# Chimaera carophila

Chimaera carophila, the brown chimaera is in the subclass of holocephali. It is a marine cartilaginous fish that resides in the Southwest Pacific Ocean surrounding New Zealand. C. carophila was first observed in 2014. The Brown chimaera has notable features such as large eyes, a relatively short first dorsal fin and spine, a soft rounded snout, and a pale brown body color.

## Distribution

The brown chimaera can be found between depths of 846–1350 m however, they are most commonly found around 1000m in depth. C. carophila are distributed in the plateaus and slopes of deep water near New Zealand. Found in the Southwest Pacific in plateaus such as Challenger Plateau, Chatham Slope and rise, Hikurangi Trough, Campbell Plateau, and Bounty Plateau.

## Distinguishing characteristics

Chimaera carophila differs from C. fulva, C. macrospina, and C. obscura by its geographic distribution, certain morphological characteristics, and coloration. Morphological differences include shorter pelvic claspers, a shorter first dorsal fin, dorsal fin spines are shorter, and a longer caudal dorsal margin and ventral margin.

### Size

The total length of C. carophilia is a minimum of 1035 mm in adulthood with a body length proportion of 599 mm. Adult males total length ranged from 740–975 mm and adult females ranged from 855–1035 mm. Juvenile females' total length ranges from 277–759 mm and juvenile males range from 410–835 mm.

### Coloration

Preserved specimens of the Brown chimaera have a uniform pale brown color however coloration of fresh and live specimens is unknown. From the preserved specimens coloration includes, "a uniform pale brown; faint longitudinal striping visible on tail; ventral snout and mouth darker; grayish-white around upper portion of mouth; pectoral and pelvic fins brownish-purple; first dorsal fin dark brown, sometimes with a purplish hue, darker at posterior margin; second dorsal fin pale brown basally, darker brown distally; caudal and anal fin pale brown; caudal filament beige; adult claspers dark brown-purple with whitish tips; juvenile claspers light brown; spine brown."

## Diet

Chimaera carophila diets primarily consist of benthic-dwelling invertebrates but are also suspected to be detritivorous. One study found benthic invertebrates including gastropods , barnacles, and polychaetes in the stomachs of two specimens. In the same study, they found other fish, cephalopods, and crustaceans in only one of the specimens.

## Life history

Chimaera carophila is oviparous, meaning fertilization occurs internally, and the female sheds a zygote. Species of chimaerids are shown to segregate by sex. Females were found at greater depths than males. Studies show that this could be due to preventing intraspecies competition and sexual conflict. Studies have also found that juveniles are found at greater depths as well. There is not enough information about the reproduction, growth, and development of this species.

## Conservation efforts

IUCN lists C. carophila as Least Concern. Further information is required regarding population size and distribution, but the distribution is considered small. Threats to this species include fishing and harvesting.