Polycentropus aileenae Orfinger & Moulton, 2021

Orfinger, Alexander B. & Moulton, John K., 2021, Polycentropus aileenae n. sp. (Trichoptera: Polycentropodidae), a caddisfly species from the eastern Nearctic, with new state records for members of the Polycentropus confusus Species Group, Zootaxa 4996 (2), pp. 353-362: 355-359

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Polycentropus aileenae Orfinger & Moulton

n. sp.

Polycentropus aileenae Orfinger & Moulton   , n. sp.

Figures 1 View FIGURE 1 , 2A–2E View FIGURE 2 , 3A, 3B View FIGURE 3 .

Polycentropus carlsoni Morse 1971   ( Moulton 2007: 209–210, nec Morse 1971)

Description. General Structure ( Fig. 1 View FIGURE 1 ). Length of male 6.1–7.0 mm (n = 5). Length of female 7.5–8.75 mm (n = 2). General habitus typical of males of the Polycentropus confusus   Species Group. In ethanol, eyes brown to purple and glazed; body color various shades of brown, with subtle spots of lighter brown and yellow forming irrorate pattern on front wings; hind wings uniformly brown; legs tan to pale yellow.

Male Genitalia ( Figs 2A–2E View FIGURE 2 ): Abdominal segment VIII annular. Segment IX tergum fused with segment X, membranous, caudally extended as short, horn-like projection. Segment IX sternum ovoid in lateral view, posterior margin slightly sinuous. Intermediate appendages positioned beneath terga IX+X, distally extending beyond tergum X, apices each bearing 3 small setae; in lateral view curved slightly ventrad; in dorsal view apices proximate, subparallel. Bodies of preanal appendages (pre.app.) slightly produced, each with small posteroventral lobate process; in lateral view dorsal process long, whip-like, curved ventrad; in dorsal view slender, elongate, strongly inflected and converging apically. Inferior appendages in lateral view each with ventral portion gradually tapered, extended posterad slightly beyond intermediate appendages, ventral margin nearly straight; in ventral view, basal half wide, distal half abruptly narrowed, inner margin curved outward; dorsobasal process in lateral view erect, with long neck terminating in short, rounded head projecting downward, in ventral view obscured completely by ventral portion of clasper. Phallus in lateral view curved ventrad, apical section rectangular, dorsum of apex slightly recurvate (subtle in some specimens), spinules absent, phallic sclerite moderately elongate.

Female Genitalia ( Figs 3A, 3B View FIGURE 3 ): Venter VIII in ventral view with ventral plates (v.pl.) narrow, tapering apically, convergent, and rounded at posterior apices in ventral view, covered in setae; in lateral view similar but each terminating in more-acute posterior apex; posterior apex of external parts of gonopods VIII (p.ap.e.gon.VIII) with posterior margin slightly triangular and rounded mesally in ventral view; in lateral view extending beyond ventral plates in rounded process (e.gon.VIII); internal parts of gonopods VIII (i.gon.VIII) in ventral view visible through venter VIII, appearing longitudinally wrinkled, darker than surrounding tissue, parallel, semi-elliptical with rounded posterior apices distinctly anterior of apices of ventral plates, anterior ends oblique, extending to sclerotized external part of gonopods VIII at basal third of ventral plates; in ventral view anterior part of genital chamber (g.ch.a) sclerotized, semicircular; processus spermathecae (pr.sp.) subovoid with central elevation bearing opening of ductus spermathecae (op.dt.sp.).

Pupa and larva: Unknown

Eggs: In ethanol, white, smooth in appearance, each roughly spherical, 0.22 mm to 0.30 mm in diameter; extruded linearly in a moniliform chain.

Diagnosis. The male genitalia of Polycentropus aileenae   are most similar to those of males of P. blicklei Ross & Yamamoto 1965   , P. carlsoni   , P. carolinensis Banks 1905   , and P. elarus Ross 1944   . Polycentropus aileenae   can be separated from the above-mentioned species by the strongly inflected apices of the dorsal processes of the preanal appendages in dorsal view versus straighter dorsal processes in the other species, and the slightly recurved dorsum of the apex of the phallus in lateral view absent in other species. From P. blicklei   , P. carlsoni   , and P. carolinensis   , the new species differs in the shape of the ventral portion of each inferior appendage in which the lateral and ventral margins are nearly straight versus moderately curved in P. carolinensis   and P. carlsoni   , and by the long rectangular basal half that in ventral view narrows abruptly from middle to apex versus gradual narrowing along length in P. blicklei   . Polycentropus aileenae   differs in the shallower and more rounded body of each preanal appendage versus the more broadly produced and more acutely terminated body of each preanal appendage in P. blicklei   , P. carolinensis   , and P. elarus   .

