Niponius osorioceps Lewis, 1885

Zaitsev, A. A. & Zaitsev, A. I., 2019, Description of the larva of Niponius osorioceps Lewis, 1885 (Coleoptera: Histeridae) with first data on chaetotaxy of Niponiinae, Russian Entomological Journal 28 (2), pp. 148-157 : 149-156

Niponius osorioceps Lewis, 1885

Figs 2–15 .

MATERIAL. 30 larvae together with pupae and adults: Russia, Southern Primorie , Lazovskyi reserve , Proselochnaya cordon, middle stream of Formozov spring, 43°00’805"N 134°06’424"E, 19.VIII.2007, leg. & det. K. Makarov, A. Zaitsev ( MSPU) .

DESCRIPTION. Last instar larva. Maximum body length about 12 mm; head length 0.9 mm; urogomphi length 0.2 mm; maximum width of thorax 1 mm; maximum width of abdomen 1.1 mm. Body elongated, cylindrical; widest across abdominal segments II–VI, slightly tapering posterad; urogomphi small, 2-jointed. Head capsule brownish-yellow, its low- er part somewhat lighter; mandibles reddish-brown, sclerotized parts of antenna, labial and maxillary palpi light brown. Pronotum yellowish-brown, straw-yellow along the edges. Meso- and metanotum lighter, from brownish-yellow to straw-yellow. Pleurites pale yellow, prothoracic sclerites brownish-yellow, sclerotized parts of legs light brown. Abdominal sclerites pale yellow, barely distinguishable from membrane. Abdominal segments IX–X have the same coloration, only distal urogomphal joints more pigmented, yellowish-brown. Membranous area of thoracic and all abdominal segments except IX–X covered in numerous short asperities. Tergite of abdominal segment I with a pair of heavy sclerotized egg bursters. Abdominal segments II–VIII on dorsal and ventral sides with paired ampulla ( Fig. 2 ).

Head capsule (Fig. 3): prognathous, protracted, subrectangular, slightly narrowed posteriorly and deeply emarginat- ed at base. Dorsal surface of each parietal sclerite with concave area which marked by sclerotized ridge; epicranial suture rather long, about 0.2 as long as head capsule; frontal sutures short, V-shaped. Ventral tentorial pits confluent at middle forming tentorial fossa. Stemmata absent.

Chaetotaxy of head capsule (Fig. 3). Frontal sclerite on each side with 11 separate setae: 8 microsetae (FR1–FR7, FR9) and 3 mesosetae (FR8, FR10–11); one setal group of 5 mesosetae (gFR) located on anterolateral margin. Also 5 pores present (FRa–FRd, FRf). Nasale (Fig. 4) asymmetrical, with 2 small teeth, each with microseta and 1 larger teeth with 2 microsetae. Also a pair of subfrontal mesosetae (SF) locat- ed ventrally near each lateral margin of nasale. Each parietal sclerite dorsally with 11 setae: 5 microsetae (PA12–PA14, PA16–PA20), mesoseta PA15 and 2 macrosetae (PA21–22); also 3 pores present (PAg–PAi). Ventrally each parietal sclerite with 8 setae: 2 microsetae (PA28–29), 4 mesosetae (PA24, PA26–27, PA30) and 2 macrosetae (PA23, PA25); also 7 pores present (PAl, PAn; PAo–PAs).

Antenna (Fig. 6) with 3 antennomeres, about 0.6 as long as greatest head width. Antennomere I 1.9 as long as wide, its sclerotized area with 4 pores: ANa, ANc near inner edge; ANb, ANd near outer edge. Antennomere II 0.8 as long as antennomere I and about 1.8 as long as wide, with single pore ANe on sclerotized area; distal membrane with 2 conical sensoria (SE1–2) and 5 papillate sensilla, 3 located on outer edge close to SE2, and other 2 on inner edge near the base of antennomere III. Antennomere III 0.5 as long as antennomere II and twice as long as wide, its apex with 2 small and 3 larger papillate sensilla surrounding conical sensorium.

Mandible (Fig. 5) narrowed, falcate, 1.8 as long as basal width, unidentate, incisor area with well developed retinaculum. Macroseta MN1 located one third from base, vestigal seta MN2 located dorsally near apex, group of penicillus setae (PE) with 9 long plumose setae and 3 shorter nonplumose setae. Also 3 pores present: MNa located dorsally approximately in the middle of the mandible, MNb — dorsolaterally from MNa, MNc — near the base of retinaculum.

Maxilla (Fig.7). Stipes 1.8 as long as wide, with 6 setae ( MX 1–6), setal group (gMX1) and 4 pores (MXa–d): microseta MX 1 on inner edge near the base of stipes; 3 mesosetae: MX 2 located ventrally one third from base, MX 5–6 dorsally on distal membrane; 2 macrosetae: MX 3 located ventrally two third from base, MX 4 ventrally on outer edge, near distal membrane; gMX1 consists of 10 plumose setae on inner edge. Distal membrane of stipes with 4 dorsal elongated spines (flexible nonplumose setae sensu Kovarik and Passoa [1993]). Pores MXa–b, MXd ventral, pore MXc dorsal, all located on sclerotized part of stipes. Palpifer 1.1 as long as wide, with single macroseta MX 7 ventral on outer edge; 2 pores (MXe–f) and 2 elongated spines dorsal on distal membrane. Galea about 4 as long as wide with 2 apical setae: mesoseta MX 8 dorsal and microseta MX 9 ventral. Palpomere I 0.6 as long as palpifer, almost as long as wide, with single ventral pore MXg. Palpomere II 0.8 as long as palpomere I, almost as long as wide, with single ventral pore MXh and 4 pore-like sensilla. Palpomere III almost as long as palpomere II, about 1.7 as long as wide, dorsally with digitiform sensilla (SD), ventrally with 2 pore-like sensilla; its apex with 8 short basiconical sensilla.

Labium (Fig.7). Mentum reduced, its distal part membranous, dorsally with group of about 20 plumose setae (gLA); proximal part sclerotized. Prementum almost as long as wide, base of dorsal surface with numerous teeth; on each side with obtuse spinose lobe bearing 4 teeth, distal one is significantly larger than others. Prementum with 2 setae and 2 pores: macroseta LA2 located ventrally on sclerotized part of prementum near the distal membrane and mesoseta LA3 on dorsal distal membrane; it is possible that seta?LA1 reduced to pore and located dorsally near the base of prementum; LAa situated close to LA2, LAb dorsal on sclerotized part. 3 pore-like and 1 short peg-like sensilla flanking LA3. Labial palpomere I 1.3 as long as wide, with single pore-like sensilla on distal membrane. Palpomere II 1.3 as long as palpomere I, almost 2.5 as long as wide, with digitiform sensilla dorsally and 3 pore-like sensilla on sclerotized part. Its apex with 7 basiconical sensilla, central one is the largest.

Thorax (Fig. 8): about 0.2 as long as total body length, widest across mesothorax. Prothorax is 0.8 as long as wide and 1.2 as long as meso- and metathorax.

Prothorax. Prothoracic tergite (PT) with well sclerotized trapezoidal pronotal shield, medial ecdysial line distinct. Pronotal shield with 10 setae on each side: 4 macrosetae (TE2–3, TE5, TE9), mesoseta TE4 and 5 microsetae (TE1, TE7–8, TE10–11). Also 9 pores present (TEa–i). Rest of PT with 10 setae on each side: 5 macrosetae (TE16, TE18–19, TE21, TE23), 4 microsetae (TE17, TE20, TE24, TE27), seta?TE15 visible as pore. Also 4 pores present (TEj, TEk–m). Each episternite (ES) with 2 microsetae (PL34–35) close to procoxal cavity. Each epimeron (EM) with single microseta ST40. Presternite (PS) roughly quadrate, with 2 microsetae (PR7, PR9) on each side; each lateral presternite (LP) triangular, about twice as long as PS, with 3 microsetae (PR1, PR4–5) and macroseta PR6. Prosternite (ST) diamond-shaped, its central area with smooth cuticle. Each side with 3 setae: mesoseta ST46, 2 microsetae (ST30, ST44). Laterosternites (LS) small, oval, without setae; precoxite not distinct, 2 microsetae (ST31–32) on each side. Short asperities cover the area between each laterosternite and prosternum.

Mesothorax. Mesothoracic tergite (MsT) with well sclerotized roughly rectangular mesonotal shield, medial ecdysial line distinct. Numerous short asperities located on anterior sternum and between humeral and lateral tergites. Mesonotal shield on each side with 2 microsetae (TE10–11) and a single pore TEf. Rest of MsT with 6 setae on each side: 3 macrosetae (TE4–5, TE9), mesoseta TE8 and 2 microsetae (TE3, TE7). Also 2 pores (TEj–h) present. Each humeral tergite (HT) with 4 microsetae (TE1–2, TE13–14) and 4 pores (TEa–c, 1 unassociated pore). Each lateral tergite (LT) with 7 setae: 3 macrosetae (TE16, TE18–19) and 4 microsetae (TE15, TE17, TE20–21). Also a single pore TEj present. Each anterior pleurite (AP) with 2 microsetae (PL23–24). Thoracic spiracle ( Fig. 11 ) surrounded by AP, annular-biforous. Each posterior pleurite (PL) subdivided in 2 plates, anterior without setae, posterior about twice as long and bears macroseta PL27 and microseta PL28. Each ES with 2 microsetae (PL34–35) close to procoxal cavity. Each EM with single microseta ST40. Precoxite not distinct, 2 microsetae present (ST31–32) on each side. LS elongated, much larger than on prothorax, without setae. Mesosternite (ST) roughly oval, with 3 setae on each side: macroseta ST46 and 2 microsetae (ST30, ST44).

