20 November 2023

Finally another Wayne County record

It's been 10 years since we published our Wayne County, Michigan checklist, and this past decade it has stood at 90 species supported by voucher specimens. We moved out of the county 11 years ago, and have concentrated our efforts elsewhere. We have visited some of our old haunts more recently, but this very urban county has seen still more development, further lessening the opportunity for discovering new species, or even seeing many previously recorded ones.

This is not to say that vouchers have not been added to the Michigan database we are working on.  As we explained in our Plains Emerald post, we've been working with various watershed groups to identify the odonate nymphs they collect during their water quality surveys. We've incorporated these identifications into our data, and thus have acquired dozens of data points for nymphs in Wayne County, primarily from material from Friends of the Rouge and the Huron River Watershed Council

We've also been looking through the collections, both of adults and nymphs/exuviae, at the University of Michigan. We've been aware of a record of a nymph of Springtime Darner, Basiaeschna janata, for the county, but we've never been able to locate it. It is a species that was on our "hypothetical" list, because we have a sight record from Livonia in 2006. 

Looking for particular immature specimens among thousands of vials in hundreds of racks.
We finally came across the vial with a late instar nymph last week, stuck in a box of miscellaneous stuff rather than filed in the racks with the rest of the Aeshnidae.

The long-lost vial.

We confirmed the nymph is, indeed, Springtime Darner. Unfortunately, there is no location on the tag, and we have no information or other data from this collector, although we've searched all taxa across many collections in data aggregators. We suspect the tag in the vial is not the original, as it looks to be written by Ethan Bright, who did the initial identification. Since this isn't a particularly rare or unusual species and expected in the county, it is now tallied as the 91st on the Wayne County checklist.

This Springtime Darner was netted in Livingston County in 2018.

11 November 2023

An update on the state record for Argia translata

In a previous blog post, we discussed the addition of Dusky Dancer (Argia translata) to the Michigan list. Our first "discovery" of this species for the state was two adult specimens cataloged in the University of Michigan Museum of Zoology (UMMZ) collection: a female collected on 25 June 1957 and a male collected on 7 July 1957, both by Rodger Mitchell at the University's E.S. George Reserve in Livingston County. 

We looked for these specimens at UMMZ, but couldn't locate them. Thus, we went in search of this species. On 10 September 2019, we collected a male on the Huron River at Bandemer Park, Ann Arbor, Washtenaw County. 

Male Dusky Dancer, Huron River, 10 Sep 2019.

We have also collected this species elsewhere on the Huron River in Washtenaw County, as well as the Saline River in Monroe County.

Recently, we've been working much more in the UMMZ collection. We decided to try looking for the 1957 Livingston County vouchers again. An additional motivating factor was that we have also been working with a lot of data from the E.S. George Reserve, and there are many ponds but no creeks or rivers there. Consequently, there are only a few Argia specimens, and they are all Variable (Violet) Dancer, Argia fumipennis, a species often found away from water.

In the drawer of Argia translata specimens, we found a triangle for a Variable Dancer whose data and catalog number matched one of our missing Dusky Dancer specimens.

The data sheet for the missing male "Argia translata" along with the paper triangle and matching catalog number. The triangle correctly labels it as Argia fumipennis violacea.

The damselfly in the triangle was indeed a male Variable Dancer. Although it was fragile and lacked color, you can see in the photo below that the abdomen was largely pale where it is largely dark in Dusky Dancer, and the pattern on the final segments also does not match.

The correctly identified, incorrectly cataloged specimen.

Last abdominal segments of a male Argia translata.

We did not locate the other missing voucher in the drawer of Argia translata specimens; once we found this one we only skimmed through the rest. We suspect that someone may have been entering data for Argia translata and, because this correctly labeled triangle was in the wrong drawer, just entered it as A. translata. This would be an unusual species for this location, and we are pretty confident the other missing item is not A. translata.

Therefore, the male we collected in 2019 is the first state record for this species.

11 July 2023

Plains Emerald -- new for Michigan

Update: Our article on this new additions has been published in Argia, a publication of the Dragonfly Society of the Americas. You can read the paper here.

Plains Emerald (Somatochlora ensigera) is found primarily west of the Mississippi River. Eastern records come from three U.S. states (Wisconsin, Indiana, and Ohio) and one Canadian province (Ontario, although there are multiple records from western Ontario and provinces further west). There are no previous Michigan records.

