Stenotarsus globosus Guerin-Meneville

Stenotarsus globosus Guérin-Méneville

(Figs. 1, 16–17, 56, 92, 117, 127, 134, 145, 150, 154, 160, 185, 187, 196, 204–205, 247, 259)

Stenotarsus globosus Guérin –Méneville, 1857: 270. Gorham 1890: 136; Arrow 1920: 50; Blackwelder 1945: 439; Strohecker 1953: 52; Roubik & Skelley 2001: 255; Arriaga-Varela et al. 2007: 14; Shockley et al. 2009a: 82.

Stenotarsus circumdatus Gerstaecker, 1858: 323. Gorham 1890: 136; Arrow 1920: 50; Blackwelder 1945: 439; Strohecker 1953: 51; Arriaga-Varela et al. 2007: 14; Shockley et al. 2009a: 81. New synonym.

Stenotarsus cordatus Gorham, 1890: 134. Synonymized by Arrow 1920: 50.

Stenotarsus discipennis Gorham, 1890: 136. Blackwelder 1945: 439; Strohecker 1953: 52; Arriaga-Varela et al. 2007: 14; Shockley et al. 2009a: 81. New synonym.

Stenotarsus tarsalis Gorham, 1890: 137. Strohecker 1953: 57; Arriaga-Varela et al. 2007: 16; Shockley et al. 2009a: 85; Stenotarsus circumdatus var. tarsalis Arrow, 1920: 50; Blackwelder 1945: 439. New synonym.

Diagnosis. This species is most similar to S. raramuri sp. nov., S. rubrocinctus Gerstaecker and S. shockleyi sp. nov., in sharing similar antennal structure (Figs. 56, 72, 75), genitalia of both sexes (Figs. 204–205; 247), and the following features of the male: metaventrite with a concavity between mesocoxae (Figs. 88–89), metatibia with a row of small tubercles on medial margin (Figs. 145, 160, 177–178, 181), and metafemur with a tooth on medial margin near trochanter (Figs. 150–153). Stenotarsus globosus is further distinguished from these species by the following set of characters: larger size; body uniformly dark brown except last 5–6 antennomeres (Fig. 16) or with contrasting coloration (Fig. 17) with antenna uniformly black or with antennomeres 1–7 red or gradually infuscate; pronotum black or margined by red; elytra with foveolate punctures rather small (Fig. 117); metafemur with tooth moderately large, curved and narrowly rounded at tip (Fig. 150).

Description of males. Body 6.0–7.0 mmlong, short oval, markedly convex (Figs. 16–17), 1.56–1.75X as long as wide, 2.60–2.87X as long as high. Completely dark reddish-brown, except last five or six antennomeres (Fig. 17) or with contrasting coloration (Figs. 1, 16) with head dark red, antenna uniformly black or with antennomeres 1–7 red or gradually infuscate; pronotum black (Fig. 1) or with lateral margins red sometimes leaving only a subtriangular mark on disc; hypomeron red to infuscate; prosternum red to sometimes infuscate; scutellum red or black; elytra red, each elytron with a large, oval, black macula; epipleura red; pterothorax black with mesoventrite infuscate red at least at center; legs black to orangered; first ventrite black with lateral and posterior margins orange, ventrites II–VI orange. Densely covered with long, suberect, golden setae, with darker setae in the black parts of elytra and pronotum.

Head: Clypeus transverse, 1.8–2.2X wider than long. Terminal labial palpomere narrow, acuminate, narrowly truncate apically. Interocular distance 0.63–0.68X as wide as head. Antenna moderately long, slender (Fig. 56), 0.43–0.44X as long as body; scape 1.4X as long as wide, 1.8X longer than pedicel; pedicel 1.1X longer than wide; third antennomere 1.6X as long as wide, 1.4X as long as pedicel; fourth subequal to third; fifth 2X as long as wide, 1.7X as long as pedicel; sixth 1.8X as long as wide, 1.6X as long as pedicel; seventh subequal to sixth; eighth 1.3X as long as wide, 1.5X longer than pedicel; antennal club 0.4X as long as total antennal length; ninth antennomere symmetrical, widened apically, 1.3X as long as wide at apical side, 2X as long as pedicel; tenth widened apically, 1.2X as long as wide, 2.2X as long as pedicel; terminal antennomere slightly asymmetrical, subrectangular, slightly widening apically, 1.6X as long as wide, 3.6X as long as pedicel.

Prothorax: Pronotum (Fig. 92) widest at base; markedly transverse: 2.11–2.45X wider than long; 2.25–2.45X wider than head; 1.95–2.15X wider at base than atfront angles. Sides weakly convergent in posterior half, then weakly rounded to front angles. Front angles produced, right-angled to briefly acute or narrowly rounded at tip. Hind angles slightly acute. Anterior margin narrow, slightly arcuate medially. Lateral margins moderately raised and wide, weakly narrowing posteriorly; width of margin at base 1/4 of the distance between basal pore and hind angle; area between marginal line and pronotal edge weakly concave. Disc moderately convex, finely and closely punctate. Longitudinal sulci moderately deep, lacking anteriorly, short, weakly curved medially. Basal pores large, curved, oblique. Basal sulcus only impressed close to pores. Pronotal base lobed medially. Prosternal process (Fig. 127) narrow at base, widened posteriorly; scarcely narrower than longitudinal procoxal diameter apically.

