Norman O. Dronen, Charles K. Blend, and C. K. Anderson.  2003.  Endohelminths from the brown pelican,  Pelecanus occidentalis, and the American white pelican, Pelecanus erythrorhynchus, from Galveston Bay, Texas, U.S.A., and checklist of pelican parasites. Comparative Parasitology 70(2):140-154.

Ten species of endohelminths including 2 cestodes, 3 nematodes, and 5 trematodes were collected from 6 American white pelicans, Pelecanus erythrorhynchus, and 22 species of endohelminths including 2 acanthocephalans, 3 cestodes, 4 nematodes, and 13 trematodes were collected from 10 brown pelicans, Pelecanus occidentalis, from the Galveston, Texas, area. A mean of 120 and a range of 4 to 2,134 helminths were present in the American white pelican, and a mean of 57 and a range of 2 to 10,413 helminths were found in the brown pelican. Two cestodes, 3 nematodes, and 3 trematodes were common to both species of pelicans. Parvitaenia ibisae, Tetrabothrius sp., Capillaria sp. represent new host records for the American white pelican, and Echinochasmus c.f. donaldsoni, Phagicola macrostoma, and Lyperosomum sp. represent new host records for the brown pelican. Hypotheses for the recent infection of pelicans with species of Bursacetabulus and Bursatintinnabulus along the Gulf coast are discussed.

Charles K. Blend, and N. O. Dronen.  2003.  Bothriocephalus gadellus n. sp. (Cestoda: Bothriocephalidae) from the beardless codling Gadella imberbis (Vaillant) (Moridae) in the southwestern Gulf of Mexico, with a review of species of Bothriocephalus Rudolphi, 1808 reported from gadiform fishes. Systematic Parasitology 54(1):33-42.

Bothriocephalus gadellus n. sp. is described from the intestine of the beardless codling, Gadella imberbis (Gadiformes: Moridae) from the southwestern Gulf of Mexico. It resembles B. scorpii, the type species of Bothriocephalus, and B. manubriformis, the only species of the genus reported from the Gulf of Mexico. B. gadellus n. sp. differs from both species in having four excretory canals on each side of the proglottid (three per side in B. scorpii; two per side anastomosing to form an extensive plexus throughout the medulla in B. manubriformis ), 24-33 testes per proglottid (30-60 in B. scorpii; 60-100 in B. manubriformis), a total length of 31-47 mm (32-950 mm in B. scorpii; 130-1,000 mm in B. manubriformis), and a seminal receptacle and wing-like expansions on each proglottid (absent in B. scorpii and B. manubriformis), as well as lacking two sets of reproductive organs per proglottid (present in B. scorpii) and a vagina with a bulbous sphincter near the opening (present in B. manubriformis). An amendment to the generic diagnosis of Bothriocephalus might be warranted if other species of this genus are found to possess a seminal receptacle.  B. gadellus n. sp. appears to be like those species of Bothriocephalus that can utilise two intermediate hosts (copepod and fish). B. ellipticus and B. neglectus are designated as species inquirendae. This is the first report of a cestode from a morid fish in the Gulf of Mexico, and the first report of a parasite from a species of Gadellus.

Charles K. Blend.  2001.  Life history information on some strigeoids parasitizing pond-raised catfish: A synergism of morphology and molecules.  Doctoral Dissertation.  The University of Southern Mississippi.  251 p.

