Larval Fish: Blennioidei

The blennioid fishes include five families in the western Atlantic: the Blenniidae, Chaenopsidae, Dactyloscopidae, Labrisomidae, and Tripterygiidae. The most distinctive character of their larvae is a series of short, L-shaped slashes of black pigment along the anal-fin base. They have little or no lateral pigment, and only a few scattered small erythrophores. Most of them have not been identified to species and many of them not even to family. Blennioid larvae were uncommon in our plankton collections except for 1997, when substantial numbers turned up. 1997 was characterized by anomalous weather conditions, possibly associated with the concurrent El Nino event. Winds and currents were light and variable, and the composition of our catches differed noticeably from previous years.

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Blennioidei, USNM 353290

Unidentified blennioid, 11 mm SL, USNM 353290. This specimen shows the typical blennioid characters. The orbital cirrus is present in many blennioids.
Blennioidei, USNM 353872

Unidentified blennioid, 12 mm SL, USNM 353872. This specimen has a predorsal cirrus but lacks an orbital cirrus, a rare combination of characters among local blennioids. One species that does have it, Starksia atlantica, has fewer anal soft rays (15-16) than this specimen (19). Note the three large internal melanophores on top of the gas bladder and the large melanophore on top of the head.
Blennioidei, USNM 353648

Unidentified blennioid, 9 mm SL, USNM 353648. Note the conspicuous gas bladder, the series of small erythrophores along the anal-fin base, and the reddish posterior margin of the hypurals. The specimen has II, 16 anal rays and 29 total dorsal-fin elements; at this size it is difficult to distinguish spines from rays in the dorsal fin.
Blennioidei, USNM 353946

Chaenopsis, (Chaenopsidae), 17.5 mm SL, USNM 353946. The greatly elongate body and numerous fin rays characterize this distinctive genus. The two species, C. ocellata and C. limbaughi have identical fin-ray counts and probably cannot be distinguished as larvae.
Blennioidei, USNM 353948

Gillellus uranidea (Dactyloscopidae), 7.5 mm SL, USNM 353948. Dactyloscopid larvae have a slightly "ski-nosed" dorsal profile of the head from above the eye to the snout. They have neither an orbital cirrus nor a predorsal cirrus. The low anal-fin ray count (22) of this specimen along with its resemblance to the larger larvae described below suggest that it is Gillellus uranidea, a species found in the immediate environs of Carrie Bow Cay.

Blennioidei, USNM 353896

Gillellus uranidea, 8 mm SL, USNM 353896. Compare this to the previous specimen. The reddish dorsal saddles are beginning to develop, and the eye is beginning to migrate dorsally.

Blennioidei, USNM 353896

Gillellus uranidea, 8 mm SL, USNM 353896. Same specimen, dorsal view.

Blennioidei, USNM 346491

Gillellus uranidea, two specimens, 8 mm SL, USNM 346491. Same size but somewhat more developed than the previous specimen; dorsal view, photographed on a black background.

Blennioidei, USNM 346491

Gillellus uranidea, 22 mm SL, USNM 346491. Adult, dorsal view, black background. The illustration of this species in Böhlke and Chaplin's Fishes of the Bahamas shows a pale fish with a few dark spots. Actually, most specimens, at least the ones seen at Carrie Bow Cay, have prominent red saddles across the dorsal surface of the body and posterior head.

Blennioidei, USNM 354573

Malacoctenus (Labrisomidae), 12 mm SL, USNM 354573, reared from larva. The bars extending onto the dorsal fin suggest that this might be M. versicolor. The specimen was collected in the plankton net as a larva and reared through transformation into a juvenile.

Blennioidei, USNM 353653

Starksia atlantica (Labrisomidae), 10 mm SL, USNM 353653. This specimen is beginning to acquire the adult color pattern although it was still planktonic when caught. The lack of an orbital cirrus and the distinctive fin-ray counts (D. XIX, 7; A. II, 15) indicate that it is Starksia atlantica.

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