Aethinosis

Aethinosis or ethinosis is a disease of the hives caused by the nitidulid beetle Aethina tumida, whose larvae feed on honey, pollen and eggs, producing galleries in the combs and destroying them. Up to 30,000 larvae can be found per hive. Feces deposited in honey do not determine fermentation. The colony weakens until it collapses. The European races of Apis mellifera do not know how to defend themselves, the African ones go so far as to coat the insects with propolis.

Small hive beetle Aethina tumida, Murray (1867). It is a beetle of the Order Coleoptera, of the Family Nitidulidae, a group characterized by its affinity to fermenting plant products. In the case of Aethina tumida, the affinity to fermenting plant products is associated with bee colonies, such as honey and pollen, but can be reproduced in fermented fruits (there are numerous species). It is thought to have been transported to North America in contaminated fruit from southern Africa, where they originate. The Little Hive Beetle. The adult Little Beetle is approximately 3/16 to 1/4 inch long and oval with two very characteristic antennae ending in a club shape. It is a strong flyer, it enters the interior of the hives flying through the spout, it moves quickly. The larva looks superficially similar to the wax moth larva.

Etiology

The rapid expansion of Aethina tumida, a beetle that parasitizes apiaries, originally from southern Africa, found in the United States in 1998, in 2000 in Egypt and recently in Canada, Australia (2002) and Nicaragua 2014 and the news that has already appeared in specialized magazines suggest that it will be a pest that will spread worldwide like Varroa.

Originally from Africa, in the Sub-Saharan region, it originally affected the subspecies Apis mellifera scutellata and Apis mellifera capensis. In the adult state it is five millimeters in length and its color varies from dark brown to black.

In South Africa it is considered a lesser evil, which mainly attacks weak colonies and stored frames, and its treatment is generally not necessary.

Epizootiology

The spread of the disease is carried out by the flight of the beetle and is favored by transhumance. The eggs can also be dispersed attached to the body of the bees. It has been proven that it can live up to five days without eating or drinking, so care must be taken with replacement material.

Diagnosis

Clinical. The adult and larval forms are easy to see in the combs and at the bottom of the attacked hive. When an affected hive is opened, a strong smell of fermented honey is detected. They have two centimeters at their maximum stay.

Differential. The larvae of Aethina tumida can be confused with those of Gallaria mellonella.

Treatment

In the United States, Coumaphos (organophosphate) is used in the form of strips placed at the bottom of the hive on corrugated cardboard, and Permethrins (pyrethroid). They have been found in hives with strips of Apistan, so it seems that this has no effect on the beetle.

Damage caused

The larvae feed on honey, pollen, and eggs, producing galleries in the combs, destroying them. Up to 30,000 larvae were found per hive. Feces deposited in honey do not determine fermentation. The colony weakens until it collapses. The European races of Apis mellifera do not know how to defend themselves, the African ones go so far as to coat the insects with propolis.

Control of apiaries

• Remove the roof, place it on the floor turned, support the melarium on it and leave it for about a minute, the parasite that refuses to light, will seek refuge in the background, lift the melarium and quickly observe the inner surface of the ceiling to discover the eventual presence of Aehtina.
• If we do not observe parasites in the melarium, continue the inspection of the breeding chamber, removing the boxes of the breeding nest one by one and observing the surface to discover the presence of adults or larvar forms in the deoperculated cells.
• Once the pictures are removed, we examine the floor of the hive by paying particular attention to the angles, where the parasite tends to take refuge to refuse the light.
• If the floor has a removable drawer, observe the contents to individualize any waste of the parasite in larvae forms.
• In the event that the presence of parasites (or small coleopters or presumed larvae forms) is discovered, once captured (with tweezers or fingers) insert them into a testet or in a jar, then arriving at a laboratory where their analysis is carried out.

Honey extraction rooms

The Small Beetle of the hive is present in the honey extraction room because they are transported with the supers to be harvested; Any beetle eggs or larvae can develop rapidly, resulting in thousands of larvae crawling on the extraction room floors. Hot water, soap and bleach will kill most of them, but prevention is better than control. It is a good idea to bring honey supers inside the extraction room and process it as quickly as possible. The caps should also be processed as quickly as possible to obtain wax.