Dragonflies and damselflies are relatively well known in Delaware, thanks to the efforts of H.B. White, whose Natural History of Delmarva Dragonflies and Damselflies (2011) presents a series of essays on all species known to occur on the peninsula as well as a county distribution checklist.

The regional status and habitat associations of northeastern odonates were assessed by White et al. (2014). Two hundred twenty-eight species of odonates are known from the northeast region, an area that is widely considered to be a “hotspot” for odonate diversity, and 130 of those species are known to occur on the Delmarva Peninsula. 

Seventy-eight (78) species are included on the SGCN list for Delaware, ranging from common species for which the Northeast has high conservation responsibility, to rare species, as well as many species that are at the edge of their ranges in the state. Several species, such as the Elfin Skimmer and the Sable Clubtail are state Endangered species.

A worldwide assessment of the conservation status of odonates conducted by Clausnitzer et al. (2009) found that only about 1 in 10 odonates are currently threatened with extinction according to IUCN criteria, a relatively low percentage compared to other taxa. Peatlands, low gradient streams and seeps, high gradient headwaters, and larger rivers are habitats that harbor a disproportionate number of imperiled species in our region and should be considered priority habitat types for conservation, monitoring, and management (White et al. 2014). In fact, Collins and McIntyre (2017) found that future climate change will significantly impact the range of all 15 northeastern lotic species in his climate modeling study, even assuming unlimited dispersal. 

Butterflies and Skippers

Forty-seven of the approximately 105 species of butterflies and skippers that occur or have occurred historically in Delaware are considered SGCN. Many Delaware SGCN are associated with relatively rare small-patch habitats such as Piedmont seepage meadows and xeric sand ridge openings. A butterfly of herbaceous wetlands is the Baltimore Checkerspot, a Tier 1 species. 

Butterflies of the families Hesperiidae and Lycaenidae occur in large numbers on the regional and state SGCN lists because many species in these families are small-bodied, relatively weak fliers with very specific host plant requirements, or they have other narrow ecological specializations such as association with specific vegetation communities. In addition, the larvae of many species of Lycaenidae participate in symbiotic relationships with ants, so that both the larval host plant and suitable ant partners must be available for the species to thrive. 

Beginning in the 1990s, researchers have documented a steady decline in Monarch Butterfly (Danaus plexippus) numbers. A primary threat to the Monarch Butterfly is a decline in populations of milkweed, the primary food plant required by caterpillars. The decline in milkweed is partially due to the reduction of open habitats, but in the Midwest, losses are mostly due to the dramatic increase in use of the herbicide Roundup (glyphosate), which has been associated with the mass-planting of genetically modified herbicide resistant corn and soy (Pleasants and Oberhauser 2012). In addition, the widespread use of systemic insecticides such as neonicotinoids within the breeding range of the Monarch poses a considerable threat; illegal logging of fir forests in Mexico has reduced wintering habitat; and extreme weather events in the eastern U.S. may be negatively impacting Monarchs. In 2020 the USFWS developed a species status assessment (SSA) for the Monarch Butterfly and determined that listing it as endangered or threatened was warranted but precluded by higher priority species. After assessing new information on the species submitted after 2020, USFWS updated the SSA in 2024 to reflect new information on the species and proposed listing the Monarch as threatened under the ESA (USFWS 2024).

In recognition of the decline in Monarch Butterflies, the Monarch Joint Venture (MJV) was initiated in 2008 as a partnership of federal agencies, state agencies, non-governmental organizations, and academic programs working together to protect the Monarch and its annual, long-distance migration. Guided by the Monarch Conservation Implementation Plan that is updated annually, the MJV is taking a science-based approach to address conservation issues for Monarchs. The MJV promotes Monarchs as a flagship species whose conservation will sustain habitats for pollinators and other plants and animals. For more information about MJV: http://www.monarchjointventure.org/.  

In 2018, the USFWS conducted an interim SSA on the Frosted Elfin (Callophrys irus) and since 2019 has coordinated range-wide surveys with state agencies and other partner organizations to see if they still occur at historical locations. From 2019 through 2024, surveys conducted in Delaware resulted in no observations of this species at any sites they once occurred. Although the habitat for the Frosted Elfin still occurs in Delaware and is actively managed for this species and its host plant, the Frosted Elfin is likely extirpated from the state.

