Twospot Eviota, Eviota bimaculata Lachner & Karnella 1980


Other Names: Twin-occipital Dwarfgoby, Twospot Fringedfin Goby, Twospot Goby

A male Twospot Eviota, Eviota bimaculata, at Rockingham, Western Australia, May 2022. Source: henrycarrick / iNaturalist.org. License: CC by Attribution-NonCommercial

Summary:
A small cryptic goby with two large black spots behind each eye, many smaller reddish spots on the head and body below the first dorsal fin, several short narrow vertical black marks along the midside, narrow pale bars along the back, five or six faint internal vertical bars along the anal-fin base, and a small black spot below skin on middle of caudal peduncle. The pelvic fins are separate, with fringe-like rays, and males have an elongate first dorsal-fin spine.

Cite this page as:
Bray, D.J. 2022, Eviota bimaculata in Fishes of Australia, accessed 02 Dec 2022, https://fishesofaustralia.net.au/home/species/1344

Twospot Eviota, Eviota bimaculata Lachner & Karnella 1980

More Info


Distribution

Ceduna, South Australia, to North West Cape, Western Australia. Inhabits coastal rocky and coral reefs. Although somewhat common, this species is rarely seen due to its small size and cryptic behaviour.

Features

Dorsal fin VI + I, 9; Anal fin I, 8; Caudal fin (segmented rays) 19; Pectoral fin 16-17; Pelvic fin I, 4-5.
Head and body compressed; interorbital narrow, much less than eye diameter; mouth oblique, small, rear end of jaws under middle of eyes; sensory pore by each posterior nostril, two median pores between eyes and two pores behind each eye; two pores on posterior preopercular margins; gill openings restricted to pectoral fin bases; tongue tip pointed. 
Head naked; body covered with ctenoid scales, in 24-26 vertical rows; pectoral fin bases and area before ventral fins without scales. 
Two dorsal fins, first dorsal with rounded margin, males with filamentous first spine, first dorsal originating just behind ventral fin insertion; second dorsal origin just behind first dorsal fin; anal fin origin below and just behind second dorsal origin; caudal fin with rounded margin. Pectoral fins large, diamond shaped. Pelvic fins separate, origins below pectoral fin insertions, soft rays fringe-like, innerconnected only at bases of rays, fifth ray in each fin very short or absent.

Colour

Translucent in life; two large black spots behind each eye; numerous smaller black spots on head and anteriorly on body below first dorsal fin; several short thin vertical black marks on each side of body; body with five or six faint vertical bars below skin along second dorsal base and base of anal fin, and ventrally on caudal peduncle; small black spot below skin on midside just before caudal fin; first dorsal fin dark.grey to black; second dorsal and anal fins with scattered small black spots; anal fin grey to black; pectoral and pelvic fins clear to white.

Etymology

The specific name bimaculata is from the Latin bi- (= two) and maculata (=spotted) in reference to the pair of prominent dark occipital spots, one on each side of the head.

Species Citation

Eviota bimaculata Lachner & Karnella 1980, Smithson. Contrib. Zool. 315: 91, figs 50-52. Type locality: Rottnest Island, Western Australia.

Author

Bray, D.J. 2022

Resources

Atlas of Living Australia

Twospot Eviota, Eviota bimaculata Lachner & Karnella 1980

References


Greenfield, D.W. 2017. An overview of the dwarfgobies, the second most speciose coral-reef fish genus (Teleostei: Gobiidae: Eviota). Journal of the Ocean Science Foundation 29: 32-54. http://dx.doi.org/10.5281/zenodo.1115683

Greenfield, D.W. & Winterbottom, R. 2016. A key to the dwarfgoby species (Teleostei: Gobiidae: Eviota) described between 1871 and 2016. Journal of the Ocean Science Foundation 24: 35–90. http://dx.doi.org/10.5281/zenodo.219620

Hoese, D.F. & Larson, H.K. 1994. Family Gobiidae. pp. 781-810, figs 690-714 in Gomon, M.F., Glover, C.J.M. & Kuiter, R.H. (eds). The Fishes of Australia's South Coast. Adelaide : State Printer 992 pp. 810 figs. 

Hoese, D.F. & Larson, H.K. 2008. Family Gobiidae. pp. 749-773 in Gomon, M.F., Bray, D.J. & Kuiter, R.H. (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp. 

Hoschke, A., Whisson, G. & Moore, G.I. 2019. Complete list of fishes from Rottnest Island. pp. 150-161 in Whisson, G. & Hoschke, A. (eds) The Rottnest Island fish book. 2nd ed. Perth : Aqua Research and Monitoring Services.

Hutchins, J.B. & Swainston, R. 1986. Sea Fishes of Southern Australia. Complete field guide for anglers and divers. Perth : Swainston Publishing 180 pp. 

Hutchins, J.B. & Thompson, M. 1983. The Marine and Estuarine Fishes of South-western Australia. Perth : Western Australian Museum 103 pp. 345 figs.

Lachner, E.A. & Karnella, S.J. 1980. Fishes of the Indo-Pacific genus Eviota with descriptions of eight new species (Teleostei : Gobiidae). Smithsonian Contributions to Zoology 315: 1-127 figs 1-66 https://doi.org/10.5479/si.00810282.315

Larson, H. 2019. Eviota bimaculata. The IUCN Red List of Threatened Species 2019: e.T141482327A149305945. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T141482327A149305945.en. Downloaded on 18 January 2021.

Suzuki, T., Greenfield, D.W. & Motomura, H. 2015. Two new dwarfgobies (Teleostei: Gobiidae) from the Ryukyu Islands, Japan: Eviota flavipinnata and Eviota rubrimaculataZootaxa 4007(3): 399-408. https://doi.org/10.11646/zootaxa.4007.3.6


Whisson, G. & Hoschke, A.  2021. The Perth coast fish book. Identification guide Mandurah to Two Rocks. Perth : Aqua Research and Monitoring Services, 290 pp.

Quick Facts


CAAB Code:37428117

Conservation:IUCN Least Concern

Depth:1-10 m

Habitat:Reef associated

Max Size:2.5 cm TL

Native:Endemic

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