Portions of the life histories of five strigeoid species parasitizing pond-raised channel catfish (Ictalurus punctatus) in Mississippi and Louisiana are investigated. Detailed morphological observations and DNA sequencing of segments of the COI, 18S rRNA, 28S rRNA, and ITS-1 genes related the diplostomulum with the corresponding adult of four of the five strigeoid species. The encysted prodiplostomulum of Bolbophorus confusus is encapsulated under the skin and in the musculature of the caudal fin base and the head as well as in the mesentery, brain cavity, eye socket, and behind the operculum of the catfish; the adult parasitizes the white pelican (Pelecanus erythrorhynchos). COI sequence data suggests a morphologically indistinguishable adult of a different cryptic species of Bolbophorus in the white pelican. The diplostomulum of Austrodiplostomum compactum is found free in the vitreous humor of the eye of the catfish; the adult parasitizes the double-crested cormorant (Phalacrocorax auritus), and the first intermediate host is a gyro snail (Gyraulus sp.). The diplostomulum of Bursacetabulus pelecanus is found free in the brain of the catfish; the adult infects the white pelican, and the first intermediate host is a gyro snail (Gyraulus sp.). Bursatintinnabulus macrobursus and Bursacetabulus macrobursus are considered junior synonyms of Bursacetabulus pelecanus. Also, Bursatintinnabulus bassanus becomes Bursacetabulus bassanus n. comb. The genus Bursatintinnabulus is suppressed. The unencysted diplostomulum of Hysteromorpha triloba occurred deep within the musculature of the catfish; the adult parasitizes the double-crested cormorant. An unidentified diplostomulum of a species of Diplostomum is found free in the lens of the eye of the catfish; the adult of this species is unknown, but it is believed to parasitize a fish-eating lariform (gull, tern) bird. It is suggested that Diplostomum baeri of Inchausty, Foutz, Heckmann, Ruas, and Ruas, 1997 may not be D. baeri (sensu stricto). Evidence is presented supporting the view that there is more than one species of Diplostomum infecting the lens of the eye of fishes, and the use of the species, Diplostomum spathaceum, as a repository for any form of Diplostomum found in the eye lens of fishes is unfounded.

Charles K. Blend, N. O. Dronen, and H. W. Armstrong.  2000.  Six new species of Lepidapedon Stafford, 1904 (Digenea: Lepocreadiidae) from deep-sea macrourid fishes from the Gulf of Mexico and Caribbean Sea, with revised keys to the species of the genus.  Systematic Parasitology 45(1):29-51.

Species of the genus Lepidapedon are divided into various groups and subgroups based on vitelline distribution relative to the acetabulum and anterior extent of the excretory vesicle.  Members of this genus predominantly parasitise gadiform fishes and are commonly collected from relatively deep waters.  A recent study of deep-sea helminths from macrourids of the Gulf of Mexico and Caribbean Sea revealed six new species of this genus.  L. mexicanensis n. sp., of the elongatum group, elongatum subgroup, differs from other species in this subgroup in proportions (as % of body length), lacking confluent vitelline fields between both the ovary and anterior testis and the testes, and in having a smaller egg and body size.  L. nezumiatis n. sp., of the elongatum group, desclersae subgroup, differs from both L. filiformis and L. desclersae in having intermediate egg and body sizes, and a longer oesophagus than prepharynx.  L. caribbaei n. sp. and L. longivesicula n. sp., of the garrardi group, congeri subgroup, differ from L. congeri in having a sucker ratio of 1:<1.  L. caribbaei n. sp. and L. longivesicula n. sp. differ from each other in that L. caribbaei n. sp. has numerous long, barb-like, deeply imbedded spines, a less elongate body, an infundibuliform oral sucker, a similar-sized oesophagus and prepharynx, and a caecal bifurcation which is closer to the acetabulum than oral sucker, while L. longivesicula n. sp. has shorter, serrate or plate-like, lightly imbedded, widely to sporadically spaced spines, a more elongate body, a spherical to subspherical oral sucker, a longer oesophagus then prepharynx, and a caecal bifurcation which is closer to the oral sucker than acetabulum.  L. desotoensis n. sp., of the rachion group, rachion subgroup, is distinct from both L. luteum and L. abyssensis in having a smaller size, lacking cervical glands or pharyngeal gland cells, and possessing dark-staining particles in the mesenchyme, while it differs from L. abyssensis specifically in having a much longer oesophagus than prepharynx, lateral vitelline fields that are not confluent intertesticularly, and wider eggs.  L. zaniophori n. sp., also of the rachion subgroup, differs from both L. cascadensis and L. genge in having a smaller egg size, a shorter prepharynx and oesophagus then pharynx and vitelline fields that are intertesticular but only slightly encroach between the ovary and anterior testis.  L. sammari and L. spiniferi are designated as incertae sedis, and L. quiloni and L. stromateusi are designated as species inquirendae.  New parasite keys and host records for Coelorinchus coelorhincus, C. caribbaeus and Nezumia cyrano are offered.  Support is given to Lepidapedon probably being the dominant digenean genus in deeper water.

