Taenioderini Krikken, 1984

Vendl, Tomáš, VONDRÁýEK, Dominik, Kubá, VítČzslav & Šípek, Petr, 2014, Immature stages of Taenioderini (Coleoptera: Scarabaeidae: Cetoniinae): a report of hidden morphological diversity, Acta Entomologica Musei Nationalis Pragae 54 (2), pp. 571-604 : 574-576

Tribe Taenioderini Krikken, 1984

Diagnosis of Taenioderini based on larval characters. Larva scarabaeiform, cranium yellowish, pale brown or reddish-brown, body whitish. Abdominal segments IX and X fused dorsally, ventrally separated by incomplete groove.

Head capsule ( Fig. 3 ). Surface of cranium glabrous or with weak microsculpture, yellowish, pale brown or red-brown; antennifer, postclypeus and labrum darker; area around frontoclypeal suture and apices of mandibles usually black. Epicranial suture extending between frontal suture; frontal sutures more or less bisinuate. Epicranial insertions of antennal muscles indistinct, feebly developed or apparent. Anterior and exterior frontal setae minute or absent. Clypeus subtrapezoidal to rectangular, membranous anteclypeal part narrow, not wider than 1/3 of entire clypeal area. Postclypeus sclerotized, with one anterior and one exterior clypeal setae. Stemmata present, well developed.

Antennae ( Figs 3 ; 9E–L ). Tetramerous (an I–IV), relative length of antennomeres (an): an I> an IV> an II> an III or an I Ŀ an IV> an II> an III; an I about as long as an II and an III combined or slightly longer. Ventro-apical projection of ANIII with single sensory spot. An IV with numerous dorsal and ventral sensory spots and single apical sensoric ¿eld.

Labrum. Symmetrical, anterior margin trilobed with numerous setae. Clithra present. Dorsal surface with two transverse rows of setae and additional pair of exterior labral setae on each side.

Epipharynx ( Figs 4A–H ; 12A–F ). Haptomerum: Zygum convex, with arcuate or angulate row of approximately 15 stout setae and several similar setae on mesal margin. Sensilla of zygum grouped in two groups distad to the row of stout setae, or in single ¿eld on a more or less projecting cone. Haptomeral process and proplegmata absent.Acroparia: External margin of medial labral lobe with four to ¿ve long setae on ventral side and three to four setae on dorsal side. Lateral labral lobes with three to seven long setae. Setae of acanthoparia on a more or less distinct tubercle, increasing in size towards apex. Plegmata absent. Chaetoparia asymmetric, setae in more or less distinct longitudinal rows or irregularly scattered on chaetoparia, medial rows with stout, spine-like setae. Dexiotorma straight, robust or narrowed, right pternotorma present or widely reduced. Laeotorma usually reduced (entirelly developed only in Chalcothea neglecta Ritsema, 1882 and Plectrona tristis ), left pternotorma triangular or rectangular, large. Haptolachus: Sense cone well developed or reduced to low cob-like tubercle, sclerotized plate (right nesium) absent. Plate-shaped sclerite present. Haptolachus posteriad with two pairs of pore-like setae on each side. Phoba and crepis absent.

Mandibles ( Figs 6A–O ; 7A–O ; 8A–O ; 9A–C ; 13F–L ). Asymmetrical, dorsomolar and ventromolar setae present on both mandibles, stridulatory area absent in P. tristis , strongly reduced in C. neglecta , in all other species consists of about 20 transversal ridges. Left mandible with four, right mandible with three scissorial teeth.

Maxilla ( Figs 5 ; 12G–M ). Dorsomedial surface of stipes with oblique row of more than ¿ve well sclerotized spine-shaped or drop-shaped stridulatory teeth and anterior truncate process (blunt tubercle, Fig. 12M ). Galea and lacina entirely fused forming mala, galeo-lacinial suture indistinct, entirely absent on ventral face. Galear portion of mala with single falcate uncus and several long and stout hair-like setae in longitudinal rows; lacinia with one or two unci, subapical uncus, if present, small and indistinct. Maxillary palpi tetramerous, penultimate palpomere with two setae.