Pterothorax: Scutellum triangular (Fig. 134), moderately large, 1.65–1.80X wider than long, 0.18X as wide as pronotum. Elytra 4.1–5.0 mm long, 1.02–1.30X longer than wide, 3.40–3.62X longer and 1.40–1.52X wider than pronotum; ovoid, widest near basal third, then roundly converging to acuminate apex, densely punctate (Fig. 117) with foveolate punctures rather small and shallow, separated by 1.5–6.0 diameters, sparser and shallower apically. Humerus moderately prominent. Epipleuron at base 0.8X as wide as intercoxal process of metaventrite. Mesoventrite deeply excavated in front, bearing small setose pores laterally; mesoventral process as wide as longitudinal coxal diameter, without medial carinae. Metaventrite weakly convex, with transverse, more densely pubescent concavity on intercoxal process between mesocoxae; with pair of small setose pores of approximately same diameter posterior to each mesocoxa. Metepisternum with small setose pore.

Legs: long and slender (Figs. 145, 160). Trochanters simple. Meso- and metafemora rather slender, widest barely before midlength; mesofemur unarmed; metafemur slightly longer than mesofemur, bearing moderately long decumbent setae, with a well developed, moderately large and rounded tooth in the base of medial margin (Fig. 150). Meso- and metatibiae very slender; metatibia as long as metafemur, 0.34–0.41X as long as elytra, very weakly and gradually widened apically, slightly bent in apical third, with a row of small tubercles on medial margin. Metatarsus (Fig. 154) 0.42–0.54X as long as metatibia; second tarsomere produced and lobed, 2X wider apically than fourth tarsomere at midlength.

Abdomen: Ventrite I almost as long as metaventrite and slightly shorter than ventrites II–V combined, with sparse foveolate punctation posterior to metacoxae, without protuberances. Ventrite V scarcely longer than IV, with apex truncate; ventrite VI rounded apically. Tergite VIII truncate. Median lobe slender, curved, continuously narrowed with apical crest, in ventral view (Fig. 205), widened apically, in lateral view (Fig. 204). Tegmen with moderately large submembranous tegminal plate (Fig. 196).

Description of females. Body 6.1–7.4 mm long, 1.57–1.75X as long as wide, 2.50–2.80X as long as high. Antenna 0.35–0.38X as long as body. Pronotum 2.07–2.20X wider than long, 1.90–2.15X wider at base than at front angles, 2.2–2.4X as wide as head. Elytra 4.15–5.20 mm long, 1.07–1.30X longer than wide, 3.5–4.0X longer and 1.5–1.7X wider than pronotum. Metaventrite moderately convex, without concavity or other modification on the anterior margin. Metafemur unarmed. Metatibia 0.30–0.33X as long as elytra, linear, unarmed, as long as metafemur (Fig. 185). Metatarsus 0.5–0.6X as long as metatibia. Ovipositor with proctiger rounded, coxites wide, without styli (Fig. 247).

Sexual dimorphism. Males have a concavity on metaventrite, metatibia with a row of small tubercles and metafemur with a tooth on base. Females have proportionally larger elytra and shorter antennae and legs.

Variation. This species is highly variable in proportions and coloration. There are two main color morphs: the uniformly dark brown form (Fig. 17), distributed in the Sierra Madre del Sur of Oaxaca, México; and a contrastly colored form (Figs. 1, 16), distributed from central eastern México to Guatemala. The darker contrastly colored specimens have antennae, pronotum and legs completely black (Fig. 1).

Material examined. Types. Lectotype of Stenotarsus globosus Guérin-Méneville (present designation) (female): Syntype [round, blue bordered label] / Type H. T. [round, red bordered label] / Gorham 91–50 [H] / Stenotarsus globosus Guérin (Var.) Mexique (NHM). Lectotype of Stenotarsus circumdatus Gerstaecker (present designation) (male): Xalappa, Deppe / Hist. Coll. (Coleoptera), Nr 21857, Stenotarsus circumdatus Gerst., Xalappa, Deppe, Zool. Mus. Berlin [green label] / SYNTYPUS Stenotarsus circumdatus Gerstaecker, 1858. Labelled by MNB 2006 (MNB). Paralectotype of Stenotarsus circumdatus Gerstaecker (female): same data as lectotype (MNB). Lectotype of Stenotarsus discipennis Gorham (present designation) (male): Syntype [round, blue bordered label] / Type H. T. [round, red bordered label] / Capetillo, Guatemala, G.C. Champion / Sp. figured / S. discipennis / B.C.A., VII, Stenotarsus [p] discipennis Gorh. [h] (NHM). Paralectotype of Stenotarsus discipennis Gorham (female): Syntype [round, blue bordered label] / Cerro Zunil, 4000 ft. Champion / B.C.A., VII, Stenotarsus [p] discipennis Gorh. [h] (NHM). Lectotype of Stenotarsus tarsalis Gorham (present designation) (male): CORDOVA / Mexico, Salle col. / Type / S. tarsalis / Stenotarsus circumdatus Gerst. = Stenotarsus globosus Guer. Apud Salle [h] / B.C.A., VII, Stenotarsus [p] tarsalis Gorh. [h] / Syntype [round, blue bordered label] / Stenotarsus tarsalis Gorham [h] det. R.G. Booth 2010 (NHM).

