Marbled Spinefoot Siganus Rivulatus Research Articles

Molecular evidence and morphological aspects of Transversotrema licinum, Phyllodistomum hoggettae, and re-description of Gyliauchen volubilis (Digenea) from the Red Sea.

During a recent survey on digenean parasites infecting marine fish captured from water located along the Red Sea off Gizan Coasts, Saudi Arabia, thirty-two (29.09%) out of 110 fish were naturally infected with three different species of digenean parasites. The taxonomical status of the recovered worms was confirmed by light microscopy and molecular analysis. Transversotrema licinum infecting the Haffara seabream Rhabdosargus haffara possessed a transversely elongated body with eyespots and the anterior body margin with delineated velum along with its entire breadth. Oral sucker was absent, and eyespots were paired anterior to or at the level of ventral sucker. Phyllodistomum hoggettae from the urinary bladder of the Arabian Nagil Plectropomus areolatus was differentiated by its elongated body, narrow anterior end widened as going posteriorly with prominent marginal undulations in the hindbody. Gyliauchen volubilis infecting the marbled spinefoot Siganus rivulatus, was with fleshy body, conical, tapered anteriorly, convex dorsally, and concave ventrally. Prepharynx was very long and convoluted and had occupied the greater part of the anterior half of the body. Multiple sequence alignment and phylogeny were based on maximum likelihood analysis for the ITS–2 and 28S rDNA for Transversotrema licinum and Phyllodistomum hoggettae were constructed, respectively. They were compared to species within their families and further deposited into the Genebank under accession numbers MG 722711 and MG722710, respectively.

Risk screening of the potential invasiveness of non-native marine fishes for South Korean coastal waters

Risk screening tools are being increasingly used to identify the potential invasiveness and associated risks of non-native species. In this study, the Aquatic Species Invasiveness Screening Kit was used to evaluate the invasiveness risks of extant and horizon non-native marine fish species for the coastal waters of South Korea. In total, 57 marine fish species were screened and the threshold scores for the Basic Risk Assessment (BRA) and the BRA + Climate Change Assessment (BRA+CCA) (5.5 and 1.5, respectively) reliably distinguished those species carrying a high risk of invasiveness from those carrying a low to medium risk. For both the BRA and BRA+CCA, common lionfish Pterois miles was the highest-scoring species, followed by white perch Morone americana, red drum Sciaenops ocellatus, marbled spinefoot Siganus rivulatus and redcoat Sargocentron rubrum. The outcomes of this study will contribute to the management of non-native marine fish species for the conservation of the native ecosystems in the coastal waters of South Korea.

MORPHOLOGICAL DESCRIPTION OF TWO DIGENEAN PARASITES, FROM LABRIDAE, AND SIGANIDAE HOSTS OF THE RED SEA IN EGYPT

During a parasitological survey on marine fish species inhabiting Hurghada Coasts of the Red Sea, Eighty seven fish specimens of 2 different species were found naturally infected by three different species of digenean parasites, one of them was reported as new host and locality in Egypt. These were Phyllodistomum hoggettae (family: Gorgoderidae) infecting the Arabian mallas Thalassoma klunzingeri (family: Labridae). Body length to width ratio 1:3. Oral sucker opened subterminally. Intestinal bifurcation midway between oral and ventral suckers. Ventral sucker distinctly equal in size to the oral sucker. Testes slightly lobed, oblique, in mid-body; ovary entire, heart shaped, sinistrally posterior to ventral sucker and anterior to testes. Vitelline lobes entire and almost round. Gyliauchen volubilis (family: Gyliauchenidae) infecting the marbled spinefoot Siganus rivulatus (family: Siganidae). Body fleshy, robust, conical, tapered anteriorly, convex dorsally, concave ventrally, with small tail-like protubera-nce postero-dorsal to acetabulum. Prepharynx very long and convoluted, occupied greater part of the anterior body half. Pharynx elongated, prephanyx very coiled and situated close to intestinal bifurcation. Ventral sucker well developed and spherical. Oesophagus very long, wide, longer than body straightened length. Two testes oval, symmetrical, dorsal to ventral sucker, subequal in diameter. Ovary spherical, dextro-submedian between right testis and cirrus sac. Vitelline follicles relatively small, irregular, numerous, extended in lateral fields between testes and mid-oesophageal level, confluent in region of intestinal bifurcation. All of the recovered species were compared with others recorded from different hosts.