Moths

Although there have been no known systematic statewide surveys for moths in Delaware, there have been some localized or species-specific surveys conducted by DFW, other professional entomologists, and useful observations by other naturalists. In addition, there are also research-grade observations in iNaturalist that, if vetted, could be added to the growing list of moth species occurring in the state. Currently, more than one thousand species of moths have been documented in Delaware, with some groups receiving greater attention than others. One hundred and nine species of moths were identified as SGCN in Delaware. 

The nocturnal Macrolepidoptera (“larger moths”) of Delaware have been studied in by Heckscher, Gonzon, and others. Still, much of our data is based on regional sources. Important studies by Tuttle (2007), Schweitzer et al. (2011), and Wagner et al. (2011) have greatly improved the readily accessible body of knowledge on northeastern macromoth species of conservation interest.

The larvae of moths in the genus Papaipema (family Noctuidae) bore into the stems and tubers of plants and many are specific to a particular species of plant. Host specificity has resulted in many species becoming rare due to the decline of their host plant. A survey of Brandywine Creek State Park (New Castle County) by Heckscher and Schweitzer (unpublished data) found that the meadow Papaipema fauna was largely intact while the forest understory fauna was mostly depauperate probably due to deer over-browse, non-native earthworms, and non-native plant species. The family of sphinx or hawk moths (family Sphingidae) includes several well-known agricultural pests as well as several rare and declining species. Certain hawk moths are active during the day, and many species can be important pollinators of flowers with long, tubular corollas.

Giant silkworm moths (family Saturniidae) are among the most colorful and spectacular species of Lepidoptera in the world and several of the largest and most beautiful species have recently declined across the Northeast. These declines have been anecdotally attributed to increased spraying of chemicals for mosquitos and other pest control and to increased anthropogenic light pollution, which disrupts the normal nocturnal flight patterns of these insects. The buck moth (Hemileuca maia) is a diurnal silkworm moth closely associated with scrub oak that primarily occurs in serpentine barrens where this oak often dominates the understory. The Buck Moth has experienced notable declines in the northeast due to habitat loss.

The Catocala (underwing) moths are among the most impressive and most species-rich Noctuidae groups in eastern North America. Many species are designated Delaware SGCN due to their dependency on specific host plants that may be uncommon. For example, several species are dependent upon Shagbark Hickory (Carya ovata) which is uncommon in the state outside the Red Clay Creek valley. Other reasons for rarity in this moth group include Delaware’s position at the northern or southern edge of the natural range of several species. Xeric or semi-xeric sand ridges and forests in Sussex County are scattered but highly threatened by development. These forests are often hickory-rich, providing important concentrations of Coastal Plain Catocala populations. Similarly, mesic hardwood forests of the Piedmont often support a mix of several hickory species providing a rich Catocala fauna including some regionally uncommon species. Salicaceae-feeding species may be threatened by SLR including Catocala carissima.

Summerville and Crist (2002) and Summerville (2004) in the U.S., along with Pavlikova and Konvicka (2011) in Europe, have shown that classification of moth functional groups by life form of the larval food source is useful in predicting responses to habitat change. 

Tiger Beetles 

Tiger beetles are a group of highly active, predatory beetles that have been variously classified as either a subfamily (Cicindelinae) within the larger family Carabidae, or a separate family Cicindelidae. The Northeast RSGCN list includes eight tiger beetle taxa. Several tiger beetle species remain common throughout the Northeast, including the Six-spotted Tiger Beetle (Cicindela sexguttata), Bronzed Tiger Beetle (Cicindela repanda), and Punctate Tiger Beetle (Cicindelidia punctulata), which can be found in many urban and suburban areas. Eighteen species are considered SGCN in Delaware. 

Sympatric tiger beetle species (those that occur together in the same habitat) and their larvae are often closely associated with particular microhabitats, especially exposures of different soil types, such as sand or clay (Schultz 1989). Distinct thermal microhabitat preferences have also been described for oviposition (Hoback et al. 2000) and adult activity (Schultz 1998). These specializations make some species susceptible to habitat degradation that alters or eliminates their necessary microhabitats. 

Several tiger beetle species are known to be in decline range wide. These include Cicindela patruela, a pine barrens and ridge-top barrens species that has been lost from many historical sites in the Northeast states, as well as Ellipsoptera lepida, a species that is associated with sand dunes and other open sandy areas across the central and eastern states. Knisely et al. (2014) reviews the conservation status of U.S. tiger beetle species.  

Certain guilds of tiger beetles are known to be at elevated risk for extirpation or even extinction. Population declines have been documented in many species of tiger beetles associated with ocean beaches, including two Northeast RSGCN, the federally listed Habroscelimorpha dorsalis dorsalis and its southern counterpart Habroscelimorpha dorsalis media. Beach-nesting tiger beetles have been found to be sensitive to compaction of sands resulting from human disturbance (Cornelisse 2009), a factor that has probably contributed to the widespread decline of Habroscelimorpha dorsalis. Whereas other beach-dependent species such as piping plover (a shorebird) leave Delaware’s beaches during the winter, tiger beetles spend their entire lives in this habitat and are vulnerable to vehicular use at all seasons. Habroscelimorpha dorsalis dorsalis was federally listed as Threatened in 1990, with a Recovery Plan drafted in 1994 (USFWS 1994).

Delaware’s SGCN tiger beetle list could potentially be expanded, and populations of conservation importance located, with additional survey effort. For example, the tiny pine barrens specialist Cicindelidia abdominalis is found at relatively few sites across the entire Northeast but has large populations in the New Jersey Pine Barrens and occurs on the Maryland portion of Delmarva. This species has been looked for by J. Davis and K. Heckscher in Sussex County, without success, but further inventory is warranted. 

Fireflies

The study of fireflies has a rich history in Delaware, thanks largely to pioneering work by Frank A. McDermott, a chemist who spent his retirement studying this family and, in the process, became one of only a few North American experts on the taxon. McDermott discovered a new firefly species near the town of Bethany Beach in 1946 and named it Photuris bethaniensis, the Bethany Beach Firefly (McDermott 1953). This species was petitioned for listing under the ESA in 2019 and was proposed for listing as threatened under the ESA in 2024. Once thought to be a Delaware endemic, Jason Davis, DFW biologist and biologists from the USFWS and Maryland DNR discovered the Bethany Beach firefly at Assateague Island National Seashore in 2020. In 2021, Virginia Natural Heritage staff discovered it at Chincoteague National Wildlife Refuge, Wallops Island, and False Cape State Park near Virginia Beach. 

Three genera of nocturnal bioluminescent fireflies are widespread in North America: Photuris, Photinus, and Pyractomena. Of the three, the Photuris are the best understood in Delaware, largely because of the work of McDermott, Heckscher, and Davis, while elsewhere more is known about the distribution and abundance of Photinus than Photuris.

The Mysterious Lantern Firefly, Photuris mysticalampas, was discovered and described by Christopher M. Heckscher in 2013 (Heckscher 2013). Like Photuris bethaniensis, its range has expanded outside of Delaware and into Maryland due to increased survey effort. The recently described Photuris mcavoyi was first observed while searching for Bethany Beach Firefly in interdunal swales by James Lloyd in 1968. Lloyd named it Bethany BBB. It was later re-discovered by Hecksher in 1998, but it wasn’t until 2024 that Hecksher described this species and named it Photuris mcavoyi after Bill McAvoy, the Delaware state botanist. Due to its history as an epicenter for the study of North American fireflies, the distribution and abundance of many Delaware species are well known.  

From the collections of McDermott, Pyractomena dispersa was described from the wetlands of the Beaver Valley of the upper Brandywine watershed (Green 1957). In addition, Photuris bethaniensis and Photuris mcavoyi were first described from Bethany Beach and Photuris mysticalampas and Photuris eliza from Phillips Landing. Photuris pennsylvanica is thought to have been first collected and described from the marshes of Wilmington, Delaware (McDermott 1967). Thus, six species have their type locality in Delaware: Pyractomena dispersa, Photuris bethaniensis, Photuris mysticalampas, Photuris pennsylvanica, Photuris mcavoyi, and Photuris eliza.

Most fireflies are associated with wetlands, as the soft-bodied larvae, better known as glowworms, might otherwise be susceptible to desiccation. Soil chemistry, microclimate (e.g., humidity, temperature), or prey items, might also limit the distribution of some species. Due to their affiliation with various threatened wetland types, several species are of high conservation concern. Photuris bethaniensis and Photuris mcavoyi are restricted to rare and threatened interdunal wetlands that occur within the back dunes along Delaware’s Atlantic coast (Heckscher and Bartlett 2004). Interdunal swales are threatened by sea level rise, climate change, coastal development, succession to woody plant species, and invasive plant species. Photuris mysticalampas and Photuris eliza are associated with forested peatland floodplains of high ecological quality in Sussex County (Heckscher 2013). Photuris pennsylvanica is associated with freshwater emergent and shrub wetlands that are usually tidally influenced (Heckscher 2010). All tidal freshwater wetlands are becoming increasingly threatened by sea level rise. Photuris salina and Pyractomena ecostata are both restricted to salt and brackish coastal marshes and therefore may be threatened by sea level rice, adulticides used for mosquito control, and the spread of the invasive Phragmites australis (Heckscher 2010; Heckscher and Lloyd 2015). All fireflies are suspected of being sensitive to pesticide application including those that occur in urban areas. Light pollution is a major threat to insects, especially fireflies, as it can obscure flashing used to communicate for mating. Studies show that light pollution can decrease occurrence, alter behavior, and decrease reproduction of mating fireflies. In general, many species seem to be in regional decline, especially representatives of the genus Pyractomena (Heckscher and Lloyd 2015). Seventeen species of fireflies were identified as SGCN in Delaware. 

Water Beetles

Four species of freshwater beetles were identified as SGCN in Delaware. Water beetles reach high levels of diversity in isolated wetlands, especially vernal pools and Coastal Plain seasonal ponds. With a high density of these habitat types, Delaware, and the Delmarva Peninsula as a whole, are likely a “hotspot” for water beetle diversity. The absence of fish is a major factor influencing community composition and abundance of water beetles in pond habitats (Fairchild et al. 2000). 

The Seth Forest Water Scavenger Beetle (Hydrochus spangleri), a globally critically imperiled beetle known from a single wetland in Maryland since the 1970s, was subsequently found to inhabit a handful of similar sites in the northern part of the Delmarva peninsula, including New Castle County, Delaware (Steiner et al. 2003). Surveys by McIntosh and Short (2012) revealed the continuing occurrence of the species in two small and densely forested vernal pools in northern Delaware.

The primary threat to water beetles is the residential and commercial development of the unprotected, isolated wetlands in which they occur, as well as the surrounding forest matrix. In addition, climate change may affect these species due to their reliance on a shallow, ephemeral wetland habitat combined with apparently very limited dispersal ability. Many species are attracted to lights, so light pollution may be an additional threat for populations in fragmented habitats near residential and commercial areas. 

Other Beetles

Two other species of beetles were identified as SGCN in Delaware. These two species historically occurred in Delaware but there are no recent records. American burying beetle (Nicrophorus americanus) is listed as Threatened under the federal ESA and was once widespread throughout eastern North America but has declined precipitously because of habitat changes.

Considerable concern has been expressed about the conservation status and population trends of native pollinators across North America. Available evidence indicates that certain pollinator species have been declining in the U.S., and flower-visiting insects account for 50% of all known insect extinctions (NRCS 2007). Reduced pollinator populations can result in decreased pollination of plant species that require pollinators for fertilization and reproduction. Nineteen of Delaware’s approximately 300 species of bees were identified as SGCN in Delaware. This list could likely be expanded with increased knowledge of the distribution and conservation status of bees and wasps in the state. 

Solitary Bees

Bumble Bees

Wasps

Declines in pollinator populations are poorly understood in most cases, with potential contributing factors including intensification of agricultural practices, use of certain pesticides, and habitat loss and degradation. Climate change is also expected to pose additional challenges to pollinator populations, including decoupling of plant-pollinator interactions when plants and pollinators respond differently to climate cues. Some bumblebees, particularly Bombus affinis in the east, have experienced declines or range retractions because of the apparent spread of parasites accidentally introduced from European bees used in hothouse tomato production. At least 4 bumblebee species (Bombus affinis, Bombus ashtoni, Bombus fraternus, Bombus variabilis) have been extirpated from Delaware.  The American Bumblebee (Bombus pennsylvanicus) was petitioned for listing under the ESA in 2021. A status review of this species is underway to determine whether the petitioned actions are warranted. 