Hypopharyngeal sclerome ( Figs 5 ; 12N–O ). Asymmetrical with strong protruding hypopharyngeal process. Tufts of tegumentary expansions (= phoba, sensu BÖVING 1936) present on left lateral lobe. Tegumentary expansions of right central part of scleroma either present, absent or individually variable (e.g. present in one specimen, absent in another).

Ligula ( Figs 5 ; 13A–E ). Dorsal surface with group of approximately 10–15 hair-like setae on each side; paramedial longitudinal row of three to ¿ve stout setae and proximal transverse row of several campaniform or conical setae. Labial palpi bimerous.

Thorax ( Figs 2A–H ). Prothorax with single dorsal lobe, meso- and metathorax with three well developed lobes. Each dorsal sublobe of thoracic segments with one row of medium long to long setae along with several short setae irregularly scattered anterior to the row. Prothoracic sclerite covering almost whole lateral portion of prothorax. Mesothoracic spiracle ( Figs 6P–T ; 7P–R ) with C-shaped respiratory plate; bullar opening constricted or wide open. All pairs of legs ( Figs 9M–T ) subequal. Pretarsi conical to cylindrical in shape with two setae, claw present or greatly reduced ( Figs 7S–T ; 8P–T ; 9D ).

Abdomen ( Figs 2A–H ; 10 ; 11 ). Nine-segmented. Abdominal segments IX and X fused, fusion line is visible on the ventral side. Dorsa of abdominal segments I–VI with three, segments VII and VIII with two sublobes respectively. Each sublobe bearing one to three (four) rows of setae. Setae in anterior rows short, posterior row with distinctly longer setae.

Abdominal pilosity often species-speci¿c, from long hair-like setae ( Euselates laoticus Mikšiü, 1974 ) to long stout ( Chalcothea neglecta ), spatulate (long or short; Coilodera diardi (Gory & Percheron, 1833) , E. cineraceus (Gory & Percheron, 1833)) to hamate ( Coilodera penicillata ). Abdominal spiracles similar to mesothoracic spiracle, but smaller. Ultimate abdominal segment usually densely setose. Anal slit transverse.

Raster ( Fig. 10 ). Palidium present or absent, if present than monostichous (few irregular pali may be scattered around main row), composed of approximately 10–22 pali arranged in single U-shaped row or two parallel rows respectively. Septula opened posteriorly.

Figures

Fig. 3. Third instar larvae of Taenioderini. A–H – cranium. A – Chalcothea neglecta. B – Coilodera diardi. C –C. penicillata. D – Euselates cineraceus. E – E. laoticus. F – Meroloba suturalis. G – Plectrone tristis. H – Taeniodera sp. Scale bars: Figs 3A–H = 1mm.

Fig. 9. Third instar larvae of Taenioderini.A–C – right mandible (ventral, medial and dorsal aspect), D – pretarsus, E–L– antenna (dorsal and ventral aspect), M–T – metathoracic leg: A–D – Taeniodera sp. E,M – Chalcothea neglecta. F,N – Coilodera diardi. G,O – C. penicillata. H,P – Euselates cineraceus. I,Q – E. laoticus. J,R – Meroloba suturalis. K,S – Plectrone tristis. L, T – Taeniodera sp. Scale bars = 1 mm.

Fig. 4. Third instar larvae of Taenioderini. A–H – epipharynx. A – Chalcothea neglecta. B – Coilodera diardi. C – C. penicillata. D – Euselates cineraceus. E – E. laoticus. F – Meroloba suturalis. G – Plectrone tristis. H – Taeniodera sp. Scale bars = 1 mm.