Charles K. Blend, J. S. Franks, R. M. Overstreet, and G. W. Benz.  1999.  Opening a whole new can of worms: Parasites and biology of the snake mackerel (Gempylus serpens: Gempylidae).  A paper presented at The University of Southern Mississippi, Marine and Estuarine Graduate Student Association / Graduate Student Forum 1999 Graduate Student Symposium at the Gulf Coast Research Laboratory, Ocean Springs, Mississippi, March 6.

The snake mackerel, Gempylus serpens, has a tropical and subtropical worldwide distribution.  This unusual-looking fish is characterized by an elongate blackish body, large teeth and eyes, a protruding lower jaw, and finlets that occur behind the dorsal and anal fins.  It is strictly oceanic, migrating vertically daily from the surface to depths below 200m.  We were fortunate to obtain a single female specimen collected off Pensacola, Florida, during a sportfish tournament in August 1998.  The first dorsal spine and gonadal tissue were sectioned to determine it was four years old and mature with early developing oocytes.  Stomach content analysis revealed flatfish.  Thorough examination of the mackerel revealed a diverse parasite fauna: Scolex polymorphus (Cestoda: Tetraphyllidea, plerocercoid); Monilicaecum and possibly Torticaecum (Digenea: Didymozoidae, metacercaria); Gonocerca phycidis (Digenea: Derogenidae, metacercaria); Anisakis sp. (Nematoda: Ascaridoidea, juvenile); and Bomolochus n. sp.? (Copepoda: Bomolochidae, adult).  All parasites represent new host records, since previous reports constitute the hemiurid Dinurus barbatus, acanthocephalan Gorgorhynchus robertdollfusi, and copepod Sarcotretes gempyli.  None of these was from the Gulf of Mexico.  From what is known about the life cycles of these parasites, findings suggest 1) G. serpens feeds on crustaceans and fish at least in the water column, and 2) this fish serves as a paratenic host for helminths utilizing elasmobranchs, large marine teleosts, and toothed cetaceans as final hosts.  Funded in part by NOAA, NMFS, Award No. NA86FL0476.

Charles K. Blend.  1996.  The digenetic trematodes parasitizing macrourid fishes from the Gulf of Mexico and Caribbean Sea: An examination of their systematics, zoogeography and host-parasite ecology.  Master's Thesis.  Texas A&M University.  305 p.

Three hundred and seventy macrourids representing 15 species were examined for digenetic trematodes.  Macrourids were collected from 34 stations in the northwestern to northeastern and southwestern Gulf of Mexico and Caribbean Sea between depths of 13 and 1,600 meters.  The majority of macrourids examined had only been surveyed once before for helminths and two host species herein have never been examined for parasites.  Approximately 44.3% were infected with a total of 740 trematodes (mostly adult) representing seven families, 11 subfamilies, 15 genera and 36 species / morphs.  The systematics of the digeneans in each family were described with taxonomic summaries and remarks concerning established species given.  Three new genera and 13 new species were proposed.  New keys were presented and established ones modified for some of the new species herein and a revision of the genera Allopodocotyle Pritchard, 1966, Apopodocotyle Pritchard, 1966, Neopodocotyloides Pritchard, 1966, Podocotyle Dujardin, 1845, and Podocotyloides Yamaguti, 1934, was suggested.  In decreasing order, Opecoelidae, Ozaki, 1925, Hemiuridae Looss, 1899, Lepocreadiidae Odhner, 1905, and Fellodistomidae Nicoll, 1909, were the dominant families represented.  Prevalence, intensity, mean intensity and relative density / abundance for each species were calculated and compared.  Gonocerca phycidis Manter, 1925, appeared to dominate in these ecological parameters.  Species richness and host specificity were discussed and compared to previous shallow and deep-sea studies.  The relationship between parasite intensities and host characteristics such as sex, mouth position, diet and age were analyzed and discussed.  Zoogeographical affinities both vertically in the water column and worldwide were examined.  Numerous new host records and localities were recorded.  Intrahost infection sites and parasite-induced damage to hosts were discussed.  The most comprehensive listing to date of all known helminths from macrourids and their locations was also presented.  Future avenues of study and discovery were offered.  In summary, the identity and ecological characteristics of the trematodes found in this study appeared to mirror those of previous deep-sea parasite studies from the Gulf of Mexico and from other oceans around the world.

