Callirhinus Blanchard, 1851

(Figs 1, 5–14)

Type species: Callirhinus metallescens Blanchard, 1851: 176 .

By monotypy. Callirhinus Blanchard in: Blanchard 1851: 176 [catalogue]; Burmeister 1855: 494, 495 [catalogue]; Lacordaire 1856: 337 [hist. nat.]; Bates 1888: 260 [catalogue]; Casey 1915: 67 [key, revision]; Ohaus 1918: 155 [catalogue]; Blackwelder 1944: 246 [checklist]; Machatschke 1957: 178–179 [key, catalogue]; Machatschke 1972: 253 [catalogue]; Potts 1974: 152 [fauna]; Morón 1994: 12, 13 [rarity]; Morón and Hernández-Rodríguez 1996: 106–109 [hist. nat.]; Morón et al. 1997: 47, 48, 124 [fauna]; Delgado et al. 2000: 45, 84 [key]; Jameson et al. 2003: 424, 429 [key, hist. nat.]; Jameson et al. 2007: 433 [biology, phylogeny]; Ramírez-Ponce and Morón 2009: 369 [key, phylogeny]; Morón and Ramírez-Ponce 2012: 108 [taxonomy].

Description: Length 8.03–14.05 mm; width 3.86–6.22 mm. Form: elongate oval, robust, pygidium exposed beyond elytra; dorsum depressed, glabrous. Colour variable; completely navy to black or contrastingly colourful, with head and pronotum green or metallic blue; elytra completely orange or just the anterior half (Fig. 8); venter and legs orange. Sexual dimorphism in protibia and protarsomeres. Head (Figs 5A, 6I, 10–14C, D): clypeus subtriangular, apex constricted, elongate, attenuate, strongly reflexed; punctate-striate, punctures big, deep, contiguous. Frons flat or weakly concave; surface rugopunctate, punctures deep, irregular, contiguous. Supraocular area setose; 5–8 long yellowish setae, decumbent inward (Fig. 6I). Frontoclypeal suture complete, almost straight or weekly bisinuate. Eye canthus wide, deeply rugopunctate; setose, setae abundant, short, erect. Interocular width equals 3.0–5.2 transverse eye diameters. Antenna nine-segmented, club subequal to or shorter in length than antennomeres 1–6. Labrum subtrapezoidal, not visible in dorsal view (Fig. 6H). Mandible rounded externally, apical lobe angulate, inner apex bidentate (upper denticles shorter); molar region with 8–11 lamellae (Fig. 6F). Maxilla with six slender and acute teeth; lacinia rounded externally; palpus with four palpomeres, terminal palpomere subequal or longer than segments 1–3 combined (Fig. 6G). Mentum surface convex, apex deeply bisinuate; subequal width-length ratio; submentum setose; setae long, decumbent forward; terminal palpomere shorter in length to segments 1–2 combined (Fig. 6E). Pronotum (Figs 1A, 10– 14E): widest at middle or at base; base narrower than elytral humeri; anterior margin membranous, beaded complete; posterior margin broadly rounded, bead complete. Disc moderately or slightly convex. Surface glabrous, variably punctate, punctures deep or shallow, rounded or transverse. Scutellar shield: subtriangular, apex acute, wider than long, surface irregularly punctate. Mesepimeron: exposed beyond laterad base of elytra (Fig. 6K). Elytra: surface with 9–11 punctate striae; definition and punctures variable. Epipleuron extends to metacoxa or 2nd ventrite, very wide (dorsal view); ventral surface sparsely and irregularly setose, setae short. Lateral margin rounded. Calla humeral and apical prominent. Elytral suture raised from posterior half to apex. Apex spiniform. Propygidium: partially visible dorsally. Pygidium: width 1.5 times length at middle. Shape subtriangular, widely rounded at apex (caudal view), strongly convex in apical half (lateral view). Surface densely imbricate, sparse