Corresponding authors: M. Alma Solis (
Academic editor: M. Nuss
The genus
Solis MA, Metz MA (2016) An illustrated guide to the identification of the known species of
The genus
Lateral habitus and male genitalia of
Over eighty species names have been associated with
Type specimens of Natural History Museum National Museum of Natural History Carnegie Museum of Natural History
Genitalia preparation for identification (
To remove the female genitalia, the abdomen should be cut laterally the entire length and then around the abdomen between segments VI and VII. The female may have more tissues surrounding the genitalia and must be cleaned with a brush carefully. The corpus bursae varies in length and width, so it is better to examine it when it is still turgid. If slide mounted, care should be taken to not fold, tear or collapse the corpus bursae. The female apparatus is usually membranous, but may not need staining. If staining is required to see structures use a saturated solution of chlorazol black for only a few seconds. The female can then be identified using the key to females below. The genitalia can then be stored in genitalia vials with glycerin if available, or in 70% alcohol that may harden, but will also preserve, the genitalia as vouchers. Two videos are also available to view dissection techniques in great detail (
Male genitalia:
Terminology within the keys and the major structures of the male genitalia are as follows (Figs
The female genitalia (Figs
The adapted key below using external and tympanal characters from
(adapted from
1 | Praecinctorium absent; tympanal case “closed” medially and open anteriorly only; tympanum and conjunctiva in the same plane |
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– | Praecinctorium present; tympanal case “open” anteromedially; tympanum meeting conjunctiva at a distinct angle |
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2 | Chaetosema absent; forewing with distal part of CuP developed as a tubular vein; proboscis present, but reduced; tympanal cases reduced and widely separated; praecinctorium reduced | other |
– | Chaetosema present; forewing with CuP absent, not developed as a tubular vein; proboscis usually present and tympanal organs almost always normally developed |
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3 | R2 of forewing at least closely apposed to and usually stalked with R3+4; labial palpus usually upturned, basal segment often longer than second segment; wings mostly with conspicuous pattern of transverse bands on a pale ground; larvae aquatic, rarely in damp terrestrial habitats | other |
– | R2 of forewing well separated from R3+4; labial palpus often porrect, basal segment much shorter than second segment; wings usually without conspicuous pattern of transverse bands on a pale ground; larvae usually terrestrial, sometimes stem borers in aquatic graminaceous plants |
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4 | Forewing usually with weakly raised patches of black scales; cubitus of hindwing usually not pectinated with hairlike scales; lateral arms of tegumen of male genitalia about as long as uncus, little tapered ventrally; uncus of moderate length, pyriform, hoodshaped or bilobed, not obviously decurved from base to tip; gnathos with median element spikelike, sword-shaped, or digitate, straight or decurved, rarely reduced; uncus and gnathos not forming a jawlike structure, and not widely separated dorsad from valvae; valva sometimes with a ventral process but, except in |
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– | Forewing without raised patches of black scales; cubitus of hindwing usually pectinated with hairlike scales, lateral arms of tegumen of male genitalia much longer than uncus or narrowed ventrally, usually both; uncus usually long, acuminate, and more or less decurved from base to tip; gnathos with lateral arms articulating at base of uncus, medial element various in shape, often rodlike or forming a dorsally directed hook; uncus and gnathos forming a jawlike structure, widely separated dorsad from valvae; valva often with strong costal process or medial armature; larvae mostly feeding at bases, roots, stems of grasses ( |
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In the
Note: Described from a series of 7 specimens from Venezuela and Brazil.
Note: This appears to be a variable species based on the number of specimens available and barring numerous dissections. Despite differences in size and coloration, the male genitalia are consistent throughout with the same morphology for the uncus and gnathos, lateral process of the tegumen, and costal processes. The females, however, are not consistent. In the
Note: Only known from two specimens, the female holotype in the
Note: Known only from male specimens. The single female specimen noted by
[
1 | Uncus broad at apex, paddle-shaped ( |
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1’ | Uncus triangular, narrowing at apex, beaklike |
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2 (1) | Tegumen with crenulate, lateral lobes; uncus stiff, extended ventrolaterally, but not bilobed (Fig. |
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2’ | Tegumen at most carinate laterally, lacking lobes; uncus less sclerotized and bilobed (Figs |
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3 (2’) | Juxta with four lateral projections, two central, long, and two lateral, short (Fig. |
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3’ | Juxta with three projections, two lateral, long, and one central, shorter, (Fig. |
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4 (1’) | Juxta with three projections, two lateral and one central ( |
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4’ | Juxta with two lateral projections |
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5 (4) | Central projection of juxta more than five times longer than wide (Fig. |
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5’ | Central projection of juxta less than three times longer than wide (Figs |
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6 (5) | Medial portion of basal costal lobe on valva crenulate almost as broad as long (Fig. |
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6’ | Medial portion of basal costal lobe on valva smooth, slender, acutely pointed (Fig. |
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7 (4’) | Valva costal margin with narrow, accessory process (Fig. |
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7’ | Valva costal margin lacking narrow accessory process, basal costal lobe present or absent |
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8 (7) | Valva accessory process on costal margin curved, face of juxta arms with denticles (Fig. |
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8’ | Valva accessory process on costal margin straight, juxta arms with denticles only on posterior edge (Fig. |
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9 (7’) | Apex of juxta arms bidentate, with two distinct points ( |
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9’ | Apex of juxta arms with a single point or rounded with a small, subapical tooth, but never bidentate |
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10 (9) | Apex of juxta arms cylindrical, apical teeth subequal in size, clawlike (Fig. |
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10’ | Apex of juxta arms flat, apex pointed with smaller subapical tooth (Figs |
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11 (10’) | Apex of lateral juxta arms spatulate, gnathos with large, pointed process in middle (Fig. |
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11’ | Apex of lateral juxta arms attenuate, gnathos without process (Fig. |
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12 (12’) | Apex of gnathos bluntly rounded and denticulate, apex of uncus pointed (Fig. |
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12’ | Apex of gnathos and uncus spatulate (Fig. |
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13 (9’) | Teeth on gnathos 6× longer than wide or longer, like setae (Figs |
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13’ | Teeth on gnathos no more than 4×longer than wide, short like serrations on a butter knife, or completely absent |
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14 (13) | Uncus drastically narrowing before apex, then apex slightly capitate and cleft, lateral edges of uncus rough; gnathos recurving back on itself noticeably (Fig. |
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14’ | Uncus slightly narrowing towards apex, but not noticeably capitate, apex rounded or pointed, lateral edges smooth or carinate; gnathos slightly hooked, but not recurving back towards base (Fig. |
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15 (14’) | Ventrolateral edges of uncus medially expanded into wide blades, apex broadly spatulate (Fig. |
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15’ | Ventrolateral edges of uncus medially carinate, but not expanded, apex flat, but not broadly spatulate (Fig. |
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16 (13’) | Lateral edge of tegumen without lobelike process (lateral lobes of D. & H., 1927) ( |
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16’ | Lateral edge of tegumen with lobelike process, sometimes small and hard to see (as in |
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17 (16) | Juxta constricted laterally before base of juxta arms, juxta arms emerging more medially (Fig. |
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17’ | Juxta evenly rounded to base of juxta arms, juxta arms emerging more laterally |
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18 (17’) | Valva costal margin significantly extended posteriorly, apically of basal costal lobe, basal costal lobe present (Figs |
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18’ | Valva costal margin not significantly extended posteriorly, apically of basal costal lobe, basal costal lobe absent or present (Fig. |
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19 (18) | Apex of basal costal lobe of valva sharply pointed (Fig. |
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19’ | Apex of basal costal lobe of valva evenly rounded (Fig. |
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20 (18’) | Apex of juxta arms rounded with subapical tooth (Fig. |
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20’ | Apex of juxta arms pointed (Figs |
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21 (20’) | Gnathos thin and cylindrical (Fig. |
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21’ | Gnathos flattened and beaklike (Fig. |
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22 (21’) | Gnathos with a pronounced mound of teeth subapically (Fig. |
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22’ | Gnathos with teeth, but not on a distinct, subapical mound |
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23 (22’) | Valva without basal costal extension (Fig. |
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23’ | Valva with bluntly pointed basal costal extension, but no real lobe (Figs |
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24 (23’) | Gnathos in lateral view more-or-less straight from base to tip, dorsal surface slightly undulate, but not arcuate, only tip with slight hook; tegumen in lateral view larger at the base than at the point of articulation with uncus/gnathos; brush of setae at tip of valva dense and long, length more than twice width of valva where brush emerges from valva (Fig. |
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24’ | Gnathos in lateral view arcuate, middle of dorsal surface “lower” than base and tip; tegumen in lateral view more-or-less equal in width throughout length; brush of setae at tip of valva only slightly more conspicuous than rest of setae on valva, length subequal to width of valva where brush emerges from valva (Fig. |
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25 (16’) | Small species, juxta arms acutely pointed apically with no subapical tooth (Fig. |
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25’ | Large species, juxta arms rounded apically, subapical tooth absent or present ( |
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26 (25’) | Lateral lobes of tegumen conspicuous, at least as long as wide at base (Fig. |
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26’ | Lateral lobes of tegumen obscure, no more than half as long as wide at base (Fig. |
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27 (25’) | Lateral lobe of tegumen square, either with corners sharp or rounded (Figs |
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27’ | Lateral lobe of tegumen rounded or pointed |
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28 (27) | Lateral lobe of tegumen square with rounded corners (Fig. |
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28’ | Lateral lobe of tegumen square with sharp corners (Fig. |
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29 (27’) | Lateral lobe of tegumen broadly rounded, basal width 2/3 length of tegumen (Fig. |
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29’ | Lateral lobe of tegumen less broad, basal width at most 1/2 length of tegument |
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30 (29’) | Valva basal costal lobe triangular, not significantly produced, lacking crenulations, carinae, or denticulation, setose only (Fig. |
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30’ | Valva basal costal lobe globular, at least partially, significantly produced, with at least some crenulation, carinae, or denticulation |
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31 (30’) | Valva basal costal lobe weakly crenulate dorsally (Fig. |
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31’ | Valva basal costal lobe strongly crenulate, carinate and/or denticulate |
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32 (31’) | Lateral lobe of tegumen sharply pointed, apex flattened anteroposteriorly (Figs |
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32’ | Lateral lobe of tegumen bluntly pointed or rounded |
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33 (32) | Uncus with ventrolateral, carinate margin constricting sharply and is not carinate just before apex of uncus, thus making apex slightly spatulate; basal costal lobe of valva capitate, posterior surface evenly rounded and lacking a depression; transition between basal costal lobe and following section of costa smooth, not notched (Fig. |
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33’ | Uncus with a ventrolateral, carinate margin that is complete, not tapered before reaching apex; basal costal lobe of valva protruding posteriorly only, not widened laterally at apex, with small depression in posterior surface; with roughened notch between base of basal costal lobe and following section of costa (Fig. |
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34 (32’) | Valva basal costal lobe base with basal and apical widths subequal, entire lobe wider than long (Fig. |
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34’ | Valva basal costal lobe narrower at base than apex, essentially capitate (Figs |
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35 (34’) | Lateral lobe of tegumen clearly ovate (Fig. |
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35’ | Lateral lobe of tegumen bluntly pointed (Figs |
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36 (35) | Lateral lobe of tegumen as long as wide (Fig. |
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36’ | Lateral lobe of tegumen longer than wide (Fig. |
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37 (35’) | Anterior edge of lateral lobe of tegumen angled, perpendicular to tegumen at base, then turning posteroventrally (Fig. |
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37’ | Anterior edge of lateral lobe of tegumen straight or arcuate, but not angled |
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38 (37’) | Anterior edge of lateral lobe of tegumen straight, denticulation on valva basal costal lobe large and densely packed on lobe (Fig. |
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38’ | Anterior edge of lateral lobe of tegumen arcuate, denticulation on valva basal costal lobe large or small, but not densely packed on lobe (Figs |
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39 (38’) | Denticulation of valva basal costal lobe small, lobe essentially not darkened more than rest of cuticle as a result of denticulation (Fig. |
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39’ | Denticulation of valva basal costal lobe large, lobe darkened more than rest of cuticle as a result of denticulation (Fig. |
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[The female is unknown for the following species and therefore not included in the key below:
1 | Corpus bursae with darkly sclerotized, teethlike spines or flattened plates (Figs |
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1’ | Corpus bursae completely membranous, at most with areas of darkened cuticle |
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2 (1) | Lamella antevaginalis hardened and darkened, appearing as a medially-bisected plate that protrudes posteriorly over the genital opening; corpus bursae with a ring of sclerotized flattened plates (Fig. |
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2’ | Lamella antevaginalis membranous, possibly sclerotized as much as sternites, but not dark or protruding over the genital opening; corpus bursae with opposite patches of sclerotized teethlike spines (Fig. |
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3 (1’) | Sternite VIII with a broad, transverse “pocket” mostly concealing ostium bursae; lamella antevaginalis composed of a pair of hardened, posteriorly projecting extensions that may cover the genital opening or surround it laterally; lamella postvaginalis with lateral areas of wrinkled and/or densely setose cuticle contrasting strikingly with medial area that is smooth and glabrous; or if lamella postvaginalis immediately posterad ostium bursae smooth and concave then with a pair of densely setose transverse ridges posterad concavity that project ventrally ( |
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3’ | Sternite VIII with ventral surface continuous with ostium and membranous never forming a transverse pocket concealing ostium; or if lamella antevaginalis and/or lamella postvaginalis varously sclerotized and ostium concealed then without contrasting lateral areas of roughened or densely setose cuticle and a pair of densely setose transverse ridges posterad |
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4 (3) | Corpus bursae more than 5× longer than wide; corpus bursae shape cylindrical, more or less parallel sided (Fig. |
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4’ | Length of corpus bursae variable, but if longer than wide then less than 5× longer than wide; corpus bursae shape variable, but usually irregular to ovate |
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5 (4’) | Lateral, wrinkled and densely setose cuticle of lamella postvaginalis continuous with and continuing laterally along posterior margin of sternite VIII, not forming subcircular patches (Fig. |
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5’ | Lateral, wrinkled and/or densely setose cuticle of lamella postvaginalis not reaching posterior margin of sternite VIII, or if approximate to posterior margin forming distinct subcircular patches contrasting with the rest of sternite VIII cuticle (Fig. |
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6 (5’) | Lamella postvaginalis lacking a distinct pair of transverse ridges posterad, cuticle wrinkled or densely setose, but solitary set of transverse ridges undetectable (Figs |
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6’ | Lamella postvaginalis with a distinct pair of transverse ridges posterad, ridges distinct from surrounding cuticle |
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7 (6) | Corpus bursae only slightly longer than wide, not extending or barely extending beyond anterior margin of sternite VIII (Fig. |
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7’ | Corpus bursae length at least 2X greater than width, extending well beyond anterior margin of sternite VIII |
