Community structure of intestinal adult trematodes (Platyhelminthes) in six species of Haemulon (Osteichthyes) in Puerto Morelos Reef National Park, Quintana Roo, Mexico

SPATIAL VARIATION IN HELMINTH PARASITE COMMUNITIES OF THE FRENCH GRUNT, HAEMULON FLAVOLINEATUM (TELEOSTEI: HAEMULIDAE), FROM THE YUCATAN PENINSULA

The French grunt, Haemulon flavolineatum, is an abundant fish and a good model for studying parasite communities. Specimens were collected at 4 localities between the Campeche Bank (within the Gulf of Mexico) and the Mexican Caribbean Sea to describe and compare the differences and similarities between localities and regions in the communities of parasitic helminths. Thus, we calculated the Hill numbers associated with species richness (q = 0) and the dominance estimator (q = 2) using rarefaction and extrapolation curves to provide asymptotic estimators of diversity. A 2-way PERMANOVA was used to determine whether there was a significant difference in parasite assemblage structure between localities or regions. A total of 11 helminth taxa (species level) were recorded in 104 individuals of H. flavolineatum, consisting of 8 digenean trematodes species, 2 acanthocephalan species, and 1 nematode species. Our findings include new reports of 7 parasite taxa and new geographical records for some parasites in H. flavolineatum. The highest dissimilarities in parasite composition were observed between the most distant locations (Banco Chinchorro vs. Cayo Arcas) that were each located in different regions. Species richness was similar between regions, although the most dominant helminths were Postmonorchis orthopristis and Dollfustrema sp. in the Mexican Caribbean and Campeche Bank regions, respectively. Future studies should explore how patterns in parasite community structure are affected by currents running south to north by the Yucatan Current through the Yucatan Channel and easterly to Campeche Bank.

Monorchiids (Digenea, Trematoda) of fishes in the Yucatán Peninsula, Mexico, with the description of three new species based on morphological and molecular data

Adult specimens of monorchiids (Digenea) were collected from the intestines of the white grunt, Haemulon plumierii Lacepède (Haemulidae), and the white mullet, Mugil curema Valenciennes (Mugilidae) from five localities off the Yucatán Peninsula and one locality in the Gulf of Mexico. Some specimens were photographed and sequenced for two molecular markers, the large subunit (LSU) of nuclear rDNA and the cytochrome c oxidase subunit 1 (cox1) of mitochondrial DNA. Other specimens were processed for morphological analyses. Newly generated sequences were aligned with other sequences available in GenBank. Bayesian inference and maximum likelihood analyses were implemented using the data sets of LSU and cox1 independently. Reciprocal monophyly evidenced through phylogenetic analyses, sequence divergence values for both molecular markers, and detailed morphological analyses, including scanning electron microscopy photomicrographs, revealed three new genetic lineages, i.e., species, as parasites of M. curema. The three new species are Sinistroporomonorchis mexicanus n. sp., Sinistroporomonorchis yucatanensis n. sp., and Sinistroporomonorchis minutus n. sp. Two additional species of monorchiids were sampled, characterised molecularly, and re-described, namely Sinistroporomonorchis glebulentus (Overstreet, 1971) from the white mullet, and Alloinfundiburictus haemuli (Overstreet, 1969), from the white grunt.

Rediscovering Monogenoids (Platyhelminthes) Parasitizing Pomacentrid and Chaetodontid Fishes from Cayo Arcas Reef, Gulf of Mexico

During a research of gill ectoparasites on damselfishes (Pomacentridae) and butterflyfishes (Chaetodontidae) from the Cayo Arcas reef in the Campeche Bank (Gulf of Mexico), the following monogenoids (Platyhelminthes) were found: Paraeuryhaliotrema pomacentris n. gen., n. sp. (Dactylogyridae) on beaugregory Stegastes xanthurus (Poey, 1860) (Pomacentridae) that is characterized, in part, by possessing a haptor armed with a dorsal, ventral anchor-bar complexes, seven pairs of similar hooks; two pairs of eyespots; overlapping gonads; a copulatory complex composed of a male copulatory organ (MCO) and an accessory piece; MCO tubular with a bulbous base from which arises a coiled shaft in the clockwise direction; and a dextral vaginal pore; Neohaliotrema variabilis n. sp. on bicolor damselfish Stegastes partitus (Poey, 1868) (type host), beaugregory Stegastes xanthurus (Poey, 1860) and beaugregory Stegastes leucostictus (Müller & Troschel, 1848); Neohaliotrema manubrium n. sp., Neohaliotrema aliamanubrium n. sp. and Neohaliotrema bifidum n. sp., Neohaliotrema bychowskii Zhukov, 1976 and Neohaliotrema macracanthum Zhukov, 1976 on Sergeant-major Abudefduf saxatilis (Linnaeus, 1758) (Pomacentridae); Neohaliotrema similium n. sp. on S. xanthurus; Haliotrema brevicirrus Zhukov 1976 on spotfin butterflyfish Chaetodon ocellatus Bloch 1787 (Chaetodontidae); Microcotyle multilineatus n. sp. (Microcotylidae) on brown chromis Chromis multilineata (Guichenot 1853) (Pomacentridae). The new species are described and illustrated; new illustrations and measurements of the haptoral structures, and new redescription and illustrations are provided for N. bychowskii, N. macracanthum and H. brevicirrus, respectively. The present study represents the first knowledge about ectoparasitic monogenoids of fishes in the Cayo Arcas reef from the Gulf of Mexico.