Desmognathus balsameus sp. nov.

Holotype: AMNH A-193885 (RAP0650; Fig. 16), collected 12 April 2019 by RAP from Bubbling Spring Branch near Mount Hardy Gap (NC: Haywood; 35.308, -82.908, ~ 1530m ASL).

Paratypes: AMNH A-193884 & A-193886 (RAP0649 & 0651), as from the type. MNHN 2021.0115 & BMNH 2021.7526 (RAP0644–5), collected 12 April 2019 by RAP on Green Ridge (NC: Haywood; 35.353, -82.917), ~ 1110m ASL. NCSM 108355 (RAP0647), collected 12 April 2019 by RAP near Sunburst Falls (NC: Haywood; 35.338, -82.904), ~ 1260m ASL.

Diagnosis: Several phenotypic characters exhibit varying combinations of states which are purported to be diagnostic and differentiate D. balsameus from related or similar taxa. This species is a small (~ 19–47mm SVL; n = 22), primarily terrestrial mountain dusky salamander with a tail shorter than the body (up to ~90% SVL) that is round in cross section along its length. It is differentiated from D. santeetlah by the lack of any keeling on the dorsal surface of the tail (vs. presence thereof), which is the only species in its range with which it is likely to be confused. Exhibits a wide range of color patterns, with most individuals possessing a partially or mostly complete dorsal stripe with wavy or undulating edges (vs. usually straight in D. adatsihi), formed from the irregular invasion of melanophore patches between the remnants of paired larval spots, with a brownish, yellowish, or reddish coloration against a darker lateral ground color, and a general lack of any regular patterning along the mid-dorsal line (Figs. 17–18). Ontogenetic darkening seems to be relatively more common and at smaller sizes than in related species, with individuals as small as ~ 33mm SVL exhibiting overall dark brown to blackish coloration obscuring the dorsal pattern (Fig. 12b, 14b, 18b, 19a).

Distribution: In the Great Balsam Mountains of western North Carolina at elevations above ~ 1000m ASL, primarily in Haywood, Jackson, and Transylvania Counties, but possibly extending into western Buncombe and Henderson Counties (Fig. 4).

Etymology: From the Latin balsamum for “balm,” after the Fraser fir trees (Abies fraseri), known in the past as the “she-balsam” or “balsam fir” for which the Great Balsam Mountains are also named (Fig. 19b), though now treated as distinct from the Balsam fir A. balsameus. Name is a Latin singular adjective in the nominative case, masculine gender. We suggest the common name “Great Balsams” Mountain Dusky Salamander.

Notes: Comprises the ocoee B lineage defined by Kozak et al. (2005), Beamer & Lamb (2020), and Pyron et al. (2020, 2022c).

The fourth species in our taxonomy represents the resurrection of Desmognathus perlapsus Neill, 1950 for the ocoee C/D lineage, which shares hybrid non-lineal mitochondrial ancestry with the Balsam clade but is otherwise genealogically exclusive and topologically distinct from D. adatsihi and D. balsameus (see Pyron et al. 2022c). The primary expansion of this taxon concept here is the inclusion of populations previously referred to D. conanti from the Chattahoochee River drainage in the Piedmont of Georgia and Alabama, as reported by Beamer & Lamb (2020) and corroborated by Pyron et al. (2022c). The ocoee C lineage reported by Kozak et al. (2005) is a member of this species and exhibits reciprocal admixture with adjacent ocoee E and possibly ocoee F/G/H populations in the southern Nantahala Mountains (Pyron et al. 2022c). The ocoee D lineage is otherwise genetically cohesive and comprises northern and southern phylogeographic sublineages with a broad hybrid zone across the Blue Ridge/ Piedmont transition. Correspondingly, we offer a re-description of: