Two new species of Rhinogobius (Gobiiformes: Oxudercidae) from Palawan, Philippines, with their phylogenetic placement

Abstract

Two new species of Rhinogobius found in streams on central part of Palawan Island, Philippines are described. The two new species, Rhinogobius estrellae and Rhinogobius tandikan share unique transverse rows of sensory papillae on the cheek with Rhinogobius similis Gill, 1859, but differ from the latter in fin ray counts, arrangement of the scales, etc. The two new species are distinguished from each other by the pectoral-fin ray count, the longitudinal- and predorsal-scale counts, and colouration of the body. Rhinogobius estrellae new species and R. tandikan new species have been found allopatrically in a stream within Malatgao River system flowing into the Sulu Sea and in the Cayulo River flowing into the South China Sea, respectively. The Malatgao River system is the southernmost habitat of the genus Rhinogobius. Rhinogobius similis had been considered as the only member of the most basal lineage of this genus, but our mitochondrial genome analysis suggested that the two new species are additional members of this lineage. They are considered to be relicts of their common ancestor with R. similis, which probably had a wider distribution.

The complete mitochondrial genome of Rhinogobius szechuanensis (Gobiiformes: Ggobiidae: Gobionellinae)

“… 2020 ; Maeda et al. 2021 ). As shown in Figure 3 , the topological structure of the phylogenetic tree showed that R. szechuanensis and R. rubromaculatus gathered together, and they formed a sister group with the group include R. leavelli , Rhinogobius davidi, and Rhinogobius similis.…”

Characteristic and phylogenetic analyses of mitochondrial genome for Rhinogobius filamentosus (Teleostei: Gobiidae: Gobionellinae), an endemic species in China

“… 2015 ), R. estrellae (Maeda et al. 2021 ), and R. tandikan (Maeda et al. 2021 ), while R. filamentosus , R. duospilus (Tan et al.…”

“… 2021 ), and R. tandikan (Maeda et al. 2021 ), while R. filamentosus , R. duospilus (Tan et al. 2020 ), and other ten species ( R. nagoyae (Maeda et al.…”

“… 2021 ), R. yonezawai (Maeda et al. 2021 ), R. flumineus (Maeda et al. 2021 ), R. formosanus (Yang et al.…”

“… 2021 ), R. flumineus (Maeda et al. 2021 ), R. formosanus (Yang et al. 2020 ), R. cliffordpopei (Wang et al.…”