Yaeyama Blenny (Ecsenius yaeyamaensis) Care Guide
Ecsenius yaeyamaensis is a small Indo-West Pacific combtooth blenny that grazes algae on shallow coastal reefs.
Compiled by Aquairi from published sources · Published · Updated
Overview
Ecsenius yaeyamaensis (Aoyagi, 1954) is a small combtooth blenny of the family Blenniidae, described from the Yaeyama Islands of southern Japan. According to FishBase it reaches about 6 cm in total length and is widely distributed across shallow coastal reefs of the Indo-West Pacific. It is an algae grazer that lives close to rock and living coral.
Taxonomy
- Family: Blenniidae
- Genus: Ecsenius
- Scientific name: Ecsenius yaeyamaensis (Aoyagi, 1954)
Habitat
FishBase records this species from the Indo-West Pacific, from Sri Lanka to Vanuatu, north to Taiwan and the Yaeyama Islands, and south to the southern Great Barrier Reef. It is a common inhabitant of coastal and inner reef crests with rich coral growth, where adults occur singly or in small groups over boulder and rubble substrates at depths of 0 to 15 m.
Tank requirements
- Minimum tank volume: 80 L (about 21 gal)
- Temperature: 24-26 °C (75-79 °F)
- pH: 8.1-8.4
- Carbonate hardness range (record): 8-12 °dGH
- Lifespan: 3-8 years (KB record)
Diet
FishBase and Wikipedia describe the species as herbivorous, feeding primarily on benthic algae and other plant material scraped from rock and coral surfaces. In aquaria a diet rich in marine algae and herbivore preparations supports this grazing behaviour.
Compatibility
It is a peaceful, bottom-associated fish that spends most of its time perched on rock and substrate. Suitable companions include clownfish, tangs, cardinalfish and wrasses, while large aggressive predators such as lionfish and triggers should be avoided.
Conservation status
IUCN Red List: Least Concern, assessed in 2009. The species is taken for both commercial fisheries and the marine aquarium trade.
Ecsenius yaeyamaensis Breeding Guide
Overview
Ecsenius yaeyamaensis is a combtooth blenny reaching about 6 cm, found on coral reefs in the western Pacific and Indian oceans and listed as Least Concern by the IUCN (Wikipedia). It feeds primarily on benthic algae and weeds and is collected as an aquarium fish. As with the genus generally, it perches on rock and shelters in holes and is rarely if ever captive-bred.
Sexing
Reliable external sexing for E. yaeyamaensis is not documented in the cited sources. In Ecsenius blennies the male tends the eggs, so the breeding male is most often identified behaviourally once he occupies and guards a chosen hole rather than by fixed colour differences.
Conditioning
Conditioning matches the species' herbivorous habit, since it feeds mainly on benthic algae and weeds (Wikipedia). An algae-rich system supplemented with marine vegetable foods and small frozen items, at stable reef parameters and with rock to graze and perch on, supports a pair's spawning condition.
Breeding Setup
A breeding setup provides abundant rock with small holes and crevices that can serve as egg sites, since Ecsenius are crevice-spawning demersal egg-layers. Subdued, mature reef conditions with good algal growth and small caves let a pair claim and defend a nest hole.
Spawning Behavior & Trigger
Ecsenius blennies lay demersal eggs inside a hole or crevice, where the male guards them through development. Species-specific clutch counts and triggers for E. yaeyamaensis 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, spawning has been relatively commonplace but rearing the offspring long proved a futile, heartbreaking endeavour, with the first reported success coming only for the related Ecsenius gravieri (Reef Builders).
Common Challenges
The larval phase is the decisive obstacle. Even with eggs available, raising Ecsenius larvae long eluded breeders, so a dedicated rearing tank, very small first foods and careful water management are essential, and any success for E. yaeyamaensis should be treated as experimental.