Ecsenius pulcher Breeding Guide

Ecsenius pulcher is a western Indian Ocean combtooth blenny that lays demersal eggs in rock crevices under male care. This guide covers pairing, conditioning and spawning, with a warning that larval rearing for Ecsenius is barely established.

Overview

Ecsenius pulcher is a combtooth blenny of the western Indian Ocean, described by Murray in 1887 and listed as Least Concern by the IUCN (Wikipedia). Like other members of the genus Ecsenius it is a small, bottom-associated reef fish that perches on rock and shelters in holes, grazing benthic algae and weeds. It enters the aquarium trade but is rarely if ever captive-bred.

Sexing

Reliable external sexing for E. pulcher is not documented in the cited sources. In Ecsenius blennies generally, the male takes charge of the eggs, so the breeding male is most often identified behaviourally once he is occupying and guarding a chosen hole rather than by fixed colour differences.

Conditioning

Conditioning suits the genus's grazing habit: Ecsenius blennies feed largely on benthic algae and weeds, so an algae-covered system supplemented with marine vegetable foods and small frozen items keeps a pair in condition. Stable reef parameters and plentiful rockwork to graze and perch on support spawning readiness.

Breeding Setup

A breeding setup provides abundant rock with small holes and crevices that the fish can claim as egg sites, since Ecsenius are crevice-spawning demersal egg-layers. Subdued, mature reef conditions with good algae growth and small caves let a pair establish a guarded nest hole.

Spawning Behavior & Trigger

Ecsenius blennies are demersal egg-layers: the eggs are deposited inside a hole or crevice and the male guards them through development. Species-specific clutch counts and exact triggers for E. pulcher are not documented in the cited sources and so are omitted, with stable conditions and good condition generally underpinning spawning.

Egg & Fry Care

The male tends the attached eggs in the crevice until hatching, after which the larvae are planktonic. For the genus Ecsenius, while spawning has been relatively commonplace, rearing the offspring long proved a futile, heartbreaking endeavour, and the first reported success came only with the related Ecsenius gravieri (Reef Builders).

Common Challenges

The decisive obstacle is the larval phase. Even with eggs readily available, raising Ecsenius larvae eluded breeders for years, so a dedicated rearing tank, very small first foods and meticulous water management are essential, and success should be treated as experimental for E. pulcher.