Browsing by Author "Cruz-Neyra, Lidia"

Now showing 1 - 4 of 4

Complete mitochondrial genome assembly and analysis of a Neotropical lineage of Ligula intestinalis reveals evolutionary and phylogenetic insights
(Springer Science and Business Media LLC, 2026-02-17) Mondragón-Martínez, Aarón; Martínez-Rojas, Rosa; Gárate, Inés; Sánchez-Venegas, Jaime R; Moreno-Morales, Gerald; Cruz-Neyra, Lidia; Cruces, Celso Luis; Garcia-Candela, Enrique; Escudero, Frank Guzman; Chero, Jhon D; Yunis-Aguinaga, Jefferson; Štefka, Jan; Nazarizadeh, Masoud
Ligula intestinalis (Cestoda: Diphyllobothriidea) is a cosmopolitan tapeworm parasite characterized by a complex life cycle that includes freshwater fish infection. Ligula disrupts host reproduction, and causes ecological imbalances. Despite its broad geographic distribution and ecological significance, molecular data for South American populations have been lacking, leaving a critical gap in understanding its genetic diversity and evolutionary history. To address this, we conducted the first molecular characterization of L. intestinalis plerocercoid larvae isolated from the native fish Orestias agassizii in Lake Titicaca, Peru. Using Illumina next-generation sequencing, we assembled a complete mitochondrial genome of 13,657 bp, containing 12 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions. The mitogenome exhibited an A + T-rich composition (66.3%) and contained over 580 repetitive elements, primarily concentrated within its control region. Comparative analyses with European and Asian mitogenomes revealed substantial regional differences in nucleotide diversity and amino acid composition, with closer similarity observed between South American and Asian lineages. Genes atp6, nad5, and nad6 showed the highest variability, whereas cox1 demonstrated significant intercontinental divergence yet remained conserved within South America, reflecting both phylogeographic patterns and strong functional constraints. Phylogenetic inference based on mitochondrial markers (cytb, cox1, and nd1) confirmed the Titicaca specimen as a distinct South American lineage, closely related to the Nearctic lineage. These findings enhance our understanding of L. intestinalis mitogenomic diversity, emphasize the importance of geographic isolation in parasite diversification, and provide an essential genomic resource for future evolutionary and ecological research in high-altitude ecosystems.
Molecular and morphological identification of Adenocephalus pacificus (Cestoda) isolated from South American sea lion Otaria byronia stranded on the northern Peruvian coasts
(Polish Parasitological Society, 2021) Mondragón-Martiínez, Aarón; Martínez-Rojas, Rosa; Cruz-Neyra, Lidia; De-Los-Santos, Estrellita Rojas; Delgado-Candela, Abraham
The most frequent etiologic agent of diphyllobothriosis in South America and the only one confirmed by molecular data in human cases in Peru is Adenocephalus pacificus (syn. Diphyllobothrium pacificum). This cestode is transmitted by ingestion of the plerocercoids found in marine fish, causing a parasitic zoonosis. The objective of the present study was to identify two cestodes isolated from two specimens of the South American sea lion (Otaria byronia) stranded on the beaches of Huacho and Barranca cities, located on the northern Peruvian coasts, in the department of Lima. Tapeworms were confirmed by morphological characteristics due to the presence of transverse papilla-like tegumental protuberances in proglottids and small sized eggs, as well as by sequencing of the partial cytochrome c oxidase subunit 1 (mtDNA-COI) gene that are congruent with additional available A. pacificus sequences. Even though sea lions in Peru are distributed along the coast and in areas of difficult access, generally located in protected natural areas, the fortuitous finding represented an opportunity to confirm the presence of A. pacificus in South American sea lions. This report of tapeworm A. pacificus could allow future monitoring of the occurrence and geographical distribution of this causative agent in epidemiological studies, since it is one of the main species of zoonotic importance in Peru. © 2024 Elsevier B.V., All rights reserved.
Molecular identification and epidemiological data of Anisakis spp. (Nematoda: Anisakidae) larvae from Southeastern Pacific Ocean off Peru
(Elsevier BV, 2021-12) Martínez-Rojas, Rosa; Mondragón-Martínez, Aarón; De-Los-Santos, Estrellita Rojas; Cruz-Neyra, Lidia; García-Candela, Enrique; Delgado-Escalante, Abraham; Sanchez-Venegas, J.R.
The objective of this study is to determine the infection status of nematode larvae and record epidemiological molecular data in commercial fish from the southeast Pacific off the central coast of Peru. Anisakiasis is a fish-borne zoonosis caused by Anisakis larvae, parasites of relevance in the fishery resources that have negative impact on public health. Between January 2012 to December 2014, 345 specimens of four fish species (Trachurus symmetricus murphyi, Scomber japonicus peruanus, Merluccius gayi peruanus and Seriolella violacea) were examined for Anisakis sp. larvae. A total of 997 Anisakis sp. larvae were found in the body cavity of 196 fish (total prevalence 53.7%, total mean intensity 5.08). After morphological analysis, 958 (96.08%) larvae were identified as Type I and 39 (3.92%) as Type II. Specimens were identified by molecular analysis of the mitochondrial cytochrome c oxidase subunit II (cox2) gene, confirming that A. pegreffii is the predominant species and the most important agent of human anisakiasis off the Peru Central Coast. In addition, we revealed the occurrence of A. physeteris (s.l.) in S. japonicus peruanus (P = 18.0%; MI = 2.17). Therefore, the results obtained in the present study improve the knowledge of the occurrence of Anisakis species in the commercial fish from the Southeastern Pacific Ocean, highlighting the importance of considering a potential hazard for humans and the necessity of further research in other fishes of greater preference by the Peruvian population. © 2021 Elsevier B.V., All rights reserved.
Molecular identification of Mymarothecium viatorum and Anacanthorus penilabiatus in extensive native fish farming systems of the Peruvian Amazon
(Elsevier BV, 2024-9) Cabrera-Soregui, Milagros; Torres-Lozano, Karel; Garcia-Candela, Enrique; Mesias-Valle, Fernando; Martinez-Rojas, Rosa; Cruz-Neyra, Lidia; Mondragón-Martínez, Aarón; Ebert, Mariana Bertholdi; Da Silva, Reinaldo José; Cala-Delgado, Daniel Leonardo
Piaractus brachypomus (Pacú) is the main native fish species cultivated in Peru and holds great potential for growth in aquaculture from the Peruvian Amazon. Between October 2021 and January 2022 in two fish producing farms in the Amazon region of San Martín in Peru, P. brachypomus individuals were examined for parasite evaluation. A total of 6366 monogeneans were isolated from the gills of 30 fish, revealing a prevalence of 100%, with an abundance and mean intensity of 212 parasites per fish. Monogeneans were morphologically identified as Mymarothecium viatorum and Anacanthorus penilabiatus. The genetic divergence in the 28S rDNA gene found among A. penilabiatus sequences was 0.1% and among Anacanthorus spp. it ranged from 0.9% to 7.5%. The genetic divergence found among the M. viatorum sequences was 0.3%. These finding represents the first molecular data of M. viatorum and A. penilabiatus in Peru using the 28S rDNA gene of these monogeneans. The new sequences obtained will contribute to future studies on the phylogenetic relationships among dactylogyrids. However, further research with a broader range of host-parasite samples and additional genetic markers is needed to clarify these relationships and provide stronger support for the phylogenetic positions. © 2024 Elsevier B.V., All rights reserved.