A systematic revision of the Shovel-nosed Salamander (Plethodontidae: Desmognathus marmoratus), with re-description of the related D. aureatus and D. intermedius
Author
Pyron, R. Alexander
0000-0003-2524-1794
rpyron@colubroid.org
Author
Beamer, David A.
0000-0003-2524-1794
rpyron@colubroid.org
text
Zootaxa
2023
2023-04-20
5270
2
262
280
http://dx.doi.org/10.11646/zootaxa.5270.2.5
journal article
255189
10.11646/zootaxa.5270.2.5
5df54694-df76-4304-8adc-c750a0c1c7eb
1175-5326
7850637
203D4821-2C0D-4ECB-9298-05EE363D1F05
Desmognathus intermedius
(
Pope, 1928
)
Leurognathus marmorata intermedia
Pope, 1928
Leurognathus marmorata melania
Martof, 1956
type specimen UMMZ 111564 by original designation, collected 4 Sepember 1954 by “the Bernard Martof family,” type locality “Otter Creek, tributary of the Nantahala River, 0.5 of a mile west of Tellico Gap, Macon County,
North Carolina
;
3,600 feet
elevation.”
Paratypes
UMMZ 111565 (
20 specimens
); same data. Informally synonymized with
L. marmoratus
by
Martof (1962)
and resurrected by
Dubois and Raffaëlli (2012)
and
Raffaëlli (2013)
as
D. “melianus”
in error, though few subsequent workers followed this recommendation. Designated a junior subjective synonym of
D. intermedius
by
Raffaëlli (2022)
.
Holotype
:
AMNH 25557
(a male) by original designation, collected
17 July 1927
by
C.H. Pope
, type locality “
Davis Gap
,
Waynesville
,
North Carolina
” and emended by
Bishop (1943)
to “
Davis Farm
, about
2 miles
east and a little north of
Waynesville
, (
Haywood County
) on Highway No. 276.”
Paratypes
:
AMNH 25544–25556
& 25558–25580 from the original type collection are listed as paratypes in the
AMNH
catalogue, but not explicitly designated as such by
Pope (1928)
.
Description:
Among shovel-nosed salamanders,
Desmognathus intermedius
can be diagnosed from
D. aureatus
by the presence of vomerine teeth in adults of both sexes, and from
D. marmoratus
by a more scattered and indistinct dorsal pattern in adults (after
Pope 1928
;
Pope and Hairston 1947
;
Fig. 8
,
9
). These characters should be re-evaluated for diagnostic consistency. Ironically given the original intent of the name “
intermedius
,” this is by far the largest shovel-nosed species in our sample with metamorphosed SVL =
28–85mm
. Based on our size-corrected linear morphometric analyses, this species can be distinguished from both
D. aureatus
and
D. marmoratus
by a longer trunk (AG in original measurements =
14–45mm
) and from
D. marmoratus
by a longer head (SG in original measurements = 6.5–20.0mm). After
Martof (1962)
and
Bruce (1985)
, larvae are generally
15–35mm
SVL, with a 3-year period until metamorphosis and oviposition and transformation both occurring in summer.
FIGURE 8.
A large (75mm SVL) adult
Desmognathus intermedius
(RAP2814)
from Wycle Fork (NC: Haywood) in life. Note the faded lichenous dorsal patches muddled into more indistinct blotches. Photo courtesy of MAS.
Range:
In the Blue Ridge Mountains of western
North Carolina
and eastern
Tennessee
, confirmed in the
Tennessee
drainages of the Lower Little
Tennessee
, Upper Little
Tennessee
, Tuckasegee, Lower French Broad, Pigeon, and Upper French Broad Rivers (
Fig. 1
). Curiously rare in or absent from the upper reaches of the Little
Tennessee
and Tuckasegee Rivers (
Martof 1962
,
1963
). An isolated population is known from the Black Mountains east of the French Broad River in the Upper French Broad drainage (
O’Connell et al., unpubl. data
). Elevational range ~
300–1500m
.
Habitat:
As with all Shovel-nosed Salamanders, occurs almost exclusively in the rocky riffle zones of fast-flowing, high-gradient mountain streams.
Etymology:
The specific epithet is a Latin singular adjective in the nominative case meaning “intermediate,” apparently referring to the species’ supposedly smaller size compared to
D. marmoratus
as known to
Pope (1928)
based on relatively few specimens.
FIGURE 9.
An adult
Desmognathus intermedius
from Little Santeetlah Creek (NC: Graham). Note the uniformly muddled dorsal blotches forming an indistinct pattern. Photo courtesy of MAS.
Standard English Names:
For
Leurognathus marmorata intermedia
:
Pope’s Salamander (
Bishop 1943
), Southern Shovel-nosed Salamander (
Schmidt 1953
); for
Leurognathus
m.
melanius:
Black
Shovel-nosed Salamander (
Conant 1958
), Otter Creek Dusky Salamander (
Fouquette and Dubois 2014
). We suggest that “Western” Shovel-nosed Salamander is most appropriate.
Conservation:
This species is apparently widespread and abundant at numerous historical and recent sites across its range, a significant proportion of which is protected by state, federal, and private entities. Consequently, we suggest that it be considered “LC—Least Concern” based on available data (
Maes
et al.
2015
).
Notes:
This lineage was previously recognized as a distinct species
Leurognathus intermedia
by
Pope and Hairston (1947)
before being demoted to a subspecies
L. m.
intermedia
by
Schmidt (1953)
and informally synonymized with
L. marmoratus
by
Martof (1962)
.