Neocorvicoana reticulata (Kirby, 1819)

Ibarra-Polesel, Mario G., Neita-Moreno, Jhon C., Larrea, Dario D. & Damborsky, Miryam P., 2017, Description of the larva and pupa of Neocorvicoana reticulata (Kirby, 1819) (Coleoptera: Scarabaeidae: Cetoniinae: Gymnetini), Zootaxa 4358 (3) : -

Neocorvicoana reticulata (Kirby, 1819)

( Figs. 1–13 )

Third instar. Dorsal body length 44.8–45.9 mm, width 7.4–8.2 mm, weight 1.2–1.6 g (preserved specimens). Cranium ( Fig. 1 ): Width of head capsule 2.5–2.8 mm. Color orange brown. Surface mostly smooth, with few pits. Epicraneal, frontal, and clypeofrontal suture distinct. Frons ( Fig. 1 ): Surface with 2 short anterior frontal setae, 2 short exterior frontal setae, and 2 posterior frontal setae; each frontal anterior angle with 1 long seta. Dorsoepicranium with 1–2 long dorsoepicranial setae followed by 5–10 small setae in a line diverging from mediobasal portion of head, and one lateral line of 4–8 small posterior frontal setae at each side. Two long anterior epicranial setae and 2–4 exterior epicranial setae. Stemmata absent. Clypeus ( Fig. 1 ): Shape subtrapezoidal with 2 posterior clypeal setae and 2 exterior clypeal setae at each side. Preclypeus weakly sclerotized, without setae. Labrum ( Fig. 1 ): Symmetrical, rounded margins and anterior border trilobed, clithra present. With 2 long central setae and 4–8 short setae; 2 lateral long setae at each side, without posterior labral setae. Epipharynx ( Fig. 2 ): Plegmata absent. Corypha with 4–6 long stout setae. Haptomeral region without heli or haptomeral process. Zygum transverse, slighthly convex an arcuate row of 14–18 spinelike setae and 10 stout setae irregularly placed behind row. Acanthoparia with 6–10 short setae. Right chaetoparia with 30–45 setae and left chaetoparia with 25–35 setae. Pedium without sensilla. Acroparia with 2–4 long stout setae on each side. Dexiotorma well developed, transversally extended with poorly developed pternotorma. Laetorma short with pternotorma small and rounded. Nesia with sensorial cone. Haptolachus without sensilla below the cone. Left mandible ( Fig. 3A–C ): Scissorial region with 3 teeth well developed, teeth 1–2 separated by an acute scissorial notch and teeth 2–3 by broad furrow. Dorsal surface with 2 stout, long setae at level to basal scissorial notch, one seta in central area and other more lateral; 4–6 dorsomolar setae in tuft. Lateral edge with 4–7 setae. Ventral surface with elongate-oval stridulatory area ( Fig. 3D ), length approximately 2.6 times its width and formed by 14–15 subparallel ridges. Molar area with a tuft of around 8 ventral molar setae. Molar lobe large, forming a dorsoventral ridge, not subdivided. Molar crown with 2 lobes. Acia absent. Ventral process distinct, blunt, with asperites. Brustia formed by 6–9 setae. Postartis large, rounded. Right mandible ( Fig. 4A–C ): With 2 well-developed scissorial teeth below a vestigial tooth. Dorsal surface with 2 stout, long setae at level to the second scissorial tooth; 4-6 dorsomolar setae in tuft. Lateral edge with 5–9 setae. Ventral surface with elongate-oval stridulatory area ( Fig. 4D ), length approximately 2.4 times its width and formed by 13–15 subparallel ridges. Molar area trilobed, with a tuft of around 8 ventral molar setae. Calyx wide. Ventral process well developed, blunt, with asperites. Brustia formed by 11–13 setae. Postartis large, rounded. Maxilla ( Fig. 5A ): Galea and lacinia fused, forming mala. Mala with large uncus at apex and 3 subterminal unci fused at bases, the central uncus much larger than the lateral unci ( Fig. 5B ). Dorsal surface of the mala with approximately 25 setae. Maxillary palpus with 4 palpomeres, palpomere 4 almost as long as palpomeres 2 to 3 together; palpomere 3 with lateral seta. Stridulatory area with row of 5–6 curved acute teeth and a distal, truncate process ( Fig. 5C ). Labium ( Fig. 6 ): Hypopharyngeal sclerome asymmetrical, left side with 4–6 setae; dorsal surface with well-developed, truncate process; both lateral lobes with 4–7 setae arranged in 2 rows. Glossa with 18–22 stout and 18–20 slender setae; apical area with transversal row of 6 sensillae and additional 2–4 sensillae below the row. Labial palpus with 2 palpomeres. Antennae ( Fig. 1, 7A–B ): Terminal antennomere almost as long as the antennomeres 2 and 3 together. Surface of terminal antennomere with 5 sensory spots: 2 dorsal, 2 ventral, and 1 apical. Thorax ( Fig. 10 ): Thoracic spiracle ( Fig. 8A ) with C-shaped respiratory plate, yellowish brown, size 0.32–0.36 mm long and 0.20–0.24 mm wide. Lobes of respiratory plate separated, with 22–26 holes across diameter at middle, holes irregularly oval ( Fig. 8D–E ). Dorsal surface of each segment with many short setae and some slender, long setae (see Table 2). Legs ( Fig. 9A–F ): Tarsungulus cylindrical, rounded apically ( Fig. 9A–C ). Tarsungulus bearing 7 long setae; prothoracic tarsungulus short (0.24 mm) in relation to mesothoracic (0.29 mm) and metathoracic (0.38 mm). Legs growing gradually from the first to the third pair ( Fig. 9D–F ). Coxa, trochanter, femur, and tibia of all legs with many long, stout setae. Abdomen ( Fig. 10 ): Abdominal spiracle I ( Fig. 8B ) smaller (0.32–0.36 mm long, 0.16–0.20 mm wide) than spiracles II–VIII; spiracles of segments II–VII subequal in long (0.36–0.40 mm), but increasing in wide towards posterior segments (0.20 to 0.32 mm) ( Fig. 8C ); spiracle of segment VIII slightly shorter than the spiracles on segments III–VII. Distance between the two lobes of respiratory plate of spiracles slightly less than the dorsoventral diameter of the bulla, or as long as such diameter ( Fig. 8A–C ). Bulla irregularly oval, slightly convex. Dorsum of segment VII and VIII each divided into 2 annulets (prescutum and scutum); segments IX and X fused with many short setae. First abdominal segments with a higher proportion of long and slender setae than the terminal segments (see Table 2). Raster ( Fig. 11A ): Palidia monostichous, open posteriorly and closed anteriorly, sometimes open anteriorly ( Fig. 11B–C ); each palidium consisting of a row of 12–20 pali with flattened apex. Septula oval, length 2.3 times its width. Tegilla composed of 35–45 short, thick setae. Lower anal lip with 24 sparse, short setae and 10 long setae approximately. Anal slit bordered by dense rows of medium size setae.

