Cercyonis pegala agawamensis Arey and Grkovich, 2014

Arey Alex Grkovich, Matthew D., 2014, Cercyonis pegala agawamensis (Satyridae): A new butterfly subspecies from the coastal salt marshes of the northeastern United States of America, The Taxonomic Report of the International Lepidoptera Survey 7 (8), pp. 1-16 : 4-9

Cercyonis pegala agawamensis Arey and Grkovich , new subspecies

ETYMOLOGY. The type specimens (holotype and allotype) are designated from the former historical settlement and territory of the Native American Agawam Tribe in northeastern Essex County, Massachusetts (ca. 1638) that has historically encompassed the current towns of Ipswich , Rowley , Essex, Newbury , Byfield and Georgetown. We propose the subspecies scientific name as agawamensis and the common name as the Salt Marsh Wood Nymph .

DESCRIPTION. Male somewhat distinct from nearby coastal and inland populations of alope and maritima ; female quite noticeably distinct. Both sexes demonstrate a general brighter “southern look” in comparison to their neighboring inland populations occurring outside of salt marsh habitats.

Male: FW length 25-26 mm. Upperside: Ground color brown. FW apex typically somewhat more pointed than other pegala subspecies. FW eye patch fairly broad (width of patch 10 mm along costal margin), yellow to slightly yellow-orange; eyespots well developed, somewhat small but without tendency in most specimens for lower eyespot to be reduced; occasional specimens however do have lower eyespot reduced or even absent. Pupils sharply defined and centered in light blue. Upper eyespot sometimes reduced in size. HW eyespot well developed, small but with well-defined outer circle of lighter orange-brown; pupiled in light blue. HW submarginal dark line prominent and well defined. Underside: Ground color lighter brown, particularly on outer half of HW. FW yellow eye patch prominent and wide, lower border at inner margin of FW wide and straight. Eyespots well-defined and round in shape, smaller with sharp edges not diffuse as in nearby alope and maritima populations. Dark lines bordering inner and outer edges of FW eye patch prominent; eyespots well-defined and sharply pupiled in light blue. HW eyespots smaller than in typical southeastern Cercyonis but well-defined. Striations sharp and crisp; median and submarginal dark lines prominent.

Female: FW length 29-31 mm. Upperside: Ground color lighter brown than in male; a lighter shade along outer half of HW beyond cell area. FW apex slightly rounded but FW broad and squarish. FW eye patch broad (12-15 mm along costal margin), extending nearly to (and sometimes into) the cell area, color of patch yellow to slightly orange-yellow; yellow patch extends into marginal area in some specimens; margins of patch very sharply defined and not diffuse. FW eyespots as in male, sharply defined without diffuse edges, pupiled in blue; upper eyespot round, lower eyespot somewhat squarish and only somewhat larger. [In nearby alope and maritima both FW eyespots are larger, rounded with diffuse edges, lower eyespot is often significantly larger than upper.] HW eyespot generally smaller than in nominate pegala but with well-defined orange-brown outer circle; submarginal dark line prominent; occasional second smaller eyespot above the main HW eyespot sometimes present. Underside: Ground color lighter brown and somewhat brighter, striations heavy and well-defined; FW eye patch very broad and bright yellow, eyespots as on the above surface, widely pupiled in light blue. Small third eyespot on FW below the lower main eyespot is present. There is no apparent tendency for lower eyespot to be reduced. HW eyespots are typically prominent, but apparently not quite as well developed as in the male.

Phenotypical comparison between C. p. agawamensis and C. p. maritima : We examined a series of males and females of agawamensis from the coastal salt marshes of northeastern Massachusetts and southern New Hampshire, in order to compare these to males and females of maritima from nearby higher “dry old fields”. Males of agawamensis average somewhat distinct from males of maritima ; while females of agawamensis are particularly distinct from females of maritim a.

Males of agawamensis are somewhat larger and average somewhat lighter above than in maritima ; agawamensis males are also somewhat two-toned on the hindwing with the postmedian dark hindwing line often present. Males of maritima have the ground color above darker and more uniformly colored. The orange-yellow forewing eye patch is typically wider and more rectangular in agawamensis males, with the borders of the patch tending to be more clear-cut. The two forewing eyespots are smaller and tend toward equal size in agawamensis. Beneath, the above described characters are essentially repeated: agawamensis males tending to be more two-toned on the hindwing making the hindwing eyespots slightly more prominent; the forewing eye patch tends to be more yellow with less orange tint than in maritima .

