New species of Cacatuocotyle (Monogenoidea, Dactylogyridae) parasitizing the anus and the gill lamellae of Astyanax aeneus (Pisces, Ostariophysi: Characidae) from the Rio Lacantún basin in the Biosphere Reserve of Montes Azules, Chiapas, Mexico

Abstract

As part of a biological inventory of the Rio Lacantún basin in the Biosphere Reserve of Montes Azules from Chiapas State (southeastern, Mexico), the following monogenoid ectoparasites infecting the external surface of the anal opening and the gill lamellae of the freshwater fish Astyanax aeneus (Characidae) in ten streams were found: Cacatuocotyle chajuli sp. nov. (anus), Cacatuocotyle exiguum sp. nov., and Cacatuocotyle sp. (gill lamellae). C. chajuli is differentiated from its single congener, Cacatuocotyle paranaensis (Boeger et al. Syst Parasitol 36:75-78, 1997), from the gills of Characidium lanei (Characidae) from Paraná Brazil, in having a noticeably V-shaped haptoral bar and larger hooks and anchors. C. exiguum differs from these two latter species in the size of its anchors. Illustrations and data on morphological and biometric variability of individual specimens of C. chajuli and C. exiguum from different streams are provided. The present data support the statement about three species of Astyanax, which harbor the richest monogenoidean diversity in the Neotropics with a total of 18 species reported up to now. Occurrences of species of Cacatuocotyle on different sites of infection on three distant host species [including a Neotropical cichlid (Cichlidae) species] suggest that these monogenoideans switching to new hosts can result in the availability of potential hosts within the same habitat instead of showing signs of preferential switching between closely related hosts or on their respective microhabitats.

Morphological and molecular (28S rRNA) data of monogeneans (Platyhelminthes) infecting the gill lamellae of marine fishes in the Campeche Bank, southwest Gulf of Mexico

“…Parasites were subsequently detached from the gills using fine needles under a dissecting microscope, stained with Gomori’s trichrome stain and mounted in Canada balsam ( Vidal-Martínez et al 2001 ). A selection of specimens was mounted on slides using a mixture of lactic acid ( LA ) and glycerin-ammonium picrate ( GAP ) and then remounted in Canada balsam ( Mendoza-Franco et al 2013 ) to obtain measurements of the haptoral structures and copulatory complex.…”

Ecto- and endo-parasitic monogeneans (Platyhelminthes) on cultured freshwater exotic fish species in the state of Morelos, South-Central Mexico

“…Subsequently, all monogeneans specimens were isolated and stained with Gomori’s trichrome and mounted in Canada balsam. In addition, some specimens were mounted in a mixture of lactic-acid (LA) and glycerin- ammonium picrate (GAP) and then remounted in Canada balsam as permanent preparations (Mendoza-Franco et al 2013). Parasite identifications were made using a Leica microscope DM2500 with Nomarski interference contrast and based on descriptions provided in the following references: García-Vásquez et al 2007, 2015, Jogunoori et al 2004, Kritsky et al 1989, Lim 1996, Mendoza-Palmero et al 2012, Pariselle and Euzet 1995, Yamaguti 1963.…”

New species of Paracolpenteron n. gen. and Ancyrocephalus (Monogenea, Dactylogyridae) inhabiting the urinary bladder and gills of the Maya needlefish Strongylura hubbsi (Beloniformes, Belonidae) from Chiapas, Mexico

“…Subsequently, parasites preserved in formalin were isolated and stained with Gomori’s trichrome and mounted in Canada balsam. In addition, some specimens were mounted in a mixture of lactic-acid (LA) and glycerine-ammonium picrate (GAP), and then remounted in Canada balsam [25] to obtain measurements and line drawings of haptoral structures and the copulatory complex. All other measurements were obtained from unflattened specimens stained with Gomori’s trichrome stain.…”

“…In Mexico, monogeneans from sites other than the gills and skin of fishes have rarely been studied, with a few dactylogyrid species described and/or recorded, i.e., Enterogyrus malmbergi Bilong Bilong, 1988 in the stomach of the introduced tilapia Oreochromis niloticus (L.) and the native cichlid Cichlasoma callolepis (Regan) (now Thorichthys callolepis ) from Santa Anita Lagoon in the state of Tabasco [13]; Pavanelliella scaphiocotylus Kritsky & Mendoza-Franco, 2003 in the nasal cavity of the catfish Rhamdia guatemalensis (Günther) (Heptapteridae) from a cenote (= sinkhole) in the Yucatán Peninsula [19]; Pseudempleurosoma carangis Yamaguti, 1965 and Pseudempleurosoma gibsoni Santos, Mourão & Cárdenas, 2001 in the rectum of the puffer fish Sphoeroides testudineus (Linnaeus) (Tetraodontidae) and the pyloric ceca of the cobia Rachycentron canadum (Linnaeus) (Rachycentridae), respectively, from the northern coast of the Yucatan Peninsula [27]; and Cacatuocotyle chajuli Mendoza-Franco, Caspeta-Mandujano & Salgado-Maldonado, 2013 in the external surface of the anal opening of the characid Astyanax aeneus (Günther) from the Rio Lacantún basin in the state of Chiapas [25] (see [28]). During studies carried out between February and August 2015 on the parasites of fishes from the Rio Lacantún basin, two undescribed dactylogyrid species were found at two sites in the Maya needlefish Strongylura hubbsi Collette (Belonidae): Paracolpenteron hubbsii n. gen., n. sp.…”