Significant additions to the butterflies of the Trinity Alps and Mount Eddy, northern California

4 Pages·1991·3.5 MB·English

by  A M Shapiro

JournalofResearchontheLepidoptera 29(l-2):33-36, 1990(91)
Significant Additions to the Butterflies of the
Trinity Alps and Mount Eddy, Northern California
Arthur M. Shapiro
DepartmentofZoology,UniversityofCalifornia, Davis, California95615
The Trinity Alps and Trinity Divide, including Mount Eddy, are
situated in northwestern California and provide high-montane, sub-
alpineandalpineenvironmentsofgranitic,metamorphic,andultrabasic
substratesfarremovedfromthe SierraNevadaandthusofconsiderable
biogeographicinterest. Thebutterflyfaunisticsandecologyoftheregion
were investigatedby Shapiro, Palm andWcislo (1981), Shapiro,A. M.,
(
C. A. Palm & K. L. Wcislo. 1981. The ecology and biogeography ofthe
TrinityAlpsandMountEddy,northernCalifornia,J. Res. Lepid. 18: 69-
152), who based on five years5 field work reported 115 species. Despite
frequentvisitsinthe subsequenteightfieldseasons, onlyone additional
species has been recorded. However, of the hundreds of additional
records and the twenty-five orthirty new collection sites, a number are
ofspecialinterestandbearonourunderstandingofthebiogeographyof
theregion. Thispaperreportsthemostimportantofthenewinformation
gathered since 1980. It is intended to be used with Shapiro, Palm and
Wcislo (1981). New locality and capture data are presented by species;
page numbers refer to the original text.
The followingare the most significant ofthe new localities, presented
winhithcehftohremyatcaonfAbpepfeonudnidxaIr(eppB.K14-—5-1B4o7)n.anTzhaeK1i5'ntgoapongdraDph—icDalunmsampusiro.n
Since 1981 a large number ofnew 7.5' quadrangles have appeared, so
most ofthe study area is now mapped on a much finer scale. The 7.5'
quadrangles are also identified for the new localities.
Asbestos Gulch: 4 km SW Horse Heaven Meadows; hillside seep with tufa
deposits,unusualvegetation(discussedbelow);TrinityDivide: 1603 m. (Seven
Lakes Basin 7.5')
CrowCreek: Darlingtoniabognearjet. CrowCreekandEForkTrinityRiver,
1220 m. (Mumbo Basin 7.5') BK
Horse Flat Camp: Lowermontane mixedforest, 5.3 kmup Eagle Creekfrom
trailhead, 1450 m. BK
Horse Heaven Meadows: Ledum bog, Castle Creek Road at E Fork Trinity
RiverbelowGreyRocks, 1.6kmWWhalenSummit, 1767m. (SevenLakesBasin
D
7.5')
Additions to Annotated List ofSpecies
2. Oeneis nevadensis Felder and Felder, (p. 92)
RECORDS: Horse Heaven Meadows, 21.VI.86.
4. Cercyonispegala boopis Behr. (p. 93)
RECORDS: Deadfall Meadow, 22.VI.86.
34 J. Res. Lepid.
21. Phyciodes orseis orseis Edwards, (p. 99)
RECORDS: HorseHeavenMeadows,21.VL86;DeadfallMeadow(3),22.VI.1986.
33. Precis coenia Hbn. (p. 103)
RECORDS: Horse HeavenMeadows, 21.VI.86.
34. Limenitis lorquini Bdv. (p. 103)
RECORDS: Horse HeavenMeadows, 22.VI.86.
37. Lycaena arota Bdv. (p. 104)
RECORDS: Horse Heaven Meadows, 5.DC.87.
41. Lycaena mariposa Reak. (p. 106)
RECORDS: Horse HeavenMeadows, 21.VI.86, 5.IX.87.
49A. Mitourajohnsoni Skinner. Johnson’s Hairstreak.
The only additional species from the region, a large female collected from
flowers ofLedumglandulosum Nutt. var. californicum (Kell.) Hitchc.
RECORDS: Horse Heaven Meadows, 21.VI.86.
54. Callophrys lemberti Tilden. (p. Ill)
RECORDS: MountEddy summit, 18.VI.89.
57. Glaucopsychepiasus Bdv. (p. 112)
RECORDS: CoffeeCreek,1000m,20.VI.89;HorseFlatCamp,21.VI.89;Deadfall
Meadow (4), 22.VI.1986.
66. Agriadesglandon Prunner. (p. 115)
RECORDS: Horse HeavenMeadows, 21.VI.86; Crow Creek, 21.VI.86.
71. Neophasia menapia Feld. & Feld. (p. 117)
RECORDS: Horse HeavenMeadows, 5.DC.87.
88A. Euphyes vestris Bdv. (p. 123)
RECORDS: Crow Creek(4), 21.VI.1986.
