27 de marzo de 2020

Calvert County Damselflies & Dragonflies: Part 16 – Damselflies of the Family Lestidae

Family: Lestidae (Spreadwings)

In the Richard Orr Maryland database, there are eleven Spreadwing damselfly species listed for the state. Only five of those species are listed as present in at least one the three southern Maryland counties.

The iNaturalist observation database for the Spreadwing damselflies in the southern Maryland counties is quite sparse. Only two species are recorded from a total of only five observations: Calvert County has a single observation for a Slender Spreadwings, St. Marys County has zero observations, and Charles County has four observations in total from two species (Slender x 3, Great x 1).

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes 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 Spreadwing 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).

Great Spreadwings/Archilestes grandis
The Great Spreadwings is the largest damselfly found in the northeastern US and is a little over two inches in length. (1)
Cove Point adult abundance and flight period – rare/11-Sept to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 1 (May)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X ​ Charles - X

Southern (Common) Spreadwings/Lestes australis
DNA analysis seems to indicate that the Southern Spreadwings and the Common Spreadwings are subspecies of the Sweetflag Spreadwings. (1)
Cove Point adult abundance and flight period – common/23-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Elegant Spreadwings/Lestes inaequalis
The Elegant Spreadwings is one of the larger Spreadwings damselflies in our area. It prefers shallow ponds with plenty of emergent vegetation. (1)
Cove Point adult abundance and flight period – rare/16-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – X Charles - present

Slender Spreadwings/Lestes rectangularis
In contrast to butterflies and moths, damselflies and dragonflies do not emerge from a pupa. Rather the larvae will climb out of the water onto a secure perch and transform into an air-breathing adult in its final molt. (1)
Cove Point adult abundance and flight period – rare/19-May to 29-Aug. (2)
iNaturalist research grade observations:​ Calvert = 1 (Jun) St. Marys = 0 Charles = 3 (Jun-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Swamp Spreadwings/Lestes vigilax
Damselfly larvae have long slender bodies with three flat paddles known as caudal gills attached to the end of the abdomen. In addition to being highly vascularized to exchange oxygen, the gills also function like a fish’s tail for mobility. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Ingresado el 27 de marzo de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

25 de marzo de 2020

Calvert County Damselflies & Dragonflies: Part 15 – Damselfly Introduction and the Family Calopterygidae

Damselfly Introduction:
Maryland is represented by three families of damselflies comprised of a total of 57 species:
1) Calopterygidae (Jewelwings/Rubyspots) with 7 species;
2) Lestidae (Spreadwings) with 11 species; and
3) Conagrionidae (Damsels/Dancers/Bluets/Forktails/Sprites) with 39 species.

Richard Orr’s Maryland database information on the three southern Maryland counties have a reported 31 of the 57 Maryland species with 24 of those 31 species listed in Calvert County. A Cove Point (Calvert County) report lists 18 species as being present at that location with 8 of those being common to abundant.

The iNaturalist database for damselflies in the southern Maryland counties has only 12 species reported and the following number of research grade observations/number of species within each county:
Calvert County = 68 observations/7 species, St. Marys County = 6 observations/4 species, and Charles County = 19 observations/9 species. Obviously, much work remains to be done to bring the two databases closer in alignment.

Family: Calopterygidae (Jewelwings/Rubyspots)

The Ebony Jewelwing is the only member of this family found in southern Maryland and it has been reported in all three counties according to Richard Orr’s database. It is represented in the iNaturalist database for only two of the southern Maryland counties, Calvert and Charles Counties. For this species, my contribution to the Calvert County iNaturalist database has been a pair of observations made from Battle Creek Cypress Swamp where numerous individuals were sighted throughout the park.

Listed below are the observations for the three southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the dragonfly families, I have included 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 this species as 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).

Ebony Jewelwing/Calopteryx maculata
If a female has mated recently, the next male to copulate will remove the previous suitor’s spermatheca from the female and replace it with his own. (1)
Cove Point adult abundance and flight period – common/23-Apr to 29-Jul. (2)
iNaturalist research grade observations:​ Calvert = 28 (May-Aug)​ St. Marys = 0 Charles = 8 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​Calvert – present St. Marys – present​Charles - present

Ingresado el 25 de marzo de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

22 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part 14 – Meadowhawk & Saddlebag Dragonflies of the Family Libellulidae

Family: Libellulidae (Meadowhawks/Saddlebags)

Due to the large number of species present for this family, I have continued to break down this particular family into smaller segments. This grouping is the conclusion for the Libellulidae family and it also concludes the review of the dragonfly families found in southern Maryland. The next set of entries will be a review of the damselfly species of southern Maryland and in particular of Calvert County.

