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Pennsylvania G1 & G2 Forest Species

The following list summarizes the G1 & G2 species on Pennsylvania's Environmental Review List that could be impacted by forest management operations. This list was compiled and provided by the PA Department of Conservation and Natural Resources (DCNR) Bureau of Forestry Natural Heritage Section (02/21/23). SFI and the Pennsylvania SFI Implementation Committee are not involved in the determination of status or ranking for any species.









 Epioblasma rangiana

Northern Riffleshell  LE PE G1 S2 PFBC  

 Alasmidonta heterodon

Dwarf Wedgemussel  LE PE G1G2 S1 PFBC

 Lycopodiella margueriteae

Marguerite's Clubmoss   PE G1G2 S1 DCNR

 Malaxis bayardii

Bayard's Malaxis   PE G1G2 S1 DCNR

 Percina bimaculata

Chesapeake Logperch   PT G1G2 S1 PFBC  

 Pleurobema clava

Clubshell  LE PE G1G2 S2 PFBC  

 Stygobromus stellmacki

Stellmack's Cave Amphipod     G1G2 S1 PFBC  

 Pyrgus wyandot

Appalachian Grizzled Skipper     G1G2Q S1 DCNR  

 Bombus affinis

Rusty Patched Bumble Bee  LE   G2 S1 DCNR  

 Clonophis kirtlandii

Kirtland's Snake   PE G2 SH PFBC  

 Crangonyx dearolfi

Pennsylvania Cave Amphipod     G2 S1 PFBC  

 Myotis sodalis

Indiana Bat  LE PE G2 S1 PGC

 Pycnanthemum torreyi

Torrey's Mountain-mint   PE G2 S1 DCNR  

 Symphyotrichum depauperatum

Serpentine Aster   PT G2 S2 DCNR  

 Villosa fabalis

Rayed Bean  LE PE G2 S1S2 PFBC  

 Paxistima canbyi

Canby's Mountain-lover   PE G2? S1 DCNR  

 Callophrys irus

Frosted Elfin     G2G3 S1S2 DCNR  

 Chenopodium foggii

Fogg's Goosefoot   PE G2G3 S1 DCNR

 Glyptemys muhlenbergii

Bog Turtle  LT PE G2G3 S2 PFBC  
 Isotria medeoloides Small-whorled Pogonia  LT PE G2G3 S1 DCNR  

 Myotis septentrionalis

Northern Long-eared Bat  LT PE G2G3 S1 PGC  
 Papaipema sp. 1 Flypoison Borer Moth     G2G3 S2S3 DCNR  

 Pieris virginiensis

West Virginia White     G2G3 S2 DCNR

 Potamogeton tennesseensis

Tennessee Pondweed   PE G2G3 S1 DCNR  

 Sphalloplana pricei

Refton Cave Planarian     G2G3 S1 PFBC  

 Caecidotea franzi

Franz's Cave Isopod     G2G4 S1 PFBC  

 Stygobromus biggersi

Biggers' Cave Amphipod     G2G4 S1 PFBC  

     Forest species  AGENCY        
     Open, non-forested habitat  DCNR - Pennsylvania Department of Conservation and Natural Resources 
     Cave invertebrates  PFBC - Pennsylvania Fish & Boat Commission  
     Wetland species  PGC - Pennsylvania Game Commission  
     Aquatic species            

LE Listed Endangered - Species for which a final rule has been published in the Federal Register to list the species as endangered. Species is legally protected by the Endangered Species Act.
LT Listed Threatened - A species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.
PE Pennsylvania Endangered - Plant species which are in danger of extinction throughout most of their natural range within this Commonwealth, if critical habitat is not maintained or if the species is greatly exploited by man. This classification shall also include any populations of plant species that have been classified as Pennsylvania Extirpated, but which subsequently are found to exist in this Commonwealth.
PT Pennsylvania Threatened - Plant species which may become endangered throughout most or all of their natural range within this Commonwealth, if critical habitat is not maintained to prevent their future decline, or if the species is greatly exploited by man.
G1 Critically Imperiled - A plant or animal or community, often referred to as G1, that is globally extremely rare or, because of some factor(s), especially vulnerable to extinction. Typically, five or fewer occurrences or populations remain, or very few individuals (
G2 Imperiled - A plant or animal or community, often referred to as G2, that is globally rare or, because of some factor(s), is very vulnerable to extinction or elimination. Typically, six to 20 occurrences, or few remaining individuals (1,000 to 3,000), or acres (2,000 to 10,000 acres or 809 to 4047 hectares),or linear miles (10 to 50 miles or 16 to 80.5 kilometers) exist.
G3 Vulnerable - At moderate risk of extinction or elimination due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats, or other factors.
G4 Apparently Secure - At fairly low risk of extinction or elimination due to an extensive range and/or many populations or occurrences, but with possible cause for some concern as a result of local recent declines, threats, or other factors. 
G#G# Range Rank - A numeric range rank (e.g., G2G3, G1G3) is used to indicate uncertainty about the exact status of a taxon or ecosystem type. Ranges cannot skip more than two ranks (e.g., GU should be used rather than G1G4).
Q Questionable taxonomy that may reduce conservation priority - Distinctiveness of this entity as a taxon or ecosystem type at the current level is questionable; resolution of this uncertainty may result in change from a species to a subspecies or hybrid, or inclusion of this taxon or type in another taxon or type, with the resulting taxon having a lower-priority (numerically higher) conservation status rank. The “Q” modifier is only used at a global level and not at a national or subnational level.
? Inexact Numeric Rank - Denotes inexact numeric rank; this should not be used with any of the Variant Global Conservation Status Ranks or GX (presumed extinct/eliminated) or GH (possibly extinct/eliminated).
S1 Critically Imperiled - Critically imperiled in the nation or state because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state.
S2 Imperiled - Imperiled in the nation or state because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state.
S3 Vulnerable - Vulnerable in the nation or state due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors making it vulnerable to extirpation.
S#S# Range Rank - A numeric range rank (e.g., S2S3 or S1S3) is used to indicate any range of uncertainty about the status of the species or ecosystem.
SH Possibly Extinct (Historical) - Species or community occurred historically in the nation or state/province, and there is some possibility that it may be rediscovered. Its presence may not have been verified in the past 20-40 years. A species or community could become NH or SH (possibly extirpated) without such a 20-40 year delay if the only known occurrences in a nation or state were destroyed or if it had been extensively and unsuccessfully looked for. The NH or SH rank is reserved for species or communities for which some effort has been made to relocate occurrences, rather than simply using this status for all elements not known from verified extant occurrences.

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