Turcinoemacheilus ekmekciae, a new dwarf loach from upper Tigris and Euphrates (Teleostei: Nemacheilidae).

Turcinoemacheilus ekmekciae, new species, from upper Euphrates and Tigris drainages is distinguished from other species of Turcinoemacheilus in Western Asia by having a dark stripe broader than the eye diameter along the lateral line, rarely possessing roundish blotches, 5-6 mandibular pores in mandibular canal, a comperatvely smaller head, a deeper body, and a greater pre-pelvic distance. Our specimens collected from the upper Great Zab, near the type locality of Turcinoemacheilus kosswigi, showed notable genetic divergence (a minimum K2P of 3.3%) from sequences reported as T. kosswigi in previous studies. Despite morphological similarities, this molecular difference suggests that the populations analysed in previous studies may represent a potential new species of Turcinoemacheilus, which we tentatively named as Turcinoemacheius cf. kosswigi. Molecular data also suggest that T. ekmekciae is characterized by a minimum K2P distance of 3.5% from Turcinoemacheilus minimus and T. cf. kosswigi. The three methods for species delimitation (assemble species by automatic partitioning [ASAP], Poisson tree processes [PTP], and multi-rate PTP [mPTP]) that were utilized for testing species assignments consistently identified our test group as a distinct species.

Plastics in an endemic fish species (Alburnus sellal) and its parasite (Ligula intestinalis) in the Upper Tigris River, Türkiye.

Occurrence of micro-, meso- and macroplastics in Alburnus sellal and its parasite Ligula intestinalis is reported for the first time in the Tigris River, one of the two large rivers that defines Mesopotamia. Plastic occurrence was assessed from museum fish materials collected in the upper Tigris River between 2007 and 2021. Plastics were found in 57 % of A. sellal specimens (536 individuals) and in 74 % of L. intestinalis specimens (57 individuals). Mean plastic ingestion was 1.27 ± 1.30 items. fish-1 and 1.77 ± 1.79 items. parasite-1 considering all the fish and parasites analysed. Fibres were the most common types of plastics, comprising 96.2 % and 81 % of plastics in A. sellal and L. intestinalis, respectively. Black was the most common colour of plastics found in both fish (37 %) and parasite specimens (58 %). Microplastics comprised 95.5 % and 100 % of plastics found in A. sellal and L. intestinalis, respectively. In both specimens acrylic (PAN) was the most common polymer as confirmed by FTIR spectroscopy. Differences in plastic ingestion were not significantly over time and among regions. No significant correlation was found between plastics ingestion by fish and by parasites. The present assessment shows that native fish species of the Tigris River have been contaminated by plastics by more than a decade. Our results contribute to a better understanding of the status of plastic pollution in fish and parasites, provide plastic pollution baseline data for the Tigris River and highlight the urgent need to elucidate on the distribution and fate of plastics in freshwater environments and their effects on the ecosystem and humans.

Alburnoides diclensis (Actinopterygii: Cyprinidae), a new species of cyprinid fish from the upper Tigris River, Turkey.

Alburnoides diclensis sp. n. is described from the Tigris River drainages (Persian Gulf basin) in southeastern Anatolia, Turkey. It is distinguished by a combination of the following characters (none unique to the species): a poorly developed ventral keel between pelvic and anal fins, completely scaled or rarely without one scale in front of anus; head short (length 24-27% SL), its upper profile markedly convex on level of nostril; mouth terminal, with marked chin; lips equal to or upper lip slightly longer than lower lip; snout with rounded tip, its length equal to or greater than eye diameter but smaller than interorbital distance; body moderately deep (depth at dorsal-fin origin 25-30% SL); anal-fin depth 1.2-1.4, mean 1.3 times in HL; 48-53 lateral-line scales, 12½-15½ branched anal-fin rays; 41-42 total vertebrae, comprising 20-21 abdominal and 20-21 caudal vertebrae.

Salmokottelati, a new species of trout from Alakir Stream, draining to the Mediterranean in southern Anatolia, Turkey (Teleostei, Salmonidae).

Salmokottelati sp. n., is described from Alakir Stream (Mediterranean basin) in Turkey. It is distinguished from other Anatolian Salmo species by a combination of the following characters (none unique to the species): general body colour greenish to silvery in life; 7-9 parr marks along lateral line; four dark bands on flank absent in both sexes; black ocellated spots few, present only on upper part of flank in individuals smaller than 160 mm SL but in larger both males and females black spots numerous and located on back and middle and upper part of flank; red spots few to numerous, scattered on median, and half of lower and upper part of flank; head long (length 29-33% SL in males, 26-32 in females); mouth large (length of mouth gape 13-19% SL in males, 12-15 in females); maxilla long (length 10-13% SL in males, 8-12 in females); 105-113 lateral line scales; 24-29 scale rows between lateral line and dorsal-fin origin, 17-19 scale rows between lateral line and anal-fin origin; 13-15 scales between lateral line and adipose-fin insertion.