Females of agawamensis are, as noted above, particularly distinct in comparison to females of maritima , and are suggestive of smaller examples of females of texana . Females of agawamensis are significantly larger than those of maritima , have much broader wings and have the forewing eye patch very broad. The ground color above is lighter and brighter with the hindwing tending toward two-toned as in the males. The forewing eyespots are rather clear cut and distinct and tend toward being equal in size; while in maritima the eyespots are larger with indistinct edges especially in the lower eyespot. Females of agawamensis have the anal eyespot above small in comparison to females of pegala but always well-defined and circled in orange; maritima females typically lack this eyespot altogether. Beneath, agawamensis females are rather brightly and robustly colored, again suggestive of texana , and differ conspicuously from females of maritima . Agawamensis females below have the forewing eye patch very large, broad and clear cut. The patch typically extends from the postmedian to the submarginal dark line and often extends beyond the submarginal line almost to the outer margin. The eyespots tend to equal size and, as above, are clear-cut with well-defined blue-white pupils. The ventral hindwing is distinctly two-toned with clearly defined postmedian dark line; the eyespots are smaller but at least 4 or 5 are present and fairly well-defined. Maritima females are less noticeably two-toned on the hindwing, the postmedian line is less distinct and the hindwing eyespots are typically absent except for the two near the anal angle, even these are inconspicuous. The forewing eye patch in maritima is narrower and does not extend beyond the submarginal dark line; the eyespots are larger and less clear-cut.

VOLTINISM & PHENOLOGY. Single brooded, diapausal (hibernal) first or second instar larva. The flight period of agawamensis commences during the latter part of the flight period of sympatric C. pegala alope or maritima ; and as currently understood extends from late July through mid September. The peak flight time for agawamensis as noted in surveyed colonies in northeastern Massachusetts and southern New Hampshire is from 28 July to 20 August. Extreme dates of agawamensis as we have observed are 17 July and 26 September. Comparative phenology for C. pegala alope or maritima are very late June through mid August, with peak flights occurring from 12 July to 30 July. Extreme dates for C. pegala alope or maritima are 25 June and 8 September. These phenology and voltinism differences have strong similarity to the recent taxa split of another Satyrid genus Megisto (Hübner) where a late spring flight of Megisto eurytris (Fabricius, sensu Gatrelle) or formerly called M. cymela viola (Maynard) is split from the early summer flight of M. cymela Cramer ) ( Gatrelle, 2005) and these flights often do overlap as does the P. pegala alope / P. pegala agawamensis complex.

HABITAT AND BEHAVIOR. Newly described subspecies agawamensis inhabits coastal salt marshes and estuarine meadows, which are quite atypical as understood for Cercyonis pegala . It predominately prefers and occurs within large open salt marshes but can also be found in similar habitat along smaller tidal rivers, coastal inlets and streams. Adults occasionally wander into adjacent habitats such as old fields, hayfields, wet meadows and open woodland margins and hammocks where they then mingle with nearby populations of C. pegala alope . Dominant halophilic salt marsh plant species in the northeastern U.S. are Cordgrasses ( Spartina alterniflora , S. patens , S. pectinata ), Common Reed ( Phragmites australis ), Spike Grass ( Distichlis spicata ), Black Grass ( Juncus gerardii ), Sea Lavender ( Limonium nashii ), High-Tide Bush ( Iva frutescens ), Salt Marsh Goldenrod ( Solidago sempervirens ), Siff-Leaved Quackgrass ( Agropyren pungens ), Sea Myrtle ( Baccharis halimifolia ), Seaside Gerardi (Agalinus martima), Glassworts ( Salicornia sp. ), Seaside Plantain ( Plantago maritima ), Salt Marsh Aster ( Aster tenufolius ), Widgeon Grass ( Ruppia maritima ) and Switchgrass ( Panicum virgatum ). Larval host plant(s) is (are) likely one or more types of the salt marsh grass species.

