iNaturalist Meta-Survey of Thread-Waisted Wasps of Southeast United States and Northeast Florida
By Dave Hebert
UF/IFAS Extension Nassau County
Introduction
Entomological tribe Ammophilini contains several genera of thread-waisted wasps. These beneficial wasps are native to North America and often found in the eastern portion of the United States, especially in the southeast. They can be mistaken for damselflies while in graceful flight, or when resting on stems, utilizing their mandibles for support. This article highlights and summarizes the data from iNaturalist, showing researchers and naturalists how many of each species are in which regions of the United States, and which plants are attractive to a Ammophila pictipennis.
Biology
Thread-waisted wasps are slender, have elongated bodies, and are parasitoids of lepidopterous larvae. Thread-waisted wasps parasitize, or implant their eggs into a caterpillar or moth larvae which produces a new generation of offspring. They can be observed digging in bare soil to form a new nest. They visit a variety of flowers and plants, including white beggarticks (Bidens alba).
Figure 1. Ammophila pictipennis wasp drinks nectar from white beggarticks. Photo: iNaturalist user kcthetc1.
Tribe Ammophilini Survey
There are many different species in the tribe Ammophilini. East of the Mississippi River, 13 different species have been reported on iNaturalist.org with a “research-grade” notation. South of the Tennessee border, which includes parts of Louisiana, Mississippi, Alabama, Florida, Georgia, and South Carolina, 4 research-grade species have been reported.
Figure 2. Survey area showing 351 verifiable observations of tribe Ammophilini Source and Photo: iNaturalist.org
A custom boundary was applied to the “explore” feature for about 12,000 square miles in Northeast Florida to see which genera in the Ammophilini tribe have been reported. The boundary isolated 351 verifiable observations, but when filtered again for “Research-Grade”, there were only 172 in the same area, composed of just 3 species: 1) Common-thread waisted wasp (Eremnophila aureonotata) – 66 observations, gold-marked thread-waisted wasp (Ammophila procera) – 45 observations A. pictipennis – 59 observations. These wasps were all photographed either on a plant, bare soil/gravel/debris, or in the act of parasitizing a caterpillar or moth larvae.
A. pictipennis Survey
Ammophila pictipennis was observed on a variety of plants; however, some plants seem to be preferred. A custom boundary was applied to the “explore” feature for “Ammophila pictipennis”, generating 59 research-grade observations in an area of about 12,000 square miles of Northeast Florida. The wasp was observed resting, landing, and/or drinking nectar from 32 different plant species with the following protocol.
A research grade observation of A. pictipennis was opened. Next, the photograph was modified using an artificial intelligence “erase” tool to remove the wasp. With only the plant in the photo, the plant was either identified by memory or by using Seek by iNaturalist – pointing the camera at the computer screen to give a suggestion. In that case, the suggestion was cross-referenced to confirm a match. Unfortunately, several photos proved unable to extrapolate a clear picture and/or identification of the plant, however; many photos were successful. In Northeast Florida, based on iNaturalist.org, since April 2016, A. picipennis was observed on St. Augustine grass (Stenotaphrum secundatum) 7 times, white beggarticks (Bidens alba) 5 times, and southern beeblossom (Oenothera simulans) 4 times.
Conclusion
Meta-data surveys provide new insight into environmental research and helps paint a picture of species distribution and behavior of insects, although it is limited. iNaturalist is a collection of human inputs, which can be error prone. Research-grade observations must have a date, location with GPS inputs, photo or sound, identifiable at a species level, and have at least two users agreed, with no major disagreements. Verifiable observations must have a date, location, and a photo or sound. iNaturalist is an independent 501(c)(3) nonprofit organization.