Diversity and Length-Weight relationships of Blenniid Species (Actinopterygii, Blenniidae) from Mediterranean Brackish Waters in Turkey

This study aims to determine the species composition and range of Mediterranean Blennies (Actinopterygii, Blenniidae) occurring in river estuaries and lagoon systems of the Mediterranean coast of Turkey, and to characterise the length–weight relationship of the specimens. A total of 15 sites were surveyed from November 2014 to June 2017. A total of 210 individuals representing 3 fish species (Rusty blenny-Parablennius sanguinolentus, Freshwater blenny-Salaria fluviatilis and Peacock blenny-Salaria pavo) were sampled from five (Besgoz Creek Estuary, Manavgat River Estuary, Karpuzcay Creek Estuary, Koycegiz Lagoon Lake and Beymelek Lagoon Lake) of the localities investigated. The high juvenile densities of S. fluviatilis in Karpuzcay Creek Estuary and P. sanguinolentus in Besgoz Creek Estuary were observed. Various threat factors were observed in five different native habitats of Blenny species. The threats on the habitat and the population of the species include the introduction of exotic species, water pollution, and more importantly, the destruction of habitats. Five non-indigenous species (Prussian carp-Carassius gibelio, Eastern mosquitofish-Gambusia holbrooki, Redbelly tilapia-Coptodon zillii, Stone moroko-Pseudorasbora parva and Rainbow trout-Oncorhynchus mykiss) were observed in the sampling sites. In addition to these freshwater species, several lessepsian species (Keeled mullet-Liza carinata, Por's goatfish-Upeneus pori, Goldband goatfish-Upeneus moluccensis, Marbled spinefoot-Siganus rivulatus, Sillago suezensis and Yellowstripe barracuda-Sphyraena chrysotaenia) were observed in the sampling areas.

Ortholinea saudii sp. nov. (Myxosporea: Ortholineidae) in the kidney of the marine fish Siganus rivulatus (Teleostei) from the Red Sea, Saudi Arabia.

Myxozoans, a diverse group of microscopic obligate endoparasites, can cause diseases in a number of economically important fish, including the marbled spinefoot Siganus rivulatus. To date, only 1 myxozoan, Zschokkella helmii, has been reported to infect S. rivulatus. Here we describe another myxozoan detected in S. rivulatus. Investigations of 40 marbled spinefoot fish caught from the Red Sea coast, Jeddah, Saudi Arabia, revealed clusters of parasitic spores in the kidney. Light microscope examination of the native spores revealed sub-spherical, mature spores with smooth shell valves. The 2 polar capsules were equal in size, and the polar filament was perpendicular to the longitudinal axis of the polar capsules. Histopathological examinations of the infected kidneys demonstrated the presence of both spores and developmental stages in the lumen of the renal tubules without any pathological effect. Electron microscopy investigations showed maturing spores composed of 2 valvogenic cells, each with a prominent nucleus. The valvogenic cells enclosed 2 polar capsules containing 3 filament coils as well as a binucleated sporoplasm cell filling the space between and beneath the 2 polar capsules. BLAST search analysis of the amplified sequence from the detected parasite indicated a high percent of identity to the 18S rDNA genes of different myxosporean species. Phylogenetic analysis placed the detected parasite within a clade of Ortholinea sp. (AL-2006). Based on the results of the light and electron microscopy, histopathological, and molecular investigations, the detected parasite was identified as a myxosporean parasite belonging to the genus Ortholinea and designated as O. saudii sp. nov.

Effect of Dietary Protein Level on Growth Performance and Blood Parameters of Marbled Spinefoot Siganus rivulatus

The present study evaluated the effect of dietary protein levels on growth performance and blood parameters of juvenile marbled spinefoot (Siganus rivulatus). Five semipurified, isoenergetic (14.2 MJ digestible energy/kg; 84 g lipids/kg) diets were formulated to contain 30, 35, 40, 45, and 50 g crude protein (CP)/100 g diet. Groups of 15 juvenile fish (7.4 g individual weight) were randomly assigned in triplicate to each of the five treatments and offered the test diets three times daily ad libitum for 9 weeks. Total erythrocyte and differential leukocyte counts, hematocrit, hemoglobin, blood glucose, protein, and serum aspartate aminotransferase and alanine aminotransferase were evaluated. Survival was greater than 95% in all treatments. Maximum growth was observed in fish offered the diet containing 40 g CP/100 g diet crude protein. Differences in dietary protein level had no effect on the hepatosomatic and viscerosomatic indices of the fish, but whole body composition was influenced by diet. Blood parameters showed no physiological or metabolic dysfunctions among fish offered any of the five diets. Findings of the present work strongly suggest that diets containing 40 g CP/100 g and 14.2 MJ digestible energy/kg are suitable for good growth of juvenile spinefoot rabbitfish Siganus rivulatus and do not affect hematological parameters.

Record of Lessepsian marbled spinefoot Siganus rivulatus Forsskal and Niebuhr, 1775 from the Northern Aegean Sea (Izmir Bay, Turkey)

Record of Lessepsian marbled spinefoot <i>Siganus rivulatus </i> Forsskal and Niebuhr, 1775 from the Northern Aegean Sea (Izmir Bay, Turkey)