In addition to being rare, it is also the most difficult to locate. Due to its small size, only 5-10 mm, it is only found in tropical regions. In 1919, the first was discovered in Sri Lanka. The second time was discovered in Hawaii, United States, and rediscovered in Thailand in 2006 by Dr. Ratchet Cheoklin of the National Biobank of Thailand. This study is a collaboration between The National Bank of Thailand, the University of Florida, and Dr. Nattapon Kraisitudomsuk, a researcher.
Before morphology and molecular biology caused a name change, the primary identity was determined. Each of the four samples was identified as distinct. The inner wall tissue layer, also known as the peridiole cortex, is a thickly walled, net-like structure. Each of the two types of spore-producing cells found in the next identity contained two or four spores. This two sections presents the new genus designation as a "Retiperidiolia".
In 2006, two specimens from Thailand were discovered in Thale Ban National Park, Satun Province. Two samples, which represented fifty percent of those discovered worldwide, were collected. The discovery is long overdue, and a re-analysis of the discovered global samples reveals new information. The Phylogenetic Tree results validate morphological data as an evolutionary branch of the genus Mycocaria. The inner wall structure of the peridiole is the most noticeable distinction between these two genera.
The study was published in the volume 21 issue 56 of the journal Mycological Progress (2022). Thailand-dried samples were chosen as the epitype and stored at the Thailand-based BIOTEC Bangkok Herbarium & Fungarium (BBH). The holotype specimens were collected in Sri Lanka's Botanical Garden.
You can download the poster from the Open Education Resources Library (OER), which is part of the project "Online communication system project for distant learning" in honor of Her Royal Highness Princess Maha Chakri Sirindhorn on the occasion of her 5th Cycle Birthday Anniversary on April 2, 2015.
Image from "Bird Nest Fungi, the "new genus of the world", which is licensed under Creative Commons, but commercial use and attribution are not permitted under 3.0 Thailand.
Kraisitudomsook, N., Choeyklin, R., Boonpratuang, T. et al. Hidden in the tropics: Retiperidiolia gen. nov., a new genus of bird’s nest fungi (Nidulariaceae), and a systematic study of the genus Mycocalia. Mycol Progress21, 56 (2022). DOI Link