Inca LePeletier & Serville, 1828

Sousa, Rafael & Seidel, Matthias, 2021, Review of the Inca irroratus species group with description of two new species of Inca LePeletier & Serville, 1828 (Coleoptera, Scarabaeidae, Cetoniinae), European Journal of Taxonomy 748 (1), pp. 15-35 : 18-21

Genus Inca LePeletier & Serville, 1828

Inca LePeletier & Serville, 1828: 380 .

Ynca – Chevrolat 1833: unpaginated (unjustified emendation).

Inca – Seidel et al. 2018: 389 (checklist, nomenclature).

Type species

Cetonia ynca Weber, 1801 , designated by Howden (1968: 12).

Diagnosis

The genus can be distinguished from other genera of Incini by the following combination of characters: dorsal surface of pronotum covered with waxy velvet like secretion and setigerous punctures with waxy macula (waxy secretion absent in Archedinus , Coelocratus , Golinca and Pantodinus ); clypeus of male with divergent lateral horns (parallel horns in Golinca ; median horn in Pantodinus ; absent in Archedinus and Coelocratus ) with inner area densely setose.

Redescription

Male

BODY. Length including the clypeal horns 23–60 mm; width across humeri 10–21 mm. Surface of pronotum, scutellar shield, elytra and pygidium covered with waxy, velvet like secretion and setigerous punctures with waxy macula.

HEAD. Surface of frons with waxy secretion on disc and setigerous and heterogeneous punctures with light yellow waxy macula; short yellowish setae near to supraocular area; lateral portion of epistomal suture distinct near to canthus. Canthus angulate. Clypeus densely punctate with posterior dorsal margin projecting forward; distal area with divergent lateral horns slightly projecting forward and upward; inner area of horns densely setose, setae long and yellow. Labrum transverse. Mandibles with molar lobe rounded and striated; right molar lobe convex; left molar lobe concave. Maxillae setose; cardo with proximal area densely punctate with long yellow setae; galea inwards projected and with brushlike setae. Hypopharynx with long setae. Labium transverse, deeply and densely punctate; punctures with long yellow setae; anterior margin of mentum emarginated. Antennae with 10 antennomeres; club fusiform composed of three antennomeres.

THORAX. Pronotal surface convex, disc with a longitudinal groove; densely punctate and with short yellow setae; lateral margin sinuated and irregularly crenulated. Hypomeron densely punctate; anterior area with irregular striated punctures. Anterior prosternal process projected (except in I. besckii and I. bonplandi ). Metaventrite densely setose except in the discrimen area. Elytra densely punctate and maculate; elytral striae barely distinct; distal angle acuminate.

LEGS. Profemur with an inner distal tooth. Protibia with a posterior distal tooth and an inner proximal emargination; spur short. Protarsomeres II–IV with inner striae. Mesotibia with one short and bifurcate spur; transversal carina I with stout setae. Outer posterior angle of metacoxa rounded. Metatibia with transversal carina I with stout setae.

ABDOMEN. Spiracle VII placed near to anterior margin of sternite. Sternite VIII (last exposed sternite) with a rounded fovea on anteriomedian area. Propygidium totally or partially covered by resting elytra. Pygidium posterior margin parabolic.

TERMINALIA. Aedeagus: apodeme of phallobase larger than phallobase. Parameres glabrous and with an outer distal process.

Female

BODY. Length 27–50 mm; width across humeri 10–17 mm. The morphology of females of Inca is very similar to the male, except by: posterior area of frons with waxy secretion. Clypeus without horns; anterior angles rounded; frontal area elongated. Outer teeth of protibia larger than in males. Transversal carinae I of meso- and metatibia well-marked; mesotibia with two long and simple spurs. Paraproct distinct.

Remarks

As observed in some works (e.g., Ricchiardi 2002; Morón & Vaz-de-Mello 2007; Seidel et al. 2018), the species of Inca can be distinguished from the other members of the tribe Incini mainly by the male with divergent lateral horns with internal face densely setose with long setae and elytra with yellow waxy maculae. In the brachycerous males the outer angles of clypeal horn can be indistinct in some species.

Distribution

From Tamaulipas in Mexico to Paraguay and northern Argentina.

