No abstract

Based on light and scanning electron microscopical studies, the following five species of philometrid nematodes (Nematoda: Philometridae) are described from marine fishes from off Basrah, southern Iraq (Arabian Gulf): Philometra iraqiensis n. sp. (females) from the abdominal cavity and ovary of the Klunzinger's mullet Liza klunzingeri (Day) (Mugiliformes: Mugilidae), P. megalaspidis n. sp. (females) from the ovary of the torpedo scad Megalaspis cordyla (Linnaeus) (Perciformes: Carangidae), Philometra sp. 1 (females) from the ovary of the greater lizardfish Saurida tumbil (Bloch) (Aulopiformes: Synodontidae), Philometra sp. 2 (females) from the ovary of the bartail flathead Platycephalus indicus (Linnaeus) (Scorpaeniformes: Platycephalidae) and Philometroides eleutheronemae Moravec & Manoharan, 2013 (male and females) from the ovary of the fourfinger threadfin Eleutheronema tetradactylum (Shaw) (Perciformes: Polynemidae). The new species are characterised mainly by the body length, the length and structure of the oesophagus and caudal end and by the family of their fish hosts. The male and the gravid female of P. eleutheronemae are described for the first time; the finding of this species in Iraqi waters represents the first record of this nematode in the region of the Arabian (=Persian) Gulf.

The gills of three of five species of mullets (Teleostei: Mugiliformes: Mugilidae) collected from the brackish and fresh waters of southern Iraq were infected with species of Ligophorus (Monogenoidea: Dactylogyridae) as follows: greenback mullet Chelon subviridis (Valenciennes) infected with Ligophorus lebedevi Dmitrieva, Gerasev, Gibson, Pronkina and Galli, 2012, Ligophorus bantingensis Soo and Lim, 2012, Ligophorus sagmarius n. sp., and Ligophorus fluviatilis (Bychowsky, 1949) Dmitrieva, Gerasev, Gibson, Pronkina, and Galli, 2012; Klunzinger’s mullet Liza klunzingeri (Day) with L. bantingensis, L. fluviatilis, and an apparently undescribed species of Ligophorus; and abu mullet Liza abu (Heckel) with L. bantingensis and L. fluviatilis. The keeled mullet Liza carinata (Valenciennes) and Speigler’s mullet Valamugil speigleri (Bleeker) were uninfected. L. sagmarius n. sp. is described, and L. lebedevi and L. bantingensis are redescribed. Available specimens of L. fluviatilis and the undescribed species of Ligophorus from Klunzinger’s mullet were insufficient for description.

Based on light and electron microscopical studies, the following four species of Philometra Costa, 1845 (Nematoda: Philometridae) are described from marine fishes from off Basrah, southern Iraq (Arabian Gulf): P. brachiri n. sp. (males and females) from the ovary of the Oriental sole Brachirus orientalis (Bloch & Schneider) (Pleuronectiformes; Soleidae), P. piscaria Moravec & Justine, 2014 (female) from the ovary of the orange-spotted grouper Epinephelus coioides (Hamilton) (Perciformes: Serranidae), P. otolithi Moravec & Manoharan, 2013 (male and females) from the ovary of the tigerteeth croaker Otolithes ruber (Bloch & Schneider) (Perciformes: Sciaenidae) and P. tricornuta n. sp. (female) from the musculature of the caudal peduncle of the greater lizardfish Saurida tumbil (Bloch) (Aulopiformes: Synodontidae). Philometra brachiri is mainly characterised by the structure of the distal tip of the gubernaculum and the length of the spicules (132-135 μm) in male. Philometra tricornuta is distinguished by the presence of three large sclerotised oesophageal teeth and two tandem bulbous inflations at the anterior end of oesophagus in female. The female of P. piscaria is described for the first time. Philometra brachiri is the first species of this genus described from a fish belonging to the family Soleidae. The findings of P. piscaria and P. otolithi in Iraqi marine waters represent new geographical records.

A new nematode species, Philometra johnii sp. nov. (Philometridae), is described from male and female specimens found in the ovary of the sin croaker, Johnius dussumieri (Cuvier) (Perciformes, Sciaenidae), in the Arabian Gulf, off the southern coast of Iraq. Based on light and scanning electron microscopical examination, the new species differs from all other gonad-infecting Philometra spp. with dorsal lamella-like structures on the distal tip of the gubernaculum in having a dorsal bipartite protuberance formed by two subdorsal lamellated parts separated from each other by a smooth longitudinal field. This gubernaculum structure is unique among all philometrids. Other distinguishing features include the structure of the male tail, number (6 pairs) and arrangement of genital papillae and the length of spicules (102-153 µm). From eight congeneric, gonad-infecting species with unknown males, the new species can be distinguished by some morphological and biometrical features found in gravid females (absence of caudal projections, length of oesophagus, moderately developed anterior oesophageal inflation, length of first-stage larvae) by the host type (fish family) and geographical distribution. Philometra johnii sp. nov. is the fourth known philometrid species recorded from marine waters of Iraq.