Most pollinator species are invertebrates and are mostly insects. Major pollinator groups in the Northeast include social and solitary bees, certain groups of solitary wasps, flower flies, as well as many other fly species, beetles, butterflies, and moths. The Xerces Society has published a Red List of Native Bees in Decline (Xerces Society 2014). The Heinz Center (2013) has prepared guidance for incorporating information about the conservation of animal pollinators into Wildlife Action Plans. 

Pollen specialist bees rely on specific plant species, plant genus, or a narrow range of plant species’ pollen to provision to their young. Approximately 25% of the roughly 770 native species of bees in the eastern U.S. are pollen specialists (Fowler 2016). In Delaware, at least 48 of the approximately 300 known species to occur or once known to occur are pollen specialists. These species are especially vulnerable to the loss of host plant availability which is exacerbated by the myriad threats facing insect populations and their habitats. One example, Protandrena abdominalis, is an extremely rare bee species that provisions its young with pollen from a single plant species, Horsemint Bee Balm (Monarda punctata). This bee species was not collected or observed along the east coast in well over 100 years until its discovery at the Nanticoke Wildlife Area by J. Davis in 2020. 

State-wide bee inventory surveys conducted from 2020-2024 by J. Davis with the DFW added a total of 35 species to the state list of bee species. Additionally, these surveys resulted in many new county records of uncommon or rare species. More survey effort is likely to increase the state list of bees as well as the knowledge of native bee distribution and abundance in the state. Older data on Delaware’s native bee fauna is available because of survey work completed by the Delaware Department of Agriculture, Plant Industries Section during the early 2000s. Additional records from museum specimens and the literature were compiled by J. Ascher at the American Museum of Natural History. Parasitic bee groups, including the kleptoparasitic cuckoo bees (Nomada) and the nest parasite cuckoo bumble bees (Bombus subgenus Psithyrus) are now considered especially imperiled due to presumed baseline rarity and declines of their host species.

Although probably not significant pollinators, two Pompilidae (spider wasp) species occur on the SGCN list: Psorthaspis sanguinea and P. mariae. Both species are at or near the northern limit of their distribution and both appear to be dependent on specific edaphic features associated with xeric forests (Heckscher 2014). Psorthaspis sanguinea occurs at Cape Henlopen State Park and this occurrence represents a disjunct population from the North Carolina coast and consequently the only known location in the northeast (Heckscher 2014). 

Delaware’s aquatic macroinvertebrates have been surveyed extensively during water quality monitoring efforts, but in many cases these immature stages are not identified to species level. Thirteen species of freshwater aquatic insects were identified as SGCN in Delaware. 

The Delaware Department of Natural Resources and Environmental Control assesses the water quality in its non-tidal, perennial streams using standard physical, chemical, and biological criteria (Barbour et al. 1999) on a regional basis: Piedmont and Coastal Plain on alternating years. Semiquantitative macroinvertebrate samples are taken during fall low-flow conditions using a D-net (approximately 6 m² per sample) and subsampled to a 200 count. 

Limited species-level survey work on adult caddisflies (Trichoptera) and stoneflies (Plecoptera) was conducted in the early 1980s (Lake 1980, 1984) in Delaware and these published records form the basis for the state lists for those orders. 

Aquatic macroinvertebrates have also been separated ecologically into lotic-erosional (running water riffles), lotic-depositional (running water pools and margins), lentic-limnetic (standing water), lentic-littoral (standing water, shallow shore areas), lentic-profundal (standing water, basin), and beach zone groups (Wallace and Anderson 1996). 

Several species of hydropsychid caddisflies are some of the most imperiled freshwater invertebrates in Delaware. This family consists of mostly lotic-erosional species (Merritt et al. 2008). The caddisfly diversity of Delaware includes at least 143 species (Lake 1984). 

The ecology and habitat associations of North American freshwater mussels were recently reviewed by Haag (2012). As some of the least mobile and longest-living freshwater aquatic organisms, mussels provide a lens to evaluate long-term trends and conditions (Grabarkiewicz and Davis 2008). As filter-feeding bivalves, they are important links in the food chain, filtering bacteria and suspended materials from the water. Their reproduction is complex, relying on species-specific host fish for successful completion of the life cycle. 

