, and the eggs are markedly smaller. We used DNA sequence from one mitochondrial gene (cytochrome oxidase subunit I) and one nuclear gene (18S ribosomal RNA) to infer the phylogenetic relationships of M. africanus and M. gallinarum and selected Acanthocephala. Medioryhnchus is monophyletic and M. africanus and M. gallinarum are allopatric sister species (9.7% sequence divergence). All findings indicate that M. africanus should be ranked as a separate species.

The morphology and histopathology of Nephridiacanthus major (Acanthocephala: Oligacanthorhynchidae) from hedgehogs in Iran.

The morphology of Nephridiacanthus major (Bremser 1811 in Westrumb 1821) Golvan, 1962 collected from the long-eared hedgehog Hemiechinus auritus (Gmelin 1770) and the Eastern European hedgehog Erinaceus concolor Martin, 1838 (Erinaceidae) is described using SEM for the first time. This acanthocephalan was previously described from hedgehogs in Europe, Asia, and Africa. Measurements of specimens from Iran, Bulgaria, Germany, Central Asia, Morocco, and Egypt show considerable variations in the size of the trunk, proboscis, proboscis hooks and receptacle, and eggs. The SEM studies add new perspectives to its morphology. Features observed for the first time include the near terminal position and shape of the female gonopore and orifice, among others. Histopathological studies for this species are reported for the first time. Tissue sections show extensive damage near the proboscis with hemorrhaging and formation of collagenous connective tissue, compression of the intestinal mucosa, obstruction of intestinal lumen, and extensive necrosis of host epithelial tissue.

The description and histopathology of Leptorhynchoides polycristatus n. sp. (Acanthocephala: Rhadinorhynchidae) from sturgeons, Acipenser spp. (Actinopterygii: Acipenseridae) in the Caspian Sea, Iran, with emendation of the generic diagnosis.

Of the three known species of Leptorhynchoides Kostylew 1924, two are reported from North American fishes: Leptorhynchoides aphredoderi Buckner and Buckner 1976 and Leptorhynchoides thecatus (Linton 1891) Kostylew 1924. The third species, Leptorhynchoides plagicephalus (Westrumb 1821) Kostylew 1924, is commonly found in the Caspian and Black Sea from at least four species of sturgeons including Acipenser stellatus Pallas 1771 and the Acipenser nudiventris Lovetzsky 1828 from which Leptorhynchoides polycristatus n. sp. was found. No taxonomic work has been reported for L. plagicephalus for the last 90 years. L. polycristatus n. sp. can be readily confused with L. plagicephalus because of many superficial similarities. Such similarities include the general shape of the trunk, proboscis, and organ systems. However, L. polycristatus is clearly distinguished from the other three species primarily by having (1) 19-20 proboscis hooks per row; (2) the shortest hooks are anterior and the longest at the middle; the opposite is true in L. plagicephalus; (3) with a cuticular collar enveloping the base of the proboscis hooks; (4) the surface of its proboscis hooks is ribbed; (5) with a broad collar of multiple rectangular cuticular crests encircling the anterior end of the trunk; this is the only member of Leptorhynchoides with such a structure; (6) with many large ovoid uninucleated cells in the subcuticular layer of the trunk; (7) with paired glandular clusters near the male reproductive opening and of suction cup-like sensory structures on the bursa; (8) with dorsoventral ligament across the vagina; (9) cement glands are in a cluster of eight arranged in two horizontal tiers of four glands each; (10) with female gonopore near terminal; (11) with structures interpreted as possible microtriches on the surface of the trunk; (12) and with thinner eggs. L. polycristatus caused extensive histopathological damage to host intestinal layers. The armed proboscis invades and attaches to the host mucosa causing villi compression and necrosis of the epithelial lining with subsequent hemorrhaging and granulocyte migration. No encapsulation of the acanthocephalan is visible, and the worm can migrate deep into the smooth muscle layers of the muscularis extrema. The presence of L. polycristatus in the lumen of the host intestine obstructs and damages the absorbing surface of the host affecting the nutritional potential. Dead, necrotic host epithelial tissue and remnants of villi and crypts are visible.

Classification of the acanthocephala.