Four of the five species listed below can be found in all three southern Maryland counties according to Richard Orr’s database. The Red Saddlebags is only listed for Calvert County and is thought to probably be a stray species. While four of the five species in this grouping of dragonflies are represented in the iNaturalist database for at least one of the southern Maryland counties, the Blue-faced Meadowhawk (on the S3 Watch List) and the Black Saddlebags only have a single observation with each in Charles County.

For this group, I have made contributions for two of the species to the Calvert County iNaturalist database: 2 of the 3 observations for the Carolina Saddlebags and the first and only observation of an Autumn Meadowhawk dragonfly. These four observations in total for the two species are the only ones in Calvert County for this grouping.

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes 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).

Blue-faced Meadowhawk/Sympetrum ambiguum
S3 Watch List (see below for definition)
This species favors vernal ponds to lay their eggs in late summer/early fall. This strategy avoids fish predators, but runs the risk of the pond drying out before the larvae hatch the following year. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0 Charles = 1 (Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Autumn Meadowhawk/Sympetrum vicinum
On the DelMarVa Peninsula there are reports of this species being present as late as December 8th and even later in New Jersey. It is not known what they do in fall evenings to stay warm. (1)
Cove Point adult abundance and flight period – abundant/14-Oct to 02-Dec. (2)
iNaturalist research grade observations:​ Calvert = 1 (Nov) St. Marys = 0 Charles = 8 (Sept-Nov)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Carolina Saddlebags/Tramea carolina
Prior to 1763 no dragonfly species from what is now the United States had been described. In that year the Swedish botanist Linnaeus described Tramea carolina, the Carolina Saddlebags, a species he never saw alive. (1)
Cove Point adult abundance and flight period – common/05-May to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 3 (Jun-Jul) St. Marys = 0​ Charles = 2 (May-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Black Saddlebags/Tramea lacerata
Dragonflies have evolved capabilities that continue to challenge aircraft engineers such as the transition from hovering to high-speed pursuit. (1)
Cove Point adult abundance and flight period – common/19-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 1 (Oct)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Red Saddlebags/Tramea onusta
Like other saddlebag species, the Red Saddlebags wanders far from its emergence site. Although it normally occurs west of the Mississippi, strays occasionally make it to the eastern US. (1)
Cove Point adult abundance and flight period – rare/29-Jul. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0 Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X​ Charles – X

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
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.

Ingresado el 22 de marzo de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

18 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part 13 – Dasher/Gliders/Amberwing/Whitetail Dragonflies of the Family Libellulidae

Family: Libellulidae (Dasher/Gliders/Amberwing/Whitetail)

Due to the large number of species present for this family, I am continuing to break down this family into smaller segments. This particular grouping is composed of a variety of dragonfly types and the common names sound strangely similar to a herd of Santa’s reindeers.

All five of the species listed below can be found in all three southern Maryland counties according to Richard Orr’s database. Currently only three species in this grouping are represented in the iNaturalist database for all three southern Maryland counties. The two species of Gliders are currently represented by only a single St. Marys County observation of a Wandering Glider.

For this group, I have made contributions for three species to the Calvert County iNaturalist database: 18 of 41 and 10 of 42 observations for Blue Dasher and Common Whitetail dragonflies, respectively and have added all eight observations for the Eastern Amberwing.

Listed below are the species within this group that have been observed in at least one of the southern Maryland counties and a comparison of the two databases is made (as of March, 2020). As was done with the previous family, I have included notes 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 all five of the 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).