Louise A. Rubec, Charles K. Blend, and Norman O. Dronen.  1995.  Syncoelicotyloides zaniophori n. sp. (Monogenea: Microcotylidae) from the gills of Coryphaenoides zaniophorus (Macrouridae) from the Gulf of Mexico. The Journal of Parasitology 81(6):957-960.

Syncoelicotyloides zaniophori n. sp. (Monogenea: Microcotylidae) is described from the gills of the macrourid fish Coryphaenoides zaniophorus caught in the DeSoto Canyon area in the northeastern part of the Gulf of Mexico.  This new species is differentiated from Syncoelicotyloides macruri Mamaev and Brashovjan, 1989 by its body size, number of testes, length of copulatory organ spines, morphology of immature portion of germarium, size and morphology of egg, and host.

Norman O. Dronen, Charles K. Blend, and John D. McEachran.  1994.  Echinobreviceca coelorhynchae n. gen., n. sp. (Echinobrevicecinae n. subf.), a fellodistomid from Coelorhynchus coelorhynchus (Macrouridae) from the Gulf of Mexico. The Journal of Parasitology 80(2):309-311.

During a study of digenean parasites of deep sea fishes from the Gulf of Mexico, 38% (5 of 13) of Coelorhynchus coelorhynchus Risso, 1810, (Macrouridae) were infected with a total of 33 specimens (6.6/infected fish) of an undescribed species of Fellodistomidae representing a new genus and subfamily.  Other macrourids collected at the same time (Bathygadus macrops Goode and Bean, 1886, Malacocephalus occidentalis Goode and Bean, 1885, and Nezumia aequalis Günther, 1878) were not infected with Echinobreviceca coelorhynchae n. gen., n. sp.  The new species is most similar to members of the subfamily Baccigerinae, but differs in having an I-shaped excretory vesicle, a densely spined tegument, a pretesticular ovary, and a blind seminal receptacle.  Echinobrevicecinae n. subf. is separated from other subfamilies in the family by having an I-shaped excretory vesicle.  Echinobreviceca n. gen. is established as the type and only genus in the new subfamily, and E. coelorhynchae n. sp. as the only known species in the genus.

Charles K. Blend, Norman O. Dronen, and John D. McEachran.  1993.  Buticulotrema stenauchenus n. gen., n. sp. (Digenea: Opecoelidae) from Malacocephalus occidentalis and Nezumia aequalis (Macrouridae) from the Gulf of Mexico. The Journal of Parasitology 79(5):674-676.

Buticulotrema stenauchenus n. gen., n. sp. (Opecoelidae: Opecoelinae) is described from the macrourid fishes Malacocephalus occidentalis Goode and Bean, 1885, and Nezumia aequalis Günther, 1878, collected in June 1971 from the DeSoto Canyon area of the Gulf of Mexico at a depth of 495 m.  Eight of 25 (32%) M. occidentalis and 1 of 8 (13%) N. aequalis examined were infected with the new opecoelid.  Specimens of Bathygadus macrops Goode and Bean, 1886, and Coelorhynchus coelorhynchus Risso, 1810, collected at the same time were not infected with B. stenauchenus.  The new genus most closely resembles Genitocotyle Park, 1937, but differs in that it lacks an accessory sucker behind the genital pore, contains a blind rather than canalicular seminal receptacle, and has a slightly pedunculate acetabulum, a pharynx that is longer than wide, and a distinctive, long necked, bottle shaped body.  Buticulotrema stenauchenus is also similar to Pseudopecoelus von Wicklen, 1946, but the latter lacks a blind seminal receptacle.