Chrysopodes (Neosuarius) nigripilosus ( Banks, 1924 )

Tauber, Catherine & Tauber, Maurice, 2010, Two new endemic species of Chrysopodes (Neosuarius) (Neuroptera, Chrysopidae) from the Galapagos Islands, ZooKeys 42 (42), pp. 47-78 : 50-59

Chrysopodes (Neosuarius) nigripilosus ( Banks, 1924)

Diagnosis. Chrysopodes (Neosuarius) nigripilosus specimens from the type locality (Baltra, = South Seymour; all pinned) are distinguished by their overall tan to light tan body color; the pleuron, venter and legs are largely light tan to cream-colored. The vertex is light brown and the facial markings range from light to dark brown (Fig. 1). The forewing membrane is without markings or suffusion; below the stigma there usually are three to four (occasionally two) crossveins between the Subcosta and Radius, (scx); and the second cubital crossvein (cux2) is not bent or crassate, nor does it have an enlarged swelling ( Fig. 4a ). The venter of the male abdomen is largely cream-colored to light tan throughout; in contrast, the female S5 and S6 are entirely brown, S7 is either brown entirely or basally, and the terminus is light to dark brown ( Fig. 6a, b ).

In the males: (a) the horizonal apodeme along the ventral margin of T9+ectoproct is arched and its posterior tip is bifurcated (see Note in brackets below); (b) the gonarcus is arcuate, with the gonarcal arms extending downward, not outward (Fig. 9b, c); (c) the eversible pouches at the tip of S8+9 are large and well separated mesally by a distinctly flat membrane ( Fig. 8 ). In the female, the spermathecal duct is short and it lacks tight coils; the bursal glands are large and globose and their accessory ducts may be branched (Figs 13, 14). The subgenitale bears a pair of invaginated pouches that are near the base of the bursal glands; in C. (N.) nigripilosus , these pouches typically are flat and folded (Fig. 15a).

[Note: In Chrysopidae the apex of the abdomen is opened by two major apodemes articulating with each other at their bases. One apodeme runs along the ventral portion of tergite 9+ecoproct; it is termed the dorsal apodeme (d.a.). The other apodeme runs along the dorsum of sternite 8+9 and is termed the ventral apodeme (v.a.). The dorsal apodeme can be complex, with a dorsal branch (d.b.) along or below the anterior side of the callus cerci, a ventral branch (v.b.) that projects ventrally towards the gonarcus, and a caudal branch (c.b.) that extends distally below the callus cerci and can project beyond the ectoproct.]

Figures Į–3. Head and prothorax. Į Chrysopodes (Neosuarius) nigripilosus 2 C. (N.) nigricubitus 3 C. (N.) pecki . (a) frontal view (b) dorsal view (c) lateral view. The scale applies to all images.

Description of specimens from type locality. Head. (Table 1, Fig. 1a, b, c): Vertex raised, flat, pentagonal shape, with small, upward fold posteriorly; surface of vertex with small, brown setae. Frons smooth, shiny throughout. Clypeus convex basally; surface smooth, mostly flat, very slightly raised in middle. Labrum flat, surface smooth; distal margin straight. Gena smooth, rounded. Coloration: Frons light tan to light brown with pair of brown, subtriangular to roundish marks below toruli; clypeus with lateral margins dark brown. Vertex brown. Toruli light brown, with surrounding sclerotized areas brown to dark brown; dorsal torulus with two dark brown, vertical streaks, larger one extending from below center of scape, smaller one extending from below mesal margin of scape. Genae dark brown, central area with large to small, longitudinal, pale stripe. Scapes light brown to tan, unmarked; pedicel brown basally, lighter distally; flagellum light brown. Maxillary palp: segments 3–5 brown; basal two segments tan. Labial palp with terminal segment brown, basal segments tan. Venter tan to cream-colored; lateral margins of submentum dark brown.

Thorax. (Table 1, Fig. 1b). Pronotum tan to light brown, with scattered, brown, mottled markings sublaterally; several long, thin, pale setae laterally, short, robust, dark brown to black setae dorsally. Mesonotum, metanotum light brown mesally, brown laterally; setae on mesonotum short, robust, dark brown; setae on metanotum sparse, thin, pale. Pleural areas tan to cream-colored, sometimes with brown markings. Legs cream-colored without markings, setae light brown. Tarsal claws amber, long, narrow, with broad cleft, small base; area between claws black.

Wings. (Table 3, Figs 4a , 5a ). Forewing about three times longer than tall, with apex broad, rounded; anterior margin relatively straight; posterior margin curved. Costal area narrow, greatest height ̴0.17–0.18 times height of wing, tallest at costal cell (#5–6). Subcosta, radius (R) slightly sinuate; most costal veinlets, radial crossveins straight; one subcostal crossvein basally, three to four below stigma. Ten to twelve radial crossveins [between R and radial sector (Rs)]; height of tallest radial cell about 0.2 times height of wing. Radial sector slightly thickened at intersection with first radial crossvein (rx1). First intramedian cell ovate, length about 3/4 length of third medial cell; median arculus (ma) thickened. Usually two rows of gradate veins; inner row with three to five gradates in irregular pattern; outer row with six to seven, ̴regularly stepped gradates (six specimens with three rows – the middle row with one to two gradates). Four b cells, four b’ cells; cubitus (Cu) thickened at furcation; three intracubital cells, distal one open, icu1, icu2 each shorter than icu 3; icu1 longer than icu2; second intracubital crossvein (icux2) relatively straight, not thickened, without swellings. First anal vein (1A) forked.

Hindwing narrow, length over three times greater than height, with apex acute. Ten to eleven radial crossveins; three to five inner gradates; six to seven outer gradate veins; three b cells; no t cell; four b’ cells; two intracubital cells, distal one open.

Forewing hyaline, with stigma slightly opaque; costal veinlets within stigma brown, surrounded with suffusion of light brown. Alar membrane almost completely without suffusion of colored pigment. Longitudinal veins cream-colored, marked with dark brown to black at intersections with crossveins. Most costal veinlets, almost all crossveins cream-colored in center, dark brown at tips. Gradates dark brown to black; terminal veinlets dark brown basally, brown at tips, with cream-colored sections mesally. Rs black at intersection with Rx1; ma black; Cu black at furcation; marginal cell below 3A almost completely dark brown to black. Hindwing hyaline; membrane without suffusion of colored pigment; stigma opaque, brownish. Longitudinal veins cream-colored, marked with dark brown at intersections with crossveins; gradates, icu crossvein dark brown; costal veinlets, most crossveins dark brown at tips, cream-colored in center.

Abdomen (male & female) (Table 5, Fig. 6a, b ). Tergite 1 light brown to brown; T2, 3, 6, 7, brown; T4, 5 brown distally; pleural regions cream-colored, mottled with brown; sternites 1–4 cream-colored with cream-colored setae; setae brown on S5–9; Female: S5, S6 brown, S7 brown or brown basally; terminus light to dark brown; Male: S5 to S8+9 cream-colored to tan. Tergites 6, 7: roughly quadrate, with relatively straight ventral margins, straight basal margins, rounded distal margins; length: 1.4–1.5 (T6), 1.1–1.2 (T7) times greater than height (lateral view); with long, robust setae. Pleural region, P7 with dense, medium-length setae. Sternite 6: quadrate, dorsal margin relatively straight; length ̴0.8 times height, with long, robust setae. Spiracles oval, not enlarged, ̴ 0.02–0.04 mm diameter; atria not enlarged.

