Black Banded Pigmy Boxfish

Occurs on the continental shelf (Ref. 9563).

Capropygia unistriata Kaup

A 2 is poorly subdivided, with no clear-cut separation of parts. It is, however, bipinnate, and could easily have arisen or given rise to the condition in K. aculeatus. There is no intermingling of fibers with the underlying A 1β. A 1β″ is better separated from the more ventral portions of A 1, and originates exclusively from the prootic shelf. The ventral fibers do not intermingle with those of A 3, although they do share the archlike tendon between the maxilla and dentary. The levator and dilatator operculi are smaller. The retractor arcus palatini is continuous with the adductor arcus palatini anteriorly and ventrally, and merely consists of a more anterior-posterior orientation of these muscle fibers. There is no adductor hyomandibulae.

The sternobranchialis has completely separated into two sections, and its origin just overlaps the ventrolateral face of the cleithrum. Levator externus III is not fused to levator IV, but is closely applied to it. Adductor IV is well developed. The adductor superficialis has some fibers originating from the ventral face of the medial process of the cleithrum. The adductor profundus is better developed, and is partly visible posteroventrally behind the coracoid. The supracarinales anterior are fused in the midline, although a septum is present. A single, small inclinator dorsalis passes to the ventrolateral face of the first pterygiophore.

A small inclinator analis arises from the fascia over the obliquus inferioris behind the posteroventral surface of the postcleithrum and attaches to the ventrolateral face of the first anal pterygiophore. Behind this, a thin tendon attaches to the anteroventral base of the first fin ray, and passes posterodorsally. The fibers sweep dorsally in a large semicircle to fade into the fascia beneath the posterior half of the dorsal fin, overlying the epaxialis. The muscle appears to represent an extreme modification of the inclinator of the first anal fin ray.

The bulk of the body musculature consists of the more ventral moiety of the epaxialis. This is well separated from the more dorsal portion, and originates anteriorly from the vertebral column and the fascia over the erectores and depressores dorsales. Posteriorly it forms a tendinous sheath attaching to the bases of all the caudal fin rays (although part of the fibers in the ventral region may be derived from the obliquus superioris. Attachment to the two outermost fin rays is mainly derived from the dorsal and ventral portions of the body musculature, and is tendinous.

Myological Descriptions of Representative Ostraciids

The normal body outline of members of this family is illustrated in Figure 6. Fraser-Brunner (1935, 1941b) recognized seven genera of ostraciids, which he divided (1941b) among two subfamilies. Representatives of four of the seven genera were dissected. These fishes are rather similar to the aracanids, except that the carapace extends behind the base of the anal fin, and, in all but one species, the dorsal fin as well. They are slow swimmers, living on or near coral reefs and sea-grass meadows. Their food is comprised mainly of soft-bodied marine invertebrates, although crabs and other harder bodied organisms are also eaten. The dorsal and anal fins are used for locomotion, being supplemented by the caudal fin in emergencies. Steering is achieved by the pectoral and caudal fins.

As stated above, the ostraciids are considered the more specialized (apomorph) sister group of the aracanids.

Capropygia unistriata, also known as the Black-banded pygmy boxfish, is a species of deepwater boxfish found in the waters over the continental shelf off the southern coast of Australia. It can be found at depths of from 60 to 200 metres (200 to 660 ft). This species grows to a length of 12 centimetres (4.7 in) TL. This species is the only known member of its genus.