Oectropsis chilensis, Nascimento & Monné & Santos-Silva, 2020

Nascimento, Francisco Eriberto De L., Monné, Miguel A. & Santos-Silva, Antonio, 2020, On the enigmatic genus Oectropsis Blanchard (Coleoptera, Cerambycidae Lamiinae): tribal allocation, synonymy, and new species, Zootaxa 4845 (2), pp. 211-224 : 216-218

Oectropsis chilensis sp. nov.

( Figs. 5–13 )

Exocentrus pusillus ; Barriga et al., 1993: 71 (hosts).

Oectropsis pusillus ; Barriga & Cepeda, 2005: 468; Monné, 2001: 27 (cat. hosts).

Barriga & Cepeda (2005) redescribed O. pusillus (= O. chilensis sp. nov.) as follows (translated): “ Diagnosis: General color dark brown, pilosity whitish dorsally and ventrally, without elevated protuberances on pronotum, and with weak protuberances on elytra, pronotal punctation coarse and well-marked, with white setose macula on dorsal surface of elytra. Length: 2.5 to 3.5 mm; humeral width: 1.0 to 1.5 mm. Head: densely pubescent, setae long and interspersed of copperish white, punctation between antennal tubercles rounded and deep, slightly dense, longitudinal sulcus long and deep, labrum small, rounded and finely punctate. Antennae dark brown, entirely covered with fine whitish pubescence, light maculae of pubescence slightly distinct [pubescence contrasting with remaining pubescence], antennomeres III–XI with dark macula on apex. Prothorax: Slightly longer than wide, convex, covered with whitish pubescence, especially on disc and lateral spines, coarsely punctate, punctures dense, rounded and deep, in margins presents spinal process not so acute, on disc is slightly convex, without elevated protuberances ( Fig. 10 ), prosternal process subtriangular and carinate, coxal cavities slightly angular, coxae globose. Elytra: Convex, densely setose, setae yellowish white, forming macula with white setae in sides under humeral zone, setae erect and dark arranged in rows, punctation coarse and well-marked, rounded and deep, with two elytral weakly raised protuberances. Scutellum wide, rounded and setose. Abdomen: Metaventrite and sternites setose ventrally [redundancy], covered with whitish pilosity. Legs: Metatibiae lacking macula with light pilosity, with a set of semierect dark and whitish setae. Intraspecific variations: Some specimens studied have smaller pilosity, elytral protuberances variable, sometimes covered with dark pilosity. Geographical distribution: CHILE, 7 th Region of Maule (Province of Curicó, Talca, Linares); 8 th Bío-Bio Region (Ñuble Province); 9 th Region of Araucanía (Malleco Province); 10 th Los Lagos Region (Province of Valdivia); ARGENTINA: Neuquén, quoted by Bosq (1953); Chubut Province: Los Alerces. This species is distributed in Chile between the 7th and the 10th Regions, being also in Argentina in the provinces of Neuquén and Chubut. Hosts: cited by Barriga et al. (1993), Nothofagus dombeyi , N. pumilio and N. obliqua . New antecedent, specimens obtained from creation, on branches of Raulí, Nothofagus alpina . Time of activity of the adults: based on the reviewed material and observations in the field, this species is present throughout the year. Male genitalia: tegmen broadly divided into parameres with rounded and ciliated apex; aedeagus with anterior portion acute; internal sac with spiniform processes dense and numerous. Female genitalia: ovipositor subrectangular, membranous, long, stylus cylindrical and chitinous; 8 th tergite broad with rounded margin and covered with abundant pilosity. Material examined: [the authors listed 72 specimens from Chile and Argentina deposited at JEBC [Juan Enrique Barriga Tuñón private collection], 15 specimens from Chile deposited at MEUC [“Colección del Museo Entomológico Luis Peña, del Departamento de Sanidad Vegetal, de la Facultad de Ciencias Agronómicas, de la Universidad de Chile ”], 31 specimens from Chile deposited at Sergio Roitman private collection, and 29 specimens from Chile deposited at MNNC [“Colección del Museo Nacional de Historia Natural, Santiago, Chile ”—none of these specimens are considered here as a paratype, because it would be necessary to examine all of them to confirm the identification.