Male. (Table 5, Figs 7 , 8 , 9a, b, c). Eighth tergite (T8) truncate anteriorly, posteriorly (lateral view). Left and right T9+ectoproct fused dorsally; terminal edge rounded dorsally; vertical margin straight, rounded ventrally; vertical field of long, dense, robust setae distally. Apodeme of T9+ectoproct heavily sclerotized, arched, with three terminal branches: dorsal branch extending upward, internally beneath callus cerci, connecting mesally at top of tergite; short ventral branch extending into membrane below apodeme; caudal branch heavy, extending distally well beyond tip of T9+ectoproct, curved mesally, with rounded, forked tip (Fig. 9a). Callus cerci taller than wide (0.17–0.19 mm tall, 0.13 mm wide), with 31–32 trichobothria. S8+9 length 1.6–1.7 times proximal height; shape in lateral view: triangular to slightly truncate distally, with well sclerotized, sub-basal apodeme extending transversely across entire sternite; terminal membrane modified into pair of eversible, elongate pouches, separated by unmodified, flat, mesal membrane. Subanal plate lightly sclerotized, with large patch of long, delicate setae. Gonarcus arcuate, loosely attached to T9+ectoproct via delicate membrane beneath subanal plate; bridge well-sclerotized, broad, flat transversely, with gonarcal arms extending downward from distal margins of bridge; span of gonarcus near arch 0.31–0.32 mm, span between gonarcal arms distally 0.37–0.46 mm. Gonarcal arms oblong, ̴ 0.32–0.36 mm long. Mediuncus lightly sclerotized, broad basally, more heavily sclerotized, cone-shaped, distally, slightly rounded dorsally; base broadly attached and extending from top of gonarcus, with pair of elongate, internal rods extending along dorsal margin of mediuncus from base to well past middle of mediuncus. Sclerotized surface of mediuncus rough, with very fine striations above, minute microsetae laterally. Tip of mediuncus bent downward, elongate, tapering to rounded, beak-like apex, with thin, mesal flange above beak. Membrane immediately below beak (base of gonosaccus) bearing pair of long, thin, setose glands with grainy interior (glands sometimes ribbon-like – probably teneral condition); base of glands sometimes with short, stout setae, sometimes stemming from crescent-shaped sclerotized protuberances; length of glands approximately two times width of gonarcal bridge; terminus of glands apparently merging with gonosaccus membrane well below origin of ducts; gonosaccus membrane distal to gonarcus folded, with rough-textured surface. Hypandrium internum with pair of broad, almost transparent arms, very flat, wing-like comes. Gonapsis absent.

Female (Table 5, Figs 12, 13, 14, 15). Tergite 8: height of fully sclerotized portion approximately equal to length; height of sclerite (including less sclerotized ventral extension) ̴two times length, unsclerotized portion with numerous medium-length setae. Ninth tergite + ectoproct (lateral view) very slightly tilted – ventral margin extending slightly beneath T8; proximal margin relatively straight throughout or slightly convex; distal margin curving beneath ventral margin of gonapophyses laterales (mature specimens). Callus cerci taller than broad (0.16–0.17 mm tall, 0.10–0.14 mm wide), with ̴31–36 trichobothria. Gonapophyses laterales 0.4–0.5 times height of T9+ectoproct; ̴2.6–4.7 times taller than wide; with robust setae dorsally, shorter, thinner setae ventrally; rounded dorsally, ventrally; orientated posteroventrally (̴60– 70° angle from midline). Sternite 7: with long, robust setae; length ̴1.6 times height of proximal margin (lateral view), with distal 1/4 sloping abruptly to terminus; terminus almost as tall as midpoint of segment. Subgenitale narrow, rounded, with broad, bilobed, distal process; base consisting of light, folded membrane, attached to S7 via delicate, invaginated membrane; lateral margin of base with pair of small, flat pouches, near but separate from base of bursal glands; pouches ̴1/6 length of spermatheca. Pair of large, bulbous bursal glands with narrow, elongate ducts opening on dorsolateral margin of bursa (ducts possibly with small setae or scales), with broad, elongate, sometimes branched, accessory ducts distally. Bursa narrow (<1/2 width of segment), but completely covering spermatheca; membrane heavier basally than distally, dorsum with longitudinal folds, opening ventrally to bursal duct. Bursal duct broadly fluted, transversely folded, immediately below bursa. [The origin of the fluted area below the bursa is not completely clear. We consider it to be an enlarged part of the bursal duct and label it as such on the figures. However, we recognize that it could be part of the bursa copulatrix, in which case the bursal duct would be greatly reduced.] Spermatheca elongate, tubular, with distal end slightly bulbous, one bend, after midsection (to the right), open to bursa via elongate dorsal slit throughout; 0.12 mm diameter at mouth (distal end), 0.18 mm diameter in midsection (widest area), 0.5–0.6 mm long; invagination oblong, extending ̴1/2 length of spermatheca (length 0.23–0.25 mm); velum not identified. Spermathecal duct short, not well sclerotized at tip, ̴ 0.65 mm long (not including pale, brushy tip), extending from slit on dorsal margin of spermatheca, curving, entering subgenitale, making U-shaped curve along dorsal surface of subgenitale cavity, then looping in front of spermatheca; distal ¼ brushy. Colleterial gland elongate, narrow, extending slightly into A6, with smooth, untextured surface, base with bulbous, folded reservoir near terminus of duct; no accessory glands found. Transverse sclerification curved, eliptoid, plate-like, located mesally within gonopophyses laterales, with two rows of setae (setae longer mesally than laterally).