Segment/Terguite PRSC SCU SCL SPA PLL Female pupa ( Figs. 12A–D ). Length 16.1 mm; greatest width 9.4 mm, weight 0.6 g (preserved specimens). Shape subovate, stout, adecticous, exarate. Color yellowish brown. Entire body with very fine velvety microtrichia. Head: Mouthparts directed ventrally; antenna, labrum, mandibles, maxillae, and palps discernible; antennal tecae expanded, stout, with apices rounded. Compound eyes partially covered by the anterior edges the pronotum, with 2 tubercles between eyes. Clypeus trapezoid, slightly concave. Surface of frons slightly convex. Thorax: Pronotum convex, with well-defined margins, subheptagonal in shape, widest posteriorly; basal margin distinctly bisinuate, center base projecting posteriorly as in adult. Pronotal disc slightly convex, with 2 large protuberances near at the basal angles, weakly depressed at anterior angles. A narrow, median, longitudinal sulcus extending from apex to near base. Mesoscutellum and metascutellum acute, projecting posteriorly. Thoracic spiracle present in cavity formed between the anterior and medial legs, hypomeron, and elytral thecae. Mesometasternal process large and clearly discernible, with rounded apex emerging between the procoxa and mesocoxa. Metasternum wider than long. Pteroteca free, closely appressed, curved ventrally around body; posterior wing theca reaching the abdominal sternite V. Legs: Protibia with 2 short teeth on external apical border and with tubercle-like apical spurs. Mesotibia and metatibia each with 2 well-developed inner and external spurs and with 2 apical teeth. Metafemur covered by elytra and wings. Tarsomeres and pretarsus distinct; pretarsus of protibiae at level of mesofemur, pretarsus of mesotibia at level of abdominal sternite II, pretarsus of metatibia at level of abdominal sternite VII. Abdomen: Tergites II–VI convex, segments II, III, and IV widest; pairs of dioneiform organs not sclerotized between segments I–II, II–III, III–IV, IV–V, and V–VI, between segments VI–VII with only one dioneiform organ. Tergolateral tubercles II–VI prominent and the inner side of each tubercle a longitudinal fold. Spiracles I–IV light brown, tuberculiform, with ring-like, sclerotized peritreme; spiracle I partially covered by wing thecae. Spiracles V–VIII closed, tuberculiform, prominent, surrounded by fine rugae. Sternites VII and VIII with very fine, velvety, microtrichia. Terminal tergite with lateral rugae around small tubercle; narrow fleshy lobes with velvety-gold vestiture, extended to ventral-apical side, forming a rounded apex; without urogomphi. Terminal sternite with roughness on apical area; genital ampulla convex, wide, with genital pore distinct ( Fig. 12D ).

