Molecular and morphological studies on Contracaecum rudolphii A and C. rudolphii B in great cormorants (Phalacrocorax carbo sinensis) from Italy and Israel.

The distribution of parasites is shaped by a variety of factors, among which are the migratory movements of their hosts. Israel has a unique position to migratory routes of several bird species leaving Europe to winter in Africa, however, detailed studies on the parasite fauna of birds from this area are scarce. Our study investigates occurrence and distribution of sibling species among Contracaecum rudolphii complex in Phalacrocorax carbo sinensis from Italy and Israel, to acquire further information on the geographical range of these species to gain deeper knowledge on the ecology of these parasites and their bird host. A total of 2383 Contracaecum were collected from the gastric mucosa of 28 great cormorants (18 from Israel and 10 from Italy). A subsample was processed for morphological analyses in light and scanning electron microscopy (SEM), and for molecular analyses through amplification and sequencing of the ITS rDNA and the cox2 mtDNA, and through PCR-RFLP. All the 683 Contracaecum subjected to molecular identification belonged to C. rudolphii s.l., (300 C. rudolphii A and 383 C. rudolphii B). SEM micrographs provided, for the first time, details of taxonomic structures in male specimens from both sibling species, and the first SEM characterization of C. rudolphii B. This work presents the first data on the occurrence of sibling species of C. rudolphii in Israel and provides additional information on the distribution of C. rudolphii A and B in Italy, confirming the high prevalence and intensity of infection observed in Ph. carbo sinensis from other Italian areas.

An update and ecological perspective on certain sentinel helminth endoparasites within the Mediterranean Sea.

The Mediterranean Sea is recognized as a marine biodiversity hotspot. This enclosed basin is facing several anthropogenic-driven threats, such as seawater warming, pollution, overfishing, bycatch, intense maritime transport and invasion by alien species. The present review focuses on the diversity and ecology of specific marine trophically transmitted helminth endoparasites (TTHs) of the Mediterranean ecosystems, aiming to elucidate their potential effectiveness as 'sentinels' of anthropogenic disturbances in the marine environment. The chosen TTHs comprise cestodes and nematodes sharing complex life cycles, involving organisms from coastal and marine mid/upper-trophic levels as definitive hosts. Anthropogenic disturbances directly impacting the free-living stages of the parasites and their host population demographies can significantly alter the distribution, infection levels and intraspecific genetic variability of these TTHs. Estimating these parameters in TTHs can provide valuable information to assess the stability of marine trophic food webs. Changes in the distribution of particular TTHs species can also serve as indicators of sea temperature variations in the Mediterranean Sea, as well as the bioaccumulation of pollutants. The contribution of the chosen TTHs to monitor anthropogenic-driven changes in the Mediterranean Sea, using their measurable attributes at both spatial and temporal scales, is proposed.

Detection of Lotmaria passim in honeybees from Emilia Romagna (Italy) based on a culture method.

Lotmaria passim is considered an emerging field of study in honeybee pathology, since it can threaten the health of the colony leading to a higher mortality rate. However, there is a lack of knowledge regarding the diffusion of this trypanosomatid in Italy. In this study, we highlight the presence of L. passim in the province of Bologna through its culture isolation from honeybee guts and microscopic observation.

Molecular characterization of Dictyocaulus nematodes in wild red deer Cervus elaphus in two areas of the Italian Alps.

Nematodes of the genus Dictyocaulus are the causative agents of parasitic bronchitis and pneumonia in several domestic and wild ungulates. Various species have been described in wild cervids, as the case of Dictyocaulus cervi in red deer, recently described as a separate species from Dictyocaulus eckerti. In Italy, information on dictyocaulosis in wildlife is limited and often outdated. In this work, 250 red deer were examined for the presence of Dictyocaulus spp. in two areas of the Italian Alps (n = 104 from Valle d'Aosta, n = 146 from Stelvio National Park), and the retrieved lungworms were molecularly characterized. Lungworms were identified in 23 and 32 animals from Valle d'Aosta and Stelvio National Park, respectively. The nematodes, morphologically identified as D. cervi, were characterized molecularly (18S rDNA, ITS2, and coxI). Consistently, almost all specimens were found to be phylogenetically related to D. cervi. Three individuals, detected from both study sites and assigned to an undescribed Dictyocaulus sp., clustered with Dictyocaulus specimens isolated from red deer and fallow deer in previous studies. Within each of D. cervi and the undescribed Dictyocaulus sp., the newly isolated nematodes phylogenetically clustered based on their geographical origin. This study revealed the presence of D. cervi in Italian red deer, and an undetermined Dictyocaulus sp. that should be more deeply investigated. The results suggest that further analyses should be focused on population genetics of cervids and their lungworms to assess how they evolved, or co-evolved, throughout time and space and to assess the potential of transmission towards farmed animals.