Intraspecific variation. See measurements (Tables 1, 3).

Baltra. The lectotype (AMNH) is teneral. It has a mediuncus that is characteristic of mature specimens, but the gonarcal arms are barely formed, the glandular ducts are visible only in a small region at the base of the gonarcal arms, and the eversible pouches are small and withdrawn. The dissected paralectotype (MCZ) is mature, with structures as described above.

Santa Cruz (Academy Bay). The large series of specimens from this locality are relatively uniform, and in all the features that we measured, they overlap with those from the type locality. Although they tend to have somewhat longer wings (Table 3), their head size and proportions, as well as the features of the wings, are well within the range of the Baltra specimens (Tables 1, 3).

The dorsal surface of specimens from Academy Bay is relatively dark (light brown to brown); the lateral and ventral surfaces of the thorax are light brown to tan; dorsally the abdomen is cream-colored to light brown, with areas marked with brown; ventrally the abdomen is cream-colored to light tan (entirely in the males; with S5, S6 and S7 brown in the females). The facial markings range from medium depth to dark. The membrane of the wings is without markings or suffusion; the degree to which the Rs, ma and Cu are thickened is small; and there are three to four crossveins below the stigma. In the four dissected males, (a) the gonarcal arms are oriented downward; (b) the eversible pounches are large and well separated. [Note: One of the ̴ 65 specimens has a small amount of suffusion around the gradates and some crossveins, but none of the other characteristics of C. (N.) nigricubitus ; four of 65 specimens (from the 1968 Edinbrough University Expedition) have two crossveins below the stigma; of these, two have three crossveins on the opposite wing.]

Isabela. The C. (N.) nigripilosus specimens from Isabela overlap with the Baltra specimens in the features we examined. Among these specimens (both pinned and in alcohol), there were no distinguishing features with regard to head size, head features, or wing size or wing features (See measurements, Tables 1, 3).

The overall body color is tan with mottled, light to medium brown dorsal markings; the ventral abdominal markings of the males and females match those of the Baltra population. The facial markings range from light to medium brown. The membrane of the wings is without markings or suffusion; the degree to which the Rs, ma and Cu are thickened is small; and there are three to four crossveins below the stigma. On the two dissected male specimens from this island: (a) the gonarcal arms extend downward from the gonarcal bridge, parallel with the mediuncus, and (b) the eversible pouches are short and highly folded; although they are fully separate, the area between them is membranous and loose.

Fernandina. In general, the specimens from this island (2 pinned and 7 in alcohol) overlap with the Baltra specimens. The degree to which the Rs, ma and Cu are thickened is small; the membrane of the forewing is clear and without marks; there are three crossveins below the stigma (Table 3).

Santa Fe, Santiago . The single female specimens from Santa Fe and Santiago Islands have features that are typical of the Baltra population (Tables 1, 3).

