37. Proterorhinus nasalis (De Filippi, 1863) (Fig. 34), Eastern Tubenose Goby

Gobius nasalis Filippi, 1863: 390; type locality: Caspian Sea near Baku, Azerbaijan; syntypes: BMNH 1869.3 .4.34, MSNG 12655 and 36228; MZUT 672; NMW 33894-96; ZMB 5015 .

Etymology: Latin, nâsus = nose + Latin, - âlis = of or pertaining to.

Distribution and habitat: Inshore habitats, wetlands (e.g., Anzali Wetland) and river mouths of the South Caspian Sea sub-basin from Baku, Azerbaijan south to the middle of the basin (Fig. 27E) (Zarei et al. 2022c).

Remarks: Using mitochondrial COI data, Zarei et al. (2022c) employed a phylogenetic and phylogeographical framework to assess the species level status of Caucasian populations of Proterorhinus, previously classified as P. nasalis . Their results suggest that P. nasalis is a biogeographical relict, distributed in inshore habitats of the South Caspian Sea from Baku (its type locality), Azerbaijan south to the middle of the South Caspian Sea basin, whereas tubenose goby populations from the Sea of Azov, Volga River, and North and Middle Caspian Sea sub-basins, north of Baku have the mtDNA of P. semipellucidus (Kessler, 1877) . The latter freshwater tubenose goby in the northern Caspian Sea Proterorhinus semipellucidus originally was identified with multiple gene nuclear and mitochondrial DNA sequences by Neilson & Stepien (2011).

Material examined: ZM-CBSU S038, 31, Anzali Wetland; ZM-CBSU S052, 2, Khoshkroud mouth ; ZM-CBSU S072, 2, Shalmanroud mouth ; ZM-CBSU S073, 1, Oshmakroud mouth ; ZM-CBSU S074, 1, Boujagh National Park, Gilan Province, Iran .

IUCN: NE. Considering the species narrow geographic range, small population size, and low mtDNA variability, P. nasalis may merit re-examination for an IUCN Red List Threatened Category (i.e., VU, EN or CR) (Zarei et al. 2022c).