Apochrysa voeltzkowi Larvae

Tauber, Catherine A., 2014, Apochrysinae (Neuroptera: Chrysopidae): New Larval Description and Subfamilial Comparisons, Zootaxa 3835 (2), pp. 198-208 : 202-207

Apochrysa voeltzkowi Larvae

Descriptions. First instar (neonate). Body ( Fig. 2A ) length ~ 1.6 mm (measured in lateral view through spiracles), depth not measured. Dorsal surface of preserved specimens cream-colored, without markings; lateral tubercles (LTs) of thorax, abdomen, laterodorsal tubercles (LDTs) of abdomen with light brown tinge distally; large abdominal chalazae (A1–A5) light brown. All setae smooth, pale, of various lengths and robustness; thoracic setae with acute tips; most abdominal setae (submedian setae, SMS) with small terminal hook.

Head ( Figs 2B–D ) cream-colored, with very light brown dorsal markings as in Fig. 2B ; eyes with stemmata clear (tissue beneath black); integument surrounding margins of anterior stemmata light brown, integment surrounding margins of ventral, posterior and posterodorsal stremmata clear; cranium rounded posteriorly; width (across eyes) ~ 0.42 mm, length (dorsum) ~ 0.32 mm, depth not measured; cranial base exposed to slightly withdrawn into cervix. Anterior margin of cranium straight between mandibles, tapering posteriorly from mesal margin of mandibles to eyes; labrum recurved ventrally. Eyes protruding laterally; stemmata clustered tightly on anterior and lateral surfaces of protrusion; anterior two stemmata large, globose, posterior three and central stemmata smaller, less prominent.

Cephalic appendages ( Figs 2C, 2D , 3A, 3B ) relatively elongate, slender. Mandible long, thin, length (along curve) ~ 0.47 mm, length (straight line) ~ 0.37–0.39 mm, width ~ 0.06–0.07 mm; ratio mandible length (curved) to head width = 1.17–1.24; ratio mandible length (curved) to head length (dorsal) = ~1.5. Mandible with three short, acute basolateral setae; terminus with very small teeth, sharply acute tip. Antennal length 0.57–0.58 mm, ~1.8x length of cranium; width ~ 0.03 mm (at widest part of pedicel); scape with straight sides, setae apparently absent; pedicel, flagellum long, slender; pedicel with small mesal seta distally; flagellum about 0.76–0.79x length of pedicel, tapering gradually from pedicel; terminus almost 0.1 mm long, ~0.33–0.38x length of flagellum, with single long, tapering bristle. Labial palp long, wider than antenna, ~0.7–0.8x length of mandible (straight line); basal segment with one long, distolateral seta; middle segment long, annulate throughout, with two long, robust setae distally, one mesal, one lateral; terminal subsegment elongate, ~one-third length of middle segment, slightly tapered distally, with transverse striations throughout, without visible sensillae, setae or terminal bristles, with cluster of microsetae terminally; palpiger approximately same size as basal segment of palpus, with one mesal seta, one lateral seta anteriorly; mentum with two pairs of long, anterior setae, two pairs of lateral setae – one short, one long; stipes elongate, narrow, diverging mesally from cranial margin; cardo shorter, angled posteriorly. Cervix small, with one pair of small setae anterolaterally; sclerites not discerned. Venter with row of three short setae (R1) laterally.

Thorax ( Figs 2A , 4A ) with sclerites not distinguished from membranous integument; each segment with pair of lateral tubercles (LTs), each bearing two (prothorax) or three (mesothorax, metathorax) elongate setae (LS); prothoracic LT without small seta between two large LS. LTs well developed, but not large; LS with tapered, acute or very finely hooked tips. Legs setose, cream-colored, without markings except at coxal base, tarsal tip; claw, empodium light brown.

Prothorax (T1) with pair of medium-length setae (S1) anteromesal to LTs, small seta (probably S2Sc1) at mesal base of each LT, pair of long setae submesally (probably S1Sc1), three pairs of setae (S3, S4, S5) posterolaterally; S2 apparently missing. Venter (posterior region) with pair of medium-length, submesal setae.