Blue Dasher/Pachydiplax longipennis
The Blue Dasher is our most abundant dragonfly all summer long. In July, probably more than half of all dragonflies present are this species. It appears to be expanding its range northward on both East and West Coasts. (1)
Cove Point adult abundance and flight period – abundant/19-May to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 41 (May-Oct)​ St. Marys = 3 (Jul-Aug) Charles = 11 (May-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Wandering Glider/Pantala flavescens
The Wandering Glider is the only worldwide species of dragonfly and is known from every continent except Antarctica. Ships a thousand miles at sea have encountered it. (1)
Cove Point adult abundance and flight period – common/24-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 1 (Sept) Charles = 0
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present Charles - present

Spot-winged Glider/Pantala hymenaea
This is an opportunistic species characterized by a short life cycle and a high dispersal ability. (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 = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Eastern Amberwing/Perithemis tenera
This species exhibits sexual dimorphism which is common among dragonflies and damselflies. But it also exhibits female polymorphism, the biological significance of which is unclear. (1)
Cove Point adult abundance and flight period – abundant/19-May to 03-Sept. (2)
iNaturalist research grade observations:​ Calvert = 8 (Jun-Aug) St. Marys = 2 (Jul-Sept) Charles = 3 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Common Whitetail/Plathemis lydia
The Common Whitetail is a striking example of sexual dimorphism. Males have a bright white abdomen and prominent black bands across both wings. Females have a brown abdomen and several dark patches on the wings. (1)
Cove Point adult abundance and flight period – abundant/21-Apr to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 42 (Apr-Sept) St. Marys = 4 (Apr-Jul) Charles = 11 (Apr-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Ingresado el 18 de marzo de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

16 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part Twelve – Skimmer Dragonflies of the Family Libellulidae

Family: Libellulidae (Skimmers)

Due to the large number of species present for the Family Libellulidae, I have been breaking down the family into smaller segments. This segment will focus on the Skimmer dragonflies which are all contained in a single genus Libellula.

Of the ten species listed below for southern Maryland from Richard Orr’s database, nine of the ten species can be found in all three southern Maryland counties. This includes two of the three species on the S3 Watch List of the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”. In the iNaturalist database for the three southern Maryland counties as of March, 2020, species observations are as follows: Calvert – all 10 species, Charles – 9 species, and St. Marys County only 4 species recorded.

My contributions to the Calvert County iNaturalist database are as follows: entered a total of 44 observations of skimmers which included 8 of the 10 species present, but three of the eight species recorded were the result of a single observation. And of those three species, the Golden-Winged Skimmer and the Bar-Winged Skimmer are on the S3 Watch List and warrant a closer examination to insure proper identification. The Golden-Winged Skimmer was observed near the fresh water pond at Calvert Cliffs State Park which would be consistent with its expected habitat, but it can be difficult to differentiate from the Needham’s Skimmer dragonfly.

Listed below are the Skimmer 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 March, 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 Pennant species of this family 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).

Golden-Winged Skimmer/Libellula auripennis
S3 Watch List (see below for definition)
This species is difficult to distinguish from the Needham’s Skimmer and it has not yet been confirmed on the DelMarVa peninsula. (1)
iNaturalist research grade observations:​ Calvert = 1 (May) St. Marys = 0 Charles = 2 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X Charles – present