In 1985, Amin presented a new system for the classification of the Acanthocephala in Crompton and Nickol's (1985) book 'Biology of the Acanthocephala' and recognized the concepts of Meyer (1931, 1932, 1933) and Van Cleave (1936, 1941, 1947, 1948, 1949, 1951, 1952). This system became the standard for the taxonomy of this group and remains so to date. Many changes have taken place and many new genera and species, as well as higher taxa, have been described since. An updated version of the 1985 scheme incorporating new concepts in molecular taxonomy, gene sequencing and phylogenetic studies is presented. The hierarchy has undergone a total face lift with Amin's (1987) addition of a new class, Polyacanthocephala (and a new order and family) to remove inconsistencies in the class Palaeacanthocephala. Amin and Ha (2008) added a third order (and a new family) to the Palaeacanthocephala, Heteramorphida, which combines features from the palaeacanthocephalan families Polymorphidae and Heteracanthocephalidae. Other families and subfamilies have been added but some have been eliminated, e.g. the three subfamilies of Arythmacanthidae: Arhythmacanthinae Yamaguti, 1935; Neoacanthocephaloidinae Golvan, 1960; and Paracanthocephaloidinae Golvan, 1969. Amin (1985) listed 22 families, 122 genera and 903 species (4, 4 and 14 families; 13, 28 and 81 genera; 167, 167 and 569 species in Archiacanthocephala, Eoacanthocephala and Palaeacanthocephala, respectively). The number of taxa listed in the present treatment is 26 families (18% increase), 157 genera (29%), and 1298 species (44%) (4, 4 and 16; 18, 29 and 106; 189, 255 and 845, in the same order), which also includes 1 family, 1 genus and 4 species in the class Polyacanthocephala Amin, 1987, and 3 genera and 5 species in the fossil family Zhijinitidae.

Redescription of Illiosentis cetratus Van Cleave, 1945 (Acanthocephala: Illiosentidae) from Menticirrhus undulatus (Girard) in California, with notes on Illiosentis furcatus from Peru.

Illiosentis Van Cleave et Lincicome, 1939 initially included two species: Illiosentis furcatus Van Cleave et Lincicome, 1939 found in the West Atlantic from Cape Cod in Massachusetts, USA to northern Argentina and Illiosentis cetratus Van Cleave, 1945 with restricted distribution in the Pacific coast of southern California. We are reporting I. furcatus from Peru for the first time and describe a population of I. cetratus from the California corbina, Menticirrhus undulatus (Girard), from southern California. The proboscis hook formula was 14 longitudinal rows for I. furcatus of 18-23 hooks each compared to 16 rows of 19-24 hooks each reported by Van Cleave (1945). We complete the inadequate description of I. cetratus with new information on sexual differentiation in the length of the trunk, dorsal vs. ventral hooks, hook roots, trunk spines, two types of anterior recurved rooted hooks vs. posterior rootless straight hooks, measurements of dorsal and ventral hooks and spines, shape of hook roots, terminal position of the female gonopore, and of position of the cephalic ganglion at the anterior margin of the trunk. We also include new details of the reproductive system in both sexes including Saefftigen's pouch and cement gland ducts. We present new SEM and light microscope images. The Energy Dispersive X-ray analysis (EDXA) shows a high level of sulfur in anterior, middle and posterior hooks in various hook sites, as well as spectra of hook tips with a higher relative concentration of sulfur compared to other hook sites. For the placement of I. cetratus, phylogenetic analysis of sequences of three molecular markers, 18S, 28S rRNA and mitochondrial cox 1 genes, was performed with other related available sequences. The resulting analysis illustrated that I. cetratus was nested within a separate clade along with species of two genera, Dentitruncus truttae Sinzar, 1955 and Neotegorhynchus cyprini Lisitsyna, Xi, Orosová, Barcák et Oros, 2022 represented our species of Illiosentis separate from species of Tegorhynchus Van Cleave, 1921 (as also according to the morphology) with which the Illiosentis species were previously synonymised.

Review of the concept of Profilicollis Meyer, 1931 with a description of Profilicollis rancoensis n. sp. (Acanthocephala: Polymorphidae) from the freshwater crab, Aegla abtao Schmitt, 1942 (Decapoda: Anomura) in Chile, with a key to congeneric species.