94. Hesperia harpalus Edwards (.H. “comma complex”) (p. 124)
As noted in the original text, Trinity-Eddy populations are extraordinarily
variable. On5.IX.1987aseriesof70specimens(29 ?,41 /)wastakenonthetufa
exposure nearAsbestos Gulch in the Trinity Divide. This represented a small
fractionofthenumberofanimalsflyinginthedensestpopulationofthiscomplex
Ihaveeverseenoutsidehighdesert. Thevariabilitywas extreme, evenforthis
region. A sample is illustrated in figs. 1 and 2. The most extensively-marked
maleswerestronglyreminiscentofH. lindseyiHolland. Alloftheanimals,along
withPolitessabuleti Bdv. andHesperiajuba Scudder,werevisitingflowersofa
dwarfed ecotype ofrabbitbrush, Chrysothamnus nauseosus (Pall.) Brit, which
was the aspect dominant on the site. Associated with it were Cirsium breweri
(Gray) Jeps. (mostly already setting seed) and Triglochin maritima L., both
stronglycalciphilic and the lattervery local inland.
100. Carterocephaluspalaemon Pallas, (p. 126)
RECORDS: Horse Heaven Meadows, 21.VI.86.
104. Erynnis icelus Scud. & Burg. (p. 127)
RECORDS: Horse Flat Camp, 21.VI.89; Horse HeavenMeadows, 21.VI.86.
107. Erynnispersius Scudder. (p. 128)
RECORDS: Horse Heaven Meadows, 5.IX.87.
col- the
(not
complex"
5JX.1987
"comma
Co.,
HesperiaTrinity
1).
Gulch,
some
fig.
of as
Asbestos
Surfaces
individuals
near
Ventral
lecfed same
2.
Fig.
col-
complex"
5.SX.1987.
comma
" Co.,
Trinity
Hesperia
Gulch,
some
of
Asbestos
surfaces
near
Dorsal
lected
36 J. Res. Lepid.
Discussion
Most of the Horse Heaven Meadows records represent either first
collections or significant range extensions within the Trinity Divide,
which has been rather poorly documented except for Mount Eddy and
DeadfallMeadow. MostoftheTrinityDivideisrelativelylowandheavily
forested, and until very recently 7.5' topographic quadrangles were not
available for it. It is crisscrossed by old logging and mining roads and
Jeeptrails, andbyrelativelyrandomwanderingonthemitispossibleto
encounterunusualhabitats, includingtheLedumbogatHorseHeaven,
theDarlingtonia bog at Crow Creek, and the tufa exposure atAsbestos
Gulch, all of which produced important records. The Crow Creek
Euphyes vestris connect the previously-known and isolated colonies at
ScottMountainSummitandMountShastaCity, andsuggestthatmany
other colonies of this very local skipper may exist in the region.
Carterocephalus palaemon was previously unrecorded in the Trinity
Divide. ThemanyspeciescollectedatHorseHeavenandelsewhereinthe
vicinitydocumenttheecologicalbreadthwhichallowsthemtotranscend
the edaphic and vegetational complexity of northern California; the
montane fauna is much more eurytopic thanthe sub-alpine and alpine.
At least one species enters the eastern fringe ofthe Trinity Divide, but
fails to extend more than about 6 km west ofInterstate 5. This is the
—
apparentLycaena editha Mead L. xanthoides Bdv. intergrade, which
iscommonatDunsmuirandextendslocallywestwardalongtheCallahan-
GazelleRoad,butisotherwise absentformtheTrinities andEddies. Its
distribution does not correlate very well with climate or vegetation.
TheAsbestosGulchseriesofHesperia,embracingasmuchvariationas
occurs in the entire region, includes specimens which if taken out of
context could be called three different subspecies. One wonders how
many taxonomic decisions have been predicated on such small and
unrepresentative samples!
Acknowledgments. This researchhas been supportedby CaliforniaAgricultural
Experiment Station project CA-D*-AZO-3994-H, “Climatic Range Limitation of
PhytophagousLepidopterans.” IthankDavidOlson, LindaFarley, BillOverton,
JohnWagoner,andHansjiirgGeigerforfieldassistance. Thephotographsareby
SamuelW. Woo.