Pachystethus nectoctenus Ramírez-Ponce & Morón, 2012

Ramírez-Ponce, Andrés & Morón, Miguel Angel, 2012, Revision of the genus Pachystethus Blanchard with description of three new species from Mexico (Coleoptera: Scarabaeidae: Rutelinae: Anomalini), Zootaxa 3394, pp. 1-24 : 13-15

Pachystethus nectoctenus Ramírez-Ponce & Morón , new species

( Figs. 20–25 , 43 a–b, 49a–b)

Type material (31 males, 36 females; CNIN, IEXA, MXAL, NHM, ZMHB). Holotype (male, IEXA), labeled: a) “ MEXICO, Puebla, Xicotepec de Juárez, 2-IX-73, planta silvestre, R. Boue” (handwritten); b) our red holotype label. Allotype (female, IEXA), labeled: as holotype; b) our yellow allotype label. Paratypes (30 males, 35 females), with our paratype yellow labels and following label data: “ México, Hidalgo, Cañada de Otongo, 5-X- 80, 760 m, s/ Calliandra sp. 5 pm. M. A. Morón y R. Terrón” (typeface) (1 male, 1 female, MXAL); same data as holotype and allotype (2 males, 3 females MXAL; 3 males, 6 females, IEXA); a) “ Mexico, Puebla, Patla, 19-VIII-94, E. Barrera, H. Brailovsky” (typeface); b) Callistethus vidua (Newman) M. A. Morón , det. 97 (typeface) (1 female, CNIN); same data except “ 6-VIII-95, H. Brailovsky” (typeface) (1 female, CNIN); “Villa Juárez, 27-IX ” (typeface) (1 male, IEXA); “Barranca de Patla Puebla 28/II/76 Figueroa” (handwritten) (1 female, CNIN); “ México: Puebla: Pahuatlan, 17-VIII-94, Brailovsky, E. Barrera” (typeface), (3 females, CNIN); a) “ México, Puebla, Yahonahuac, Presa La Soledad, 20-04- 97, 700 m, sobre veg. diurno, D. Bermudez, col.” (typeface), b) “ Callistethus vidua (Newman) M. A. Morón , det. 97” (typeface) (1 female, CNIN); a) “Mi Ranchito, Villa-Juárez, Puebla, México 4-VI-66 ” (handwritten), b) “ Callistethus vidua (Newman) M. A. Morón , det. 97” (typeface) (1 female, CNIN); a) “ Mexico, Puebla, Cuetzalan, 940 msnm, 27-30-IV-94, G. Ortega, E. Barrera” (typeface), b) “ Callistethus vidua Ƥ (Newman)” (handwritten) “M. A. Morón, det. 97” (typeface) (1 female, CNIN); “Necaxa, Pue. 31-VIII-52, C. Bolivar” (handwritten) (3 males, 2 females, CNIN); “ Mexico Puebla” (typeface and handwritten) (1 male, ZMHB). “San Luis Potosí, Vega Larga, 6 km antes Tamazunchale, 1/V/76, Col. E. Barrera” (handwritten) (1 female, CNIN). “ Mexico: Veracruz, Puente Tomata, 23-Oct-1993, S. Zaragoza, A. Mendoza” (2 males, 2 females, CNIN) (typeface); “ Mexico, Veracruz, Xalapa 4-VIII-1992 Bosque Mesófilo-Cafetal 1400m Flores. R. Guadalupe F. Capistran” (1 male, 1 female, MXAL); “ Mexico, Veracruz, Xalapa, Rancho Guadalupe. Bosque Mesófilo-Cafetal 1,360m. Luz. 30-V-91. M.A. Morón” (1 female, MXAL); “ México: Veracruz, Xico, 12-VIII-2000, E. Micó leg.” (typeface) (1 male, IEXA); “ México, Veracruz, Coatepec, Briones. 30-II-2001 Suelo M.A. Morón col.” (1 female, IEXA); “Xalapa, Rancho Guadalupe, Bosque mesófilo-cafetal, 1360 m, 30-X-92, M. A. Morón” (typeface) (1 female, MXAL); “Xico, 12-VII-2000, E. Micó” (typeface) (2 males, 1 female, MXAL); “Coatepec” (typeface) (1 female, CNIN); “Coatepec, Höge ex BCA” (typeface) (1 female, MXAL); “Coatepec, Briones, 30-II-2001, Suelo, M. A. Morón” (typeface)(1 female, NHM); same data except “ 14-VII-90 ” (typeface) (1 male, IEXA); “ 17-VII-97, 1450m, flor Hibiscus , 1 pm” (1 female, MXAL); “ 2-VIII-97 ” (1 male, MXAL); “ 12-IX-94, 1360 m, cópula sobre Persea ” (typeface) (1 male, 1 female, MXAL; 1 male, IEXA); “ 17-X-99, flor Hibiscus ” (1 male, NHM; 1 male, MXAL); “ 13-VIII-95 ” (1 female, IEXA); “Fortín, Ver. 3-IV-1944. C. Bolívar” (typeface) (1 female, CNIN); Tajín, Veracruz Alt. 20 mts, 27-VI-76, Figueroa” (handwritten) (1 male, CNIN); a)“F. Islas” (typeface) b) “Mataredonda, Ver. 12-XI-1941.” (handwritten) (1 male, CNIN); a) “Orizaba, Mexico ” (typeface), b) (male symbol, typeface), c) “ Spilota vidua Newman ” (typeface) (1 male, ZMHB); a) “Coatepec, Mexico. Hoege” (typeface), b) “88614” (typeface) (2 males, ZMHB); “ Mexico Jalapa” (typeface and handwritten) (3 males, ZMHB).