Female genitalia of Polycentropus aileenae   are most similar to those of P. blicklei   , for which only subtle differences are apparent in separating females of the two species. The internal parts of gonopods VIII are rounded at the posterior apices versus the sharper posterior apices resulting in each having a blade-like appearance in P. blicklei   , and the internal parts of gonopods VIII are parallel in P. aileenae   versus subparallel in P. blicklei   . In addition, the processus spermathecae is slightly more rounded in P. aileenae   relative to the more ovoid shape in P. blicklei   .

Material Examined. Holotype: USA. Tennessee: Knox County, Fowler Spring Branch, first-order tributary to Beaver Creek , Bell Campground Road , 0.3 km N of jct. with W. Brushy Valley Drive, UV Light Trap , 277 m elevation, [N36°02’56.2”, W84°04’07.6”], A. Orfinger and A. Perilla coll., 6-vi-2020, 1 male (USNMENT01445176). GoogleMaps  

Allotype: USA, Tennessee: Same data as for holotype except J.K. Moulton coll., 9-x-2005, 1 female ( FAMU). GoogleMaps  

Paratypes: USA, Tennessee: Same data as for holotype except J.K. Moulton coll., 9-x-2005, 1 male ( USN- MENT01445177). Same data except 18-xi-2006, 1 male ( CUAC000107331 View Materials ). Jefferson County, Dumplin Creek at Hebron Church Road , UV GoogleMaps   Light Trap, 337 m elevation, [N36°03’38.8”, W83°27’20.6”], J.K. Moulton coll., 30-v-2006, 5 males ( INHS Insect Collection 923903). Same data except 9-viii-2006, 1 male, ( FAMU). Jefferson County, Tributary of Holston River at Good Hope Church Road , UV GoogleMaps   Light Trap, 280 m elevation, [N36°09’58.3”, W83°33’49.7”], G. Curler coll., 28-v-2005, 1 male ( ROME187177 View Materials ). Jefferson County, Dumplin Creek at old TN Rt. 92, UV GoogleMaps   Light Trap, [N36°03’38.8”, W83°27’20.6”], J.K. Moulton coll., 23-v-2005, 1 female ( CUAC000107332 View Materials ) GoogleMaps   .

Non-Type Material: Canada, Nova Scotia: Cape Breton Highlands National Park, Clyburn Valley Road , near golf course, Malaise Trap, 21 m a.s.l., [N46°39’19.1”, W60°25’42.6”], CBHNP GoogleMaps   Staff coll., 12/VII/2013, 1 male ( BIOUG09994 View Materials -A03)   . USA. Tennessee: Jefferson County, Dumplin Creek at old TN Rt. 92, UV   Light Trap , [N36°03’38.8”, W83°27’20.6”], J.K. Moulton coll., 26-v-2006, 5 males ( UTK) GoogleMaps   .


2A 2B ph. sc. inf. app.


2C 2E

3A 3B

Comparative Material Examined. The list of comparative material examined ( Table 1) represents the remaining members of the Polycentropus confusus   Species Group, with the exception of P. vernus   and the female of P. neiswanderi   for which the original descriptions and illustrations were used. Type material was examined when available, for most species, and all original descriptions were consulted. The number of females examined is indicated only for those species from which females are known.

Etymology. The specific epithet honors Aileen Perilla in appreciation of her continued support of the first author, her enthusiastic and skillful assistance during field work, and her shared appreciation of the imperiled stream habitats in which these animals occur.


Departamento de Biologia de la Universidad del Valle


Illinois Natural History Survey














Polycentropus aileenae Orfinger & Moulton

Orfinger, Alexander B. & Moulton, John K. 2021

Polycentropus carlsoni

Moulton, J. K. 2007: 209