The RSGCN list for the northeastern states includes 31 freshwater bivalves, including nine taxa that are high regional responsibility as well as high or very high conservation concern. Six of the RSGCN species are or were present historically in Delaware: Dwarf Wedgemussel (Alasmidonta heterodon), Brook Floater (Alasmidonta varicosa), Yellow Lampmussel (Lampsilis cariosa), Tidewater Mucket (Leptodea ochracea), Eastern Pondmussel (Ligumia nasuta), and Triangle Floater (Alasmidonta undulata). 

Freshwater bivalves are highly imperiled in Delaware. Of the thirteen species known from the state, eleven are considered SGCN and seven species are listed on the Delaware Endangered Species List. 

Dwarf Wedgemussel (Alasmidonta heterodon) was federally listed as Endangered in 1990 and a Recovery Plan developed in 1993 (USFWS 1993). 

Primarily Riverine Species

A few of the Delaware’s freshwater mussel species are closely associated with riverine habitats, including Brook Floater (Alasmidonta varicosa), Dwarf Wedgemussel (Alasmidonta heterodon), and Creeper (Strophitus undulatus). These three species are long-term brooders, requiring suitable spawning conditions in the summer and fall, and access to host fish in the spring and early summer. Host fish include darter, sculpin, and minnows. Dwarf Wedgemussel occurs in small rivers, major tributaries, and on the mainstem near islands on low gradient reaches (Cole et al. 2008).  

Semi-riverine Species 

These species include Alewife Floater (Anodonta implicata), Triangle Floater (Alasmidonta undulata), Yellow Lampmussel (Lampsilis cariosa), and Eastern Elliptio (Elliptio complanata). They are found in a variety of habitats, including small streams, large rivers, and lakes. Yellow Lampmussel and Eastern Elliptio are associated with larger-bodied, mobile host fish. Alewife Floater is also associated with highly mobile host fish, possibly including American Shad and Blueback Herring, in addition to Alewife (Nedeau et al. 2000). Because their host fish are highly mobile, species recruitment is directly related to longitudinal connectivity. Alewife Floater populations have expanded in direct response to the installation of fish passage (Smith 1985). 

Freshwater mussels have declined due to the cumulative impact of numerous threats, including dams, pollution, and declines in host fish populations. Future concerns include potential water temperature and oxygenation effects of climate change, as well as physical impacts of floods and increased severe precipitation events. Some species will be subject to increased salinities from saltwater intrusion related to SLR.  

The Partnership for the Delaware Estuary (PDE) hosts a Volunteer Mussel Survey Program, aimed to find, identify and report freshwater mussels in the Delaware Estuary. DFW has conducted freshwater mussel surveys, finding the state’s highest species diversity in the Chesapeake drainages of Deep Creek (Nanticoke River watershed) and the Choptank River (Heckscher and Bennett 1999). 

From 1997 to 2001 then Delaware Museum of Natural History Curator of Mollusks Dr. Tim Pearce conducted research (funded by the National Science Foundation) on land snails of Delmarva, compiling an unpublished preliminary list of 75 species for Delaware (Pearce, pers. comm.). Twenty-one species of land snails were identified as SGCN in Delaware.

Land snail species richness is significantly higher in high-base sites (Nekola 2005), and it is likely that Delaware land snails are disproportionately diverse in basic mesic forests, as was the case in the coastal Carolinas in Nekola’s study. Species within a region also cluster at the landscape scale according to habitat type, soil surface architecture, geography, moisture levels, and presence of anthropogenic disturbance (Nekola 2003). Land snails are not included in the Species-Habitat Associations compiled in the Delaware Wildlife Action Plan database to insufficient knowledge of their habitat relationships in Delaware. However, most land snails are associated with natural, forested habitats. 

Twenty-one species of freshwater gastropods are known from Delaware based on work by Dillon et al. (2013). Of the 21 species known to occur in the state, 5 were included as SGCN in this revision. 

Robert T. Dillon visited the Dover laboratories of DNREC in January of 2013 and reviewed macrobenthic samples from three years: 2006 (Piedmont), 2010 (Coastal Plain), and 2011 (Piedmont). Approximately 40-50 sites were sampled each of these years, yielding a total of 198 freshwater gastropod records. Supplementing this were specimens from the following institutions: U.S. National Museum in Washington, the Academy of Natural Sciences of Philadelphia, the Carnegie Museum of Natural History in Pittsburgh, and the Delaware Museum of Natural History in Wilmington and personal collections made by the authors within Delaware.