Bar-Winged Skimmer/Libellula axilena
S3 Watch List (see below for definition)
This skimmer frequently selects perches on dead tree twigs, sometimes more than 20 feet above vernal ponds. (1).
Cove Point adult abundance and flight period – rare/14-Jun to 08-Jul. (2)
iNaturalist research grade observations:​ Calvert = 2 (May-Aug)​ St. Marys = 0​ Charles = 1 (May)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Spangled Skimmer/Libellula cyanea
Along the front edge near the tip of each wing of a dragonfly is a pigmented spot called the stigma. Because this feature is absent in many fossilized dragonfly wings, it is relatively new by geological standards and is presumed to be important. (1)
Cove Point adult abundance and flight period – common/19-May to 08-Jul. (2)
iNaturalist research grade observations:​ Calvert = 4 (Jun-Jul)​ St. Marys = 0​ Charles = 6 (Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Yellow-Sided Skimmer/Libellula flavida
S2 Rare/S3 Watchlist (see below for definition)
Some 1920’s publications suggest that this species was once common on the Western Shore of the Chesapeake Bay, but certainly that is not the case today. (1)
Cove Point adult abundance and flight period – rare/24-May to 24-Jul. (2)
iNaturalist research grade observations:​ Calvert = 1 (Jul) St. Marys = 0 Charles = 2 (Jun-Jul)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Slaty Skimmer/Libellula incesta
Dragonfly larvae breathe by constantly circulating water over rectal gills that line the inside of the abdomen and extract oxygen from the water. (1)
Cove Point adult abundance and flight period – common/04-Jun to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 12 (Jun-Aug) St. Marys = 2 (May-Jul)​ Charles = 9 (Jun-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Widow Skimmer/Libellula luctuosa
Dragonflies that have emerged have small spiracles (holes) on the sides of their bodies where air enters a branching labyrinth of smaller and smaller tubes (tracheae). This enables oxygen to diffuse over a relatively short distance. (1)
Cove Point adult abundance and flight period – common/19-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 11 (Jun-Jul) St. Marys = 4 (Jun-Sept)​ Charles = 8 (Jun-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Needham’s Skimmer/Libellula needhami
The species is named for James Needham, an entomology professor at Cornell University, by one of his students. It is abundant along salt marshes and rarely found at inland ponds. (1)
Cove Point adult abundance and flight period – abundant/19-May to 14-Oct. (2)
iNaturalist research grade observations:​ Calvert = 50 (Jun-Aug)​ St. Marys = 4 (Jun-Aug)​ Charles = 14 (Jun-Aug)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Twelve-Spotted Skimmer/Libellula pulchella
When a dragonfly locks onto a prey, it is able to adjust its flight so that it takes a direct line to an intercept point rather than a longer sweeping arc that would be generated by always flying directly toward the prey. (1)
Cove Point adult abundance and flight period – rare/17-Jun. (2)
iNaturalist research grade observations:​ Calvert = 1 (Jun)​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Painted Skimmer/Libellula semifasciata
At their breeding sites, most dragonflies are territorial. Males find prominent perches overlooking the territory they will defend and normally return to that same perch after each time they fly out to challenge an intruder. (1)
Cove Point adult abundance and flight period – uncommon/04-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 4 (May-Aug)​ St. Marys = 0​ Charles = 1 (Jun)
MD Biodiversity (i.e., Richard Orr): ​Calvert – present St. Marys – present​ Charles - present

Great Blue Skimmer/Libellula vibrans
In most years Great Blue Skimmers are scarce, but in wet years when woodland pools fill up with water in the spring and stay wet into the summer, Great Blue Skimmers are common. (1)
Cove Point adult abundance and flight period – uncommon/24-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 26 (May-Aug)​ St. Marys = 4 (May-Aug) Charles = 19 (May-Sept)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ 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.

Ingresado el 16 de marzo de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

03 de marzo de 2020

Calvert County Dragonflies and Damselflies: Part Eleven – Pondhawk/Dragonlets/Corporal Dragonflies of the Family Libellulidae

Family: Libellulidae (Pondhawk/Dragonlets/Corporal)

Due to the large number of species present for this family, I will continue to break down this family into smaller segments. This particular grouping is composed of a variety of dragonfly types.

Three of the four species listed below can be found in all three southern Maryland counties according to Richard Orr’s database. The S1 - Critically Imperiled / Highly State Rare Little Blue Dragonlet is only known from Calvert and Charles Counties and is currently lacking any southern Maryland iNaturalist observations. Both the Eastern Pondhawk and Blue Corporal dragonflies are represented in the iNaturalist database for each of the three southern Maryland counties. For this group, I have made a small contribution to the Calvert County iNaturalist database: seventeen of the 59 Eastern Pondhawk observations and one of the eight observations for the Seaside Dragonlet.

Listed below are the species within this group 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 notes 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 three 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).

Eastern (Common) Pondhawk/Erythemis simplicicollis
This is one of our most common and widespread dragonflies. It is a formidable predator that has a preference for larger prey including large flies, butterflies, and even other dragonflies. (1)
Cove Point adult abundance and flight period – abundant/05-May to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 59 (May-Oct)​ St. Marys = 9 (May-Sep) Charles = 11 (May-Sep)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Seaside Dragonlet/Erythrodiplax berenice
This is the only truly marine dragonfly in the world in that its larvae can live in seawater. (1)
Cove Point adult abundance and flight period – uncommon/24-May to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 8 (Jun-Jul) St. Marys = 3 (Jun-Aug) Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Little Blue Dragonlet /Erythrodiplax minuscula
S1 - Critically Imperiled / Highly State Rare (see below for definition)
The first documented occurrence on the DelMarVa peninsula of this Maryland rarity did not occur until July, 2009. (1)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X Charles - present

