Brazos Dwarf Crayfish Breeding Guide

How to breed Cambarellus texanus, a tiny Texas dwarf crayfish in which the berried female carries eggs under her abdomen and releases fully formed young.

Overview

Cambarellus texanus is one of the smallest crayfish in the hobby, a member of the genus Cambarellus, a group of small freshwater dwarf crayfish containing roughly 19 species split between Mexico (subgenus Cambarellus) and the Gulf States of the United States (subgenus Pandicambarus, to which C. texanus belongs). It is native to Texas and is a peaceful egg-laying species of beginner breeding difficulty, suited to nano tanks. Its consistently small adult size makes it a calmer alternative to the larger, more aggressive crayfish offered in the trade.

Sexing

As with other crayfish, sexing is done from the underside of the abdomen, where the position of the genital openings differs between males and females. Females are often the more robust of the pair when in condition.

Breeding Setup

Keep within the species range of 18-26 °C and pH 6.5-8.0 over a sand substrate, and supply many small hiding places. A densely furnished tank is important because the young are strongly cannibalistic and require numerous refuges. Its peaceful nature lets it breed in a nano community alongside small fish and shrimp, provided the refuges are abundant enough to keep newly released juveniles separated.

Spawning Behavior & Trigger

After mating the female carries the fertilised eggs under her abdomen, attached to the swimmerets, and tends them by fanning fresh water over the clutch and cleaning them. Dwarf crayfish follow direct development, so there is no free larval stage.

Egg & Fry Care

Depending on temperature the female carries the eggs for several weeks before they hatch into tiny, fully formed copies of the parents that are ready to fend for themselves. Because there is no free-swimming larval stage, no special infusoria culture is needed; the juveniles graze on biofilm and accept the same foods as the adults from the outset. Pregnant females are very sensitive to stress and should not be moved if maximum survival of the young is the goal. Provide abundant cover such as leaf litter or other refuges, since the young are strongly cannibalistic.

Common Challenges

The main difficulties are cannibalism among the young and stress sensitivity of the carrying female. A heavily structured rearing space and avoidance of disturbance during incubation give the best yield.