Mesothorax (T2) with anterior subsegment bearing two pairs of small setae (probably S1Sc1, S2Sc1) on anterior margin, bearing spiracles laterally; spiracles simple, sessile, circular, with small atrium, without associated seta. Posterior subsegment with two pairs of very small setae (probably S1Sc2, S2Sc2) on anterior margin, two pairs of medium-length setae between LTs, pair of short setae at base of LTs, two pairs of setae posteriorly, slightly longer than two anterior setae. Venter apparently without setae.

Metathorax (T3) with three pairs of very small setae (probably S1Sc1, S2Sc1, S3Sc1) on anterior margin, transverse row of three pairs of medium-length setae mesal to LTs, two pairs of elongate setae from robust chalazae posteriorly. Venter apparently without setae.

Abdomen ( Figs 2A , 4B, 4C ) with LTs, LDTs present on A1–A7; LT on A1 with one LS; LTs on A2–A7 each with two LS, without small seta between LS. Spiracles circular, sessile, with small, simple atrium, each with small, acute-tipped (A1–A3, A6–A8) or medium-length, lightly hooked (A4, A5) associated seta (SSp). A1: LS long, acute; LDT with one long, hooked LDS, one very small LDS; dorsum with anterior transverse row of four small setae with acute tips, posterior row with four elongate, lightly hooked SMS from large chalazae. Venter with single pair of submesal setae. A2–A7: LS elongate, lightly hooked to acute; LDTs each with two LDS, one elongate, lightly hooked, one short, acute (A2), medium-length, lightly hooked (A3–A4), or elongate, lightly hooked (A5–A7). Dorsum with anterior transverse row of four medium-length setae—acute (A2) to hooked, blunt, or spatulate (A3–A7); one pair of elongate, hooked SMS on large chalazae between LDTs. Venter with one pair of small to medium-length submesal setae anteriorly, two pairs of submesal setae posteriorly, lateral ones long. A8: LTs short, broad, with relatively short LS, with two pairs of small setae in transverse row between spiracles; two pairs of large, acute-tipped SMS between LTs. Venter with transverse posterior band of approximately eight short to medium-length setae. A9: Cylindrical; dorsum with two transverse rows of long setae arising from chalazae. Venter with transverse posterior band of approximately eight short to medium-length setae. A10: Dorsum largely without setae, except for two pairs of small, terminal setae. Venter with two pairs of small setae near terminus; terminus with small patch of microsetae.

Second and third instar. Body ( Fig. 5A ) length ~ 7.3–8.9 mm (measured in lateral view through spiracles), depth ~1.7–2.0 mm (thickest section of abdomen). Coloration of living specimens pure white with thin, greyish median line and abdominal spots; mandibles, tips of legs light brownish to amber [Photo by P. Duelli, Fig. 129 in Aspöck & Aspöck 2007]. Dorsal surface of preserved specimens cream-colored, with sclerites, markings light brown. All setae smooth, pale, of various lengths and robustness, most thoracic setae with acute tips, some elongate setae on lateral tubercles with hooked tips. Most abdominal setae (submedian setae, SMS) with small terminal hook.

Head with light brown to brown markings as in Figs 5B (dorsal), 5C (ventral); 5D (lateral); eyes with stemmata clear; integument surrounding margins of anterior stemmata brown, integment surrounding margins of ventral, posterior and posterodorsal stemmata clear (tissue beneath black); cranium tapered posteriorly, angular ventrally, dorsal surface quadrate posteriorly; width (across eyes) ~ 0.93–0.95 mm, length (dorsum) ~ 0.72 mm, depth (midregion, to top of eye) ~ 0.23–0.24 mm; cranial base exposed to slightly withdrawn into cervix. Anterior margin of cranium straight between mandibles, tapering posteriorly from mesal margin of mandibles to eyes; labrum recurved ventrally. Eyes protruding laterally; stemmata clustered tightly on anterior and lateral surfaces of protrusion; anterior two stemmata large, globose, posterior three and central stemmata smaller, less raised.