Blue Corporal/Ladona deplanata
This dragonfly is one of the earliest dragonflies to emerge in the spring. (1)
Cove Point adult abundance and flight period – abundant/01-Apr to 21-May. (2)
iNaturalist research grade observations:​ Calvert = 2 (Apr-May) St. Marys = 1 (Apr) Charles = 5 (Apr-Jun)
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S1 - Critically Imperiled / Highly State Rare — At very high risk of extinction or extirpation due to very restricted range, very few populations or occurrences, very steep declines, very severe threats, or other factors. Typically occurring in five or fewer populations.

Ingresado el 03 de marzo de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

20 de febrero de 2020

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.

Ingresado el 20 de febrero de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

14 de febrero de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Nine – Dragonfly Family Corduliidae

Family: Corduliidae (Baskettails/Sundragons/Emeralds)

This is another family of dragonflies that is severely under-represented in the southern Maryland iNaturalist observational database. There is but a single observation in total for the three counties and that is for a Common Baskettail observed in Calvert County. Of the nine species listed below for southern Maryland from Richard Orr’s database, all nine can be found in Charles County, five of the species in St. Marys County, and five in Calvert County. A major consideration is that five of the nine species are listed on the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”. So while much work remains to be done in order to bring the iNaturalist observations closer to the definitive database of county sightings, the rarity of many of these species will probably require a specialized effort to find them.

Listed below are the species within the Corduliidae 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 January, 2020). As was done with the previous family, I have included with each 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 family 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).

Common Baskettail/Epitheca (Tetragoneuria) cynosura
All damselflies and some dragonflies (darners) oviposit by using a sharp ovipositor to deposit their eggs within tough plant tissue. The thought is that most dragonfly families evolved away from this mechanism of egg laying. The female Common Baskettail extrudes her eggs into a gelatinous mass which becomes attached to floating objects in the water. (1)
Cove Point adult abundance and flight period – common/01-Apr to 14-Jun. (2)
iNaturalist research grade observations:​ Calvert = 1 (Apr) St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​ Charles - present

Prince Baskettail/Epitheca (Epicordulia) princeps
Dragonflies are aquatic insects for most of their lifecycle, but as adults they transition into terrestrial insects. Dehydration in the adults becomes a major problem throughout their terrestrial period. (1)
Cove Point adult abundance and flight period – rare/04-Jun. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Robust Baskettail/Epitheca (Tetragoneuria) spinosa
S1/S2 State Rare (see below for definition)
Baskettails underwent a classification revision in 1966 although not everyone has yet to accept the proposed revision. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Selys’ Sundragon/Helocordulia selysii
S2 State Rare (see below for definition)
The first known specimen of this species was collected in DelMarVa in 1937. It would be almost 70 years before the second record of the species was made in DelMarVa in 2006. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X​ Charles - present

Uhler’s Sundragon/Helocordulia uhleri
This species has not been recorded for the DelMarVa peninsula. (1) It is only known from four counties within all of Maryland.
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – X Charles - present

Fine-lined Emerald/Somatochlora filosa
S2 State Rare (see below for definition)
The Great Cypress Swamp of DelMarVa forms the headwaters of the Pocomoke River and once covered an area of nearly 60,000 acres. The swamp is also known as the Burnt Swamp as a result of an eight year fire within its boundaries. Remnants of the Great Cypress Swamp can still be found in Trap Pond State Park in Delaware and in the Pocomoke River State Park of Maryland. These are among the few places where the Fine-lined Emerald can be found. (1)
Cove Point adult abundance and flight period – rare/29-Aug to 30-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0 St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – X​ Charles - present

Mocha Emerald/Somatochlora linearis
S3 Watch List (see below for definition)
For those interested in creating a life list for dragonflies, it is important to consider visiting different types of sites, different seasons, and even different times of day. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles - present

Treetop Emerald/Somatochlora provocans
S1 (see below for definition)
While some Emerald dragonflies are southern in their distribution, the majority are closer to a Canadian distribution and inhabit bogs, peat-stained streams, and alpine lakes. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Clamp-tipped Emerald/Somatochlora tenebrosa
Emeralds have a special allure for dragonfly enthusiasts because they are challenging to ID, are generally scarce, and even when present are almost always elusive. (1)
Cove Point adult abundance and flight period – uncommon/16-Jun to 11-Sept. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
S1 - Critically Imperiled / Highly State Rare — At very high risk of extinction or extirpation due to very restricted range, very few populations or occurrences, very steep declines, very severe threats, or other factors. Typically occurring in five or fewer populations.
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.