Profilicollis rancoensis n. sp. is the tenth species of Profilicollis Meyer, 1931 which includes 9 other species mostly known from marine decapod crabs and shore birds. Cystacanths of P. rancoensis are described from the dominant freshwater crab Aegla abtao in Ranco Lake, Chile and are morphologically distinguished from cystacanths of the 9 other species based on a combination of 4 characters. These are body size, number of proboscis hook rows, number of hooks per row, and length of the largest anterior 2-4 hooks. Male and female cystacanths of P. rancoensis are 2.10-3.33 mm long having an ovoid proboscis with 14 rows of 6-7 hooks per row, with the largest anterior 2-4 hooks being 105-110 micrometers long; the anterior trunk has many small spines in 70-80 concentric rings, each with 50-60 spines around them; hook roots are simple, directed posteriorly, about as long as the blades anteriorly with unremarkable anterior manubria; the cephalic ganglion are in mid-receptacle just anterior to the level of the anterior trunk; the lemnisci are long and slender; the testes are in the anterior trunk, posterior trunk, or one in each; the primordia of 2 tubular cement glands are evident; strong bundles of fibers link the anterior and posterior trunk; and the posterior trunk has a corrugated surface cuticula. Molecular analysis (COI and 18S) sequences coincided with the morphology and support its taxonomy. The phylogenetic profile revealed that P. rancoensis n. sp. fell into the Profilicollis clade. Both sequences showed low genetic variation, and three different haplotypes were found. The new species was more closely related to P. botulus (Van Cleave, 1916) Witenberg, 1932 than to other Profilicollis species.

Title: Révision du concept de Profilicollis Meyer, 1931 avec la description de Profilicollis rancoensis n. sp. (Acanthocephala, Polymorphidae) du crabe d'eau douce Aegla abtao Schmitt, 1942 (Decapoda, Anomura) au Chili, avec une clé des espèces congénères. Abstract: Profilicollis rancoensis n. sp. est la dixième espèce de Profilicollis Meyer, 1931 qui comprend neuf autres espèces principalement connues de crabes décapodes marins et d'oiseaux de rivage. Les cystacanthes de P. rancoensis sont décrits chez le crabe d'eau douce dominant Aegla abtao dans le lac Ranco, au Chili et se distinguent morphologiquement des cystacanthes des neuf autres espèces sur la base d'une combinaison de quatre caractères. Il s'agit de la taille du corps, du nombre de rangées de crochets du proboscis, du nombre de crochets par rangée et de la longueur des 2 à 4 crochets antérieurs les plus grands. Les cystacanthes mâles et femelles de P. rancoensis mesurent de 2,10 à 3,33 mm de long et ont une trompe ovoïde avec 14 rangées de 6 à 7 crochets par rangée, les 2 à 4 crochets antérieurs les plus grands mesurant 105 à 110 micromètres de long ; le tronc antérieur a de nombreuses petites épines en 70-80 anneaux concentriques chacun avec 50-60 épines ; les racines des crochets sont simples, dirigées vers l'arrière, à peu près aussi longues que les lames vers l'avant avec une manubrie antérieure sans particularité ; les ganglions céphaliques sont au milieu du réceptacle juste en avant du niveau du tronc antérieur ; les lemnisques sont longs et minces ; les testicules sont dans le tronc antérieur, le tronc postérieur ou un dans chacun ; les ébauches des 2 glandes cémentaires tubulaires sont évidentes ; de solides faisceaux de fibres relient le tronc antérieur et postérieur ; le tronc postérieur a une cuticule à surface ondulée. Les séquences d'analyse moléculaire (COI et 18S) coïncidaient avec la morphologie et confirmaient sa taxonomie. Le profil phylogénétique a révélé que P. rancoensis n. sp. appartient au clade Profilicollis. Les deux séquences ont montré une faible variation génétique et trois haplotypes différents ont été trouvés. La nouvelle espèce était plus proche de P. botulus (Van Cleave, 1916) Witenberg, 1932 que des autres espèces de Profilicollis.