Cephalic appendages ( Figs 1A , 5B, 5C , 7A, 7B ) relatively elongate, slender. Mandible long, thin, length (along curve) ~ 1.06–1.15 mm, length (straight line) ~ 0.84–0.93 mm, width ~ 0.06–0.07 mm; ratio mandible length (curved) to head width = 1.17–1.24; ratio mandible length (curved) to head length (dorsal) = ~1.5–1.6. Mandible with single acute basolateral seta; terminus with very small teeth, sharply acute tip. Antennal length 1.3 mm, ~1.6x length of cranium; width ~ 0.04 mm (at widest part of pedicel); scape with straight sides, single pair of short, distolateral setae; pedicel long, slender; flagellum long, slender, about 0.45x length of pedicel, tapering gradually from pedicel; basal flagellomere without mesal seta, terminus with single long bristle. Labial palp long, slender, ~0.9x length of mandible (straight line); basal segment with one long, distolateral seta, ~ three long distomesal setae; middle segment long, annulated throughout, with basal region bearing approximatley seven long setae, mostly mesal, distal region with four long, robust setae, three mesal, one lateral; terminal subsegment elongate, ~one-third length of middle segment, slightly tapered distally, with transverse striations throughout, with four lateral-ventrolateral sensillae, without setae or terminal bristles; palpiger erect, with slightly rounded sides, one mesal seta, one lateral seta; mentum with leathery plate mesal to stipes, with four pairs of long setae; stipes elongate, narrow, angled approximately parallel to cranial margin; cardo shorter, angled mesally, with small dark brown spot at posterior tip. Cervix collar-like, with band of setae ventrally, laterally, with few or no setae dorsally, with pair of brown sclerites laterally.

Thorax ( Figs 5E , 6A, 6B , 8A ) with each segment bearing relatively dense covering of medium-length dorsal setae. Legs highly setose, cream-colored, without markings except at coxal base, tarsal tip; claw, empodium brown ( Fig. 1B ).

Prothorax (T1) with two subsegments separated by shallow fold. Sc1 light brown, oblong, extending almost full length of second subsegment; Sc2 large, approximately pear-shaped. Venter with pair of large setae anteriorly, rows of smaller setae mesally, posteriorly.

Mesothorax (T2) with three, well delineated subsegments separated from each other by two distinct, smooth transverse folds; Sc2 small, embedded in first fold, with minute seta; Sc3 large, round, light brown, at lateral terminus of second fold. Venter with ~50 short, scattered setae, one pair of long to medium-length setae posteriorly.

Metathorax (T3) with three subsegments separated by two small folds. Sc2 large, light brown, round; posterior subsegment with transverse row of approximately 15 setae slightly longer than those elsewhere on thorax. Venter with two transverse bands of approximately eight short to medium-length setae.

Abdomen ( Figs 5F–H , 6C , 8B, 8C ) with laterodorsal tubercles smooth, each with 2–4 elongate robust setae (LDS), several shorter LDS. Spiracles circular, sessile, with small, simple atrium. A1: Segment with two subsegments separated by small fold. Anterior subsegment small, spindle shaped, with spiracle on lateral margin. Posterior subsegment longer, broader than first, with distinct LDT laterally. Dorsum of each subsegment with transverse bands of numerous elongate to short SMS; venter with single transverse band of ~12–15 short to medium-length setae. A2–A7: Segment with three subsegments separated by small folds. Subsegments roughly of similar size, each extending to margin of segment; dorsum of anterior subsegment with transverse band of 8–10 SMS; middle subsegment bearing spiracle laterally, transverse band of 10–12 SMS; posterior subsegment with pair of distinct, smooth LDTs laterally. Venter with two to three transverse bands of short to medium-length setae; each segment with posterior pair of long, prominent setae submesally. A8: LTs short, broad, with relatively short LS; spiracle at anterior base of LDT; anterior, middle subsegments each with transverse row of ~four SMS; posterior subsegment with ~12 SMS. Venter with posterior band of four robust setae, several shorter setae. A9: Cylindrical, brown marking anteromesally, with numerous short setae, especially robust laterally, dense posterolaterally. A10: Dorsum with longitudinal brown marking mesally, with scattered small setae laterally, with inflated, bilobed membrane terminally.

