Ardearsus Opitz, 2016

Opitz, Weston, 2016, Classification, Natural History, and Evolution of Tarsosteninae (Coleoptera: Cleroidea: Cleridae). Part III. Taxonomy of the New World GeneraArdearsusOpitz, New Genus, AbiliellaPeracchi, OchraceaOpitz, New Genus, andSomaovalisOpitz, New Genus, The Coleopterists Bulletin 70 (1), pp. 153-167 : 153-167

Ardearsus Opitz , new genus

Type Species. Ardearsus morulus Opitz , new species. By present designation.

Diagnosis. The members of this monotypic genus resemble those of Abiliella , but in Ardearsus specimens the antenna is comprised of 10 antennomeres, the terminal palpomeres of the maxilla and labium are subsecuriform ( Fig. 16 ), the tarsal unguis has a distinct denticle, the tibial spur formula is 1-2-2, the elytral disc is devoid of asetiferous punctures, and the spicular apodemes are fused at their posterior extremity. In Abiliella specimens, the antenna is comprised of 11 antennomeres, the terminal palpomeres of the maxilla and labium are securiform ( Fig. 15 ), the tarsal unguis lacks a denticle, the tibial formula is 0-1-1, the elytral disc shows 8 striae of asetiferous punctures, and the spicular apodemes are fused at their anterior extremity.

Apotypic Characteristics. T h e p h a l l o b a s i c struts and apodeme unite to form a very broad plate; the spicular apodemes are fused at their anterior extremity; phallobasic rod absent.

Description. Size: Length 5.0–7.0 mm; width 1.7–2.0 mm. Form: Oblong rectangular, about 3 times longer than broad. Vestiture: Disc of cranium and pronotum vested with pale setae, elytral disc vested profusely with 2° setae. Head: Cranium quadrate, frons not very wide, indented with small setiferous punctures, latter widely separated; gula large, trapezoidal, sutures diagonal, gular process short; labrum short, medial incision deep, curvate concave; mandible stout, dens welldeveloped; maxillary terminal palpomere subsecuriform ( Fig. 16 ); ligula deeply incised, ligular lobes not flared, labial terminal palpomere subsecuriform; eyes large, coarsely faceted, ocular notch large; antenna ( Fig. 5 ) comprised of 10 antennomeres, capitate, capitulum lax, scape short, about as long as combined length of pedicel and antennomere 3, funicular antennomeres subfiliform, capitular antennomeres not compacted, antennomeres 8 and 9 subtriangular, antennomere 10 subovoid. Thorax: Pronotum slightly transverse ( Fig. 10 ), convex, lateral margins with tubercle, sculptured with shallow, setiferous punctures, prebasal fissure not deep, prointercoxal process not expanded distally; pronotal projections short; elytra sculptured with minute, setiferous punctures, asetiferous punctures absent, epipleural fold in oblique position, broad in anterior region, narrowed to elytral apex, anterior margin not carinate; tibial spur formula 1-2-2, tarsal pulvillar formula 3-3-3, unguis with well-developed denticle. Aedeagus: Shorter than length of abdomen ( Fig. 36 ); phallobase minutely lobate anteriorly; lobes not fimbriate; phallobasic struts and apodeme unite to form a very broad plate; phallobasic rod absent; phallic apex digitiform; phallic plates broad; phallobasic rod present; spicular plates not flared; spicular apodemes fused at their anterior extremity; intraspicular plate oblong-linear.

Distribution. This genus is known only from Santa Cruz, Bolivia.

Etymology. The generic epithet Ardearsus is a Latin derivative that stems from radio (= glow). I refer to the relucent character of the elytral disc.

Ardearsus morulus Opitz , new species ( Figs. 5, 10, 16 , 29 , 36 , 39 )

Holotype. ♂. BOLIVIA: Santa Cruz, Porterville’ s del Glenda, 40 km NW Santa Cruz de la Sierra, X/ 1-10/08, Morris & Wappes. ( MNKM).

Paratype. One specimen. BOLIVIA: Santa Cruz: Porterville’ s del Glenda , 40 km NW Santa Cruz de la Sierra, 1-10-X-2008, Morris & Wappes. ( FSCA) .

Diagnosis. This species is distinguished from other members of other genera treated in this work by the testaceous forebody.

Description. Size: Length 7.0 mm; width 2.0 mm. Form: As in Fig. 29 . Color: Cranium and pronotum red-yellow; pterothorax and abdomen black; legs bicolorous, femora mostly testaceous, infuscated distally, tibiae and tarsus brunneous; elytral disc black, epipleuron yellow. Head: Cranium finely punctate, frons narrower than maximum width of eye (FW/EW = 21/26); funicular antennomeres subfiliform, antennomeres 8 and 9 triagonal, antennomere 10 ovoid ( Fig. 5 ). Thorax: Pronotum slightly transverse ( Fig. 10 ) (PL/PW = 68/70), finely punctate, with tubercle at sides; elytral disc sculptured with small, setiferous punctures (EL/EW = 250/70); disc shallowly corrugated. Abdomen: Male pygidium incised at middle of anterior margin. Aedeagus: Phallobase membranous ventrally; lobes small; phallobasic rod absent; phallobasic struts and apodeme unite to form a very broad plate; phallic apex digitiform; phallic plates wide.

Variation. Length 5.0–7.0 mm; width 1.7– 2.0 mm. Otherwise, the two specimens examined are quite homogeneous.

Natural History. The type specimens were collected in October.

Distribution. This species is known only from Santa Cruz, Bolivia ( Figs. 39 ).

Etymology. The specific epithet morulus is a Latin adjective that means “black”. I refer to the predominantly black color of this beetle.

Figures

Figs. 1–17. Morphological structures. Antenna: 1) Abiliella albosutura; 2) Abiliella fasciata; 3) Abiliella galbina; 4) Ochracea xanthosa; 5) Ardearsus morulus; 6) Somaovalis sinestigma; 7) Somaovalis sexnaeva. Pronotum: 8) A. albosutura; 9) Abiliella fasciata; 10) A. morulus; 11) O. xanthosa; 12) Somaovalis sexnaeva; 13) Somaovalis sinestigma; 14) A. galbina. Apical maxillary palpomere: 15) A. fasciata; 16) A. morulus; 17) O. xanthosa.

Figs. 33–38. Abdominal terminalia and aedeagi. 33) Abiliella albosutura; 34) Abiliella fasciata; 35) Abiliella galbina; 36) Ardearsus morulus; 37) Ochracea xanthosa; 38) Somaovalis sexnaeva.

Figs. 26–29. Habitus. 26) Abiliella albosutura; 27) Abiliella fasciata; 28) Abiliella galbina; 29) Ardearsus morulus.

Fig. 39. Geographical distributions of seven tarsostenine species.