Male pupa ( Figs. 13A–D ). Length 14.1 mm; largest width 8.7 mm, weight 0.4 g (preserved specimens). Protarsus, mesotarsus, and metatarsus longer that female; pretarsus of protibiae surpass the mesofemur, pretarsus of mesotibia at level of abdominal sternite III, pretarsus of metatibia at level of abdominal sternite VIII. Dioneiform organs less evident than the female. Terminal tergite with lateral rugae around small tubercle; narrow fleshy lobes with velvety-gold vestiture, extended to apical side, forming a blunt apex; without urogomphi. Terminal sternite with roughness on apical area; genital ampulla very convex, rounded, and distinct ( Fig. 13D ).

Distribution. Neocorvicoana reticulata occurs in Argentina, Brazil, Paraguay, and Uruguay (Ratcliffe & Micó 2001) and French Guiana and Peru ( Di Iorio 2013). Two records from French Guiana and Surinam are considered erroneous by Ratcliffe & Micó (2001). In its southernmost distribution, this species reaches temperate areas (latitude 39°S) of northern Patagonia, Argentina ( Di Iorio 2013).

Natural history. Larvae collected in November 2013 reached their largest size in late December. In mid- January 2014 all specimens were in the pupal stage, by late January - early February the adults emerged. Adults have been captured during all months of the year (Ratcliffe & Micó 2001).

Figures

FIGURES 1–7. Neocorvicoana reticulata, third instar. 1, Cranium, frontal view; 2, epipharynx; 3, left mandible, dorsal view (A), lateral view (B),ventral view (C), and detail of stridulatory area (D); 4, right mandible, ventral view (A), lateral view (B), ventral view (C), and detail of stridulatory area (D); 5, right maxilla, dorsal view (A), apex of mala showing unci (B), and stridulatory teeth of maxilla (C); 6, dorsal view of labium; 7, antenna in lateral view (A), and third and fourth segment of antenna in ventral view (B).

FIGURES 8–11. Neocorvicoana reticulata, third instar. 8, Spiracles, thoracic (A), first abdominal (B), sixth abdominal (C), and spiracular holes (D and E); 9, prothoracic (A), mesothoracic (C), and metathoracic (E) tarsungulus in dorsal view, and lateral view of prothoracic (B), mesothoracic (D), and metathoracic (F) legs; 10, third instar, entire body in lateral view; 11, terminal abdominal segment,ventral view (A), and detail of raster (B and C).

FIGURES12–13. Neocorvicoanareticulata, pupa.12, Female pupa, in dorsalview (A), ventral view (B), lateral view (C), and ventral view of apex with genital ampulla (D); 13, Male pupa, in dorsal view (A), ventral view (B), and lateral view (C), and ventral view of apex with genital ampulla (D).