Wedge Dwarfgoby, Eviota melanosphena Greenfield & Jewett 2016


A Wedge Dwarfgoby, Eviota melanosphena, on the Great Barrier Reef, Australia. Source: Alonso Gonzalez Cabello, Fig. 5, in Greenfield & Jewett (2016) Journal of the Ocean Science Foundation 21. License: CC by Attribution

Summary:
A pygmygoby with a translucent yellowish body crossed by several red-orange bars on the back and upper sides, 9 dark reddish-brown rectangular bars along the lower sides, bars narrowing and becoming darker towards the rear. The last bar is black and extends over most of the caudal peduncle, and is followed by a distinctive triangular to wedge-shaped black mark at the base of the caudal fin, flanked by two dark spots over the procurrent rays.

Cite this page as:
Bray, D.J. 2020, Eviota melanosphena in Fishes of Australia, accessed 30 Mar 2024, https://fishesofaustralia.net.au/home/species/5255

Wedge Dwarfgoby, Eviota melanosphena Greenfield & Jewett 2016

More Info


Distribution

Endemic to the Great Barrier Reef, Queensland, from north of Lizard Island to One Tree Island, in depths of 0-25 m.

Size

A small species of Eviota, almost always less than 13 mm SL.

Colour

Background head colour translucent grey, dark markings on head reddish-brown; vertical line directly under eye, extending down across jaws and under head; second dark mark behind eye at 4 o’clock position; short horizontal mark at 2 o’clock position extending towards nape; two short bars at front of eye extending to upper jaw, one at 7 o’clock and one at 8 o’clock; side of head with roundish blotches, two at lower half and larger blotch at centre of preopercular edge, large blotch covering most of operculum, several small blotches under head. Both jaws and naris tubes reddish-brown. Pupil of eye black, iris silver with spokes of reddish brown radiating out. Several distinct silver-white marks on head: one at 6 o’clock under eye; second at end of lower jaw extending back to dark vertical bar under eye; third between two roundish blotches near preopercular edge; last under horizontal dark bar at 2 o’clock position behind eye. Pectoral-fin base reddish-brown, crossed at centre by narrow silver-white bar, angling dorsoventrally from top of operculum to pectoral-fin base. 
Background colour of body translucent yellowish, dorsal half of body lighter crossed by several red-orange bars extending from midline up to dorsum, two of these as bars crossing nape. Ventral half of body with 9 dark reddish brown rectangular bars, three over abdomen widest, narrowing posteriorly and becoming darker. Ninth bar black and extending over most of caudal peduncle, ventral margin of other postanal bars black. Ninth bar followed by triangular to wedge-shaped black mark centrally at base of caudal fin and overlapping end of hypural plate. 
Ventral surface under head, breast, and abdomen translucent grey. 
First dorsal-fin membranes clear centrally, distal margin dusky, and basal one-quarter red-orange extending up from body, spines with alternating black and white sections. Second dorsal fin similarly marked to first. Caudal fin crossed by rows of black dots, its margin dusky. Anal fin light basally, remainder black. Pectoral and pelvic fins translucent grey

Similar Species

This species has been confused with the Finespot Eviota, Eviota punctulata, which also occurs on the Great Barrier Reef.

Etymology

The specific name melanosphena is from a Latinized Greek melanos (= black), and sphena (= wedge), in reference to the dark, wedge-shaped mark at the base of the caudal fin.

Species Citation

Eviota melanosphena Greenfield & Jewett 2016, J Ocean Sci. Foundation 21: 72, figs 1-5. Type locality: Sand Cay, on top of reef, north of Lizard Island, Great Barrier Reef, Australia, 0–3 m.

Author

Bray, D.J. 2020

Resources

Atlas of Living Australia

Wedge Dwarfgoby, Eviota melanosphena Greenfield & Jewett 2016

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.L. & Jewett, S.L. 2016. Eviota melanosphena, a new dwarfgoby from Australia (Teleostei: Gobiidae). Journal of the Ocean Science Foundation 21: 71-77. http://dx.doi.org/10.5281/zenodo.55695

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

Quick Facts


CAAB Code:37428441

Depth:0-25 m

Habitat:Reef associated

Max Size:1.3 cm SL

Native:Endemic

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Species Maps

CAAB distribution map