Ex uno, multis: taxonomic revision in Navarretia divaricata (Polemoniaceae) and the recognition of four additional cryptic or near-cryptic species
Author
Johnson, Leigh A.
https://orcid.org/0000-0002-1026-0944
Department of Biology and M. L. Bean Life Science Museum, Brigham Young University, Provo, Utah 84602, USA
leigh_johnson@byu.edu
Author
Gowen, David
111 Roble Road, Oakland, California 94618, USA
text
PhytoKeys
2017
2017-12-05
91
39
83
http://dx.doi.org/10.3897/phytokeys.91.21530
journal article
http://dx.doi.org/10.3897/phytokeys.91.21530
1314-2003-91-39
466CFFF1FFFFFFFF3372FFF0FFED984D
1138433
Navarretia aeroides L.A.Johnson & D.Gowen
sp. nov.
Figs 4
, 6
Type
.
United States of America
.
California
:
Calaveras County
, west of
Avery
, at the end of a short forest service road off of
Avery Sheep Ranch Road
,
38.19488°N
,
120.39969°W
,
3695 ft
,
17 June 2015
,
D. Gowen
, 1303
(
holotype
BRY! [BRY-627257]; isotypes JEPS!
RSA
!).
Diagnosis.
A species similar to
Navarretia vividior
, but distinguished by being diploid, rather than allotetraploid, and being less robust in all respects;
N. aeroides
has smaller inflorescence heads that are conspicuously stipitate-glandular throughout (sometimes inconspicuously villous proximally), thinner branches, tends toward smaller corollas, and has stem trichomes mostly 0.5mm or less rather than mostly
+/-
1 mm.
Description.
Taprooted annual herbs
to 9(-12) cm tall and 15(-22) cm wide, sometimes larger, often wider than tall. Primary stem erect, terminating in an inflorescence head 1-2(-4) cm above the cotyledons; generally greatly exceeded by secondary stems, with tertiary, and quaternary stems present on larger plants; higher order branches arise from axils of proximal inflorescence bracts, axils of leaves subtending the primary head, or less commonly, leaves within 1 cm of an inflorescence head; branches ascending to spreading and
+/-
leafless, except for leaves subtending higher
order
branches or within 1 cm of a head; stem and branches reddish-brown, glandular-pubescent or sparingly so, the trichomes mostly less than 0.5 mm long; distal-most branches filiform, generally no more than 0.3 mm in diameter. Cotyledons two, linear,
entire
, united at base.
Leaves
somewhat finely stipitate-glandular proximally, less so distally; leaves at the lowermost nodes opposite, linear-filiform, and widened at the point of stem attachment, the proximal nodes often congested with overlapping leaf bases. More distal leaves alternate, entire, or more commonly with 1-3(-5) paired or unpaired linear lateral lobes 1-8 mm long attached along the proximal 3-5(-15) mm of the leaf, with an elongated, linear terminal segment.
Inflorescences
head-like, generally ≤ 10 mm diameter (exclusive of bract tips; ~15 mm with bract tips), mostly less than 10-flowered, sometimes more,
+/-
conspicuously glandular. Inflorescence bracts <10(-12) mm long,
+/-
palmatifid to subpalmatifid; outermost 1-2 bracts with a short achlorophyllous base and 2-3 pairs of lateral lobes flanking an elongate terminal lobe, the distal pair of lateral lobes sometimes shorter and reflexed somewhat out of plane relative to the other lobes; bract bases become larger and clasping centripetally with lateral lobes reduced to a single pair departing from near the apex of the bract base flanking the central terminal lobe, all bract lobes chlorophyllous, entire, long tapering acute. Bracts sparsely glandular-villous abaxially, more densely glandular-villous adaxially and proximally along the lobes just above the rachis, with the stipe of each gland diminishing in length toward the bract tips.
