Allorrhina soror Moser, 1911

Ratcliffe, Brett C., 2015, A Revision of the Neotropical Genus Allorrhina Burmeister, 1842 (Coleoptera: Scarabaeidae: Cetoniinae: Gymnetini), The Coleopterists Bulletin 69 (1), pp. 91-113 : 91-113

Allorrhina soror Moser, 1911

( Figs. 35–38 )

Allorrhina soror Moser, 1911b: 531 (original combination).

Lectotype male at ZMHU, labeled: “ Villavicencio, Columbia (sic), 440 m, I–II// soror Mos. // Allorrhina soror Mos. , Type, male symbol//Holotype, male symbol, G. Ruter det. 1964, Allorrhina soror Moser ” and with my red lectotype label. Lectoallotype female at ZMHU with same labels except with female symbol and with my red lectoallotype label. Nine paralectotypes at ZMHU, labeled: “Villavicencio, Columbia (sic)” and with my yellow paralectotype label. One male and one female paralectotype at MNHN with same labels and my yellow paralectotype labels. Lectotypes examined, designated by Ratcliffe (2004).

Description. Length 17.4–22.7 mm; width across humeri 10.3–14.2 mm. Clypeus, elytral suture, legs, and venter reddish brown to piceous, shiny. Frons, pronotum, elytra, and pygidium opaque, light to dark reddish brown, lacking cretaceous marks. Setae of venter and legs in males tawny, females with tawny and black setae mixed. Head: Clypeus of males deeply concave, with moderately large, moderately dense, setigerous punctures; setae long, dense, tawny; lateral margins elevated, subparallel, keel-like; clypeal apex with horn short, stout, subquadrate, projecting forward and obliquely upwards, apex weakly emarginate; occipital horn dorso-ventrally flattened, slightly elongate with subparallel sides but not reaching middle of clypeus, subtriangular, with narrowly rounded apex ( Fig. 36 ); frons with short, tawny setae either side of middle in pristine specimens. Clypeus of females not or only weakly concave, densely punctate to rugopunctate, punctures large, with short setae, apex broadly parabolic, strongly reflexed into rounded lobe at center; frons with low, slightly elongated, longitudinal “horn” at center, sides subparallel, apex narrowly rounded, barely free. Interocular width equals 6.0 transverse eye diameters. Antenna with 10 antennomeres, club distinctly longer than antennomeres 2–7 in males, subequal in length to antennomeres 2–7 in females. Pronotum: Surface opaque, with small, sparse punctures near lateral margins. Lateral margins slightly emarginate between middle and basal angle, with complete marginal bead. Elytra: Surface opaque, lacking elevated, parallel costae on disc; suture slightly elevated on apical half. Surface with small, sparse punctures only near apices, apices at suture produced in males, subquadrate to slightly, produced in females. Pygidium: Males with transversely concentric, vermiform strigulae with minute, tawny setae; females similar but setae slightly longer. In lateral view, surface nearly flat to weakly convex in both sexes. Venter: Metasternum punctate on lateral thirds, punctures moderate in size and density, denser and larger on anterior and posterior margins; central third nearly impunctate. Mesometasternal process, in lateral view, moderate in length, parallel to ventral axis of body; in ventral view, sides parallel, apex broadly rounded. Abdominal ventrites 1–6 of males with punctures moderate in size and density on lateral thirds, with small, sparse punctures on central third; females with punctures larger, denser, completely covering sternite 6. Legs: Protibia of males slender, unidentate or bidentate near apex, occasionally with slight swelling behind middle suggestive of 3rd tooth, all but apical tooth usually obsolete. Females with protibia broader, strongly tridentate, basal tooth slightly removed. Parameres: In caudal view, form subrectangular, apices broadly rounded, each with minute, subapical tooth projecting upwards ( Figs. 37–38 ). Basal piece about 1.5 times as long as parameres.

Distribution. The distribution of A. soror is only partially known since there are so few specimens in collections with reliable data.

Locality Records. 31 specimens from AMNH, CASC, FMNH, LACM, MNHN, MZSP, NMPC, and ZMHU. BRAZIL (1). AMAZONAS (1): Benjamin Constant. COLOMBIA (24). META (13): Villavicencio. SANTANDER (8): Umbria, Guines Fluss (Quebrada Las Guines). NO DATA (3). PERU (6). JUNÍN (5): Chanchamayo, Satipo. NO DATA (1).

Temporal Distribution. Only three specimens among the 31 studied had any temporal data. August (3).

Diagnosis. Although similar in form and color to A. carmelita (and sympatric in part of its range), A. soror is smaller (17.4–22.7 mm versus 19.5–28.0 mm). Males are easily distinguished because the occipital tumescence in A. soror is subtriangular to narrowly rounded and does not reach the middle of the clypeus, whereas the horn in A. carmelita is elongate (extending to at least the middle of the clypeus) and with subparallel sides and a weakly to distinctly emarginate apex (compare Figs. 36 and 2 ). Females can also be distinguished by the short, barely free occipital tumescence in A. soror , while in A. carmelita this area is a low, longitudinal tumescence lacking a free apex.

Allorrhina soror is also similar to A. nigerrima . Males of A. soror have an occipital horn that is slightly more elongate and subtriangular to narrowly rounded apically; the tumescence is short and broadly arcuate in both sexes of A. nigerrima (compare Figs. 36 and 26 ). The club of the antenna is only slightly longer or subequal in length to antennomeres 2–7 in females of A. soror , while the club is distinctly longer than antennomeres 2–7 in females of A. nigerrima . The lateral margin of the pronotum is slightly emarginate between the middle and basal angle in A. soror and not emarginate in A. nigerrima . These are subtle differences and can best be seen and compared with authoritatively identified specimens. Lastly, the parameres of A. soror are, in caudal view, broadly rounded and not widely separated but broadly separated with acute apices that curve towards one another in A. nigerrima (compare Figs. 37 and 28 ).

Natural History. There is nothing known of the natural history of this beetle.

Figures

Figs. 35–38. Allorrhina soror. 35) Habitus; 36) Male, head, arrow indicates occipital horn; 37–38) Parameres.

Figs. 1–5. Allorrhina carmelita. 1) Habitus; 2) Male head; 3–4) Parameres; 5) Mesometasternal process.

Figs. 25–29. Allorrhina nigerrima. 25) Habitus; 26) Male, head, arrow indicates occipital horn; 27) Female, head, arrow indicates frontal tumescence; 28–29) Parameres.