Agapetus jocassee Morse

Etnier, David A., Parker, Charles R., John T. Baxter, Jr., Long, Todd M. & Drive, News Sentinel, 2010, A review of the genus Agapetus Curtis (Trichoptera: Glossosomatidae) in eastern and central North America, with description of 12 new species, Insecta Mundi 2010 (149), pp. 1-77 : 25-26

Agapetus jocassee Morse

Fig. 16a, 16b, 16c . Map 16

Agapetus jocassee Morse in Morse et al. 1989: 16

Type locality, Coley Creek at NC /SC border (Transylvania Co./Oconee Co.). ( NMNH)

Diagnosis. The very elongate inferior appendages (length> 4.5 times depth) separate A. jocassee from all North American Agapetus except A. baueri , A. flinti , A. iridis , and A. pinatus . Differs from all of these except A. baueri in having each inferior appendage with only 2 denticles (lacking terminal denticle), versus 3 denticles per appendage (terminal denticle present) in A. flinti , A. iridis , and A. pinatus . Differs from A. baueri (ventral view) in having a broad, serrate, trapezoidal ridge with the largest denticle at posterior end (single denticle in middle of narrow, triangular ridge along internal margin of inferior appendage in A. baueri ). In ventral view inferior appendages of A. jocassee have the subterminal denticle only 1 “denticle length” from the tip of the appendage (subterminal denticle 1.5 to 2.0 “denticle lengths” from tip of appendage in A. baueri ).

Description. Male. Length 4.6-6.2 mm (n = 29). Male genitalia: Lateral view ( Fig. 16a ), anterior margin of IX thickened, slightly concave near dorsal margin, then sloping down and forward at 40 o angle to midline, then convex and sloping down and back at 60 o angle to weakly sinuate ventral margin. Dorsal margin of IX a narrow bump, often concealed behind lateral shoulder; posteriodorsal margin of shoulder conceals basal 1/3-1/4 of preanal appendage. Dorsal margin of shoulder horizontal to sloping down and back at 25 o. Posterior margin of IX nearly vertical, convex to ventral margin. Exposed portion of preanal appendage 1/2 length of inferior appendage, deepest at base (concealed by IX), dorsal and ventral margins convergent to narrowest point at posterior margin of IX, then slightly divergent nearly to pointed tip, maximum visible depth = 0.1 times visible length, 11 or 12 long dorsal setae along distal 3/4. Segment X membranous except for sclerotized ventral margin, sclerotized portion thickest on basal 1/3, distal 2/3 with sclerotized area 1/2 as thick as on basal 1/3 (= depth of preanal appendage), and forming 130 o angle with basal 1/3. Distally, X extends past inferior appendage tip; each arm terminating in a pair of sharp, dark denticles. Outer denticle a straight continuation of dorsal edge of sclerotized area; more medial denticle dorsal to other denticle, tip decurved, and not extending as far posteriad as lateral denticle. Inferior appendage 0.8 times as long as X, length = 5 ( Craft and Morse 1997) to 6 times depth; sclerotized dorsal margin with slight concavity at base, then convex to rounded tip. Ventral margin nearly straight, slightly concave near tip; mid-lateral subterminal black denticle visible as a dark dot. Lateral margin of inferior appendage visible as dark horizontal line near mid-depth, especially in middle 1/3-1/4 of appendage.

Dorsal view ( Fig. 16b ). Anterior and posterior margins of IX deeply concave, nearly in contact at midline. Preanal appendages with straight to slightly concave outer margin, inner margin convex, more so at tip, to form sharp point. Sclerotized lateral arms of X converge from base to 1/3 length, then slightly divergent (5 o from body axis), then more divergent near swollen, denticle-bearing tips. Outer denticle a continuation of lateral margin of ventral arm, occasionally bifid; inner denticle a continuation of inner margin; both denticles parallel, diverging from body axis at 45 o. Segment X with dorsal area membranous from base of inner denticle nearly to posterior margin of IX, sides of area diverging anteriad. Inferior appendages with both pairs of denticles visible.

Ventral view ( Fig. 16c ). Anterior margin of IX concave, posterior margin poorly differentiated, forming 130 o angle between inferior appendage bases, area between outer inferior appendage bases depigmented, separated from anterior portion of IX by a conspicuous row of setae. Inferior appendages with outer margin sinuate, concave near base, convex distally. Inner margin of inferior appendages in contact at base, then divergent to serrate trapezoidal shelf, then slightly concave to subterminal denticle. Each inferior appendage with largest denticle on serrate ridge near posterior end of ridge; a single (rarely two) subterminal denticle on inner margin 1 “denticle-length” from end of inferior appendage.

Larva. Essentially identical to that of A. baueri , with the following characters possibly differing between the two species: Frontoclypeus lacking transverse row of darker muscle scars. Gena lacking paler posterior 1/3. Prosternal sclerites with outer edge 2 times length of inner edge. Sclerites on IX and X darker than head and thoracic sclerites. The larva and pupa were described by Craft and Morse (1997).

Emergence dates. 26 April-21 July, plus mature male pupae 12 and 27 September.

Distribution. GA Gilmer (3), Rabun. NC Buncombe, Cherokee (4), Clay, Graham (2), Haywood (2), Henderson, Jackson (3), Macon, Swain (5), Transylvania (15). SC Oconee (2). TN Monroe, Polk.

Figures

Figure 16-18. Agapetus spp. male genitalia. 16) Agapetus jocassee Morse. 16a, lateral view; 16b, dorsal view; 16c, ventral view of IX and inferior appendages. 17) Agapetus kirchneri Parker, Etnier, and Baxter. 17a, lateral view; 17b, dorsal view; 17c, ventral view of IX and inferior appendages. 18) Agapetus medicus Ross. 18a, lateral view; 18b, dorsal view; 18c, ventral view of IX and inferior appendages.