Advancing understanding of the taxonomy and diversity of the genus Contracaecum in the great white pelican (Pelecanus onocrotalus).

Despite the wide distribution and health importance of anisakids of the genus Contracaecum, epidemiological data on their occurrence in definitive bird hosts are scarce, particularly from certain parts of the world that represent important wintering sites or migration stopovers for different bird species. In the present study, Contracaecum spp. infecting six great white pelicans (Pelecanus onocrotalus) in Israel were identified using light and scanning electron microscopy and phylogenetic analyses of nuclear internal transcribed spacer (ITS) and mitochondrial cytochrome c oxidase II (cox2). A PCR-RFLP method was also developed and applied to screen large numbers of Contracaecum parasites. Most (415/455) worms recovered were C. micropapillatum, followed by C. gibsoni (31/455), C. quadripapillatum (8/455), and C. multipapillatum E (1/455). Contracaecum micropapillatum from Israel and C. bancrofti from Australia are distinguishable by cox2 but less well resolved with ITS sequences, and could not be distinguished morphologically. Worms with cox2 matching C. gibsoni had ITS matching specimens identified as C. multipapillatum A. To the authors' knowledge, this represents the first of such studies in Israel and provides useful data on the ecology and distribution of different Contracaecum species of health and economic interest.

Anisakid and Raphidascaridid parasites in Trachurus trachurus: infection drivers and possible effects on the host's condition.

This study investigated the distribution of nematode larvae of Anisakidae and Raphidascarididae (genera Anisakis and Hysterothylacium) in Trachurus trachurus (Linnaeus, 1758) in the Ligurian and central-northern Tyrrhenian Seas. The relationship between the number of parasites and the length and weight parameters of the fish was assessed, and the possible effect of the parasites on the condition factor was evaluated. A total of 190 T. trachurus specimens were collected in July 2019. Parasites were found in 70 individuals. A total of 161 visible larvae were collected in the viscera. Morphological analysis revealed the presence of Anisakis spp. in 55 fish and Hysterothylacium spp. in 15 fish, while 5 fish showed coinfection with both genera. The specimens subjected to PCR (n = 67) showed that 85% of the Anisakis larvae analyzed belonged to the species A. pegreffii, while the remaining 15% belonged to hybrids of A. pegreffii-A. simplex (s.s.). A total of 58% (n = 7) of the Hysterothylacium larvae analyzed belonged to the species H. fabri, while 42% belonged to the species H. aduncum. Our results support the hypothesis that infection with these parasites does not affect the condition of the fish host analyzed, and that body size and depth are major drivers in determining infection levels with Anisakid and Raphidascaridid nematodes.

A new species of Clinostomum Leidy, 1856 based on molecular and morphological analysis of metacercariae from African siluriform fishes.

In the Afrotropic region, the genus Clinostomum is represented by four accepted and four unnamed species distinguished using molecular data. Here, we describe one of the four unnamed species as Clinostomum ukolii n. sp. based on metacercariae from siluriform fishes (Synodontis batensoda, Schilbe intermedius) collected in Nigeria and South Africa. The new species is distinguished by molecular data (39 new sequences of partial cytochrome c oxidase I ≥ 6.7% divergent from those of other species) and morphological differences from named and unnamed species in the same region. Metacercariae of C. ukolii n. sp. can be distinguished based on size, tegumental spines, and various aspects of the genital complex, including its position, lobation of the anterior testis, and the disposition and shape of the cirrus pouch. Although descriptions of new species of digeneans are typically based on the morphology of adults, we argue that in cases where data are available from metacercariae from regionally known species, new species can be described based on metacercariae, particularly when supported by molecular data, as here. Moreover, sub-adult reproductive structures can be clearly visualized in metacercaria of Clinostomum. Considering metacercariae as potential types for new species could advance clinostome systematics more rapidly, because metacercariae are encountered much more often than adults in avian definitive hosts.