Flowers
actinomorphic,
calyces
mostly 4.0-6.0(-8.5) mm long, tube ~ 1.3-2.2-(2.5) mm; costae entire, long tapering acute, strongly unequal to subequal with typically two costae longer than the other three; costae narrowing proximally, the shorter ones narrower at base than the intercostal membrane and the longer ones subequal with the membrane; calyx tube achlorophyllous, glandular-puberulent on the intercostal membrane and proximal costae, gland stipes lengthen on the costae at the junction with the intercostal membrane, diminishing in length toward the chlorophyllous costae tips; intercostal membrane v-shaped at sinus.
Corolla
generally
+/-
equal to the calyx costae at anthesis but exceeding the calyx as fruit matures, narrowly funnelform, glabrous, 4.2-6.0 mm long, lobes 0.75-1.3 mm long
x
0.5-0.9(-1.0) mm wide, tube white, transitioning to a bluish throat and lobes in some populations (drying bluish purple, with the distal tube showing hints of magenta or somewhat brownish) or remaining white in others (drying with white or light blue lobes and throat with brownish or magenta distal tube); tube base expanding and investing the fruit apex.
Stamen
filaments unequal, 0.2-0.55 mm long, inserted unequally 0.4-0.9 mm below corolla sinuses, anthers included in throat to slightly exserted; pollen blue or white, generally matching corolla lobe coloration, apertures pantoporate, acolpate; sexine seimitectate, reticulate, heterobrochate.
Ovary
three-chambered, stigmatic lobes three, included in to slightly exserted from corolla throat; capsule ~ 2.4-3.4 mm long, dehiscing circumcisally around the base with valves splitting upward.
Seeds
generally 4-8 per locule, medium brown, ovoid-angular, mucilaginous when wet.
Nuclear gene
loci showing diploid PCR amplification patterns.
Figure 6.
Navarretia aeroides
.
A
Pressed specimen showing plant habit, scale bar = 1 cm (
Gowen 1303
)
B
Flowering head in the field, scale bar = 2 mm (
Johnson 14-142
)
C-F
Equivalent magnification, scale bar = 2mm
C, D
Pressed flowering head showing range of coloration in dried flowers (
Johnson 16-070, Gowen 1303
, respectively)
E, F
Fresh flowers showing range of coloration (
Johnson 16-063a, Johnson 15-065
, respectively). All photographs by L. A. Johnson and vouchers deposited at BRY.
Habitat, distribution, and phenology
Navarretia aeroides
prefers (reddish) clay soils in forest openings from 400-1350(-1900) meters elevation. Occurrences are widely scattered in the Sierra Nevada from Mariposa County, California in the south to Plumas County in the North, and in the Trinity mountains of the North Coast Range, California. This species flowers primarily June-July.
Conservation
status.
Many historical collections of this species are sufficiently general in their locality descriptions in areas now populated that our efforts to relocate them, compounded by recent drought years, have been unsuccessful. On the other hand, all but two of our collections were made serendipitously, in the course of looking for other species, suggesting our present knowledge of occurrences is incomplete. Following
IUCN (2012)
Red List version 3.1 criteria, this species is most accurately characterized as data deficient, though it may be Vulnerable based on the fragmented nature of a limited number of occurrences.
Etymology.
From the Latin
Navarretia aeroides
, like the sky or sky-blue, in reference to the typical color of the corolla.
Representative specimens examined
(
paratypes
)
.
UNITED STATES OF AMERICA
.
California
:
El Dorado County
,
Lake Valley
,
July 1908
,
Brandegee
s.n.
(UC; mixed collection with
N. divaricata
);
3 miles
east of
Camino
at
C.C.C. Camp Snowline
,
3400 ft
,
6 July 1943
,
Robbins
1247
(JEPS, UC);
0.1 mi
north of
Rescue
, along deer valley road,
1300 ft
,
30 June 1945
,
Robbins
2015
(UC);
3 miles
southeast of
Greenwood
,
Coloma Canyon
,
18 June 1957
,
Crampton
4233
(AHUC);
6.4 miles
east of
Diamond Springs
,
6 June 1960
,
Crampton
5546
(AHUC);
Sly
Park Vicinity. Park Creek Road
off of county road E16,
38.7493°N
,
120.4970°W
,
1207 m
,
8 July 2014
,
Johnson
14-142
(BRY, JEPS);
Mariposa County
,
Telegraph Hill Road
, ca.
