Brachygobius sabanus
Brachygobius sabanus is one of 8 species of goby in the Brachygobius genus, which all share the common name of bumblebee fish or bumblebee goby due to their characteristic black and yellow stripes. Over the past two centuries, efforts to distinguish different species within the Brachygobius genus have occurred within scientific literature; Brachygobius sabanus was described within literature as its own species in 1958, by Robert F. Inger. Other gobies within the genus are B. nunus, B. doriae, B. alcocki, B. sua, B. xanthomelas, B. aggregatus, and B. kabiliensis.
Taxonomy
Brachygobius sabanus belongs to the class Actinopterygii, known as the ray-finned fishes, which encompasses a vast number of fish species and represents half of all living vertebrates on Earth. B. sabanus is part of the order of Gobiiformes, and are further categorized into the genus Brachygobius and species sabanus.Description
Brachygobius sabanus has a very similar appearance to the other goby species in the Brachygobius genus, which all have relatively small bodies and distinctive black and yellow stripes. Fish in the this genus, including B. sabanus, are more cylindrical towards the anterior end of the body, and more compressed towards the posterior end. The head is flattened between the eyes, and the cranial roof sits beneath the dorsal axial muscle. They have two nostrils near the front of their head, and an additional two pore-like nostrils posterior to the first set, close to the eye. As for their dentition, they have caniniform teeth in both their oral jaw and in their pharyngeal jaw.Brachygobius sabanus, in particular, has a yellow body with three black stripes and a black head. The first stripe overlaps with the black head and ends at the anterior half of the first dorsal fin; the last stripe spans down to the mid-ventral line posterior to the base of the anal fin; one additional black stripe sits between these. The first dorsal fin has black coloration at the anterior basal portion. Less than half of the pectoral fins, as well as the pelvic fins, are black. Finally, there is a thin yellow bar along the nape. B. sabanus has large ctenoid scales; there are between 24 and 27 mid-lateral scales and between 0 and 2 predorsal scales on the body, but no scales on the head. It has two dorsal fins, a rounded caudal fin that is no bigger than its head, and, like other gobies in the Brachygobius genus, its pelvic fins are fused together, creating a ventral disc. It can use this disc to attach itself to surfaces vertically and upside-down.
B. sabanus shares the most similar appearance to Brachygobius doriae. Differences between the two species can be found by observing the number of dorsal and anal rays, as well as mid-lateral scales; B. sabanus has more dorsal and anal rays than B. doriae, but fewer mid-lateral scales. These two fish can also be differentiated by their coloration; B. sabanus has small black dots within the light dorsal coloration, known as dark dorsal saddles, which B. doriae does not possess. B. sabanus also shares very similar patterns of lateral-line sensory papillae with other Brachygobius species.