First identification of four trypanorhynchid cestodes: Callitetrarhynchus speciouses, Pseudogrillotia sp. (Lacistorhynchidae), Kotorella pronosoma and Nybelinia bisulcata (Tentaculariidae) from Sparidae and Mullidae fish

Abstract

Four previously unrecognized trypanorhynchids are described based on fish specimens from Sparidae and Mullidae host fish of the Red Sea. From September 2010 to June 2011, 66 specimens of the sea bream Pagrus pagrus (F: Sparidae) and 43 of the red mullet Mullus barbatus (F: Mullidae) were purchased from markets in the Suez and Hurghada cities of the Red Sea. The fishes were measured, and their organs investigated for helminth infections. Forty-one (37.6 %) out of the 109 fish specimens investigated were parasitized with Trypanorhyncha metacestodes, identified as Callitetrarhynchus speciouses Linton 1897, Pseudogrillotia sp. Dollfus 1969, Kotorella pronosoma Stossich 1901 from P. pagrus, and Nybelinia bisulcata Linton 1889 from M. barbatus in the mesentery and peritoneal cavity, with prevalences of 16.5, 11.0, 6.0, and 12.0 %. All of these larval stages were encapsulated larvae in blastocysts. C. speciouses is characterized by an elongated scolex, two bothria, a long postbulbosa, and four elongated bulbs. Pseudogrillotia sp. possesses a scolex with two lateral patelliform bothridia; posterior margins are free, not notched. A long sheath was observed, which was irregularly coiled when tentacles invaginated. N. bisulcata possesses an acraspedote scolex with four bothridia, which are broad, bean-shaped. The tentacles are spirally coiled, supplied with hooks with abruptly turned points. The four tentacles sheaths rose from scolex as two anterior (front) and two posterior (back) which overlap at the apices of bulbs. K. pronosoma is characterized by a short body with a craspedote scolex and four bothridia. The tentacles are short and emerge pairwise. The presence of Trypanorhyncha metacestodes in the muscles does not represent a risk of infection for humans. They have a negative effect on fish esthetics. The repugnant aspect and the prohibition for commercial use by sanitary inspectors, however, cause consumer rejection. Parasites of the order Trypanorhyncha have been recorded in these host fishes for the first time.

Morphological, molecular and pathological appraisal of Callitetrarhynchus gracilis plerocerci (Lacistorhynchidae) infecting Atlantic little tunny (Euthynnusalletteratus) in Southeastern Mediterranean

“…7 (7′), while in C. speciosus they are almost equal in size. By morphometrical comparison ( Table 1 ), the parasite from the present study mostly resembles to C. gracilis in Lethrinus nebulosus and in Carangoides malabaricus y [18] , [19] , [36] , [37] , but showing minor variation in the dimensions of the different body parts.…”

“…In Egypt, most of the previous studies were carried out on trypanorhynchids from marine fish in the Red Sea [3] , [17] , [18] , and there are no records for their existence in little tunny from the Egyptian Mediterranean Sea.…”

Morphological and molecular insights of a new species of trypanorhynchid cestode parasite, Nybelinia exostigmi, in the Narrowstripe cardinal fish Apogon exostigma

“…This study is the third report of Nybelinia species from fish from the Gulf of Suez, Red Sea, Egypt. The first report was by Morsy et al (2013) as it reported the presence of Nybelinia narinari and N. bisulcata from Pagrus pagrus. The second report for Palm & Walter (1999) recognized adults of N. africana from Carcharhinus melanopterus.…”

“…Limited studies were done on trypanorhynchids in marine fish from the Red Sea. Egyptian studies include Abdou (2000Abdou ( , 2001Abdou ( , 2005, Abdou & Palm (2008), and Morsy et al (2013). Papers from Saudi Arabia include those of Abu-Zinada (1998) and Toula (1999).…”

Morphology and molecular phylogeny of trypanorhynchid metacestodes infecting commercial fish of the Mediterranean Sea

“…Members of the order Trypanorhyncha Diesing (1863) represent parasitic cestodes of fish and sea invertebrates; adults infect the stomach and intestines of sharks and rays as definitive hosts, while the larval stages are found in the musculature and coelomatic cavity of teleosteans as intermediate hosts (Campbell and Beveridge, 1994;Morsy et al, 2013;Santoro et al, 2020). Detection of these parasites among infected fish poses marketing problems (Morsy et al, 2013). Humans can be accidentally infected by larvae of Trypanorhyncha after ingesting raw fish meat which, in most cases, leads to allergic reactions.…”