Larval diagnosis. Based on the description above and that of Tsukaguchi (1995) for A. matsumurae , it appears that the third instars of the two species are very similar morphologically. Thus they can be distinguished from known larvae in other chrysopid subfamilies by their elongate flagellar segments. The main differences between the two Apochrysa species are in the head and body markings. Tsukaguchi reported that his specimens of A. matusumurae were without markings, whereas our specimens of A. voeltzkowi (L3) have distinct, although light, brown head and body markings ( Figs 5B–5H , 7A ). First instars of A. matusumurae are not described, but the first instar of A. voeltzkowi also has faint head markings that may be distinctive ( Figs 2B , 3A ).

Figures

FIGURE 1. Apochrysa voeltzkowi (Weele) third instar. A. Terminal segment of labial palpus (distal section) bearing four sensilla. B. Prothoracic tarsus and empodium. Both structures cleared, mounted in glycerin. Abbrevations: emp, empodium; sen, sensilla.

FIGURE 2. Apochrysa voeltzkowi (Weele) first instar. A. Body, dorsal. B. Head, dorsal. C, D. Cephalic appendages, dorsal (cleared, mounted in glycerin). C. Flagellum. D. Mouthparts, base of antenna. Arrow indicates tip of pedicel (connection).

FIGURE 3. Apochrysa voeltzkowi (Weele) first instar. A. Head, dorsal. B, Ventral. Abbreviations: br, bristle; co, cardo; fl, flagellum; fr, frontal marking; md, mandible; mx, maxilla; ped, pedicel; post, postfrontal marking; stp, stipes; Sx, primary cephalic seta number; Vx, Vx setae.

FIGURE 4. Apochrysa voeltzkowi (Weele) first instar. A. Thorax. B. First to third abdominal segments. C. Seventh to tenth abdominal segments. Abbreviations: Ax, abdominal segment number; LDS, primary seta on LDT; LDT, laterodorsal tubercle; LS, primary seta on LT; LT, lateral tubercle; sp, spiracle; Sx, primary seta number; SxScx, seta associated with sclerite, numbers; SMS, submedian seta; SSp, seta associated with spiracle.

FIGURE 5. Apochrysa voeltzkowi (Weele) third instar. A. Body, lateral. B. Head, dorsal. C, Head, ventral. D. Head, lateral. E. Thorax, dorsal. F. First to third abdominal segments. G. Fourth to seventh abdominal segments. H. Sixth to tenth (terminal) abdominal segments.

FIGURE 6. Apochrysa voeltzkowi (Weele) third instar. A. Prothoracic lateral tubercle. B. Metathoracic lateral tubercle. C. Lateral tubercle of second abdominal segment. All cleared, mounted in glycerine.

FIGURE 7. Apochrysa voeltzkowi (Weele) third instar. A. Head, dorsal. B, Ventral. Abbreviations: br, bristle; co, cardo; fl, flagellum; fr, frontal marking; md, mandible; mx, maxilla; ped, pedicel; sc, scape; sen, sensilla; stp, stipes; Sx, primary cephalic seta number; Vx, Vx setae.

FIGURE 8. Apochrysa voeltzkowi (Weele) third instar. A. Thorax. B. First to third abdominal segments. C. Sixth to tenth abdominal segments. Abbreviations: Ax, number of abdominal segment; LDT, laterodorsal tubercle; LS, primary seta on LT; LT, lateral tubercle; sp, spiracle; Scx, primary sclerite number; SMS, submedian seta; Tx, thoracic segment number.