However, if habitat - along with phenotype - serves to distinguish agawamensis, then we must also discuss behavior to further distinguish it and differentiate it from its closest relatives. Both sexes fly in open estuarine salt marsh or along tidal waterways. Unlike almost all other populations of C. pegala , agawamensis will often seek nectar from flowering plants, both within the habitat or in nearby adjacent habitat. The adults are more likely to stray from the salt marsh habitat in the latter part of their flight period. Most frequented nectar sources include Purple Loosestrife ( Lythrum salicaria ), Joe-Pye-Weed ( Eupatorium purpurea .), Common Milkweed ( Asclepias syriaca ), Swamp Milkweed ( A. incarnata ), Red Clover ( Trifolium sp. ), Goldenrod ( Solidago sp. ), Asters ( Aster sp. ) and other composites in adjacent habitat. Nectar sources utilized within the estuarine biomes include Salt Marsh Goldenrod ( Solidago sempervirens ), Sea Lavender ( Limonium nashii ) and bordering thickets of Purple Loosestrife.

Agawamensis, unlike either alope or maritima which can and do occur in significant numbers in a relatively small area of their typically DRY old field and meadow habitats, is noticeably communal and is frequently observed perching communally on salt marsh Cordgrasses and associated vegetation in large numbers over a small area. When approached, one or more individuals will take flight, followed in rapid succession by nearly all individuals making up the group. We believe that this behavior serves to confuse a potential predator by making it difficult for the predator concentrate on any one particular individual as prey. As it is perceived that the danger has passed, they will once again perch in similar fashion. While we have never observed this communal behavior in North American Cercyonis , we have observed similar behavior of Neotropical Satyrids (i.e. Taygetis , Cissia , Hermeuptychia etc.), especially toward dusk when their typically brown ground colors effectively conceal them and render this evasive and confusing behavior even more effective. The flight characteristic itself of agawamensis appears to differ from eastern (if not all) Cercyonis , in that its flight as we have observed in the salt marshes is not as “bouncy” or as “jerky” as typical Cercyonis , but is quicker and more straight-ahead 12 to 18 inches above the substrate, suggestive of a typical Erebia or Oeneis rather than of a typical Cercyonis .

As noted elsewhere, agawamensis also differs from all eastern Cercyonis - except for unusual populations of C. pegala “ nephele ” occurring in northern Coos Co., New Hampshire - in that it nectars freely in its salt marsh habitat. These “ nephele ” which we suspect should be further studied, also differ from typical nephele in that they also occur in rather boggy wet meadows and roadsides, nectar freely and frequently on Joe Pye Weed, Everlastings, etc. and also have a fast and rather straight-ahead “unbouncy” flight. We have observed these very blackish populations with very conspicuous ocelli in early to late August at such elevated locations as Pinkham Notch (Mount Washington, 2100 ft.) and at the Scott Bog, East Inlet Road, etc. (above 1900 ft.) near the New Hampshire / Quebec border.

GEOGRAPHIC RANGE AND DISTRIBUTION. Range confirmation for this subspecies is so far restricted to coastal estuarine habitat from southern Essex County , Massachusetts (vicinity of Salem ) extending northward to southern York County , Maine (near Ogunquit ). The greatest and most continuous concentration of this insect occurs in the more extensive coastal salt marshes north of Cape Ann in Massachusetts ( Ipswich River , Parker River and Merrimack River drainages) to the New Hampshire seacoast approximately 12 to 15 Km. south of the Piscataqua River . This encompasses the coastal towns/cities of Essex, Ipswich , Rowley , Newbury , Newburyport and Salisbury in Massachusetts (Essex Co.), and the salt marshes in Seabrook and Hampton (Rockingham Co.) of the southernmost coastline in New Hampshire. This subspecies has also been confirmed in less extensive habitat south of Cape Ann in the Danvers River / North River drainage in the vicinity of Pope’s Landing (Danvers) and the tidal flats within the Forest River drainage system in Salem. Another population occurs in a more extensive estuarine meadow located in Ogunquit, Maine (Piscataqua and Kennebunk River coastal watersheds), which is speculated to be the northernmost range of agawamensis. Habitats south of Essex County, MA, especially in Plymouth, Barnstable and Bristol Counties, and even coastal Rhode Island have yet to be explored. However, there is a strong likelihood that they do occur in the more extensive estuaries and tidal river basins in much of this region. Agawamensis should also be compared to the geographically restricted island populations of subspecies maritima that occur specifically on the islands of Nantucket, Martha’s Vineyard, Block Island ( R.I.) and Naushon Island ( MA.) located in Buzzards Bay . Maritima is also very common in dry weedy open field habitats on mainland Rhode Island, on Long Island, and also near Gettysburg, PA.

