Ophiocordyceps robertsii, known in New Zealand as vegetable caterpillar (Māori: āwhato or āwheto[1]) is an entomopathogenic fungus belonging to the order Hypocreales (Ascomycota) in the family Ophiocordycipitaceae.[2] It invades the caterpillars of leaf-litter dwelling moths and turns them into fungal mummies, sending up a fruiting spike above the forest floor to shed its spores. Caterpillars eat the spores whilst feeding on leaf litter to complete the fungal life cycle. Evidence of this fungus can be seen when small brown stems push through the forest floor: underneath will be the dried remains of the host caterpillar.[3] This species was first thought by Europeans to be a worm or caterpillar that burrowed from the top of a tree to the roots, where it exited and then grew a shoot of the plant out of its head.[4] It was the first fungus provided with a binomial name from New Zealand.[5]
| Ophiocordyceps robertsii | |
|---|---|
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| Ophiocordyceps robertsii in the collection of the Whanganui Regional Museum | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Sordariomycetes |
| Order: | Hypocreales |
| Family: | Ophiocordycipitaceae |
| Genus: | Ophiocordyceps |
| Species: | O. robertsii
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| Binomial name | |
| Ophiocordyceps robertsii (Hook.) G.H. Sung, J.M. Sung, Hywel-Jones & Spatafora (2007)
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| Synonyms | |
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Cordyceps robertsii (Hook.) Berk. 1855 | |
Uses
editThe parasitised caterpillar has been used by Māori as a food or to create an ink called ngārahu for traditional tā moko tattoos. The charred caterpillars were mixed with tree sap to make an almost black ink.[6] Scientists suggest that the fungus produces antiseptic chemicals that can prevent infection. In the early 20th century, mummified caterpillars were sold to tourists as a curio.[3]
Genomics
editOphiocordyceps robertsii has a genome that is relatively large for species in the Ophiocordycipitaceae family, estimated at between of 95-103 million base pairs.[7] This size is comparable to that of the related species Ophiocordyceps sinensis. Analysis of the genome sequence revealed much of the size is due to DNA that is repetitive. The analysis also identified the mating-type locus, supporting a heterothallic lifecycle for the species, in which strains of the MAT1-1 and MAT1-2 types are required for mating.
References
edit- ^ Crowe A (2002). Which New Zealand Insect?. Auckland: Penguin. p. 19. ISBN 0141006366.
- ^ Sung GH, Hywel-Jones NL, Sung JM, Luangsa-Ard JJ, Shrestha B, Spatafora JW (2007). "Phylogenetic classification of Cordyceps and the clavicipitaceous fungi". Studies in Mycology. 57: 5–59. doi:10.3114/sim.2007.57.01. PMC 2104736. PMID 18490993.
- ^ a b "Vegetable Caterpillar". Science Learning Hub. Retrieved 21 July 2017.
- ^ Williams JB (1844). "The New Zealand Journal, 1842–1844 of John B. Williams Of Salem, Massachusetts". The New Zealand Journal 1842–44: 108.
- ^ Relph D. "Caterpillar Killer". New Zealand Geographic. Kowhai Media. Retrieved 21 July 2017.
- ^ Lehnebach, Carlos A.; Regnault, Claire; Rice, Rebecca; Awa, Isaac Te; Yates, Rachel A. (1 November 2023). Flora: Celebrating our Botanical World. Te Papa Press. ISBN 978-1-9911509-1-2.
- ^ Xu M, Ashley NA, Vaghefi N, Wilkinson I, Idnurm A (2 May 2023). "Isolation of strains and their genome sequencing to analyze the mating system of Ophiocordyceps robertsii". PLOS ONE. 18 (5): e0284978. doi:10.1371/journal.pone.0284978. PMC 10153710. PMID 37130139.
External links
edit- Ophiocordyceps robertsii discussed in RNZ Critter of the Week, 21 July 2017