Ingresado el 14 de febrero de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

11 de febrero de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Eight – Dragonfly Family Macromiidae

Family: Macromiidae (Cruisers)

There are only four known species of this family in the official Maryland state record. Only two of the four species are listed for southern Maryland and only one of those for Calvert County. Within the iNaturalist database, observations for species within this family are quite sparse for the entirety of Maryland. There are currently no observations recorded in iNaturalist for this family of dragonflies in the three southern Maryland counties.

Listed below are the two species within the Macromiidae family that have been observed in southern Maryland counties and a comparison of the two databases is made (as of January, 2020). As was done with the previous families, I have included with each 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 single species of this family that was 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).

Stream Cruiser/Didymops transversa
Unlike their larval forms, adult dragonflies and damselflies do not walk. The adult legs are adapted for perching and catching prey, but not walking. (1)
Cove Point adult abundance and flight period – uncommon/21-Apr to 10-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​ Charles - present

Georgia River Cruiser/Macromia illinoiensis georgina
S3 Watch List (see below for definition)
The Georgia River Cruiser is almost indistinguishable from a closely related subspecies, the Illinois River Cruiser. The Illinois River Cruiser can be found in fast flowing streams of the Piedmont while the Georgia River Cruiser prefers slower moving Coastal Plain streams. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ Charles - present

Definitions from the Maryland Department of Natural Resources “List of Rare, Threatened, and Endangered Animals of Maryland”:
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.

Ingresado el 11 de febrero de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario

10 de febrero de 2020

Calvert County (MD) Dragonflies and Damselflies: Part Seven – Dragonfly Family Cordulegasteridae

Family: Cordulegasteridae (Spiketails)

For the entire state of Maryland, there are only five known species of this family in the official state record. Of the five species, only two are in the iNaturalist database for southern Maryland with one each for Calvert and St. Marys Counties. The record for each of those species is the result of a single observation. Charles County has yet to be represented in iNaturalist for this family of dragonflies. Once again, much work remains to be done in order to bring the iNaturalist observations in closer harmony to the definitive database of county sightings.

Listed below are the species within the Cordulegasteridae 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 January, 2020). As was done with the previous families, I have included with each 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 two species of this family 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).

Brown Spiketail/ Cordulegaster bilineata
S3 Watch List (see below for definition)
The Brown Spiketail was once thought to be a geographical or morphological variant of the Delta-spotted Spiketail, but analysis of the mitochondrial DNA has confirmed it is a separate species. (1)
Cove Point adult abundance and flight period – uncommon/31-Mar to 14-June. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present ​Charles - present

Tiger Spiketail/Cordulegaster erronea
S3 Watch List (see below for definition)
Female spiketails will hover over shallow water and then perform multiple dips of the abdomen vertically into the water like a pogo stick, each time depositing an egg into the stream bottom. (1)
iNaturalist research grade observations:​ Calvert = 1 (June) St. Marys = 0​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present​ Charles – present

Twin-spotted Spiketail/ Cordulegaster maculata
Full grown larvae no longer feed in the weeks prior to emergence and the internal processes of metamorphosis occur during this stage. (1)
Cove Point adult abundance and flight period – rare/23 Apr to 10-May. (2)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 1 (Apr)​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – present St. Marys – present Charles - present

Arrowhead Spiketail/ Cordulegaster obliqua
S2 State Rare (see below for definition)
Traditionally, actual insect specimens were required to document species for identification and were then stored along with date and locality information. In some instances photographic records have been accepted for documentation purposes. The only record of this species on the DelMarVa peninsula is from a single photograph. (1)
iNaturalist research grade observations:​ Calvert = 0​ St. Marys = 0​​ Charles = 0
MD Biodiversity (i.e., Richard Orr):​ Calvert – X St. Marys – present​ 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.

Ingresado el 10 de febrero de 2020 por rosalie-rick rosalie-rick | 0 comentarios | Deja un comentario