Molecular data show Clinostomoides Dollfus, 1950 is a junior synonym of Clinostomum Leidy, 1856, with redescription of metacercariae of Clinostomum brieni n. comb.

The genus Clinostomoides Dollfus, 1950 was erected to accommodate a single worm from Ardea goliath sampled in the Belgian Congo. The specimen was distinguished from other clinostomids by its large size and posterior genitalia. In the following years, metacercariae of Clinostomoides brieni, have been described in Clarias spp. in southern and western Africa. A few authors have referred to Clinostomum brieni, but all such usages appear to be lapsus calami, and the validity of Clinostomoides remains widely accepted. In this study our aim was: position C. brieni among the growing clinostomids molecular database, and redescribe the species with emphasis on characters that have emerged as important in recent work. We sequenced two nuclear (partial 18S and ITS) and one mitochondrial marker (partial cytochrome c oxidase I) and studied morphology in metacercariae from hosts and localities likely to harbour the type species (Clarias spp., Democratic Republic of the Congo, South Africa). Phylogenetic analysis shows C. brieni belongs within Clinostomum Leidy, 1856. We therefore transfer C. brieni to Clinostomum, amend the diagnosis for the genus Clinostomum and provide a critical analysis of other species in Clinostomoides, all of which we consider species inquirendae, as they rest on comparisons of different developmental stages.

Haplosporidium pinnae associated with mass mortality in endangered Pinna nobilis (Linnaeus 1758) fan mussels.

The fan mussel, Pinna nobilis (Linnaeus 1758), is an endemic bivalve of the Mediterranean basin, protected by international legislation as an endangered species. In the early summer of 2018, a mass mortality event (MME) of P. nobilis was recorded in the Gulf of Taranto (Southern Italy, Ionian Sea). Moribund specimens of P. nobilis were collected by scuba divers and processed by bacteriological, parasitological, histopathological and molecular analyses to investigate the causes of this MME. Different developmental stages (i.e., plasmodia, spores and sporocysts) of a presumptive haplosporidian parasite were observed during the histological analysis in the epithelium and in the lumen of the digestive tubules, where mature spores occurred either free or in sporocysts. The spores presented an operculum and an ovoid shape measuring 4.4 µm (±0.232) in length and 3.6 µm (±0.233) in width. BLAST analysis of an 18SrRNA sequence revealed a high nucleotide similarity (99%) with the reference sequence of Haplosporidium pinnae available in GenBank database. Phylogenetic analysis clustered the sequence of the pathogen in a paraphyletic clade with the reference sequence of H. pinnae, excluding other haplosporidians (i.e., Bonamia and Minchinia genera). Based on data reported, H. pinnae was the causative agent of MME in the populations of P. nobilis sampled in the Ionian Sea, where the conservation of this endangered species is heavily threatened by such a protozoan infection. Further investigations should contribute to knowledge about the life cycle of H. pinnae in order to reduce spread of the pathogen and to mitigate the burden of the disease where P. nobilis is facing the risk of extinction.

In vitro activity of chemicals and commercial products against Saprolegnia parasitica and Saprolegnia delica strains.

Oomycetes of the genus Saprolegnia are responsible for severe economic losses in freshwater aquaculture. Following the ban of malachite green in food fish production, the demand for new treatments pushes towards the selection of more safe and environment-friendly products. In the present work, in vitro activity of ten chemicals and three commercial products was tested on different strains of Saprolegnia, using malachite green as reference compound. The compounds were screened in agar and in water to assess the minimum inhibitory concentration (MIC) and the minimum lethal concentration (MLC), respectively. Two strains of Saprolegnia parasitica and one isolate of Saprolegnia delica were tested in triplicate per each concentration. Among tested chemicals, benzoic acid showed the lowest MIC (100 ppm) followed by acetic acid, iodoacetic acid and copper sulphate (250 ppm). Sodium percarbonate was not effective at any tested concentration. Among commercial products, Virkon™ S was effective in inhibiting the growth of the mycelium (MIC = MLC = 1,000 ppm). Actidrox® and Detarox® AP showed MIC = 5,000 and 1,000 ppm, respectively, while MLCs were 10-fold lower than MICs, possibly due to a higher activity of these products in water. Similarly, a higher effectiveness in water was observed also for iodoacetic acid.

A new species of Clinostomum Leidy, 1856 in East Asia based on genomic and morphological data.

