The convict julie (''Julidochromis regani'') is a

cichlid Cichlids () are a large, diverse, and widespread family of percomorph fish in the family Cichlidae, order Cichliformes. At least 1,760 species have been scientifically described, making it one of the largest vertebrate families, with on ...

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

in the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Pseudocrenilabrinae The Pseudocrenilabrinae are a subfamily in the cichlid family of fishes to which, according to a study from 2004, includes all the Middle Eastern and African cichlids with the exception of the unusual '' Heterochromis multidens'' and the Malaga ...

family endemic to

Lake Tanganyika Lake Tanganyika ( ; ) is an African Great Lakes, African Great Lake. It is the world's List of lakes by volume, second-largest freshwater lake by volume and the List of lakes by depth, second deepest, in both cases after Lake Baikal in Siberia. ...

. Hence it is found in

Burundi Burundi, officially the Republic of Burundi, is a landlocked country in East Africa. It is located in the Great Rift Valley at the junction between the African Great Lakes region and Southeast Africa, with a population of over 14 million peop ...

, the

Democratic Republic of the Congo The Democratic Republic of the Congo (DRC), also known as the DR Congo, Congo-Kinshasa, or simply the Congo (the last ambiguously also referring to the neighbouring Republic of the Congo), is a country in Central Africa. By land area, it is t ...

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

, and

Zambia Zambia, officially the Republic of Zambia, is a landlocked country at the crossroads of Central Africa, Central, Southern Africa, Southern and East Africa. It is typically referred to being in South-Central Africa or Southern Africa. It is bor ...

. The fish is named after

Charles Tate Regan Charles Tate Regan (1 February 1878 – 12 January 1943) was a British ichthyology, ichthyologist, working mainly around the beginning of the 20th century. He did extensive work on fish classification schemes. Born in Sherborne, Dorset, he was ...

. This species is closely related to ''

Julidochromis marlieri ''Julidochromis marlieri'' is a species of cichlid endemic to Lake Tanganyika where it is only known from the northwestern portion preferring rocky shorelines in deep waters. In the aquarium trade, it is commonly known as Marlier's Julie, Spotted ...

''. Possibly, a male common ancestor of these two

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two diff ...

ised with some female ''

Telmatochromis __NOTOC__ ''Telmatochromis'' is a small cichlid genus of the subfamily Pseudocrenilabrinae. These ray-finned fishes are endemic to the Lake Tanganyika basin (mostly in the lake itself, but also its outflow river Lukuga) in Africa. Systematics A ...

'' ancestor in their

evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

ary past. (2007): Phylogenetic relationships of the Lake Tanganyika cichlid tribe Lamprologini: The story from mitochondrial DNA. '' Mol. Phylogenet. Evol.'' 45(2): 629–642. (HTML abstract)

Description

''Julidochromis regani'' is a small (up to TL)

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

. Its pale to golden yellow body is slender and elongated. A varying black stripe pattern, depending on which part of the lake the fish originates from, is present. However, ''Julidochromis regani'' all have four slender

lateral Lateral is a geometric term of location which may also refer to: Biology and healthcare * Lateral (anatomy), a term of location meaning "towards the side" * Lateral cricoarytenoid muscle, an intrinsic muscle of the larynx * Lateral release ( ...

black stripes that run the length of the body, although some variations have the fourth stripe exclusively on the head. On the

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

the stripes are vertical. The outer edge of the

caudal Caudal may refer to: Anatomy * Caudal (anatomical term) (from Latin ''cauda''; tail), used to describe how close something is to the trailing end of an organism * Caudal artery, the portion of the dorsal aorta of a vertebrate that passes into th ...

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

and

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

s is white, while the

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

s are yellow. Sexing is difficult, but males do have a small

genital papilla The genital papilla is an anatomical feature of the external genitalia of some animals. In mammals In mammals, the genital papilla is a part of the vulva not present in humans, which appears as a small, fleshy flab of tissue. The papilla covers the ...

and females are generally plumper than the male.

Ecology

It is

omnivorous An omnivore () is an animal that regularly consumes significant quantities of both plant and animal matter. Obtaining energy and nutrients from plant and animal matter, omnivores digest carbohydrates, protein, fat, and fiber, and metabolize ...

. Pairs are largely monogamous, though instances of

polyandry Polyandry (; ) is a form of polygamy in which a woman takes two or more husbands at the same time. Polyandry is contrasted with polygyny, involving one male and two or more females. If a marriage involves a plural number of "husbands and wives ...

, with the female taking more than one mate, have been recorded in both the wild and the aquarium. It is a secretive biparental substrate spawner, retreating to caves or rock crevices for protection and breeding.

In the aquarium

''Julidochromis regani'' are small-growing

dwarf cichlid Dwarf cichlid is a term used by fishkeeping hobbyists to describe an arbitrary assemblage of small-sized fish from the family Cichlidae. Although the grouping is widely used in the aquarium industry and hobby, the grouping has no taxonomic or eco ...

s and easy to spawn and care for if their basic needs are fulfilled. Like all

cichlids, ''Julidochromis regani'' are best maintained in hard

alkaline In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The ...

water, with a pH of 8.5 - 9.0 and a hardness of 12-14 kH, and in aquaria no smaller than . Only one species of ''

Julidochromis ''Julidochromis'' is a genus of cichlids in the subfamily Pseudocrenilabrinae. They are commonly called julies and are endemic to Lake Tanganyika in eastern Africa. This genus includes six formally described species, some with a number local v ...

'' should be kept in any single aquarium, as the species within this genus tend to hybridise easily. Hybridisation with ''

Chalinochromis ''Chalinochromis'' is a small cichlid genus from the subfamily Pseudocrenilabrinae. These ray-finned fishes are endemic to Lake Tanganyika in the East African Rift. The scientific name refers to the bridle-like markings across the heads of member ...

'' (which might belong in ''Julidochromis'') and ''

'' is suspected, and it is common enough in

Lamprologini Lamprologini is a tribe of African cichlid fishes. It contains seven genera and nearly 100 species. Over half of the species in this tribe are in the large genus ''Neolamprologus''. Most genera in the tribe are endemic to Lake Tanganyika, but on ...

to better avoid keeping more than one species of this

tribe The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

per aquarium. The tank should be decorated with rocks to form caves and passageways as shelter; like many other Rift Valley cichlids, they tend to be territorial and somewhat aggressive. It is therefore best to keep them with other cichlids to defuse their rowdy behavior. Fry can stay with the parents and should be fed protein-rich foods such as baby brine shrimp. Parents can sometimes be found leading their fry around the aquarium. Breeding is, as usual in these social and intelligent fishes, easiest achieved by acquiring a stock of juveniles and letting them grow up together until pair-bonds are established.

Description

Ecology

In the aquarium

References

Further reading