Key to the species of Inca

1. Clypeal horn present (male)............................................................................................................... 2

‒ Clypeal horn absent (female)........................................................................................................... 10

2. Dorsolateral margin of clypeal horn with a long tooth...................................................................... 3

‒ Dorsolateral margin of clypeal horn without a long tooth................................................................. 4

3. Inner dorsal carina of clypeal horn abruptly interrupted at apex. Elytral disc with large waxy maculae. Outer distal process of parameres long and acuminate. Brazil (São Paulo, Paraná and Santa Catarina ) ( Figs 1A–E, P , 4A )....................................................................................................... I. axeli sp nov.

‒ Inner dorsal carina of clypeal horn gradually interrupted at apeX. Elytral disc without large waXy maculae. Outer distal process of parameres long and rounded. Brazil (Espírito Santo, Minas Gerais and Rio de Janeiro) ( Figs 1F–J, Q , 4B ) ............................................................... I. neglectus sp. nov.

4. Posterior tooth of protibia short and rounded. Posterior angles of pronotum rounded. Brazil (Rio de Janeiro) ( Fig. 1K–O, R ) .......................................................................... I. irroratus Chevrolat, 1833

‒ Posterior tooth of protibia long and acute or short and rounded. Posterior angles of pronotum acuminate........................................................................................................................................... 5

5. Clypeal horn with proximal emargination. Posterior tooth of protibia short and rounded................ 6

‒ Clypeal horn without proXimal emargination. Posterior tooth of protibial long and acute............... 7

6. Inner dorsal carina of clypeal horn distinct. Legs without red reflections. Brazil (Minas Gerais, Rio de Janeiro, Paraná, Santa Catarina and Rio Grande do Sul) ( Fig. 4H )................................................ ................................................................................................ I. besckii Burmeister & Schaum, 1840

‒ Inner dorsal carina of clypeal horn indistinct. Legs with red reflections. Argentina, Bolivia, Brazil and Paraguay ( Fig. 4G )....................................................................... I. bonplandi (Gyllenhal, 1817)

7. Medial and lateral area of pronotum and pygidium without yellow longitudinal bands. Brazil, Argentina, Paraguay ( Fig. 4F ) .......................................................... I. pulverulentus (Olivier, 1789)

‒ Medial and lateral area of pronotum and pygidium with yellow longitudinal bands ( I. clathratus )...8

8. Inner dorsal carina of clypeal horn abruptly interrupted at apex. Trinidad ( Fig. 4E ).......................... .................................................................................... I. clathratus quesneli Boos & Ratcliffe, 1985

‒ Inner dorsal carina of clypeal horns gradually interrupted at apeX.................................................... 9

9. Inner dorsal carina convergent to the inner apical angle. Mexico, Guatemala, Belize, Honduras, Nicaragua, Costa Rica, Panama, Colombia and Ecuador ( Fig.4C ) ..................................................... .............................................................................................. I. clathratus sommeri Westwood, 1844

‒ Inner dorsal carina convergent to the outer apical angle. Colombia, Brazil, Ecuador, Guyana, Suriname, French Guyana, Peru, Bolivia and Argentina ( Fig. 4D ) ..................................................... .............................................................................................. I. clathratus clathratus (Olivier, 1792)

10. Anterior margin of clypeus with a medial tooth...............................................................................11

‒ Anterior margin of clypeus without a medial tooth......................................................................... 14

11. Medial tooth of the anterior margin rounded................................................................................... 12

‒ Medial tooth of the anterior margin acute ....................................................................................... 17

12. Disc of clypeus with a large fovea. Lateral margin of pronotum with deep crenulation. Marks of medial area of elytral epipleuron evident. Brazil (Rio de Janeiro) ( Figs 2I–K, O , 3C, F ) .................. ................................................................................................................ I. irroratus Chevrolat, 1833

‒ Clypeus without fovea. Lateral margin of pronotum with shallow crenulation. Marks of medial area of elytral epipleuron indistinct......................................................................................................... 13

13. Medial tooth of anterior margin of clypeus evident. Elytral disc with large waxy maculae. Brazil (São Paulo, Paraná and Santa Catarina ) ( Figs 2A–C, M , 3A, D )................................ I. axeli sp nov.

