Consider the following:
- 1.Carabid beetles
- 2.Centipedes
- 3.Flies
- 4.Termites
- 5.Wasps
Parasitoid species are found in how many of the above kind of organisms?
Answer & explanation
Answer: (b) Only three
A parasitoid is an insect whose larva lives on or inside a single host and eventually kills it. Almost all parasitoids are wasps and flies, with a smaller number of beetles, including some carabid (ground) beetles. Centipedes are free-living predators and termites are social decomposers, so only three groups qualify.
- ✓ 1. Some carabid beetles are parasitoids: for example, the larvae of Lebia grandis develop on and kill the pupae of the Colorado potato beetle.
- ✗ 2. Centipedes are active predators that kill prey with venomous claws; they do not develop inside a host.
- ✓ 3. Many flies are parasitoids — tachinid and conopid flies, for example, grow inside other insects and kill them.
- ✗ 4. Termites are social insects that feed on wood and plant matter; none lives as a parasitoid.
- ✓ 5. Parasitic wasps are the largest parasitoid group: they lay eggs inside other insects and the host dies, which is why they are used in biological pest control.
Remember · Parasitoids kill their host (unlike true parasites). Main groups: wasps (Hymenoptera), flies (Diptera), some beetles. Used widely for biological pest control.
Sources
- FAO, Vegetable IPM Regional Training on Biological Control (Thailand DoAE): parasitoids ↗ “Parasitoids are parasitic insects whose larvae feed on the living tissues of an arthropod host. Most are wasps (Hymenoptera), but a few are flies (Diptera).”
- USDA Agricultural Research Service (Weber, Saska and Chaboo), Carabid Beetles (Coleoptera: Carabidae) as Parasitoids ↗ “Several genera of carabid beetles are ectoparasitoids as larvae. The parasitoid habit is uncommon in beetles; only eleven beetle families include parasitoid species … Lebia species number over 450 and the genus is cosmopolitan, with 47 in North America. Adults typically seek prey in plant canopies, and all known larvae are ectoparasitoids of chrysomelid beetle pupae”
- USDA Agricultural Research Service, AgResearch Magazine: Identifying Tiny Wasps ↗ “And correct identification is critical, as these parasitic wasps lay their eggs inside other insect species, killing the host insect in the process. As a result, these wasps are used extensively, worldwide, to control pest insect populations in agriculture.”
Question and answer: UPSC's official GS Paper I (2024, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·