We believe that this description, accompanied by the photographs included here, accurately describes the species. Even so, we are adding the following details about the specimens of the current type series:

Head. Genae about as long as length of lower eye lobe. Distance between upper eye lobes about 3.0 width of one upper lobe. Antennae 2.0 times elytral length in male, 1.6 times in female; antennal formula (ratio) based on length of antennomere III (holotype female): scape = 1.10; pedicel = 0.30; IV = 1.40; V = 0.95; VI = 0.75; VII = 0.75; VIII = 0.65; IX = 0.60; X = 0.55; XI = 0.55. Prothorax. Sides coarsely, abundantly punctate. Pronotum with elongate, somewhat narrow smooth central area about middle; with dense Y-shaped yellowish-white pubescent band from base to sides of smooth area (whiter on some areas); with whitish, wide, not dense whitish pubescent band from smooth area to anterior margin; narrowest area of prosternal process ( Fig. 9 ) about 0.25 times width of procoxal cavity (including angular side of the cavity). Elytra. Centrobasal region with slight gibbosity (not forming distinct crest); posterior half with dense, small tuft of dark erect setae, placed dorsally just after middle (not placed on gibbosity in the holotype and paratype, but slightly elevated according to Barriga & Cepeda 2005). Legs. Profemora fusiform; meso- and metafemora clavate; tibiae with long, erect, sparse white setae; metatarsomere I shorter than II–III combined. Abdomen. With long, most decumbent whitish setae not obscuring integument, except apex of ventrite I, and apical sides of II–IV with dense fringe of yellow setae (more yellowish from III).

Dimensions in mm (holotype female/ paratype male/ paratype female). Total length, 3.7/3.6/3.0; prothoracic length, 0.9/0.9/0.8; anterior prothoracic width, 0.8/0.8/0.6; posterior prothoracic width, 0.8/0.8/0.6; maximum prothoracic width, 1.1/1.0/0.9; humeral width, 1.3/1.2/1.0; elytral length, 2.5/2.5/2.0.

Type material. Holotype female from CHILE, Maule (Región VII): Alto Vilches ( Talca province ), 1,100 m, H.F. Howden col. ( MZSP). Paratypes— 1 female, same data as holotype except 10–12.XII.1976 ( MZSP). Chile Region VIII, Cordillera de Chillan , 80km, ese Chillan, 3 male, 10 December 1993, E, Arias, collector ( LGBC). Chile Region VII, Vilches, 55km ese Talca, 1 female, 10 December 1993, E, Arias, collector ( LGBC).

Etymology. The specific epithet refers to the country ( Chile), where the holotype was collected.

Remarks. Oectropsis chilensis sp. nov. differs from O. latifrons ( Figs. 1–4 , 18 ) by the pronotal and elytral protuberances much less elevated (distinctly more elevated in O. latifrons ), and the pronotal pubescence sparser, forming longitudinal Y-shaped band on center of posterior half ( Fig. 10 ) (denser and not forming longitudinal band in O. latifrons ).

Figures

FIGURES 5–10. Oectropsis chilensis sp. nov., holotype female: 5) Dorsal habitus; 6) Ventral habitus; 7) Lateral habitus; 8) Head, frontal view; 9) Procoxa and procoxal cavity. 10) Pronotum.

FIGURES 11–18. 11) Oectropsis chilensis sp. nov., dorsal habitus. 12–13) Oectropsis pusillus, from Barriga & Cepeda (2005) (= Oectropsis chilensis sp. nov.): 12) Dorsal habitus; 11) Lateral habitus. 14) Exocentrus pusillus, “holotype”, dorsal habitus (taken from Tavakilian & Chevillote, 2020). 15–16) Oectropsis franciscae, paratype male, from Barriga & Cepeda (2005): 15) Dorsal habitus; 16) Lateral habitus. 17) E. pusillus, drawing by Blanchard (1851). 18) Oectropsis latifrons, “Lectotype”, dorsal habitus.

FIGURES 1–4. Oectropsis latifrons, male from Chile: 1) Dorsal habitus; 2) Ventral habitus; 3) Lateral habitus; 4) Head, frontal view.