7 miles
from
Hwy
140 via
E. Whitelock Road
,
37.5773°N
,
120.0038°W
,
809 m
,
9 June 2015
,
Johnson
15-005
(BRY, JEPS);
Nevada
County
,
Colfax
,
3 July 1882
,
Jones
3417.
(POM, scan);
Colfax
,
20-22 Jun 1912
,
Eastwood
498
(CAS, UC);
Rattlesnake Creek
,
5 miles
south of
Grass Valley
,
2000 ft
,
29 May 1926
,
Mason
3279
(UC);
Bed
of dried pond west of
Greenhorn Creek
, T
16N R9E S24,
3000 ft
,
27 August 1954
,
Raven
7980
(CAS);
Placer County
,
Nevada
City
,
Hospital Farm
,
Sierra
Nevada
Mtns
,
5000 ft
,
31 July 1915
,
Brainerd
&
Baird
236
(JEPS);
10 miles
west of
Forest Hill
,
15 June 1955
,
Crampton
2921
(AHUC);
Plumas County
,
2.5 miles
northeast of
Quincy Junction on
Mt Hough-Crystal Lake Road, T
24N R10E S4,
4200 ft
,
24 June 1981
,
Barbe
,
Fuller
, &
Howell
3181
(CHSC);
East of Quincy
, about
2.3 miles
along
Mt. H
road from its junction with
Quincy Jct Road
, at intersection with 25N14,
39.9747°N
,
120.8761°W
,
1321 m
,
12 June 2015
,
Johnson
15-065
(BRY, JEPS) and
14 July 2016
,
Johnson
16-087
(BRY, JEPS);
Trinity County
,
Hills
south above
Hayfork
,
between Kingsbury Rd. and Bridge Gulch Rd
,
25 June 2005
,
Gowen
462
;
East
side of
Hwy
3 south of
Clair Engle Lake
, ca
2.3 miles
south of
Tannery Gulch Road
,
40.8225°N
,
122.8887°W
,
947 m
,
16 July 2009
,
Johnson
09-109
(BRY);
About
7.3 miles
up
Wildwood Rd
(NF-3) from
Hwy
36,
40.4514°N
,
123.0649°W
,
1003 m
,
13 July 2016
,
Johnson
16-063a
(BRY);
South of Hayfork
about
3.3 miles
along
Kingsbury
road from jct with
Morgan Hill
road,
40.5074°N
,
123.1469°W
,
851 m
,
13 July 2016
,
Johnson
16-070
(BRY, JEPS);
Yuba County
, along margin of
New York
Flat Road
,
0.5 miles
north from jct with
Laporte
road (possible waif),
39.4812°N
,
121.2606°W
,
2255 ft
,
18 June 2004
,
Johnson
04-150
(BRY)
.
Notes.
Navarretia aeroides
are mephic when fresh. In 2015, the population first collected by Barbe, Fuller, & Howell in the mountains east of Quincy, California, was
found
to have been sprayed with 2,4-D (and blue indicator dye), along with
N. propinqua
, in an area designated for ORV use, perhaps having been mistaken for immature thistle. To date, occurrences in the Trinity Mountains can be distinguished morphologically (white corollas with magenta streaking in the throat and white pollen) from occurrences in the Sierra Nevada (blue to light blue corollas and blue pollen), yet we have resisted recognizing this difference at the subspecific level. As in any species with colored corollas, occasional white flowered individuals are observed in the Sierra Nevada among a sea of blue flowered individuals. The paratype of
Gilia atrata
M.E.Jones from Colfax, California [POM-75128 scan!] belongs here.
Navarretia aeroides
is a smaller-featured plant than either
N. vividior
or
N. modocensis
, though its corolla overlaps in size with
N. vividior
. The more conspicuously glandular inflorescence heads (in side-by-side comparisons) contrasts with all of the other species detailed here, and corolla coloration, fresh and dried, readily distinguishes this taxon from
N. divaricata
and
N. torreyella
.