TYPE LOCALITY AND TYPE SERIES. TL: Estuarine salt marsh (open), Boston Road, Newbury ( Parker River watershed ), Essex Co., Massachusetts. The holotype specimen will be deposited in the McGuire Centre for Lepidoptera and Biodiversity , Gainesville , Florida. Holotype (female), allotype paratype (male) and all paratypes are identified as follows:

MASSACHUSETTS:

ESSEX CO., Newbury ( Parker River watershed ):

NB001 (female): Boston Road, estuarine salt marsh (open), 7/21/2007 (HOLOTYPE).

NB002 (male): Boston Road, estuarine salt marsh (open), 7/21/2007 (ALLOTYPE).

NB003-NB004 (2 males): Boston Road, estuarine salt marsh (open), 7/21/2007.

NB005-NB006 (2 females): Boston Road, estuarine salt marsh (open), 7/21/2007.

NB010 (female): U.S. Route 1, wet meadow/salt marsh (open), 7/17/2007.

NB011-NB012 (2 males): Boston Road, estuarine salt marsh (open), 7/20/2008.

NB013-NB014 (2 males): Boston Road, estuarine salt marsh (open), 8/2/2008.

NB015 (female): Boston Road, estuarine salt marsh (open), 7/20/2008.

NB016-NB018 (3 females): Boston Road, estuarine salt marsh (open), 7/28/2013.

NB019-NB020 (2 females): Boston Road, estuarine salt marsh (open), 8/2/2008.

NB021 (1 male): Plum Island, salt marsh, 8/14/1999.

NB022-NB023 (2 females): Plum Island, salt marsh, 8/14/1999.

NB024-NB029 (6 males): Boston Road, estuarine salt marsh (open), 7/28/2010.

NB030-NB033 (4 females): Boston Road, estuarine salt marsh (open), 7/28/2010.

NB034-NB038 (5 males): Boston Road, estuarine salt marsh (open), 7/24/2011.

NB039-NB042 (4 females): Boston Road, estuarine salt marsh (open), 7/24/2011.

NB043-NB045 (3 females): U.S. Route 1, salt marsh, 8/12/2011.

NB046-NB050 (5 males): U.S. Route 1, salt marsh, 8/8/2013.

NB051-NB053 (3 females): U.S. Route 1, salt marsh, 8/8/2013.

NB054-NB055 (2 females): Plum Island, salt marsh, 7/24/2003.

ESSEX CO., Essex (Essex River watershed ):

EX001 - EX004 (4 males): Route 133, salt marsh, 7/26/2008.

EX005 - EX007 (3 females): Route 133, salt marsh, 7/26/2008.

ESSEX CO., Ipswich ( Ipswich River watershed ):

IW003-IW004 (2 males): Argilla Road, estuarine salt marsh (open), 7/22/2007.

IW005 (female): Argilla Road, estuarine salt marsh (open), 7/22/2007.

IW006 (female): Argilla Road, old field (coastal), 7/22/2007.

IW007 (male): Argilla Road, estuarine salt marsh (open), 7/9/2013.

IW008 (female): Argilla Road, estuarine salt marsh (open), 7/9/2013.

IW009-IW011 (3 males): Argilla Road, estuarine salt marsh (open), 8/5/2013.

IW012 (female): Argilla Road, estuarine salt marsh (open), 8/5/2013.

ESSEX CO., Newburyport ( Merrimack River watershed ):

NP001 (female): Plum Island Turnpike, coastal salt marsh (open), 7/31/1983.

ESSEX CO., Rowley ( Rowley River watershed ):

RW001 (male): Route 1A, estuarine salt marsh (open), 7/27/2007.

RW002-RW005 (4 males): Route 1A, estuarine salt marsh (open), 7/19/2013.

ESSEX CO., Salem ( Forest River watershed ):

SA001 - SA002 (2 males): Forest River Park, estuarine salt marsh – tidal river basin, 7/22/2007. ESSEX CO., Salisbury ( Merrimack River watershed ):

SB001-SB002 (2 males): U.S. Route 1A, estuarine salt marsh (open), 7/24/2007.

