Aclista scutellaris
Creators: name: Macek, Jan
Publisher: name: Zenodo
Year: 2007
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Diapriidae
Aclista
Aclista scutellaris

description: Aclista scutellaris (Thomson, 1859)   
(Figs. 7, 16, 23, 32)  
 Acoretus scutellaris Thomson, 1859: 159.   
 Aclista scutellaris: MARSHALL (1873): 9.   
 Xenotoma scutellaris: KIEFFER (1907): 24; KIEFFER (1910a): 604.   
 Xenotoma (Xenotoma) scutellaris: KIEFFER (1910b): 34; KIEFFER (1916): 517, 523.   
 Xenotoma scutellaris: MORLEY (1923): 231.   
 Aclista scutellaris: NIXON (1957): 569; KOZLOV (1978): 569; JOHNSON (1992): 42.   
 Aclista (Acoretus) bispinosa Wall, 1967: 153, syn. nov.   
 Type locality: Sweden, Småland.   
 Type material examined. Aclista scutellaris. HOLOTYPE: J, ‘Sm. // Holotypus 1859 / Acoretus scutellaris Thomson’ (NHRS).   
 Additional material examined: CZECH REPUBLIC: BOHEMIA centr., Praha – Krč (5952), 13.ix.1984, 132 JJ 14 ♀♀, Praha – Nebušice (5852), 31.v.1982, 7 spec. BOHEMIA mer.: Purkarec (6852), 11.vi.1982, 4 spec.; Stráž nad Nežárkou (6955), 22.vi.1986, 1 spec. BOHEMIA bor.: Úhošťany (5645), 3.vi.1982, 2 spec. BOHEMIA or.: Orlické hory Mts., Kačerov (5764), 5.viii.1994, 2 spec., Bukačka Nature Reserve (5664), 16.vii.1997, 2 spec.; Králický Sněžník Nature Reserve, Mlýnský potok brook (5866), 22.viii.2001, 5 spec. MORAVIA mer.: Bítov (7060), 22.vi.1983, 1 spec. SLOVAKIA centr.: Nízké Tatry Mts.: Heľpa (7185), 31.vii.1984, 1 spec., Ohniště Nature Reserve (7083), 4.viii.1984, 1 spec.; Poľana Mts. (7382), 2.viii.1986, 1 spec.; Silica (7489), 15.v.1985, 2 spec.; Gombasek (7588), 17.v.1985, 1 spec. SLOVAKIA occ.: Nitra district, Zobor hill (7674), 23.v.1987. 1 spec.; all J. Macek lgt. & det. (NMPC). AUSTRIA: STEIERMARK, Gragger Schlucht, Neumarkt, 900-1000 m a.s.l., 10.vii.1971, 1 spec., Fischer lgt., J. Macek det.(NHMW). POLAND centr.: Belsk district, Modrzewina Nature Reserve, 28.ix.1982, 1 spec., Ekipa lgt., J. Macek det. (NMPC). HUNGARY bor.: Pilis Mts., Piliscsaba, 21.viii.1980, 4 spec., J. Macek lgt. & det. (NMPC).   
 Diagnosis. Mandibles short; malar space smooth, without malar keel; antennae 14-segmented in females, 15-segmented in males; pronotal shoulders angular; epomia developed; inner plicae of propodeum converging, not projecting posteriorly; radial cell closed, 2.5 times as long as marginal vein; petiole cylindrical, smooth with longitudinal ribs; basal sculpture of macrotergite with long medial furrow and short adjacent striation; male protibia with several modified setae within unmodified short pubescence.   
 Description. Female. Length: 2.6-2.8 mm. Dark brown; head and mesosoma darker than gaster; antennae and appendages stramineous.   
 Head strongly transverse in dorsal view with prominent antennal sockets and erect pubescence; antennal sockets with slight cleft between toruli anteriorly, malar space smooth, genae granulose; malar keel absent; vertex highly convex; temples strongly converging posteriorly; ocelli large; transverse eye diameter a little shorter than malar space; eyes pubescent; head in lateral view higher than long; head in frontal view subtriangular with smooth face; antennal sockets smooth below; subantennal furrows short, distinct; epistomal sulcus developed; tentorial pits surrounded by deep hollows; mouth aperture shorter than malar space; clypeus unmodified (lateral view), smooth; mandibles prominent, short sickle-shaped. Antenna 14- segmented; proximal flagellomeres subcylindrical, distal ones suboval.   
 Mesosoma convex, as wide as head, with long, contiguous pubescence; pronotal collar indistinct, pronotal shoulders angular; epomia developed; lateral pronotum strongly impressed, concave, smooth and lustrous, not perceptible from above; lateral rim of pronotum indistinct; mesoscutum convex; notauli percurrent, diverging posteriorly; scutellum slightly convex, smooth with large, rectangular anterior scutellar pit (ASP); axillar depressions smooth with a very fine tuft of pubescence; mesopleuron smooth with large scrobe in middle; metascutellum rounded; lateral sides of metanotum smooth; propodeum subquadrate with subtrapezoidal, sparsely pubescent dorsal surface, posteriorly bordered by distinct, slightly concave ledge; medial keel of propodeum simple; inner plicae of propodeum converging, not projecting posteriorly. Wings slightly infusacate, marginal vein distinctly shorter than parastigma (= abscissa between marginal vein and basalis); radial cell closed, 2.5 times as long as marginal vein; stigmal vein slightly oblique and shorter than marginal vein.   
 Metasoma. Petiole cylindrical, smooth with longitudinal ribs, 1.5 times as long as wide; gaster fusiform, pubescent, pygidium slightly upcurved apically; base of macrotergite slightly wider than petiole; basal sculpture of macrotergite with long medial furrow and short adjacent striation; segments preceding pygidium very short and closely abutted; pygidium very short, slightly upraised.   
 Male. Differs from the female by the cylindrical flagellomeres, modified flagellomere 1, and stiff intermittent bristles on the inner side of the fore tibia.   
 Variability. The species varies in the shape and length of flagellomeres in females (oval to suboval) and the shape of the emargination of flagellomere 1 (shallow to deep).   
 Differential diagnosis. The species is closest to A. bitensis, from which it differs by the complete absence of malar keel.   
 Bionomics. Flight period May to September; hosts unknown.   
 Distribution. Sweden (NIXON 1957), Switzerland (WALL 1967), Czech Republic (MACEK 1989). New records: Austria, Hungary, Poland and Slovakia.   
 Remarks. This species remained essentially unrecognizeable until NIXON (1957) revised the type and provided a drawing of the front tibia, illustrating the characteristic heterogeneous pubescence. WALL (1967) disagreed with NIXON’ s (1957) concept of A. scutellaris (Thomson, 1859) and proposed for it a new name, Aclista bispinosa Wall, 1967. Based on the examination of the type, Nixon’s concept is correct and thus A. bispinosa is a junior synonym of A. scutellaris. Association of both sexes is based on the comparison of a large series of specimens from Praha – Krč, Czech Republic (see Material examined).
description: Published as part of Macek, Jan, 2007, Revision of Central European species of the Aclista scutellaris complex (Hymenoptera: Diapriidae), pp. 211-228 in Acta Entomologica Musei Nationalis Pragae 47 on pages 214-215, DOI: 10.5281/zenodo.5328323