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8 (7’) | Ductus bursae with longitudinal grooves, uniformly darkened throughout length from ostium to corpus bursae; corpus bursae with pair of acuminate strips of darker cuticle descending from ductus bursae (Figs |
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8’ | Ductus bursae more or less smooth, lightly darkened except for contrasting colliculum at junction with corpus bursae that is considerably darker; corpus bursae without any darkened areas at base, completely membranous (Fig. |
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9 (6’) | Corpus bursae length 4× greater than width, long and narrow with lateral expansions near middle no wider than width of corpus; posteriorly projecting extensions of lamella antevaginalis reduced, mostly membranous (Fig. |
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9’ | Corpus bursae length 2× greater than width or less, irregularly shaped or ovate, width at middle appearing to contribute to overall shape of corpus rather than as lateral expansions; posteriorly projecting extensions of lamella antevaginalis enlarged and conspicuous, middle membranous area much narrower |
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10 (9’) | Densely setose, ventrally projecting transverse ridges encompassing posterior half of lamella postvaginalis, flat anterad only, forming broad pillow shapes in posterior half of lamella postvaginalis (Fig. |
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10’ | Densely setose, ventrally projecting transverse ridges forming a narrow band in lamella postvaginalis, flat both anterad and posterad, forming an elevated crest at posterior margin of lamella postvaginalis (Fig. |
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11 (10’) | Posterior margin of hardened, posteriorly projecting extensions of lamella antevaginalis smooth and broadly arcuate, forming an almost semicircular arc from medial to lateral edge (Fig. |
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11’ | Posterior margin of hardened, posteriorly projecting extensions of lamella antevaginalis irregularly shaped with at least one substantial notch or indentation, bluntly pointed, forming a triangle (Figs |
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12 (3’) | Lamella antevaginalis and/or lamella postvaginalis variously sclerotized and adorned with texture markedly different than remaining cuticle of sternite VIII (Figs |
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12’ | Lamella antevaginalis and/or lamella postvaginalis unadorned, cuticle around ostium not significantly dissimilar to cuticle of rest of sternite VIII |
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13 (12) | Lamella antevaginalis with rugose cuticle continuous from sternite VIII to hardened, posteriorly projecting, cylindrical extensions around rim of ostium bursae that are bisected medially by a hardened slot (Fig. |
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13’ | Lamella antevaginalis with a raised ring of semicircular cuticle separating sternite VIII cuticle from margin of ostium bursae by a semimembranous depression |
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14 (13’) | Raised circular cuticle of lamella antevaginalis darkened around entire edge, medially as dark as laterally; lamella antevaginalis laterally with denser/larger setal sockets, but not rugose; rim of ostium bursae and beginning of antrum irregularly notched and grooved; lamella postvaginalis smooth medially, membranous (Fig. |
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14’ | Raised circular cuticle of lamella antevaginalis not darkened medially, noticeably darker on lateral edges; lamella antevaginalis laterally with rugose cuticle in addition to more densely spaced setal sockets; rim of ostium bursae with a single medial notch; lamella postvaginalis medially with semicircular ridges resembling a thumbprint (Fig. |
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15 (12’) | Antrum with heavy sclerotization in the shape of a yoke, narrower at dorsal margin of ostium bursae, widening laterally and descending down antrum, lateral edges folded inward forming a trough (Fig. |
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15’ | Antrum variously sclerotized, but sclerotization not shaped like a yoke or lateral edges folded into a trough |
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16 (15’) | Antrum and ductus bursae only lightly sclerotized or not at all, colliculum not evident; union of ductus bursae and corpus bursae smooth, not constricted, so that beginning of corpus is indistinct (Fig. |
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16’ | Antrum and ductus bursae with some sclerotization and colliculum usually present; if sclerotization of membrane light or indistinct then terminus of ductus bursae and beginning of corpus bursae always obvious |
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17 (16’) | Terminal end of ductus bursae with a spherical, membranous expansion that is 2× wider than ductus bursae before pinching to opening of corpus bursae (Fig. |
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17’ | Ductus bursae with varying shapes and widths, but never with a large, spherical expansion before the opening of the corpus bursae |
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18 (17’) | Corpus bursae medially wider due to presence of shallow lateral pockets on each side about midway, not simply oval-shaped |