and uniformly setose; setae short, wide, decumbent towards apex (Figs 10–14 G). Venter (Figs 10–14A): prosternal process small, subtriangular (Fig. 6J). Mesometaventral process wide, rounded, produced beyond the apex of mesocoxae. Abdominal ventrite 5 longer than any of the preceding ones, external border entire (both sexes). Surface punctate and setose; punctures variable, not deep; setae short, decumbent towards apex, denser on sides forming strands (generally glabrous the central area). Legs (Figs 10–14H–L): protibia with two external teeth; apical teeth longer; subapical spur on inner margin short, not reaching the inner apical margin. Male protarsomere 5 large (subequal or even longer to protarsomeres 1–4); protarsomeres 1–4 subequal or shorter progressively, protarsomere 4 wider than the preceding ones; surface of ventral side of protarsomeres 1–4 with longitudinal keels; internobasal protuberance small, with two long spine-like setae. Male inner protarsal claw deep and widely split; proximal ramus three or four times wider than distal ramus. Unguitractor plate laterally flattened, bisetose; onychium elongate, ventral setae very small. Mesotibia widest at middle, weakly expanded at apex; two oblique carinae; the proximal not complete, with 4–5 strong spines; the distal entire, with 6–8 strong spines; apex with 6–9 spines, spurs variable in length. Mesotarsomeres 1–4 with two long thick hair-like setae on dorsal side (very thin on tarsomere 4), and three spine-like setae progressively thicker on ventral side. Mesotarsomere 5 large (subequal to mesotarsomeres 1–4); internobasal protuberance well developed, with two long hair-like setae. Mesotarsal claws subequal to mesotarsomere 5; outer claw split, proximal ramus three times wider than distal ramus. Unguitractor plate laterally flattened, onychium with one long setae. Metatibia robust, thick (almost uniform), and preapical constriction on dorsal side; two oblique carinae; the proximal not complete, with 3–6 strong spines; the distal entire, with 7–9 strong spines; apex with 10–16 spines, spurs variable in length. Metatarsomeres 1–4 with two long thick hair-like setae on external side (very thin in 4th tarsomere), and three spine-like setae progressively thicker, and one mesoapical patch of small setae in tarsomeres 1–3 or 1–4 on internal side (Fig. 6L); internobasal protuberance well developed, with two long hair-like setae. Metatarsal claws simple, almost subequal to metatarsomere 5. Unguitractor plate laterally flattened, onychium with one long setae. Hind wing (Fig. 6D): elongate, width-length ratio 2.9–3.0:1.0. Posterior margin with well delimited lobes. Contrasting colour; distal half darkened. Anal and jugal field reduced, apical field rounded. Jugal vein not developed. Vein AP3 + 4 poorly sclerotized, slightly curved. AA with base short previous curve. Vein AA1 + 2 not evident. Parameres (Fig. 9A–F): perpendicular to the tectum (lateral view). Subtriangular-elongated (width-length ratio 1.0–1.15:1.0), symmetrical, free (fronto-distal view), apices separated by a preapical notch, straight or slightly curved inward. Surface sparsely setose on distal half (in dorsal and ventral sides). Ventral plate elongated, triangular, apex acute, visible through the middle of parameres (fronto-distal view); surface simple (not ornate), concave (Fig. 6B). Spiculum gastrale: T-shaped, sclerites well developed; elongated setae on external edge (Fig. 6C).