Metacercariae of Clinostomum Leidy, 1856 are frequently encountered in freshwater fish. In 2015, a provisional species of Clinostomum in People's Republic of China (PRC) was distinguished from C. complanatum (Rudolphi, 1819) in Europe based on divergent cytochrome c oxidase I (CO1). However, in subsequent studies in East Asia, the same divergent CO1 genotype was identified as C. complanatum. These matching sequences suggest that either the provisional East Asian species was incorrectly distinguished from C. complanatum in 2015 or that C. complanatum in East Asia was misidentified in later studies. We tested these alternatives by sequencing the mitochondrial genome of C. complanatum in Italy, which was 5.7% divergent from a previously published sequence from Clinostomum in PRC, including differences in 80 of 3390 (2.4%) translated amino acids. Partial CO1 sequences of specimens from PRC and those from Italy, Romania, and Turkey also each formed reciprocally monophyletic clades. Partial CO1 from the East Asian clade varied by mean 3.6% (range 2.4-4.8%) from C. complanatum from Italy, Romania, and Turkey; mean intra-clade CO1 variation was 0.3% (range 0-1.9%). Metacercariae from Europe and East Asia display significant morphometric variation, and data from the literature suggest morphological differences in the genital complex of adults. Although sequences of nuclear rDNA did not differ between isolates from the west and East Asia, taken together, these results lead us to describe a new species of Clinostomum.

Redescription of Philometra globiceps (Rudolphi, 1819) (Nematoda: Philometridae), the type species of Philometra Costa, 1845, including the first data obtained by SEM.

A redescription of Philometra globiceps (Rudolphi 1819), the type species of Philometra Costa 1845 (Philometridae), is provided on the basis of specimens collected from the gonads, stomach, pyloric caeca, intestine and gallbladder of the marine fish Uranoscopus scaber Linnaeus (Uranoscopidae, Perciformes) caught in the Ionian Sea off Ugento, southern Italy. Light microscopical and scanning electron microscopical examinations (latter used for the first time in this species) of the specimens revealed some previously unreported morphological features, such as the location of submedian pairs of cephalic papillae of external circle on four elevated cuticular lobes in gravid females, the presence of amphids, genital papillae and phasmids in males, the lamellate structure of the distal end of gubernaculum appearing as a dorsal protuberance in lateral view and the structure of the male caudal end. A taxonomically important feature of P. globiceps is the details in the dorsal transverse lamella-like structures on the distal end of the gubernaculum, by which this species can be separated from other gonad-infecting species of this genus. Apparently, P. globiceps is a specific parasite of U. scaber and all previous records of this species from hosts belonging to other fish families are evidently based on misidentifications.

Morphological and molecular data on acuariid nematodes in European great cormorants (Phalacrocorax carbo sinensis) and pygmy cormorants (Microcarbo pygmaeus).

The family Acuariidae is a speciose group of parasitic nematodes, infecting mostly birds as definitive hosts. This study focused on the characterization of two species of acuariids, collected in two different species of piscivorous birds, the European great cormorant Phalacrocorax carbo sinensis from Italy, and the pygmy cormorant Microcarbo pygmaeus from Israel. Parasites were analyzed using light and scanning electron microscopy and by amplification and sequencing of the 28S rDNA. The results of morphological and molecular analyses showed that Ph. carbo sinensis was infected by the acuariid Syncuaria squamata (12 females) and Cosmocephalus obvelatus (1 female), whereas M. pygmaeus was infected by C. obvelatus (2 males, 12 females). The present results provide new data on the distribution of acuariid parasites of piscivorous birds, the first report of Acuariidae in Israel, and the first molecular data on S. squamata and C. obvelatus, which will be useful in future epidemiological and phylogenetic studies of these widely distributed, but less molecularly studied parasites.

Viral Encephalopathy and Retinopathy in groupers (Epinephelus spp.) in southern Italy: a threat for wild endangered species?