Metathorax. Metathoracic tergite (MtT) with well sclerotized rectangular metanotal shield, medial ecdysial line poorly seen. Numerous short asperities located on anterior part of the whole segment. Metanotal shield on each side

7

Figs 3–7. Niponius osorioceps , larva: 3 — head, left — dorsal, right— ventral; 4 — nasale, ventral; 5 — left mandible, dorsal; 6 — right antenna, dorsal; 7 — labio-maxillar complex, left — ventral, right — dorsal. Scale bars: 0.1 mm.

Рис. 3–7. Niponius osorioceps , личинка: 3 — голова, слева — сверху, справа— сниЗу; 4 — наЗале, сниЗу; 5 — леваЯ мандибула, сверху; 6 — праваЯ антенна, сверху; 7 — лабио- максиллЯрный комплекс, слева — сниЗу, справа — сверху. Масштаб: 0.1 мм.

.

мм. 0.5 mm :: 0.5 bar Масштаб Scale I-III. I-III. сегменты segments грудные thoracic,, larva личинка

,, osorioceps osorioceps Niponius Niponius

.. 8 8

.

. Fig Рис with single microseta TE11 and 2 pores (TEf–g). Rest of MtT with 4 setae on each side: macroseta TE9, mesoseta TE8 and 2 microsetae (TE7, TE10); also a single pore TEh present. Humeral tergites very pale, without setae. Dorsolateral tergites (DL) well developed, oval, each with 3 setae: 2 macrosetae (TE4–5) and mesoseta TE3; also a single pore TEi present. Chaetotaxy of the rest metathoracic sclerites is the same as on mesothorax except the absence of TE15 on LT.

Legs short, five-jointed, similar in form and chaetotaxy. Length ratio of its joints to coxa is 0.5:0.8:1.1:1.7. Mesothoracic leg ( Fig. 9 ): coxa with 11 setae: 5 macrosetae (CO11, CO15–16, CO18–19), 3 mesosetae (CO12–14) and 3 microsetae (CO1–3). Pores not visible. Trochanter with microseta TR1, mesoseta TR3 and 4 pores (TRa–b, TRd–e). Femur with 7 mesosetae (FE2–8) and 2 pores (FEa–b). Tibiotarsus with 17 microsetae (TI1–17) and a single pore TIb. A single claw styliform, about 1.4 as long as tibiotarsus, without setae.

9

.

мм. mm 0.5 0.5 bar Масштаб Scale. I-II segments I-II. сегменты abdominal, брюшные larva, личинка

,, osorioceps osorioceps Niponius Niponius

.. 12 12

.

. Fig Рис

Thoracic endoskeleton ( Fig. 10 ): prothorax with poorly-developed episternal and epimeral apodemes; pleural apodeme triangular, narrowed apically, profurcae and spinae absent. Meso- and metathorax with poorly-developed episternal and epimeral apodemes; pleural apodemes reduced; meso- and metathoracic furcae absent, meso- and metathoracic spinae absent. Such simple structure of the thoracic endoskeleton corresponds with other studied representatives of the family.

Abdomen. Abdominal segment I (Fig. 12). Tergum with 9 paired sclerites and 3 single sclerites: median sclerite, sclerite with egg bursters and posterior tergite; on each side with 12 setae and 5 pores. Each sclerite with egg burster bears single mesoseta TE3 and 2 pores: TEb located near egg burster, and TEe adjoined TE3. Large median sclerite with macroseta TE9, mesoseta TE11 and pore TEg adjoined TE9. There are 3 small and 1 medsized sclerites on each side of large median sclerite. Most closely situated small sclerite with single mesoseta TE8; another small sclerite anteriad of TE8 with mesoseta TE6 and adjoined pore TEi; third small sclerite laterad of TE6 with mesoseta TE4. Medsized sclerite with macroseta TE5. Each lateral tergite subdivided into 5 sclerites; the largest one with macroseta TE19, microseta TE20 and pore TEj adjoined TE19. Sclerite located anteriad to TE19 with macroseta TE16; posterior sclerite with mesoseta TE18; the smallest sclerite with mesoseta 21. Sclerite situated laterad of TE18 without setae. Pleuron on each side with 4 sclerites and 6 setae. Anterior pleurite is the largest sclerite with macroseta PL25 and 2 microsetae (PL23–24); lesser sclerite with macroseta PL27 and microseta PL26; the smallest sclerite with mesoseta PL28. Sclerite located between anterior pleurite and spiracle without setae. Sternum on each side with 6 sclerites and 10 setae; also single median sclerite present. Anterior sternite without setae; median sternite with microseta ST46; small sclerite located between anterior and median sternites with microseta ST30. There are 4 sclerites surrounding ventral ampulla: anterior sclerite with 2 microsetae (ST31–32); posterior with 2 macrosetae (ST41, ST43); larger lateral sclerite with macroseta ST40 and microseta ST39; lesser lateral sclerite with 2 microsetae (ST44– 45). Numerous short asperities located mostly in anterior half of the segment.

