A new species of Loimopapillosum Hargis, 1955 (Monogenea: Monocotylidae) parasitizing Hypanus dipterurus (Myliobatiformes: Dasyatidae) off the Pacific coast of South America, and its phylogenetic relationships

Abstract

A new species of Loimopapillosum Hargis, 1955 is described based on specimens collected from the gills of the diamond stingray, Hypanus dipterurus (Jordan & Gilbert, 1880) (Myliobatiformes: Dasyatidae) captured off Puerto Pizarro, Tumbes Region, northern Peru. Loimopapillosum pascuali n. sp. is distinguished mainly from the type and only species, Loimopapillosum dasyatis Hargis, 1955, by its funnel-shaped male copulatory organ, with an asymmetrical base; the superficial root of the anchor with distal knobs; the deep root of the anchor with a constriction at its base; a single testis; and the number of head organs. Available sequences for members of Monocotylidae in the GenBank as well as partial sequences for the gene 28S and 18S ribosomal DNA from L. pascuali n. sp. were included in phylogenetic analyses, suggesting that Loimoinae (represented in this study by L. pascuali n. sp. and Loimosina sp.) is nested within the Monocotylidae Taschenberg, 1879. Therefore, we confirm the rejection of Loimoidae Price, 1936 and its reincorporation as a subfamily of Monocotylidae, as previously suggested. Loimopapillosum pascuali n. sp. represents the first species of this genus in South America.

Hexabothriidae and Monocotylidae (Monogenoidea) from the gills of neonate hammerhead sharks (Sphyrnidae) Sphyrna gilberti, Sphyrna lewini and their hybrids from the western North Atlantic Ocean

“…This corroborates the decision that the species of these genera are allocated within the Monocotylidae and do not compose a monophyletic assemblage within the family, following the suggestion of Boeger et al (2014) and Chero et al (2021). Although there is no sequence currently available for the species of Loimos, molecular phylogenetic analyses using sequences of Loimosina from the present study and from Boeger et al (2014), and Loimopapillosum (see Chero et al, 2021), strongly indicate that these are members of distinct clades within the Monocotylidae. The classification of Loimos and a more robust decision on the validity of Loimoidae/Loimoinae, however, should await sequencing of corresponding DNA fragments and phylogenetic analysis.…”

“…Although there is no sequence currently available for the species of Loimos , molecular phylogenetic analyses using sequences of Loimosina from the present study and from Boeger et al . (2014), and Loimopapillosum (see Chero et al ., 2021), strongly indicate that these are members of distinct clades within the Monocotylidae. The classification of Loimos and a more robust decision on the validity of Loimoidae/Loimoinae, however, should await sequencing of corresponding DNA fragments and phylogenetic analysis.…”

“…(2014) and Chero et al . (2021). Although there is no sequence currently available for the species of Loimos , molecular phylogenetic analyses using sequences of Loimosina from the present study and from Boeger et al .…”

An Annotated Checklist of Monogeneans (Platyhelminthes, Monogenea) from Aquatic Vertebrates in Peru: A Review of Diversity, Hosts and Geographical Distribution

“…Hypanus dipterurus ; gills; marine; Tumbes (3°29′ S, 80°24′ W) (holotype, MUSM-HEL 4660; paratypes, MUSM-HEL 4661a-x) [ 141 ].…”

“…The taxonomic exploration of monogeneans in Peru has primarily relied on morphological data [ 41 , 43 , 49 , 52 , 53 , 63 , 64 , 85 , 106 , 111 , 112 , 113 , 116 , 121 , 125 , 137 , 138 ] with limited integration of molecular methodologies to elucidate phylogenetic relationships among species [ 34 , 36 , 54 , 57 , 61 , 62 , 107 , 141 , 146 , 149 ]. As of the present date, molecular characterization has been performed on 51 monogenean species, including 48 species within the Dactylogyridae [ 34 , 36 , 54 , 57 , 61 , 62 , 107 ], 2 within the Hexabothriidae [ 146 , 149 ], and 1 within the Monocotylidae [ 141 ]. Dactylogyrids infecting siluriform fish have been the most extensively studied species using molecular approaches to comprehend their phylogenetic interrelations [ 34 , 36 , 54 , 57 , 61 , 62 , 107 ].…”