Specimens examined (in addition to the type material; all are pinned unless noted otherwise): Baltra (= South Seymour). South Seymour, IV/23/1923, Williams Galápagos Exped., Dept. of Tropical Research, N. Y. Zoological Society, William Beebe, Director (1M, Lectotype, AMNH) ; So. Seymour Isl. , IV/20/1923, Am. Mus. Exped. (1M, 2F, 1 abdomen missing, Paralectotypes, MCZ) ; 30 m, S. Peck , I/24/1989, arid zone, grass+ Bursera Forest , UV light, 89–4 (2M, USNM) ; 10 m, I/23/1989, S. Peck, arid zone, Bursera Forest , UV light, 89–5 (1F, USNM), beating or on ground, 89–12 (1M, USNM). Santa Cruz (= Indefatigable). CDRS, Arid zone, II/5–9/1989, dung tp., B. J. Sinclair (1F, USNM) ; Academy Bay , II/17/1964, P. D. Ashlock, (1M, 1F, BPBM) ; 0–100 m IX/1970, J. & M. Sedlacek (2F, BPBM) ; Academy Bay , Darwin Research Station, I/25-II/27/1964, D. Q. Cavagnaro & R. O. Schuster (3M, 11F, CAS), III/21/1964, D. Q. Cavagnaro (1M, CAS), I/30/- III-20/1964, R. O. Schuster (30M, 13F, CAS), I/21-II/1/1964, E. G. Linsley (2M, 1F CAS) ; CDRS, X/12–27/1968, Edin. Univ. Exped 1969.71 (4F, 2?, NSM, det. A. R. Waterston , 1970). Isabela (= Albemarle ). nr, Punta Tortuga N, of Tagus Cove, I/28–30/1967, edge of mangrove swamp, among Bursera graveolens, I. L. Wiggins (1M, CAS) ; Puerto Villamil , MVL, III/2/1989, B. Laudry (1M, 1F, USNM) ; V. Alcedo , arid zone, 200m, Palo Santo woodland uv light, IV/3/1996, S. Peck, 96–78 (1M, 1F, USNM) ; V. Wolf , summit arid, 1700m, sweeping shrubs, V /21/1996, S. Peck, 96–201 (1F, USNM) ; Beagle Crater , 3 m. (beach), III/25/1988, 4 m. (beach), III/23/1988, L. Baert, K. Desender & J.-P. Maelfait (6M, 2F, IRSNB, Sample #B.88/0478; alcohol) ; Volcán Wolf , 4 m. (beach), III/20/1988, L. Baert, K. Desender & J.-P. Maelfait (2M, 5F, IRSNB, Sample #B.88/0446; alcohol) ; Volcán Wolf , 4 m. (beach), III/23/1988, L. Baert, K. Desender & J.-P. Maelfait (11M, 8F, IRSNB, Sample #B.88/0470; alcohol). Fernandina (= Narborough). W side, 1,100’, II/5/1964, D. Q. Cavagnaro (2F, CAS) ; Beginning of encañada, V /4/1991, L. Baert, K. Desender & J.-P. Maelfait (1F, IRSNB, Sample #B.91/0765; alcohol) ; Cabo Hammond , 5 m, V/12/1991, L. Baert, K. Desender & J.-P. Maelfait (4M, 2F, IRSNB, Sample #B.91/0802; alcohol). Santa Fe (= Barrington). Lagoon, 400 m, IV/24/1991, L. Baert, K. Desender & J.-P. Maelfait (1F, IRSNB, Sample #B.91/0722; alcohol). Santiago (= San Salvador, James). Settlement, IX/22/1968, Edin. Univ. Exped. 1969.70 (1F, NMS, det. A. R. Waterston 1970) .

[Note: Additional specimens from Santa Cruz Island are in the NMS.]

Figures

Figure 4. Forewing. Į Chrysopodes (Neosuarius) nigripilosus 2 C. (N.) nigricubitus 3 C. (N.) pecki. icux2, second intracubital crossvein; i.g., inner gradate veins; ma, median arculus; scx, subcostal crossveins (between subcosta and radius). The scale applies to all images.

Figure 5. Base of forewing. a Chrysopodes (Neosuarius) nigripilosus b C. (N.) nigricubitus c C. (N.) pecki. icux2, second intracubital crossvein; ma, median arculus.

Figure 6. Abdomen, ventral view.a Chrysopodes (Neosuarius) nigripilosus male b Chrysopodes (Neosuarius) nigripilosus female c C. (N.) nigricubitus female d C. (N.) pecki female. The scale applies to all images.

Figure 7. Male abdomen, lateral view. Chrysopodes (Neosuarius) nigripilosus. c.a. tip of caudal apodeme on T9+ectoproct c.c. callus cerci d.a. dorsal apodeme on T9+ectoproct ev.p. eversible membranous pouch gs gonarcus (lateral apodeme) s.a. sub-basal apodeme on S8+9 s.dt. setose duct s.p. setose subrectal plate S7 seventh sternite S8+9 fused eighth and ninth sternites T8 eighth tergite T9+ect fused ninth tergite and ectoproct v.a. ventrally projecting arm of apodeme on T9+ectoproct.

Figure 8. Male abdomen, lateral view. Chrysopodes (Neosuarius) nigripilosus. Note pair of eversible pouches at terminus of S8+9.