Insect (Coleoptera) Biodiversity Across Forest Canopy and Understorey in SE-Asia BIFA5_026

Study Extent

The study was conducted in the tropical forests of Mo Singto area at Khao Yai National Park (14N, 101E) and Klong Naka Wildlife Sanctuary (9N, 99E). Sampling took place in June and December 2019 at Khao Yai and March and September 2020 at Klong Naka.

Sampling

At Mo Singto, we conducted insect sampling within the 30-ha monitoring plot designed to study vegetation and vertebrate (mainly gibbons) communities (Brockelman et al. 2011). Similarly, we used the 20-ha monitoring plot established in 2019 at Klong Naka designed to study vegetation community dynamics. These monitoring plots are subdivided into 20 m x 20 m subplots. Within each monitoring plot, we set a 300 x 300 m square area and established nine sampling points (3 x 3 grid arrangements). We used nine of the sub-plots where these nine sampling points were located. At each of the nine 20 m x 20 m sub-plots, we found suitable trees where traps can be suspended at the canopy and understory strata. Understory traps were suspended at 2 m above the ground whereas canopy traps were suspended immediately below the canopy foliage. The height of the canopy traps changed depending on the tree height (the information on the height of the traps is provided in the sampling event data). We selected a tree whose top foliage received direct insolation, but we did not select midstory or emergent trees. The ropes to suspend the canopy traps were hung over the tree branches by first shooting the throw line (2 mm diameter, BARHAR, Dongguan, Guangdong, China) using an arborist slingshot (Big Shot Line Launcher, WesSpur Tree Equipment, Bellingham, WA, USA). The throw line was replaced with a nylon rope (approx. 8-10 mm diameters) to which the trap was attached and hoisted to the canopy stratum. A nylon rope was also used to suspend the traps at the understory. The SLAM traps (the Sea, Land, and Air Malaise traps) were used to capture flying insects in the canopy and understorey strata. The mechanisms of the SLAM traps are essentially the same as conventionally used Townes-type Malaise traps: the traps intercept the flying insects with the black screen and insects flying up the screen are eventually collected at the top where the opening leads to a plastic bottle with ethanol (Achterberg, 2009). The SLAM traps, however, can be suspended in mid-air, enabling the collection of flying insects in the canopy stratum. We manufactured the SLAM traps following those produced by Bugdorm, MegaView Science, Taiwan, China (https://shop.bugdorm.com/slam-trap-large-p-111.html). The SLAM trap consists of the top opening (that leads to the collection jar) that captures insects that fly up along the screen and, in addition, bottom cloth funnels (with collection jar at the end) that capture the insects that drop as they hit the intercepting screen. Both top and bottom collection jars contained 500 ml of 95% ethanol as a killing and preserving agent. To prevent the bottom collection jars from being filled with rain water, we added a white umbrella-like structure (approximately 2 m diameter) to cover the SLAM traps. At each sampling event, we run the traps for 10 consecutive days. After the samples were taken, we replaced the old ethanol with 99% ethanol. All beetle specimens were taken, and representative specimens were dry-mounted for identification. We used Nakane et al. (1975) to identify the specimens into family or subfamily and then morphospecies with assistance from the local taxonomists. All wet and dry specimens were stored at the Mahidol University Museum of Natural History. Brockelman, W. Y., Nathalang, A. and Gale, G. A. 2011. The Mo Singto forest dynamic plot, Khao Yai National Park, Thailand. Natural History Bulletin of the Siam Society. 57: 35-55. Achterberg, K. V. 2009. Can Townes-type Malaise traps be improved? Some recent developments. Entomologische Berichten: 69: 129-135. Nakane, T., Ohbayashi, K., Nomura, S. and Kurosawa, Y. 1975. Iconographia Insectorum Japonicorum Colore naturali edita Vomumen II (Coleoptera). Hokuryukan, Tokyo, Japan.

Quality Control

The field surveys were mainly conducted by the local assistants and students, but supervisors visited both Mo Singto and Klong Naka to check the sampling areas and ensure that the fieldwork followed our sampling protocols described above. Taxonomic identification has been conducted by the students and they collaborated with local taxonomists to check their family-level identification.

Method steps

1. 1. At each of the nine 20 m x 20 m sub-plots, we found suitable trees where traps can be suspended at the canopy and understory strata. Understory traps were suspended at 2 m above the ground whereas canopy traps were suspended immediately below the canopy foliage. The height of the canopy traps changed depending on the tree height (the information on the height of the traps is provided in the sampling event data). 2. We selected a tree whose top foliage received direct insolation, but we did not select midstory or emergent trees. The ropes to suspend the canopy traps were hung over the tree branches by first shooting the throw line (2 mm diameter, BARHAR, Dongguan, Guangdong, China) using an arborist slingshot (Big Shot Line Launcher, WesSpur Tree Equipment, Bellingham, WA, USA). The throw line was replaced with a nylon rope (approx. 8-10 mm diameters) to which the trap was attached and hoisted to the canopy stratum. A nylon rope was also used to suspend the traps at the understory. 3. The SLAM trap consists of the top opening (that leads to the collection jar) that captures insects that fly up along the screen and, in addition, bottom cloth funnels (with collection jar at the end) that capture the insects that drop as they hit the intercepting screen. Both top and bottom collection jars contained 500 ml of 95% ethanol as a killing and preserving agent. To prevent the bottom collection jars from being filled with rain water, we added a white umbrella-like structure (approximately 2 m diameter) to cover the SLAM traps.
   4. At each sampling event, we run the traps for 10 consecutive days. The samples were then taken to a bottle, and the liquid was replaced with 99% ethanol. 5. All beetle specimens were taken, and representative specimens were dry-mounted for identification. We used Nakane et al. (1975) to identify the specimens into family or subfamily and then morphospecies with assistance from the local taxonomists. All wet and dry specimens were stored at the Mahidol University Museum of Natural History.

N/A

1. Coleoptera
   rank: order
2. Ptilodactylidae
   rank: family
3. Arthropoda
   rank: phylum
4. Insecta
   rank: class
5. Carabidae
   rank: family
6. Mycetophagidae
   rank: family
7. Lophocateridae
   rank: family
8. Aderidae
   rank: family
9. Ptinidae
   rank: family
10. Curculionidae
    rank: family
11. Clambidae
    rank: family
12. Anthicidae
    rank: family
13. Chrysomelidae
    rank: family
14. Anthribidae
    rank: family
15. Cerambycidae
    rank: family
16. Histeridae
    rank: family
17. Corylophidae
    rank: family
18. Staphylinidae
    rank: family
19. Animalia
    rank: kingdom
20. Eucnemidae
    rank: family
21. Phalacridae
    rank: family

Mo Singto area at Khao Yai National Park (14N, 101E) and Klong Naka Wildlife Sanctuary (9N, 99E). In each location, a total of nine sampling points (300 x 300 m grid) were set within the forest dynamic plots (ForestGEO plots).