As part of our efforts to document the distribution of Michigan Odonata, the Michigan Department of Environment, Great Lakes, and Energy (EGLE; formerly the Department of Environmental Quality) has been sending us nymphs collected during their watershed surveys. These surveys only identify aquatic macroinvertebrates to family, so Darrin has been spending winter days identifying as many to species as possible, and we've garnered many new county-level records form these efforts. 

Several nymphs collected by EGLE's Elizabeth Stieber in August 2022 in southern Menominee County in the western Upper Peninsula were highly suggestive of Plains Emerald. Many traits, particularly measurements and ratios, were difficult to discern on these early to mid-instar individuals, so we didn't want to make a definitive call on ID. 

The nymphs went next to Anthony Cognato and Jordy Hernandez at Michigan State University for DNA sequencing as part of a larger project on Somatochlora phylogeny. Two of the nymphs were a match for Plains Emerald, based on reference material from Minnesota. DNA could not be sequenced from a third nymph. 

The two matching nymphs were from the Little River southeast of the town of Wallace, ~8 km east of the Wisconsin border. The third nymph was from Kelley Creek, northwest of the town of Birch Creek and ~5.5 km east of the Wisconsin border. The closest record of Plains Emerald to these Michigan locations is from 1988 in neighboring Marinette County, Wisconsin.

Collection site of two Plains Emerald nymphs on the Little River, Menominee County, Michigan
Photo by Elizabeth Stieber.

This brings the Michigan checklist to 170 species based on voucher specimens.

Further reading:

Beckemeyer, R. 1998. A brief history of the Plains Emerald - Somatochlora ensigera. Argia 10:17–20.

DuBois, R. B., and K. J. Tennessen. 2008. Nymphal habitat of Somatochlora ensigera Martin (Plains Emerald). Argia 20:9–11.

Williamson, E. B. 1912. The known Indiana Somatochloras (Odonata). Entomological News 23:152–155.

Williamson, E. B. 1922. Indiana Somatochloras again (Odonata, Libellulidae). Entomological News 33:200–207.

21 March 2023

Michigan's new threatened and endangered species list

Every few years, the state of Michigan tasks various committees of experts with reviewing threatened and endangered species, as required by law. The past two cycles one of us (Julie Craves, a.k.a. Nannothemis) has been a member of the Insect Technical Advisory Committee. The committee works to form recommendations on elevations, downgrades, additions, and subtractions to the list, which then goes through a review process that includes internal review and public comment before being signed into law.

There were multiple changes made to the list of Odonata in the recommendations submitted in 2014-2015, but they were not acted upon by the state for various (mostly political) reasons. The Whitmer administration called for an update and the Committee once again revised the list, and submitted changes in September 2019. After delays related to Covid, the state list was finalized and signed into law on 20 March 2023. The entire state threatened and endangered species list including all species can be viewed here.

The Odonata list is below. On the Michigan Odonata Survey rare species webpage, we have other conservation-oriented lists of Odonata in the state.

Hine’s Emerald – Somatochlora hineana Williamson no change
Russet-tipped Clubtail – Stylurus plagiatus (Selys) – elevated from special concern
Gray Petaltail – Tachopteryx thoreyi (Hagen in Selys) – elevated from threatened

Tiger Spiketail – Cordulegaster erronea Hagen in Selys- elevated from special concern
Alleghany River Cruiser — Macromia alleghaniensis Williamson – new to list
Pygmy Snaketail – Ophiogomphus howei Bromley – no change
Elusive Clubtail – Stylurus notatus (Rambur) – elevated from special concern

Special concern (no legal protection)
Extra-striped Snaketail – Ophiogomphus anomalus Harvey
Incurvate Emerald – Somatochlora incurvata Walker
Riverine Clubtail – Stylurus amnicola Walsh
Laura’s Clubtail – Stylurus laurae Williamson

Removed from special concern
Smoky Rubyspot – Hetaerina titia (Drury)
Splendid Clubtail – Gomphurus lineatifrons (Calvert)
Rapids Clubtail – Phanogomphus quadricolor (Walsh)
Ebony Boghaunter – Williamsonia fletcheri Williamson
Ringed Boghaunter – Williamsonia lintneri (Hagen in Selys)