Helostoma temminkii
Green kisser
(Also: Green kissing gourami; Kissing gourami; Pink kisser)

Helostoma temminkii, also known as the kissing gourami, is naturally found in Southeast Asia in Thailand, Indonesia, Sumatra, Borneo, and Java. Due to tropical fish breeding for the aquarium trade, it has also been reported in Florida but is not yet established. (Christensen, 1992; Courtenay and Stauffer, 1991)

Helostoma temminkii is a freshwater fish that prefers the sluggish or standing water of tropical lakes, canals, swamps, and ponds, and water temperatures between 22 and 30˚C. During the rainy season these fish migrate through rivers to shallow lakes and floodplains to spawn. They are usually found near the surface of the water because of their ability to breathe air. (Christensen, 1992; Rainboth, 1996)

Helostoma temminkii has a rounded caudal fin and a dorsal fin that is longer than the anal fin. It has an interrupted lateral line and a smooth-edged operculum and sub operculum. In the wild its typical length is around 20 cm but it can reach a maximum length of 30 cm. The most notable feature of kissing gourami are mouths with very strong, fleshy lips that can be stretched forward to "kiss" things like rocks, plants, food, and each other. They have no teeth on the palate or jaws, but they do have hundreds of small rust colored mucous membrane teeth that are covered with enamel. Fish sold for aquariums are usually an artificially produced pink color. Wild forms are gray to green with a dark bar along the base of the caudal fin. (Axelrod, et al., 1971; Garant, 1969; Sakurai, et al., 1993; Sterba, 1983; Trapani, 2001)

Fertilized eggs attach to the underside of vegetation and take approximately a day to develop into fry. The larvae are free swimming in two days and stay in the floodplains for only a short time. When juveniles reach about 5 to 7 cm they migrate back through rivers to slower water where they spend the majority of their lives. (Christensen, 1992; Pethiyagoda, 1991)

Kissing gourami spawn once a year. Females initiate matings and only mate with one male per spawn. They do not seem to show any mate choice and do not keep the same mate for future spawnings. (Christensen, 1992; Pethiyagoda, 1991)

Helostoma temminkii are oviparous and dioecious and demonstrate external fertilization. They spawn once a year at the beginning of the rainy season. Adults migrate through rivers into shallow lakes or flooded forests to spawn. A female initiates mating and she and the male fish turn almost upside down before simultaneously releasing the eggs and sperm. Females release on average 1000 eggs. Eggs are usually small compared to other freshwater species and have an oil droplet to increase buoyancy. Fertilized eggs float to the surface and usually attach to floating vegetation. The eggs develop into fry that become free swimming after two days. Kissing gourami reach sexual maturity at three to five years of age. (Christensen, 1992; Davis, 1959; Pethiyagoda, 1991)

Besides the investment of energy that goes into spawning, Helostoma temminkii do not invest in their offspring. Unlike closely related species, kissing gourami do not build nests or care for their young. (Riehl and Baensch, 1991; Sterba, 1983)

In captivity and in the wild the average lifespan is 5 to 7 years, but they can live much longer. (Axelrod, et al., 1971; Sterba, 1983)

Helostoma temminkii is able to derive oxygen from water and air. It is able to get oxygen out of the air with paired suprabranchial chambers that have a bony element inside covered with a highly vascularized layer of tissue called the labyrinth apparatus. It gulps air at the surface and holds it in these chambers. It also expels air from its mouth while it is above water. Air breathing allows H. temminkii to survive in very oxygen-poor water.

The characteristic “kissing” behavior that gives the fish its name occurs frequently, especially during feeding and also sometimes during courtship and combat. It is caused by contraction of the epaxial muscles and the most commonly accepted explanation for the behavior is that it is a ritualized form of aggression. In general, kissing gourami are a relatively non-aggressive species. (Liem, 1967; Riehl and Baensch, 1991; Sakurai, et al., 1993; Skobe, et al., 1970)

There is no information on the home range of H. temminkii. (Randle and Chapman, 2005)

Kissing gourami have very acute hearing due to a suprabranchial air-breathing chamber located close to the inner ear. The air bubbles in the suprabranchial chamber modulate and enhance their ability to hear. Kissing gourami frequently emit sounds that are associated with social behavior and this sound is achieved by grinding their pharyngeal teeth. (Ladich and Yan, 1998; Sakai, et al., 1995; Yan, 1998)

Kissing gourami are omnivorous. They feed on phytoplankton, zooplankton, and aquatic insects, supplemented by plant material. They are considered to be the most highly specialized freshwater filter-feeder of southeast Asia with very intricate gill rakers. (Liem, 1967; Rainboth, 1996; Roberts, 1989)

Kissing gourami are eaten by humans in some areas of Southeast Asia. (Edwards, et al., 1997; Rainboth, 1996)

Helostoma temminkii can be host to parasitic algal species that live under their skin and look like color spots. Fish with the algal growth are somewhat emaciated and generally less healthy than fish without the algae. The algae possibly receive some of the requirements for photosynthesis and protein synthesis from the fishes’ bodies. (Nigrelli, et al., 1958; Nigrelli, et al., 1958)

Kissing gourami are very popular aquarium fish, and are collected in their native habitat to sell and are also bred and sold out of Florida. They are popular fish in the aquarium trade in part because of their high tolerance to crowding. They are also an important food fish in Southeast Asia and are desirable because they can be kept alive for prolonged periods in markets. (Edwards, et al., 1997; Ng and Tan, 1997; Rainboth, 1996)

There are no known adverse affects of Helostoma temminkii on humans. Although there are many theoretically adverse affects that could be associated with their accidental release outside of their natural habitat, there have not been any well-documented cases. (Courtenay and Stauffer, 1991)

Kissing gourami are not on the IUCN Red List, and although they are heavily fished in their natural habitat, they are still one of the most common fish in the area. (Christensen, 1992)