A review of the genus Agapetus Curtis (Trichoptera: Glossosomatidae) in eastern and central North America, with description of 12 new species
Author
Etnier, David A.
Author
Parker, Charles R.
Author
John T. Baxter, Jr.
Author
Long, Todd M.
Author
Drive, News Sentinel
text
Insecta Mundi
2010
2010-11-29
2010
149
1
77
journal article
10.5281/zenodo.5353074
1942-1354
5353074
Agapetus harrisi
Etnier, Parker, and Baxter
new species
Fig. 10a, 10b, 10c
. Map 10
Type material.
Holotype
, male,
MMT
pupa,
EX
UT 1.607
,
Chandler Branch
0.6 rd mi n of jct. co rd 593 on AL 79,
34.4680
o
N
,
86.2270
o
W
,
Marshall Co.
, AL
,
26 April 2000
, preserved 23
May, DA
Etnier. (
NMNH
)
Allotype
,
MMT
female,
5.4 mm
, collected with holotype, preserved 8 May.(
NMNH
)
Paratopotypes, all
EX
UT 1.607
and collected with holotype.
CUAC
,
MMT
male pupa,
MMT
female pupa, preserved 23 May,
1 larva
;
INHS
,
MMT
female pupa preserved 23 May,
1 larva
;
ROME
,
MMT
male pupa,
MMT
female pupa, preserved 11 May,
1 larva
;
SCHC
,
MMT
male pupa, preserved 23 May;
UMSP
,
MMT
male pupa,
MMT
female pupa, preserved 23 May,
1 larva
;
2
MMT
female pupae (preserved 21 April), and 5 early pupae remain in
UT 1.607
.
Additional
paratypes
, AL 79 at co rd 377, 5.0 rd mi s of jct. AL 279,
Jackson Co.
, AL,
10 April 1999
-
CASC
;
MMT
male pupa preserved 3
May
,
MMT
female preserved 26
April
,
1 larva
;
INHS
,
MMT
male pupa, preserved 6
May
;
5 larvae
, 2 early pupae;
5
MMT
male pupae, 11
MMT
male/female pupae, remain in
UT 1.457
;
UT 1.1034
, se side of co rd 67, 50 m ne of powerline, 2.3 rd mi ne of co rd
38 in
Langston
,
Jackson Co.
, AL,
27 April 2006
,
1 larvae
1 prepupa, 1
MMT
male, 3
MMT
female, emerged 30 April-1
June
.
Diagnosis
. Only two other species (
A. ibis
,
A. meridionalis
) of eastern and central North American
Agapetus
have the end of the ventral arms of X abruptly down-curved and pointed. Differs from both of these in having tip of inferior appendage with a deep posterioventral emargination (versus smoothly rounded). Also similar to
A. tomus
,
in which tip of inferior appendage is weakly and symmetrically emarginate, and the ventral projection of the ventral arms of X is broadly rounded rather than pointed.
Description
.
Male
. Length
5.4-6.1 mm
(n = 2). Male genitalia: Lateral view
(
Fig. 10a
), anterior margin of IX thickened, concave and sloped down and forward at 65
o
to midline, then down and back at 75
o
to convex ventral margin; dorsal margin horizontal, slightly depressed in middle, length = 3/4 length of ventral margin. Posterior margin of IX nearly vertical, slightly concave on dorsal 1/2, produced posteriad at mid-depth, convex to ventral margin. Preanal appendage ovoid, 1/3 length of X, length = 1.5 times depth, about 10 dorsal setae. Length of X = 3/4 inferior appendage length, moderately sclerotized dorsal margin converges with ventral arm toward tip; ventral arm slender at base, gradually broader distad, shaped like hockey stick with tip (acutely pointed, occasionally bifid) directed posterioventrad at 45
o
, “heel” expanded and pointed dorsad to merge with dorsal margin. Inferior appendage length = 1.6-2.0 times depth; dorsal and ventral margins slightly divergent, dorsal margin straight; ventral margin straight basad, convex distad, and continuing posteriad as finger-like extension; posterior margin angles down and forward at 65
o
from rounded posteriodorsal corner to base of finger-like ventral projection.
Dorsal view (
Fig. 10b
). Anterior margin of IX deeply concave, with median thickened ridge on anterior 1/2; posterior margin straight, moderately differentiated from X. Each preanal appendage with convex margins, diverging from body axis at 25
o
. Lateral margins of X straight, diverging from body axis at 10
o
, posterior margin in-curved to posterioventral points; inner margins joined near base, V-shaped, meeting at 30
o
angle, membranous area between lateral plates of X has V-shaped anterior and posterior border. Ventral arms of X dark on inner margin, mostly concealed by dorsal sclerotized area.
Ventral view (
Fig. 10c
). Anterior margin of IX thickened, nearly straight; posterior margin with obtuse (120
o
) angular projection between bases of inferior appendages; triangular depigmented area often apparent at posterior margin. Outer margin of inferior appendages with bulbous base, slightly concave middle 2/3, tips slightly in-curved; inner margin nearly straight to transverse denticle at tip; posterior emargination U- or V-shaped, extending forward 0.2 times length of appendage.
Larva
. Head and notal sclerites glossy brown, darker than other sclerites, which are straw-yellow, with darker brown sutures and edges typical for genus. Sclerites of MMTs faintly marked, frontoclypeus with area behind arc from mid-lateral corners darker than anterior 3/4 of sclerite; two weak, dark muscle scars along line between lateral corners, each 3/4 distance from corner to midline; single weak, transverse muscle scar at midline just anterior to darkened posterior area. Genae with large, rectangular, pale eye spot; two irregular rows of pale, rounded to vertically elongate muscle scars angle down and back from eye area at 15-20
o
from horizontal, the upper row extending halfway from posterior border to pale eye area.
Emergence dates
. 26 April-1 June.
Distribution
.
AL
Jackson (2), Marshall.
Discussion
. The 1999 Jackson County locality is tiny, with limited
Agapetus
substrate, and with discarded oil cans and other debris in the creek. The species is abundant at the
type
locality, which appears to be reasonably stable. In
April 2006
we found a third population in a tiny southeastern tributary to Guntersville Reservoir, which is protected by TVA ownership.
Agapetus harrisi
appears to be one of the most geographically restricted
Agapetus
of eastern North America. We suggest that searches for additional populations be conducted, especially at the head ends of several embayments on the southeast side of Guntersville Reservoir south of Scottsboro, and on the northwest side of the reservoir north of Scottsboro. If these searches fail to yield additional populations, it should be considered for
Alabama
and Federal protected species status.
Etymology
. Named in honor of Steven C. Harris, friend, colleague, trichopterist, and superb student of the microcaddisflies (family
Hydroptilidae
).