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18’ | Corpus bursae oval shaped, without shallow lateral pockets on each side |
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19 (18) | Ostium bursae and antrum equal in width, but ductus bursae narrower forming a constriction before corpus bursae (Fig. |
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19’ | Ostium bursae, antrum, and ductus bursae subequal in width, constriction if any before corpus bursae subtle (Fig. |
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20 (18’) | Lamella postvaginalis with long setae near ostium bursae (Fig. |
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20’ | Lamella postvaginalis without long setae near ostium bursae |
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21 (20’) | Corpus bursae length at least 4× width, long and narrow, more cylindrical than oval |
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21’ | Corpus bursae length no more than 3× width, more oval or irregularly shaped |
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22 (21) | Central America north to southeast United States (Fig. |
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22’ | Argentina (Fig. |
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23 (21’) | Margin of ostium bursae, antrum, AND ductus bursae without wrinkles, ridges, grooves, or undulations (Fig. |
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23’ | At least some part of margin of ostium bursae, antrum, OR ductus bursae with wrinkles, ridges, grooves, and/or undulations |
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24 (23’) | Colliculum a broad band notched in the middle to form a saddle shape; distinctly demarcated and darker than rest of surrounding cuticle |
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24’ | Colliculum variable or indistinct, but if distinct from surrounding cuticle, not a broad, saddle-shaped band notched in the middle |
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25 (24) | Ostium bursae circular, margin less undulate, only slightly uneven; ductus bursae length at least 2× width, with longitudinal ridges (Fig. |
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25’ | Ostium bursae flattened dorsoventrally, ventral margin distinctly undulate; ductus bursae length subequal to width or only slightly longer, lacking longitudinal ridges (Fig. |
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26 (24’) | Papillae analis with lobelike ventral extension, distinct from smooth, outer sweep of papillae analis (Fig. |
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26’ | Papillae analis normally rounded ventrally, outer sweep continuous (Fig. |
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27 (26’) | Ostium bursae completely open to environment, not concealed by any surrounding cuticle of the lamella antevaginalis or lamella postvaginalis other than undulations of margin |
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27’ | Ostium bursae partially enclosed by pinching of lamella antevaginalis or lamella postvaginalis, opening to environment narrower than ostium bursae (Figs |
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28 (27) | Distance between ostium bursae and posterior margin of sternite VIII subequal to width of ostium bursae; ductus bursae length nearly 2× width, noticeably more darkly sclerotized ventrally (Fig. |
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28’ | Distance between ostium bursae and posterior margin of sternite VIII at least 2× width of ostium bursae; ductus bursae length subequal to width, ventrally no darker than remaining membrane |
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29 (28’) | Ventral and lateral margins of ostium bursae distinctly undulate with deep invaginations forming ridges in beginning of antrum (Fig. |
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29’ | Ventral and lateral margins of ostium bursae barely roughened, walls of antrum unaffected by shape of margin of ostium bursae (Fig. |
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30 (29’) | Sclerotized collar on ductus bursae triangular, surface denticulate, edges jagged, midlength shorter than width of ductus bursae (Fig. |
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30’ | Sclerotized collar on ductus bursae rectangular, surface and edges smooth, midlength subequal to width of ductus bursae (Fig. |
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31 (27’) | Lamella antevaginalis expanded posteriorly over ostium bursae, split in the middle forming a notch between cuticle and exposing ostium bursae; lamella postvaginalis widened into circular opening with wrinkled edges (Fig. |
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31’ | Lamella antevaginalis only slightly extending over ostium bursae with wrinkled ventral margin and without a noticable notch; lamella postvaginalis pinched medially forming a notch over ostium bursae and a groove posterad (Fig. |
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Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Male genitalia:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
Female genitalia, ventral view:
We would like to thank Geoff Martin, Michael Shaffer†, and Kevin Tuck (retired) at the Natural History Museum, London Carnegie Natural History Museum
Distribution of
xls file
Matrix of species of