Corydoras multiradiatus

Corydoras: from the Ancient Greek κόρυς (korus), meaning ‘helmet’, and δορά (dora), meaning ‘skin, hide of an animal’, in allusion to the rows of bony plates on the flanks of genus members.

multiradiatus: from the Latin multi, meaning 'many', and radiatus, meaning 'radiated', in reference to the high number of dorsal-fin rays in this species.

Native to tributaries of the northwestern Amazon basin in Ecuador and Peru

Type locality is 'Tributary of Río Lagartococha near town of Garza-Cocha, upper Río Napo system, Province Napo, Ecuador'.

The only information provided by Orcés V. is that the type series was collected at 200-250 m AMSL, but this species is likely to form aggregations in smaller tributaries and still bodies of water such as backwaters, oxbows and marginal lakes, similar to closely-related species.

Minimum dimensions of 120 ∗ 45 ∗ 45 cm48 ∗ 18 ∗ 18 in or equivalent are recommended.

Ideally use a substrate of fine sand, although rounded gravel is an acceptable alternative provided it is kept scrupulously clean.

Other décor is largely down to personal choice, but some cover should be provided to give the fish security.

Corydoras spp. are foraging omnivores and will accept most sinking dried foods, as well as small live and frozen varieties such as chironomid larvae (bloodworm), Tubifex, etc.

Feeding a varied diet will ensure the fish are in optimum condition.

Under no circumstances should they be expected to survive on 'left-overs' from other inhabitants of the aquarium or relied on to 'clean' the aquarium.

Peaceful and gregarious. Should be maintained in a group of at least 6-8 individuals.

Adult females are noticeably rounder, higher-bodied, and grow slightly larger than males.

Unreported.

This species was formerly classified in the genus Brochis and is sometimes referred to as ‘long-finned brochis'.

C. multiradiatus can be distinguished from other ex-Brochis species by the extended snout and possession of 17-18 dorsal-fin rays (vs. 10-12 in C. splendens and 15-18, normally 15, in C. britskii). All other members of the genus Corydoras, as well as the closely-related Aspidoras and Scleromystax, possess 6-8 dorsal-fin rays.

Brochis was first synonymised with Corydoras by Britto (2003), since the latter genus cannot be considered monophyletic if the former is accepted as valid. This decision has been supported in subsequent phylogenetic studies by Shimabukuro-Dias et al. (2004) and Alexandrou et al. (2011), although the name Brochis is still common in aquarium literature. It is likely that the genus will be revalidated and expanded in the future following a required taxonomic review of the subfamily Corydoradinae as suggested by Alexandrou and Taylor (2011).

The genus is included in the family Callichthyidae, of which members are often referred to collectively as 'armoured' or 'mailed' catfishes group due to the presence of bony plates in place of scales on the body. Their taxonomy can be confusing, and numerous undescribed species are also thought to exist. Fish of unconfirmed identification entering the aquarium hobby are therefore typically assigned a 'C' or 'CW' number for purposes of reference and organisation.

They are facultative air breathers and possess a modified, highly vascularised intestine which has evolved to facilitate uptake of atmospheric oxygen and aid survival in oxygen-deprived environments. In the aquarium you'll occasionally see them rising to the surface to take in gulps of air.

The stiffened pectoral-fin spines are capable of piercing human skin and a 'sting' can be very painful indeed, so care should be exercised when handling them. It's thought that secretions from the axillary glands at the base of each spine may even be mildly toxic or venomous.