Description. Holotype: male. Length 9.1 mm, width 4.6 mm. Color reddish yellow on clypeus, anterior half of frons, scape, pedicel, funicle, lateral margins of pronotum, abdomen, pygidium, femora, and most of tibiae; shiny black on antennal club, posterior half of frons, disc of pronotum, elytra, tarsomeres, and apex of mesotibia and metatibia. Head. Clypeus subtrapezoidal, clearly wider than long; anterior border straight, slightly upturned and directed forward, anterior angles rounded; clypeal surface with uniform, dense, large punctures. Frontoclypeal suture well defined, straight. Frons weakly convex, densely rugopunctate at center with scattered, small punctures along lateral and posterior margins. Punctures around eyes are more disperse and smaller than on frons, and are combined with some long setae. Antennal club clearly longer than length of all preceding antennomeres combined; lamellar shape semirectangular, not curved at apex ( Fig. 21 ). Eyes small, ovate; ocular margin noticeable and exposed dorsally. Eye canthus thick with glabrous, rounded apex; flattened surface with shallow, small punctures. Maxillary basistipe flat, irregularly punctate, scarcely setose. Labrum wide, sinuate. Labium sinuate, as long as wide, with irregularly rugopunctate setose prementum. Pronotum wider than long, weakly convex; with small number of medium size, shallow, circular punctures and noticeable lateral pits; posterior angles flattened and lateral borders slightly angled. Mesepimera slightly exposed over humeral calli. Space between mesocoxae wide; mesometasternal process long, projecting anteriorly past mesocoxa but do not reach procoxae, with wide rounded apex directed downward; metasternum densely punctate, sides uniformly setiferous, mesial region glabrous and longitudinally sulcate. Elytra flattened, short, ovate; striae weakly impressed with shallow, small punctures; elytral costae discrete, suture slightly raised towards posterior half; preapical slope brief; lateral margins nearly straight (without wide bend at the end of epipleural fold) with sparse, short setae. Epipleural fold sharp in lateral view, gradually narrowed after metacoxa. Scutellum : slightly wider than long; lateral margins angled, apex acute; surface uniformly and shallowly punctate. Abdomen: sternites scarcely setiferous, each one with one discontinuous row of setiferous punctures near posterior border and wide glabrous central area, weakly punctate. Legs: protarsomeres 1–4 short, wider than protarsomere 5. Protibia stout, gradually wider towards the apex; lateral borders divergent; external border with proximal denticle short and wide; distal denticle large, oblique ( Fig. 20 ). Mesofemora with a well-defined longitudinal keel, with long setae. Metafemora without longitudinal keel. Metatibia with scarce setiferous, large punctures. Metatarsomeres 1–2 large, longer than metatarsomeres 3–4. Genitalia ( Figs. 22–23 ): parameres shorter than length of tectum, with complex form; upper part irregular with dorsal protuberance and median area widened; apex much narrowed with upturned point; lower part of parameres nearly straight, obliquely directed downwards, basally widened, apically narrowed. Basal half of tectum clearly wider than distal half, with outstanding posterolateral calli. Basal piece with short, round apodema. Spiculum gastrale ( Fig. 24 ) stout, basal part straight, uniformly wide, slightly short than lateral sclerites; associated plates subtriangular with widely rounded apex and long setae near exterior border.