Type locality: ‘Mexico’, with no additional information.

Diagnosis: Body robust, depressed (Fig. 8); clypeus narrowed toward apex and distally curved (Fig. 6I); six maxillary teeth (Fig. 6G); pronotum with anterior and posterior margins complete; apex of elytral suture spiniform; mesometaventral space wide and prominent.

Etymology: Blanchard (1851) does not mention the etymology, but considering the most diagnostic character of this taxon, the name could come from the Greek superlative kalos ‘beautiful’ (derived noun kallos ‘beauty’, usual combining form in Greek kalli - ‘beautiful’), and the Greek word rhino ‘nose’ (of unknown origin), meaning beautiful nose, alluding to the reduced, fine, widely reflexed and upturned clypeus.

Distribution: Central, western, and south of México (Fig. 15). The distribution of the genus, mainly in central and western Mexico, largely coincides with the biogeographic province of the Transmexican Volcanic Belt (TVB) (Morrone et al. 2017), with the exception of the species distributed in southern Oaxaca.

Natural history: This genus inhabits dry deciduous tropical forest, semi-evergreen forest, warm oak forest, secondary plant communities, and sugar cane crops located between 300–2550 m a.s.l. Adults are diurnal and feed on foliage, including of exotic plants like Hibiscus Linnaeus and Saccharum officinarum Linnaeus (Morón and Hernández-Rodríguez 1996), and a variety of ruderal plants (Morón et al. 1997). Precise information about the native plants on which it feeds and copulates are scarce, but we have records of its activity in grasses of the genus Bouteloua Lagasca (Fig 7A, B), the centre of origin of which has been suggested to be Mexico (Herrera-Arrieta 2020).

Taxonomic comments: The information recorded about the origin of the type specimens in the historic ‘Catalogue des Animaux Articulés’ of the MNHN shows for the Series 1844, number 2 (green rounded label with ‘2, 44’): ‘Insects of different orders sent from Mexico by M. Giesbreght (translated from French)’, as cited in the original description by Blanchard (1851). Burmeister (1855) placed Callirhinus into Anisopliina Burmeister, 1844 (‘Anisopliadae’, original spelling), a proposal that has been accepted in the most important studies of the tribe (Ohaus 1918, Machatschke 1957, 1972, Potts 1974, Jameson et al. 2003). Also, it has been considered as an ancient relictual taxon (Morón 1994), but phylogenetic evidence indicates unclear affinities. Paucar-Cabrera (2003), with a small sample of genera, suggests a relationship with Anisoplia Schönherr, but Jameson et al. (2007) found the conflicting hypothesis: Callirhinus as a member of Anisopliina or as its sister group.

Sexual dimorphism: Female similar to male except in the following respects: body wider at humeral calli; antennal club shorter, similar or shorter than pedicel and funiculus together; distal protibial denticle longer and thinner; basal protarsomere markedly elongated; tarsomeres 1–4 thin; internal protarsal claw with the lower ramus subequal or slightly thicker than the upper one.

Taxonomic key

1 Pronotum with external borders converging after lateral angle; surface with shallow punctation(Fig.13E, F). Mesometaventral projection not surpassing the mid-mesocoxa, slender (Fig. 13A), not visible in lateral view (Fig. 13B). Parameres apically forceps-like, apex acute (Fig. 9E). South of Oaxaca .................................................................................................. C. huiinis sp. nov.

2 Pronotum with external borders subparallel or diverging after lateral angle; surface with deep punctation. Mesometaventral projection surpassing the mid-mesocoxa, not slender, visible in lateral view (Fig. 11B). Parameres variable but not as above (except for C. choperi, that has forcep-like parameres but with apex rounded) .................................................................................2

3 Pronotum with lateral margins divergent; surface very dense and deeply punctuated (punctures separated by less than one point diameter) (Fig. 11E, F). Mesometaventral projection very wide and rounded (Fig. 11A). Protibia with apical denticle elongate (Fig. 11H). Mesotibia with apex not widened (Fig. 11K). Parameres apically forceps-like, apex rounded (Fig. 9C). Guerrero, Michoacán, and State of Mexico ................................................................................................................ C. choperi sp. nov.

4 Pronotum with lateral margins subparallel (Fig. 10E); surface with shallow and dispersed punctation (punctures separated by 1.5–3.0 point diameters) (Fig. 12F). Mesometaventral projection wide. Protibia with apical denticles not elongate (Fig. 10H, 12H). Mesotibia with apex slightly widened (Fig. 10K). Parameres not forceps-like (Fig. 9A, B, D, F)...........................3

5 Pronotum finely punctate (punctures separated by 2.5–3.0 point diameters) (Fig. 12F). Parameres short, clearly wider than long, with a conspicuous preapical notch (Fig. 9D). Hidalgo ................................................................................. C. nandu sp. nov.6 Pronotum not finely punctate (punctures separated between 1.5–2.0 point diameters). Parameres elongated, wider than long, with a discrete preapical notch (Fig. 9A, F)....................................................................................................................................4 7 Clypeus wide (Fig. 10C). Protarsomere 4 with interno-mesial lobe notably increased (Fig. 10I). Colima, Guanajuato, Jalisco, Michoacán ................................................................................................................................................. C. metallescens Blanchard 8 Clypeus narrow (Fig. 14C). Protarsomere 4 with interno-mesial lobe not increased (Fig. 14I). Nayarit ..................................... ............................................................................................................................................................................................... C. veeme sp. nov.