SB003 (female): U.S. Route 1A, estuarine salt marsh (open), 7/20/2008.

SB004 (female): U.S. Route 1A, estuarine salt marsh (open), 7/31/2008.

SB005-SB007 (3 males): U.S. Route 1A, estuarine salt marsh (open), 7/30/2009. SB008-SB011 (4 females): U.S. Route 1A, estuarine salt marsh (open), 7/30/2009. SB012-SB013 (2 females): U.S. Route 1A, estuarine salt marsh (open), 8/3/2009.

MAINE:

YORK CO.; Ogunquit ( Stevens Brook watershed ):

OQ001 (1 male): Furbish Road, estuarine salt marsh (open), 8/1/2007.

OQ002 (1 female): Furbish Road, estuarine salt marsh (open), 8/1/2007.

OQ003 (1 male): Furbish Road, estuarine salt marsh (open), 8/1/2007.

NEW HAMPSHIRE:

ROCKINGHAM CO.; Seabrook ( Blackwater River watershed ):

SK001-SK004 (4 males, dark type): Route 286, estuarine salt marsh (open), 7/24/2007. SK005-SK007 (3 males): Route 286, estuarine salt marsh (open), 8/6/2007.

SK008-SK0010 (3 females): Route 286, estuarine salt marsh (open), 8/6/2007.

SK011 (male): Route 286, estuarine salt marsh (open), 8/6/2007.

SK012 (female): Route 286, estuarine salt marsh (open), 8/6/2007.

SK013-SK015 (3 males): Route 286, estuarine salt marsh (open), 8/6/2007.

SK016-SK017 (2 females): Route 286, estuarine salt marsh (open), 8/6/2007.

Additional locations where C. p. agawamensis have been vouchered:

MASSACHUSETTS: ESSEX CO.: Danvers. MAINE: WASHINGTON CO.: Addison (possible intermediate with C. p. nephele ). NEW HAMPSHIRE: ROCKINGHAM CO.: Hampton.

Locations where C. p. alope have been vouchered for comparison to C. p. agawamensis:

MASSACHUSETTS: ESSEX CO.: Boxford, Georgetown, Groveland , Ipswich, Newbury, Rowley, Topsfield. NORFOLK CO.: Norfolk. BERKSHIRE CO.: Sheffield, Ashley Falls . MAINE: CUMBERLAND CO.: Gorham. YORK CO.: Buxton , Hollis, Saco, York. VERMONT: WINDHAM CO.: Mount Snow, Green River , Guilford .

Locations where C. p. maritima have been vouchered for comparison to C. p. agawamensis: MASSACHUSETTS: WORCESTER CO: Wachusett Mountain . ESSEX CO.: Danvers, Peabody, North Andover , Boston Hill. MIDDLESEX CO.: Melrose ( Middlesex Fells ), Woburn ( Horn Pond Mountain ). DUKES CO. (MARTHA’S VINEYARD): Oak Bluffs ( TL of maritima ), Edgartown . PLYMOUTH CO.: Plymouth, Carver , Middleboro . RHODE ISLAND: PROVIDENCE CO.: Central Falls . WASHINGTON CO.: Westerly, West Kingston . MAINE: ANDROSCOGGIN CO.: Lewiston , Auburn. OXFORD CO.: Oxford .

Locations where C. p. nephele have been vouchered for comparison to C. p. agawamensis:

MASSACHUSETTS: HAMPSHIRE CO.: West Hawley . MAINE: AROOSTOOK CO.: Sherman Mills Twp. KENNEBEC CO.: Augusta, Vassalboro. OXFORD CO.: Streaked Mountain . PENOBSCOT CO.: Dixmont. WALDO CO .: Belfast, Troy, Unity . WASHINGTON CO.: Addison, Cherryfield, Columbia, Columbia Falls, Harrington . NEW HAMPSHIRE: COOS CO.: Pinkham Notch, Pittsburg, Scott Brook Road , East Inlet Road , Clarkston. GRAFTON CO.: Franconia Notch . VERMONT: RUTLAND CO.: Pittsford. GRANDE ISLE CO. : Grande isle .