BACKGROUND: Betanodaviruses are the causative agents of Viral Encephalopathy and Retinopathy (VER). To date, more than 50 species have proved to be susceptible and among them, those found in genus Epinephelus are highly represented. Clinical disease outbreaks are generally characterized by typical nervous signs and significant mortalities mainly associated with aquaculture activities, although some concerns for the impact of this infection in wild fish have been raised. In this study, the authors present the first documented report describing an outbreak of VER in wild species in the Mediterranean basin. CASE PRESENTATION: In late summer--early winter 2011 (September-December), significant mortalities affecting wild Dusky grouper (Epinephelus marginatus), Golden grouper (Epinephelus costae) and European sea bass (Dicentrarchus labrax) were reported in the municipality of Santa Maria di Leuca (Northern Ionian Sea, Italy). The affected fish showed an abnormal swimming behavior and swollen abdomens. During this epizootic, five moribund fish showing clear neurological signs were captured and underwent laboratory investigations. Analytical results confirmed the diagnosis of VER in all the specimens. Genetic characterization classified all betanodavirus isolates as belonging to the RGNNV genotype, revealing a close genetic relationship with viral sequences obtained from diseased farmed fish reared in the same area in previous years. CONCLUSION: The close relationship of the viral sequences between the isolates collected in wild affected fish and those isolated during clinical disease outbreaks in farmed fish in the same area in previous years suggests a persistent circulation of betanodaviruses and transmission between wild and farmed stocks. Further investigations are necessary to assess the risk of viral transmission between wild and farmed fish populations, particularly in marine protected areas where endangered species are present.

Parasitic infection in the scyphozoan Rhizostoma pulmo (Macri, 1778).

Very little information is reported for parasites of cnidarians, therefore, the present work aimed to investigate parasitic infections in one of the most widespread jellyfish in the Mediterranean Sea, Rhizostoma pulmo. The goals were to determine prevalence and intensity of parasites in R. pulmo, identify the species involved through morphological and molecular analysis, test whether infection parameters differ in different body parts and in relation to jellyfish size. 58 individuals were collected, 100% of them infected with digenean metacercariae. Intensity varied between 18.7 ± 6.7 per individual in 0-2 cm diameter jellyfish up to 505 ± 50.6 in 14 cm ones. Morphological and molecular analyses suggest that the metacercariae belonged to the family Lepocreadiidae and could be possibly assigned to the genus Clavogalea. Prevalence values of 100% suggest that R. pulmo is an important intermediate host in the life cycle of lepocreadiids in the region. Our findings also support the hypothesis that R. pulmo is an important part in the diet of teleost fish, which are reported as definitive hosts of lepocreadiids, since trophic transmission is necessary for these parasites to complete their life cycles. Parasitological data may therefore be useful to investigate fish-jellyfish predation, integrating traditional methods such as gut contents analysis.

Unveiling a novel parasitosis: Trichostrongylus colubriformis infection in captive ring-tailed lemurs (Lemur catta).

Ring-tailed Lemur (Lemur catta) is the only surviving semi-terrestrial diurnal lemur in Madagascar. Despite being the most intensively studied of lemur taxa, only a few helminths have been described in this species. In this study we describe a persistent infection due to Trichostrongylus colubriformis in a captive population of L. catta hosted in a zoological park of northern Italy. In the context of a parasitological survey on zoo animals, we investigated parasites in a captive colony of ring-tailed lemurs within a zoological park. Parasitological analysis included necropsy of a deceased lemur in 2019, subsequent fecal sample collections in 2021-2022, followed by coprological examination and coprocolture. Morphological and molecular analyses were conducted on adult helminths, larvae and eggs, involving microscopy, scanning electron microscopy (SEM), and sequencing of the ITS rDNA region. Trichostrongylidae parasites were primarily found after necropsy in the intestine of the lemur. Morphological and molecular investigations on adults and eggs/larvae recovered from feces collected at different times from lemurs of the same captive population, allowed to properly identify the parasite as T. colubriformis. To the best of our knowledge this is the first description of T. colubriformis in L. catta. Although its presence in wild populations is not necessarily implied by our finding, this parasitosis represent a cause of concern in captive lemurs, considering the possibility of interspecies transmission and the zoonotic implications.

On the conservation of white-clawed crayfish in the Iberian Peninsula: Unraveling its genetic diversity and structure, and origin.