Other material. Guatem. 8.–9.11, El Tumbador, Riedel S.G. / Stenotarsus circumdatus Gerst.?, det. H.F. Strohecker (1 female: MNB); GUATEMAL. Tumbador, v.12, C. Riedel S. / Stenotarsus discipennis Gorham, det. 1977, H.F. Strohecker (1 female: MNB); Tactic, Vera Paz, Champion (1 male, 1 female: NMNH); [same data plus] Stenotarsus globosus Guer (1 female: NMNH); [same data plus] / Stenotarsus globosus Guérin dt. Stroh. (1 male: NMNH); Tactic, Vera Paz, Champion / 91972 / Stenotarsus globosus Guer (1 male: MNB); [same data except] 91971 / Stenotarsus globosus Guérin det. H.F. Strohecker (1 female: MNB); Chiapas Mex, L. Hotzen ’19, Pacific Slope Cordilleras, 800–1000 (2 males, 1 female: NMNH); México: Oaxaca, Km. 1 carr. Juquila-San Pedro Ocotepec, 19-VIII-2003, Alt. 1600 m, Hongos, Q. Santiago y L. Delgado, Stenotarsus globosus Guérin-Méneville E. Arriaga-Varela det. 2006 (1 female: IEXA); Km 21 carretera Yolotepec - Juquila, BE, 1850m, ex Lactarius IIIB, 30–31.VII.1991, J. L. Navarrete, G.A. Quiroz y L. Delgado #871 (2 males, 2 females: CZUG); Juquila, Santa María Yolotepec, 1–2.VIII.1990, ex Hojarasca, J. L. Navarrete, G.A. Quiroz-Rocha y L. Delgado cols. (1 male: CZUG); México, Oaxaca, Km. 26 Teotitlán-Huatla, 2400 msnm, 16-III-1989, A. Cadena L. Cervantes (1 female: CNIN); México: Veracruz, Cerro Acatlán, Mesófilo, 17-VIII-1990, Col. J. L. Navarrete y L. Delgado / ex Russula IIIA #488/ Stenotarsus circumdatus Gerstaecker, E. Arriaga-Varela det. 2006 (1 female: CZUG) México, Veracruz: Córdoba, Miguel Aguilar, Alt. 940 m, 29–31.III.1996, E. Santos y L. Delgado / Stenotarsus militaris Gerstaecker, F.W. Shockley det. 2002/ Stenotarsus discipennis Gorham E. Arriaga-Varela det. 2006 (1 female: IEXA); Cordova 6 / Coll. J. Flohr / circumdatus Gsr. / Stenotarsus globosus Guér. ex description, det. H.F. Strohecker (1 male: MNB); 277 / Stenotarsus circumdatus Gerst. Mexique (1 male: MNHN); Mexico, Coll. J. Flohr (1 female: MNB); Veracruz, Presidio, 8-VII-1993, C. Mayorga. (1 male: CNIN).

Distribution. GUATEMALA: Alta Verapaz, Quetzaltenango; MEXICO: Chiapas, Oaxaca, Veracruz (Fig. 259).

Biological Notes. Altitudinal range: 350–2400 m. Habitat: cloud forest. Host fungi: Russula sp. (Russulales: Russulaceae). Period of activity: March to August.

Remarks. The color variation of this species led to the establishment of different species in the past: Stenotarsus circumdatus Gerstaecker, S. discipennis Gorham and S. tarsalis Gorham. However, no significant morphological differences were found to validate the separation of these species, and therefore they are synonymized here under Stenotarsus globosus Guérin-Méneville.

Stenotarsus tarsalis (Gorham 1890) was described originally based on three specimens: a male from Cordova and two putative females from Xalapa. None were designated as holotype. Gorham noticed the tooth on the metafemur of the male from Cordova and suggested possible affinity with S. rubrocinctus Gestaecker. From the study of the series of syntypes of S. tarsalis, we found that one specimen from Xalapa was actually a male, and moreover both specimens from this locality were not conspecific with the male from Cordova, but instead belong to S. thoracicus, another species described by Gorham (1890) in the same work. The male from Cordova is here chosen as the lectotype to stabilize the identity of S. tarsalis.

Blackwelder (1945) cited S. globosus from Honduras, Panamá, Colombia, Guyana, Perú and Bolivia. These records are most likely due to misidentifications as no specimens from south of Guatemala were found in this study. Those localities therefore remain dubious collecting records.