Tropilaelaps
- What is it?
- Parasitic mite of Laelapidae family.
- Has four sub-species two attack Apis mellifera
- T. mercedesae - found throughout Asia
- T. clareae -only found in Phillipines - so far.
- Sub species can only be distinguished in the laboratory.
- Characteristics
- 8 legged arachnid
- 2 antennae
- Elongated body 1.5 mm long by 0.5mm wide
- Varroa is 1.6mm long and 1.1mm wide
- Light reddish brown in colour
- Moves rapidly along cell tops
- Risk to the UK bee population
- Nearest established population is Iran and Kazakhstan
- Could be imported with imported queens and attendants.
- Cannot survive on their own or on dead bees
- Can survive on larvae and newly emerged adult bees.
- Greatest risk is from illegally imported bees.
- Life cycle
- Adult mite enters the cell of the larva before it is capped
- There is a preference for drone larvae but not as great as Varroa's preference.
- Waits 48 hours after it is capped.
- Lays 3 to 4 eggs a day as long as cell is capped
- Worker cell will be capped for 11 days.
- Drone cell will be capped for 14 days.
- Eggs will hatch after 12 hours.
- Young will mature to adult after 6 days.
- When the adult bee emerges then all will emerge
- A single cell can hold 14 adults and 10 nymphs.
- There can be more Tropilaelaps in a cell than the larva can cope with.
- If that happens the larva and parasites all perish
- Varroa will self limit numbers and slow down their metabolic rate if there are too many.
- Adult Tropilaelaps will spend 1 or 2 days in
phoretic stage Hitching a ride on the adult beee..
- Adult Varroa spend 5 to 11 days in the phoretic stage.
- Adult varroa need a protein only found in adult bees.
- The newly emerged adult Tropilaelaps need to lay within 2 days if already pregnant.
- Harmful effects
- Increased brood mortalilty and deformity
- Tropilaelaps will chew multiple holes in the larva.
- Varroa pierce the larva once and always feed from that spot - they latch on.
- Tropilaelaps may be a vector for Deformed Wing virus and Acute Bee Paralysis
- Suggested that they are also a vector for Black Queen Cell Virus
- Can overwhelm the colony and lead to its death.
- If unchecked Tropilaelaps can double its popuation in 10 days in a hive
- If unchecked Varroa takes 30 days to double its population in a hive.
- Tropilaelaps only spend 1 or 2 days in phoretic stage
- Rest of the time is available for breeding
- Varroa will spend 7 days in phoretic stage so less time for breeding.
- Detection
- Not easy to see as they are very small and very fast.
- Look for symptoms of mite infestation and work backwards from there.
- Chewed cell caps indicate workers trying to remove sick or dead larvae.
- Prevention
- Do not import bees from anywhere - local is best.
- Practice good apiary hygiene.
- This is a notifiable disease
- You must notify your local bee inspector if you suspect Tropilaelaps
- Cure
- As the mite spends less time in the phoretic stage it is not easy to kill.
- Most of its life is in a capped cell where miticides cannot get to it.
- 85% formic acid will kill an infestation. Place it in the hive to vapourise.
- Remove the bees from the brood and destroy the brood - a shook swarm approach.
- Further reading
- NBU booklet
- You Tube Videos
