Astylus alboscutellatus Pic, 1919a

Estrada, Patricia, 2021, Updating the knowledge of species of the genus Astylus Laporte (Coleoptera Melyridae) from South America, Zootaxa 4941 (1), pp. 127-141 : 128-132

publication ID	https://doi.org/ 10.11646/zootaxa.4941.1.8
publication LSID	lsid:zoobank.org:pub:AAD29455-5B1C-41DF-9E0C-6ABE7FF269AE
persistent identifier	https://treatment.plazi.org/id/03976845-FFFC-A13D-1A96-F96DFADC8EAA
treatment provided by	Plazi
scientific name	Astylus alboscutellatus Pic, 1919a
status

Treatment

( Figures 1–4)

Astylus alboscutellatus Pic, 1919a: 4 ; Pic 1929:12; Blackwelder 1945:377; Estrada 2008:601. (Type locality: Catamarca).

Types examined: alboscutellatus : one female herein designated as lectotype and labelled as follows: alboscutellatus Pic. ; n. sp. écusson gris; Rep. Argentina, Prov. Catamarca, C. Bruch; Type. ( MNHN) .

Diagnosis. Head, pronotum and elytra black, but bright with abundant coarse punctuation ( Fig.1); pronotum

widest in the middle; scutellum with conspicuous light grey pilosity. Females: antenna slightly serrated ( Fig. 2a View FIGURE 2 ); ventrite 5 with distal margin that is moderately arcuate; ventrite 6 and last tergite not fused; ventrite 6 slightly emarginated at the distal margin; last tergite elongated and moderately rounded at the distal margin ( Fig. 2b View FIGURE 2 ); membranous ovipositor with fine baculi and a sub-rectangular sclerite in the middle of the dorsal lamina ( Fig. 2c,d View FIGURE 2 ). Males: antennae moderately serrated ( Fig. 3a View FIGURE 3 ); Ventrite 1 with a short and curved process at the center, close to the basal margin; ventrite 5 strongly emarginated at the distal margin; ventrite 6 and last tergite fused like a subconical structure; ventrite 6 emarginated at the distal margin with two lateral pointed projections ( Fig. 3b View FIGURE 3 ); last tergite projected at apex ( Fig. 3b View FIGURE 3 ); sclerotized parameres, sides subparallel, apex truncate, slightly emarginated in the middle ( Fig. 4a,b View FIGURE 4 ); tegminal arms moderately thick, tegminal plate broad with a dorsal elevated fold at the midline, strongly emarginated at the distal margin ( Fig. 4c View FIGURE 4 ); Median lobe subcylindrical, elongated, sclerotized, strongly curved at base; slightly widened pre-apically; pointed apex; wide, subapical phallotreme ( Fig. 4 View FIGURE 4 d–f).

Description: Body elongated, females average body length 5.9 mm (range: 5.5–6, n= 15); length: width ratio 3.1:1; males average body length 6.1 mm (range: 6–6.5, n=15), length: width ratio 3:1; bright black, sub-parallel sides; moderately abundant thick erect black hairs and abundant fine, gray decumbent pilosity on the dorsal surface; scutellum with dense, fine, decumbent light gray pilosity; pronotum and elytra with abundant coarse punctures; antennae and legs reddish or dark testaceous; femur and tibiae with dense, fine, decumbent light gray pilosity.

Head: Including the eyes, as wide as distal margin of pronotum (1:1); front slightly depressed between the eyes; frontoclypeal region slightly prolonged and narrowed toward the apex; antennae longer than the length of the pronotum (1.6:1); female antennomeres 5–10 slightly serrated ( Fig. 2a View FIGURE 2 ); males antennomeres 5–10 moderately serrated ( Fig. 3a View FIGURE 3 ).

Thorax: Pronotum slightly wider than long (1.2:1), and moderately convex transversely, widest at the middle; distal, lateral and basal margins are well marked, lateral margin is slightly flattened, basal margin narrower than humeral region (0.6:1). Elytra longer than wide (4.6:1), with a moderately marked humeral angle; subparallel sides that are slightly rounded towards to apex; disc slightly convex, slightly marked subapical angle; wide, pilose epipleura, internal margin with scarce denticles, and sides converging at the apex. Legs: elongated, slender, moderately scarce bristles in the external margin of the tibiae; tarsomeres with scarce, fine ventral spines; toothed claws.

Abdomen: female: Ventrite 5 with moderately concave distal margin; ventrite 6 and last tergite not fused; ventrite 6 slightly emarginated at the distal margin, spiculum ventral fine, longer than ventrite 5 (1.5:1); last tergite elongated and moderately rounded at the distal margin, strongly emarginated basal margin ( Fig. 2b View FIGURE 2 ); Genitalia: membranous ovipositor with a sub-rectangular sclerite on the ventral laminae, shorter than oblique baculi (0.6:1); ventral baculi longer than oblique baculi (2:1) and slightly widened at the base; fine, long proctiger baculi, longer than ventral baculi (1.5:1) ( Fig. 2c,d View FIGURE 2 ); ventral and dorsal laminae with scarce pubescence.

Males: Ventrite 1 with a central process at the middle, like a small hook, close to the basal margin; ventrite 5 strongly emarginated at the distal margin; ventrite 6 and last tergite fused like a subconical structure; ventrite 6 emarginated at the distal margin with two lateral pointed projections; basal margin emarginated at the middle ( Fig. 3b View FIGURE 3 ); last tergite projected at the apex ( Fig. 3b View FIGURE 3 ); segment 9 has fine tergum and sternal arms, and a short apodeme ( Fig. 3c View FIGURE 3 ); Genitalia: sclerotized parameres, sides subparallel, apex truncate, slightly emarginated in the middle ( Fig. 4a,b View FIGURE 4 ); tegminal arms moderately thick, strongly curved at base; tegminal plate broad with a dorsal elevated fold at the midline, strongly emarginated at the distal margin, slightly projected on the apodeme; wide and securiform apodeme, consisting of two parallel laminae ( Fig. 4c View FIGURE 4 ). Median lobe is subcylindrical, sclerotized, elongated, and strongly curved at the base; slightly widened pre-apically; pointed apex; wide, subapical phallotreme; long apodeme ( Fig. 4 View FIGURE 4 d–f).

Distribution. ARGENTINA: Catamarca Province: Catamarca (MNHN) 1♀; (MLPA) 2♀, 1♁, Andalgal (MLPA) 4 ♀, 5♁. Tucumán Province: Taf del Valle (IFML) 4 ♀, 6♁; Tucumán (IFML) 4♀, 4♁. Salta Province: Salta (MLPA) 5♀, 2♁; Cuesta del Obispo (JEBC) 2♀, 1♁; Rosario de Lerma (JEBC) 1♀; Chorrillos (JEBC) 1♀. Jujuy Province: Laguna del Yala (IFML) 8♀, 28♁. BOLIVIA: Santa Cruz Province: Santa Cruz (IFML) 1♀, 4♁.

According to the collection data of the material reviewed in this study, the geographic distribution of Astylus alboscutellatus corresponds to the Monte and Puna Provinces of the South American Transitional Zone in the Andean region, and to the Chacoan Province in the Chacoan dominion of the Neotropical region ( Morrone 2014, 2018).