Abdominal segment II similar to I, but differs in better developed tergal and sternal ampulla; lack of egg bursters; pleuron on each side with additional sclerite without setae; anterior pleurite without PL23; anterior part of sternum with one additional sclerite on each side, without setae; each sclerite, posterior to ventral ampulla subdivided into two, one with ST41, other with ST43. Abdominal spiracles similar to those on thorax, annual-biforous ( Fig. 11 ). Abdominal segments III–VIII like segment II.

Abdominal segment IX ( Figs 13–14 ) without ampulla and asperities. Tergum with 8 setae and 6 sclerites on each side. 2 mesosetae (TE3, TE21) and 2 macrosetae (TE9, TE16) each located on small sclerite; 2 macrosetae (TE5, TE17) both located on midsized sclerite; microseta TE18 and macroseta TE19 both located on a small sclerite. Pleuron with 5 setae and 4 sclerites on each side. Microseta PL24, mesoseta PL28 and macroseta PL25 each located on small sclerite; mesoseta PL26 and macroseta PL27 both located on midsized sclerite. Sternum with 4 setae and 3 sclerites on each side. Microseta ST30 on minute anterior sclerite, mesoseta ST46 on small sclerite; mesoseta ST38 and macroseta ST40 both on midsized sclerite. Urogomphi ( Fig. 15 ) 2-jointed, basal urogomphal sclerites dorsally with microseta UG4, macroseta UG3 and pore?UGa sharing midsized sclerite, and separate mesoseta UG2 closer to urogomphal joint I; ventrally with mesoseta UG5 and macroseta UG6 closer to urogomphal joint I. Urogomphal joint I almost as long as wide, its apical part dorsally with mesoseta UG8 and pores UGc–d on distal membrane, ventrally with 2 macrosetae (UG9–10). Urogomphal joint II 2.5 as long as wide and almost 1.5 as long as urogomphal joint I, its apical part dorsally with macroseta UG12, ventrally with microseta UG11 and macroseta UG13; pore UGe locat- ed dorsally on sclerotized part.

Abdominal segment X ( Fig. 14 ) short, considerably retracted and directed posteroventrally, without asperities, sclerites not distinct. On each side with 8 setae: 2 previously undiscribed apical microsetae; 5 mesosetae (PP1–3, PP5, PP7) and single macroseta PP4 surrounding abdominal segment X. A single pore PPa present in anterolateral part of the segment.

BIOLOGY. Numerous larvae were found crawling in galleries of Hylesinus tristis , feeding on its larvae and pupae.

Figures

Figs 1–2. Niponius osorioceps, habitus: 1 — adult male, dorsal; 2 — larva, lateral. Scale bar: 2.0 mm. Рис. 1–2. Niponius osorioceps, общий вид: 1 — самец, сверху; 2 — личинка, сбоку. Масштаб: 2,0 мм.

Figs 9–11. Niponius osorioceps, larva: 9 — mesothoracic leg, ventral; 10 — thoracic endoskeleton; 11 — thoracic spiracle. Scale bars: 0.1 mm for 9; 0.5 mm for 10; 0.05 mm for 11. Рис. 9–11. Niponius osorioceps, личинка: 9 — нога 2-ой пары, сниЗу; 10 — Эндоскелет грудных сегментов; 11 — грудное дыхальце. Масштаб: 0,1 мм длЯ 9; 0,5 мм длЯ 10; 0,05 мм длЯ 11.

Figs 13–14. Niponius osorioceps, larva: 13 — abdominal segment IX, dorsal; 14 — abdominal segments IX–X, ventral. Scale bar: 0.5 mm for 13–14. Рис. 13–14. Niponius osorioceps, личинка: 13 — IX сегмент брюшка, сверху; 14 — IX и X сегменты брюшка, сниЗу. Масштаб: 0,5 мм длЯ 13–14.

Fig. 15. Niponius osorioceps, larva, right urogomph, dorsal. Scale bar 0.2 mm. Рис. 15. Niponius osorioceps, личинка, праваЯ урогомфа, сверху. Масштаб 0,2 мм.