Fig. 12. Third instar larvae of Taenioderini, SEM images.A–C – epipharynx:A – Chalcothea neglecta. B – Coilodera diardi. C– Taeniodera sp. D–F – sense cone (haptolachus, epipharynx): D – Chalcothea neglecta. E – Coilodera diardi. F– Euselates laoticus. G–M – maxillar stridulatory teeth: G – Chalcothea neglecta. H – Coilodera diardi. I – C. penicillata. J – E. cineraceus. K – E. laoticus. L – Meroloba suturalis.M – Taeniodera sp. N,O – hypopharyngeal scleroma: N – E. laoticus. O – Meroloba suturalis.

Fig. 6. Third instar larvae of Taenioderini.A–O – left mandible (dorsal, medial and ventral aspect), P–T – thoracic spiracle. A–C,P – Chalcothea neglecta. D–F,Q – Coilodera diardi. G–I,R – C. penicillata. J–L,S – Euselates cineraceus. M–O,T – E. laoticus. Scale bars: Figs A–O = 1mm; Figs P–T = 0.5 mm.

Fig. 7. Third instar larvae of Taenioderini. A–I – left mandible (dorsal, medial and ventral aspect), J–O – right mandible (ventral, medial and dorsal aspect), P–R – thoracic spiracle, S–T – pretarsus.A–C,P – Meroloba suturalis. D–E,Q – Plectrone tristis. G–I,R – Taeniodera sp. J–L,S – Chalcothea neglecta. M–O,T – Coilodera diardi. Scale bars: Figs A–O,S = 1 mm; Figs P–R = 0.7 mm; Fig. T = 0.1 mm.

Fig. 8. Third instar larvae of Taenioderini.A–O – right mandible (ventral, medial and dorsal aspect), P–T – pretarsus. A–C,P – Coilodera penicillata. D–F,Q – Euselates cineraceus. G–I,R – E. laoticus. J–L,S – Meroloba suturalis. M–O,T – Plectrone tristis. Scale bars: Figs A–P,T = 1 mm; Figs Q–S = 0.5 mm.

Fig. 13. Third instar larvae of Taenioderini, SEM images. A–E – ligula: A – Chalcothea neglecta. B– Coilodera diardi, C – Euselates cineraceus. D – Meroloba suturalis. E – Taeniodera sp. F–L – mandibular stridulatory area: F – Chalcothea neglecta. G – Coilodera diardi. H – C. penicillata. I – E. cineraceus. J – E. laoticus. K – Meroloba suturalis. L – Taeniodera sp.

Fig. 5. Third instar larvae of Taenioderini. A–H – maxillo-labial complex.A – Chalcothea neglecta. B – Coilodera diardi. C – C. penicillata. D – Euselates cineraceus. E – E. laoticus. F – Meroloba suturalis. G – Plectrone tristis. H – Taeniodera sp. Scale bars = 1 mm.

Fig. 2. Third instar larvae of Taenioderini.A–H – habitus.A – Chalcothea neglecta. B – Coilodera diardi. C –C. penicillata. D – Euselates cineraceus. E – E. laoticus. F – Meroloba suturalis. G – Plectrone tristis.H – Taeniodera sp. Figures not to scale.

Fig. 10. Third instar larvae of Taenioderini. A–H – ultimate abdominal segment, ventral aspect. A – Chalcothea ne- glecta. B – Coilodera diardi. C – C. penicillata. D – Eusela- tes cineraceus. E – E. laoticus. F – Meroloba suturalis. G – Plectrone tristis. H – Taenio- dera sp. Scale bars = 1 mm.

Fig. 11. Third instar larvae of Taenioderini. A–H – ultima- te abdominal segment, lateral aspect: A – Chalcothea neglecta. B – Coilodera diardi. C – C. peni- cillata. D – Euselates cineraceus. E – E. laoticus. F – Meroloba suturalis. G – Plectrone tristis. H – Taeniodera sp. Scale bars = 1 mm.