Latin name

Dolloidraco longedorsalis

Identification

The body of Dolloidraco longedorsalis is elongated, compressed at the sides, low, its height is about 12-13% of the standard body length. The head is rather large, relatively narrow, its height is approximately equal to or slightly greater than the width of the head, its length is 1.8-2.8 times or 36-56% of the standard length. 

The post-temporal bony ridges on the top of the head are not pronounced. The tip of the lower jaw does not protrude forward. The muzzle is clearly shorter than the horizontal diameter of the orbit. The eye is large, approximately 23-40% of the length of the head. The interorbital space is very narrow, about 4-7% of head length. 

The two lateral lines are the superior (dorsal) and inferior (medial), represented by tubular or punctate bony scales. In the dorsal lateral line, the anterior part with tubular scales is quite long. In the medial lateral line, the posterior, longer section is represented by tubular scales. In the dorsal (upper) lateral line there are 8-18 tubular bony segments (scales) and 0-2 rounded segments, in the medial (middle) lateral line there are 7-20 bony segments. 

In the lower part of the first gill arch, the stamens are arranged in 2 rows; the total number of stamens in the upper part of the arch is 0-5 and 10-15 stamens in the lower part of the arch. Total number of stamens is 34-36. 

The chin tendril is rather long and thin - its relative length is about 30-46% of the head length. The presence of a terminal extension on the antenna in some fishes is probably related to sexual dimorphism.

Features of fish fins

The first dorsal fin is very high, above the base of the gill cover. The second dorsal fin is also high. 

The first dorsal fin has 3-4 soft barbs; the second dorsal fin has 22-25 barbs; the anal fin has 14-16 barbs; the pectoral fin has 16-18 barbs. 

Fish colouring

General colouration pale yellowish brown, darker on the caudal part of the body, without distinct spots. Chin antennas are pale. On the head there are darker areas on the cheeks below the eye and on the gill cover. The dorsal fins are dark. The anal fin is dark at the base and pale along the outer edge. Pectoral fins mostly pale, slightly darker at the base, with indistinct vertical dark stripes. Pelvic fins mostly pale, dark at the base. Caudal fin with a pale background and a dark spot at the base, and a broad dark vertical stripe on the posterior half. Several narrow dark vertical bands may also be present on the fin.

Distribution

Endemic to the high latitudes of the Southern Ocean. The range of the species is characterised as circumpolar-Antarctic and includes the coastal waters of the Antarctic marginal seas around the Antarctic Peninsula, in the Bellingshausen, Weddell, Commonwealth, Davis, Mawson and Ross Seas. 

Habitat

Eurybathy demersal, occurs from the deepened part of the shelf to the continental slope at depths from 202 to 1145 metres.

Size

It is a small species, reaching 137 mm in total length. The maximum recorded weight is 13.90 g.

Behavior

Typically sublittoral-bathyal and typically benthophagous. Occurs in the sublittoral and on the continental shelf. 

Food and feeding habits

The diet studied in the Ross and Weddell Seas consists mainly of free-living polychaetes, as well as sedentary polychaetes and bocoplaves, gammarids and amphipods. In addition, small numbers of cumaceans, mysids, calanoid copepods and hydroids are found in the stomachs of fish.

Reproduction

This species is of no interest to fisheries.

Fishing

Dolloidraco longedorsalis may be caught in bottom trawls in Antarctic coastal waters on the shelf and continental slope.

Relationship with a person

Harmless.