Callirhinus nandu Ramírez-Ponce & Zaragoza, 2024

Ponce, Andrés Ramírez, Caballero, Santiago Zaragoza & Seidel, Maưhias, 2024, Geometric morphometry enables species hypotheses testing and the assignment of historical type specimens in the genus Callirhinus Blanchard (Coleoptera: Scarabaeidae: Anomalini), Zoological Journal of the Linnean Society 202, pp. 1-26 : 21

Callirhinus nandu Ramírez-Ponce & Zaragoza , sp.nov.

( Figs 8D , 9D , 12 )

ZooBank: urn:lsid:zoobank.org:act:FABBBCA8-D3F0-4132-8A6D-419BA7FC2E17

Type material: Holotype (male, IEXA): (a) ‘ MEXICO: Hidalgo / Apan 4-IX-62 / R. MacGregor, col’., (b) ‘ Callirhinus nandu Ramírez-Ponce & Zaragoza, 2022 HOLOTYPE ♂’ (red label).

Diagnosis: Pronotum with lateral margins subparallel; surface finely punctate (punctures separated by 2.5–3.0 point diameters); mesometaventral projection wide; protibia with apical denticles not elongate; parameres clearly wider than long.

Description: Holotype (male, IEXA): length 9.95 mm; width 4.96 mm. Colour ( Figs. 8D , 12A, B ): head, disc of pronotum, and scutellar shield shiny metallic green; lateral margins of pronotum and elytra yellow; elytral suture, epipleura, venter, and legs reddish brown. Head ( Fig. 12C, D ): frons densely areolate-rugose transverse to punctate toward occipital area; spaces wide and deep. Clypeus with apex slightly curved, reflexed, lateral borders straight, broad-based, short; densely areolate-rugose, spaces rugulose-transverse. Interocular width equals six transverse eye diameters. Antennal club subequal to scape, pedicel and funicle together. Pronotum ( Fig. 12E ): lateral margins slightly divergent (distal half); surface moderately dense and uniformly punctate (separated by a 2.0–3.0 puncture diameter), punctures small, shallow, rounded ( Fig. 12F ). Elytra: surface with 12 punctate striae subparallel; punctures moderate in size and shallow, irregularly contiguous even close to each other (on proximal half); 7 striae on disc, 5 laterad of humerus; dorsal striae 8 very irregularly impressed, incomplete; all striae not mixed; interstriae not raised, sutural striae very slightly raised towards apex, subbasal sinuation weak. Pygidium ( Fig. 12G ): surface imbricate, with moderately long and moderately thick setae, longer and very slender on apex; concavity pronounced in apical third (lateral view). Venter ( Fig. 12A, B ): mesometaventral projection wide, surpassing the mid-mesocoxa, apex rounded and scarcely protruding (lateral view); abdominal ventrites with transverse, regular rows of moderately long, yellowish setae, mesial area almost glabrous. Legs ( Fig. 12 H-L): protibia very wide; upper teeth very short, curved and pointed; protarsomere 5 enlarged, slightly longer than the length of the previous ones combined, internobasal protuberance keel-shaped; protarsomeres 1–4 progressively shorter and widened; protarsomere 4 with interno-mesial lobe not notably increased; protarsomere 1 subequal to 2. Lower ramus of inner claw 3.6 times the width of upper one. Mesotibia widest at middle, weakly expanded at apex; external margin with separate, thick and relatively long spines at base; incomplete oblique carina in basal third (composed of 6–7 relatively long and slender spines), and continuous oblique carina in subapical two-thirds (composed of 10–11 short spines); apex with 8 relatively long spines; apical spurs rounded; internal spine exceeding the middle of mesotarsomere 2, external spur exceeding mesotarsomere 1. Metatibia widest at middle, weakly expanded at apex; external margin with incomplete oblique carina at basal third (composed of 3–4 short spines), and continuous oblique carina in subapical two-thirds (composed of 9–10 spines); apex with 14–15 short spines; internal spine produced near to the half of mesotarsomere 2, external spur subequal to mesotarsomere 1. Metatarsomere 5 subequal to the length of the previous ones combined; internal mesoapical patch of setae present in metatarsomere 4; internal spines on metatarsomere 1 and external ones in metatarsomere 4 thick. Parameres ( Fig. 9D ): wider than long; external margins slightly curved, preapical notch present; apices rounded.

Etymology: From the Otomí denomination ‘ñandú’ (variant of the Mezquital Valley), due to the preponderance of this ethnic group in the state of Hidalgo, Mexico (SEP-INALI 2014).

Distribution: The holotype was collected in Apan, in the state of Hidalgo, Mexico ( Fig. 15 ).

Phenology: September (1).

Natural history: This is the species with the highest distribution recorded in a locality with vegetation of pine, oak, pine-oak forests, and crasicaule scrub around 2500 m a.s.l.

Taxonomic remarks: Callirhinus nandu bears the closest resemblance to C. metallescens both in size and in the form of diagnostic characters such as the pronotum and protibia; however, it has a more abundant vestiture on the venter and the most distinct parameres of all species, which are notably shorter.

Figures

Figure 8. Habitus of Callirhinus spp.: (A, B) Callirhinus metallescens Blanchard; (C) Callirhinus choperi sp. nov; (D) Callirhinus nandu sp. nov., (E) Callirhinus huiinis sp. nov., (F) Callirhinus veeme sp. nov. (Scale bar 2 mm).

Figure 9. Parameres of Callirhinus spp.: (A, B) Callirhinus metallescens Blanchard; (C) Callirhinus choperi sp. nov.; (D) Callirhinus nandu sp. nov., (E) Callirhinus huiinis sp. nov., (F) Callirhinus veeme sp. nov. (Scale bar 0.5 mm).

Figure 12. Callirhinus nandu sp. nov.: (A) ventral habitus, (B) lateral habitus, (C) head, dorsal view, (D) head, oblique view, (E) pronotum, dorsal view, (F) pronotum, punctation detail, (G) pygidium, frontal view, (H) protibia, dorsal view, (I) protarsomeres, lateral view, (J) metatarsomeres, lateral view, (K) mesotibia, ventro-lateral view, (L) metatibia, ventro-lateral view.

Figure 15. Distribution map of the genus Callirhinus Blanchard.