Calvert County (MD) Dragonflies and Damselflies: Part Ten – Pennant Dragonflies of the Family Libellulidae

Family: Libellulidae (Pennants)

Due to the large number of species present for this family, I will be breaking down the family into smaller segments starting with the Pennant dragonflies. First some comments about the Family Libellulidae. For our area, this is certainly the dominant group of dragonflies in terms of the number of species and the overall observations in iNaturalist. An examination of the dragonfly observations for each of the three southern Maryland counties reveals that 88% or greater of the total number of observations for all dragonflies are comprised of Libellulidae family dragonflies. For Calvert, Charles, and St. Marys Counties, the number of Libellulidae family vs. total observations are 305/328, 147/166, and 44/50, respectively.

For myself, the Libellulidae family is the first family of dragonflies in which I have made observational contributions to the Calvert County iNaturalist database. To date, I have submitted a total of 116 observations for 17 different species. Of the Calvert Pennant dragonflies, nine of the eleven observations for the Halloween Pennant are mine and also one of the five observations for the Four-spotted Pennant.

Of the six Pennant species listed below for southern Maryland from Richard Orr’s database, four of the six can be found in all three southern Maryland counties. This includes two species on the S3 Watch List of the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”. The S2 State Rare Double-ringed Pennant is only known from Charles County.

Listed below are the Pennant species within the Libellulidae family that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of February, 2020). As was done with the previous family, I have included with most species a note extracted from the book “Natural History of DelMarVa Dragonflies and Damselflies” by Hal White (reference 1). Of particular relevance for Calvert County, I have also included information on the four species of this group that were observed at the Cove Point LNG Property and reported in “2011-2012 Survey of the Dragonflies and Damseflies (Odonata) of the Cove Point LNG Property (Calvert County, Maryland” by Richard Orr (reference 2).

Four-Spotted Pennant/Brachymesia gravida
S3 Watch List (see below for definition)
A larger member of the family, it prefers coastal habitats including brackish areas. (1)
Cove Point adult abundance and flight period – common/17-Jun to 03-Sept. (2)
iNaturalist research grade observations:​ Calvert = 5 (Jun-Jul) St. Marys = 1 (Jun) Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Red-veined Pennant/Celithemis bertha
In southern Maryland, this species is only found at St. Marys State Park and was first discovered there in 2014. (Maryland Biodiversity website).
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present Charles - X

Calico Pennant/Celithemis elisa
Some think that a better common name for this species would have been “Valentine Pennant” to call attention to the small, red heart-shaped markings that adorn the top of several abdominal segments of the males. (1)
Cove Point adult abundance and flight period – common/21-May to 22-Aug. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 2 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Halloween Pennant/Celithemis eponina
The author says that this might be his favorite English dragonfly name because the name is so appropriate with the orange wings and brown spots. It was not until 1996 that the Dragonfly Society of America approved the idea of creating “common names” for dragonflies. The idea was not embraced by some dragonfly purists. (1)
Cove Point adult abundance and flight period – common/04-Jun to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 11 (Jun-Aug) St. Marys = 1 (Aug) Charles = 5 (Jun-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Banded Pennant/Celithemis fasciata
S3 Watch List (see below for definition)
This species appears to be in decline. Ponds that have become loaded with algae due to over-fertilization from agricultural runoff is one possible explanation. (1)
Cove Point adult abundance and flight period – uncommon/04-Jun to 07-Jul. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 5 (Jun-Jul)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Double-ringed Pennant/Celithemis verna
S2 State Rare (see below for definition)
The compound eyes of dragonflies contain thousands of facets, or ommatidia, that focus light coming from different directions. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 6 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S2 - Imperiled / State Rare — At high risk of extinction or extirpation due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. Typically occurring in 6-20 populations.

S3 - Vulnerable / Watchlist — At moderate risk of extinction or extirpation due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors. Typically occurring in 21-80 populations.

Anotado por rosalie-rick rosalie-rick, febrero 20, jueves 21:27

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