European crayfish species are a clear example of the drastic decline that freshwater species are experiencing. In particular, the native species of the Iberian Peninsula, the white clawed-crayfish (WCC) Austropotamobius pallipes, is listed as "endangered" by the IUCN and included in Annex II of the EU Habitat Directive and requires especially attention. Currently, implemented conservation management strategies require a better understanding of the genetic diversity and phylogeographic patterns, as well as of its evolutionary history. For this purpose, we have generated the largest datasets of two informative ribosomal mitochondrial DNA regions, i.e., cytochrome oxidase subunit I and 16S, from selected populations of the WCC covering its geographical distribution. These datasets allowed us to analyze in detail the (i) genetic diversity and structure of WCC populations, and (ii) divergence times for Iberian populations by testing three evolutionary scenarios with different mtDNA substitution rates (low, intermediate, and high rates). The results indicate high levels of haplotype diversity and a complex geographical structure for WCC in the Iberian Peninsula. The diversity found includes new unique haplotypes from the Iberian Peninsula and reveals that most of the WCC genetic variability is concentrated in the northern and central-eastern regions. Despite the fact that molecular dating analyses provided divergence times that were not statistically supported, the proposed scenarios were congruent with previous studies, which related the origin of these populations with paleogeographic events during the Pleistocene, which suggests an Iberian origin for these WCC. All results generated in this study, indicate that the alternative hypothesis of an introduced origin of the Iberian WCC is highly improbable. The result of this study, therefore, has allowed us to better understand of the genetic diversity, structure patterns, and evolutionary history of the WCC in the Iberian Peninsula, which is crucial for the management and conservation needs of this endangered species.

Low prevalence of Contracaecum third-stage larvae parasitizing Sea of Galilee fisheries: 1-year survey after 57 years of no information.

Freshwater and marine ecosystems are a suitable habitat for parasitic nematodes of the genus Contracaecum (family: Anisakidae) to complete their complex life cycle. Several fish species of the Sea of Galilee (Lake Kinneret) were reported in 1964 as second intermediate/paratenic hosts of Contracaecum spp. larvae. The lack of taxonomically relevant morphological features of these larvae hindered their proper identification. Here we report the results of a 1-year survey conducted in 2021, 57 years after the first (and only) such survey. We analyzed 352 specimens from 10 fish species (native and non-native) of the Sea of Galilee (Israel) ichthyofauna. We compared our results with those of the first parasitological survey conducted by Paperna in 1964; the overall prevalence of nematodes referable to Contracaecum larvae was 16.8% and 0.85% in 1964 and in 2021, respectively. Different from the first survey that identified Contracaecum larvae morphologically, we used both morphological and molecular tools. Two wild native cyprinids-Jordan himri (Carasobarbus canis) and Jordan barbel (Luciobarbus longiceps)-were infected (a single specimen each) with Contracaecum quadripapillatum larvae in their abdominal cavity. A single specimen of blue tilapia (Oreochromis aureus) was infected with two larvae of Contracaecum multipapillatum E, localized in the pericardial cavity. The findings of our study, which is part of a large project focused on Contracaecum spp. infecting both piscivorous birds and fish collected in Israel, advance our knowledge about the distribution and host range of this potentially zoonotic parasite in fishery products of the Sea of Galilee.

Morphological description and molecular characterization of Contracaecum larvae (Nematoda: Anisakidae) parasitizing market-size hybrid tilapia (Oreochromis aureus x Oreochromis niloticus) and red drum (Sciaenops ocellatus) farmed in Israel.

Nematodes belonging to the genus Contracaecum (family: Anisakidae) are heteroxenous parasites with a complex life cycle. Contracaecum larvae infecting farmed fish and fishery products are economically important causing market rejection in massive infection and may have zoonotic potential. In Israel, Contracaecum larvae have been described morphologically in several fish species; however, none of these descriptions were supported by molecular tools. In 2019-2020, hybrid tilapia (Oreochromis aureus x Oreochromis niloticus) and red drum (Sciaenops ocellatus), farmed in polyculture were found to be heavily infected with nematodes referable to Contracaecum larvae. Prevalence of infection in hybrid tilapia and red drum was 53.8% and 40.9%, respectively. A combined (morphological and molecular) approach revealed that both infected fish species were parasitized by the same species of Contracaecum, although larvae in hybrid tilapia were localized in the pericardial cavity whereas in red drum, they were observed in the abdominal cavity. Genetic analysis of internal transcribed spacer rDNA and cox2 mtDNA showed high similarity to unidentified Contracaecum larvae detected in several fish species in Ethiopia, Egypt and Kenya. In this study, molecular and morphological analyses place the possible new species in the C. multipapillatum complex and was provisionally named C. multipapillatum E. Further analyses combining morphological and molecular approaches are required on adult specimens collected from piscivorous birds living in the same area to support the identification of a potentially new species.