‒ Medial tooth of anterior margin of clypeus almost indistinct. Elytral disc without large waXy maculae. Brazil (Espírito Santo, Minas Gerais and Rio de Janeiro) ( Figs 2E–G, N , 3B, E ) .............................. ............................................................................................................................. I. neglectus sp. nov.

14. Pronotum and pygidium densely maculate without yellow longitudinal bands. Brazil, Argentina, Paraguay ( Fig. 4F ) ............................................................................ I. pulverulentus (Olivier, 1789)

‒ Pronotum and pygidium weakly maculate with medial and lateral areas with yellow longitudinal bands ( I. clathratus )......................................................................................................................... 15

15. Widely distributed in Mexico and Central America and restricted to South America on the east side of the Andes Mountains in Colombia and Ecuador.............. I. clathratus sommeri Westwood, 1844

‒ Distributed in South America, on the west side of the Andes Mountains ...................................... 16 *

16. Restricted to Trinidad................................................. I. clathratus quesneli Boos & Ratcliffe, 1985

‒ Distributed in Colombia, Brazil, Ecuador, Guyana, French Guyana, Peru, Bolivia and Argentina.............................................................................. I. clathratus clathratus (Olivier, 1792)

17. Legs without red reflections. Brazil (Minas Gerais, Rio de Janeiro, Paraná, Santa Catarina and Rio Grande do Sul) ( Fig. 4H ) ........................................................ I. besckii Burmeister & Schaum, 1840

‒ Legs with red reflections. Argentina, Bolivia, Brazil and Paraguay... I. bonplandi (Gyllenhal, 1817)

* Step 16 separates the females of I. clathratus s. str. to I. clathratus quesneli . However, the morphology of these species is not informative for the distinction of these taxa. Beyond geographic distribution the females of I. clathratus quesneli are usually bigger than I. clathratus s. str. and can have bluish black tegument coloration beyond the dark green, black or brownish black coloration of I. clathratus s. str. Further studies are needed to better clarify the taxonomy of these species.

Figures

Fig. 1. Males of Inca spp. A–E, P. Inca axeli sp. nov., holotype (MZSP 22036). – F–J, Q. Inca neglectus sp. nov., paratype (MZSP). – K–O, R. Inca irroratus Chevrolat, 1833, neotype (BMNH). A, F, K. Dorsal habitus. B, G, L. Ventral habitus. C, H, M. Lateral habitus. D, I, N. Dorsal view of aedeagus. E, J, O. Lateral view of aedeagus. P–R. Dorsal view of head. Scale bars = 5 mm.

Fig. 4. Images of liveInca spp.A. Inca axelisp. nov. (photo by R. Barros and R. Koike).B. Inca neglectus sp. nov. (photo by N. Marchito). C. Inca clathratus sommeri Westwood, 1844 (photo by A. González Gallina). D. Inca clathratus clathratus (Olivier, 1792) (photo by R. Barros and R. Koike). E. Inca clathratus quesneli Boos & Ratcliffe, 1985 (photo by M. Hulme). F. Inca pulverulentus (Olivier, 1789) mating (photo by R. Barros and R. Koike). G. Inca bonplandi (Gyllenhal, 1817) (photo by J. Touroult). H. Inca besckii Burmeister & Schaum, 1840 feeding on tree sap (photo by N. Wisnik).

Fig. 2. Females of Inca spp. and type labels. A–D, M. Inca axeli sp. nov. – E–H, N. Inca neglectus sp. nov. –I–L, O. Inca irroratus Chevrolat, 1833. A, E, I. Dorsal habitus. B, F, J. Ventral habitus. C, G, K. Lateral habitus. D, H, L. Type labels. M–O. Frontal view of head. Scale bars = 5 mm.

Fig. 3. Morphological details of Inca spp. A, D, G–N. I. axeli sp. nov. (A, D: ♀, G–N ♂). – B, E. I. neglectus sp. nov. – C, F. I. irroratus Chevrolat, 1833. A–C. Protibia, lateral view. D–F. Details of elytral epipleuron. G–N. Mouthparts. G–I. Right mandibles (dorsal, inner and ventral view). J–K. Labrum (dorsal and frontal view). L. Right maxilla (dorsal view). M. Epipharynx. N. Labium.