Allotype: female. Length 11.3 mm, width 5.9 mm. Color shiny reddish yellow or dark red on nearly entire body; shiny black on antennal club, elytral borders, anterior part of mesosternum, apexes of mesotibiae and metatibiae, and tarsi. Body stouter than in male, epipleural fold swollen, protibiae and protarsi not swollen, metatarsomeres wider than in male. Antennal club as long as the length of the pedicel and funicle combined. Genital plates small, short, semitriangular; with irregular inner border with sparse, long setae ( Fig. 25 ).

Paratypes (n = 57). Length: 8.3–12.0 mm, width: 4.3–6.2 mm. All the male specimens examined have the pronotum with reddish-yellow lateral margins and black disc and females have yellow-red coloration covering the body. Although none were examined, it is possible that some individuals are completely black.

Diagnosis. Clypeus subrectangular. Pronotum with small (approximate diameter 0.027 mm), circular punctures. Elytral striae shallow, indicated by punctures; posterior calli and distal part of interstriae not prominent; lateral margins without bend. Protarsomeres 1–4 wider and shorter than protarsomere 5. Protibia notably wider towards the apex, with divergent lateral borders. Parameres short and complex, with transverse keels on dorsal surface (Table 1).

Etymology. From the ancient indigenous Nahuatl language nectoctene, meaning false, double faced, deceptive ( Siméon 1988), as reference to the previous confusion with true P.viduus .

Remarks. Is possible that in previous works wherein the specimens were recorded as bicolored or completely black, specimens of both species and/or P.viduus were included. The external morphology of these species are similar, however, a detailed examination shows their differences in terms of dorsal sculpture, shape of prolegs, and the form of parameres (Table 1).

Distribution, phenology, and natural history. This species is distributed along the humid slopes of Sierra Madre Oriental in Mexico, between 20–1400 m in elevation, from the state of San Luis Potosi (near Tamazunchale) to center of the state of Veracruz (Fortín de las Flores) ( Fig. 54 ). Adults are active from February to November, but are more abundant from August to October. Host records for adults include the inflorescences of “mafafa” Xanthosoma robustum (Araceae) , flowers of “tulipán” Hibiscus rosasinensis (Malvaceae) , and Calliandra sp. ( Fabaceae ), as well as leaves of “aguacatero” Persea americana (Lauraceae) ( Burmeister 1844; Morón 1994, 1996, 1997).

Third stage larva was described by Micó et al. (2003) as Callistethus vidua , with specimens reared from eggs laid in captivity by females collected near Xico, Veracruz.

Figures

FIGURE 54. Distribution of species of Pachystethus.

FIGURES 20 – 25. Diagnostic structures in P. nectoctenus: 20) right proleg, 21) right antenna, 22) male genitalia in dorsal view, 23) male genitalia in lateral view, 24) spiculum gastrale, 25) female genital plates. Scale lines 1 mm.

FIGURES 42 – 47. Dorsal view of Pachystethus species: 42 a, b) P. viduus males; 42 c) P. viduus female; 42 d) P. viduus female, lectotype; 43 a) P. nectoctenus male; 43 b) P. nectoctenus female; 44 a) P. crassesculptus male; 44 b) P. crassesculptus female; 45 a, b) P. nutans males; 45 c) P. nu t an s female; 46 a, b) P. matzapatlecus males; 46 c) P. matzapatlecus female; 47 a) P. ixtacomitanus male; 47 b) P. ixtacomitanus female. Scale lines 1 mm.