Dolichosoma (Dolichosoma) lineare ( Rossi, 1794 )

Miao, Jialin, Liu, Haoyu, Tong, Junbo & Yang, Yuxia, 2024, First record of the genus Dolichosoma Stephens (Coleoptera, Dasytidae) from China, with two newly-recorded species, Biodiversity Data Journal 12, pp. e 129639-e 129639 : e129639-

Dolichosoma (Dolichosoma) lineare ( Rossi, 1794)

Lagria linearis Rossi, 1794 - Rossi 1794: 92 (type locality: Italy); Stephens 1830: 320; Redtenbacher 1858: 547; Kiesenwetter 1863: 642; Thomson 1864: 146; Kiesenwetter 1867 a: 119; Kiesenwetter 1867 b: 137; Mulsant and Rey 1868: 269; Seidlitz 1891 a: 489; Seidlitz 1891 b: 522; Schilsky 1897: nr. 26; Reitter 1911: 289; Pic 1918: 2; Pic 1924: 57, 83; Porta 1929: 123; Pic 1937: 106; Horion 1953: 140; Kaszab 1955: 118; Allenspach and Wittmer 1979: 110; Lohse 1979: 89; Majer 1990: 97; Constantin and Klausnitzer 1996: 196; Sparacio 1997: 106; Bahillo de la and Lopez-Colon 2002: 145; Liberti and Focarile 2005: 29, 35; Mayor 2007: 407.

Tillus filiformis Panzer, 1799 - Panzer 1799: 17; Illiger 1801: 84.

Dolichosoma filum Fairmaire, 1860 - Fairmaire 1860: 630; Constantin 2007: 167.

Dolichosoma subdensatum Mulsant and Rey, 1868 - Mulsant and Rey 1868: 273; Schilsky 1897: nr. 26.

Dolichosoma submicaceum Mulsant and Rey, 1868 - Mulsant and Rey 1868: 274; Schilsky 1897: nr. 26.

Dolichosoma subnodosum Mulsant and Rey, 1868 - Mulsant and Rey 1868: 274; Schilsky 1897: nr. 26.

Dolichosoma tenuiforme Horn, 1880 - Horn 1880: 150–151.

Materials

Type status: Other material. Occurrence: recordedBy: Zhengzhong Huang; individualCount: 5; sex: 3 males, 2 females; lifeStage: adult; occurrenceID: E8F84560-5E03-5FD3-A8C4-19349CEBFAEF; Location: country: China; stateProvince: Xinjiang; county: Burjin; locality: Hemu ; verbatimElevation: 1333 m; Event: year: 2023; month: 6; day: 16; Record Level: institutionID: Museum of Hebei University; institutionCode: MHBU

Description

Male (Fig. 5 A). Body extremely slender, length 4.4–5.2 mm, width 0.7–0.8 mm.

Body green with strong metallic lustre. Antennae black, antennomeres 1 green with metallic lustre, 2 yellowish-brown, 2–11 without metallic lustre. Body finely and shallowly punctate on surface, sparsely covered nearly scale-like, short and recumbent whitish pubescence and scattered with only a few erected black setae on head and elytral apex (usually not on pronotum).

Head width across eyes 1.1–1.2 times as wide as pronotum. Antennae serrate and slightly longer, extending to basal 1 / 5 length of elytra when inclined, antennomere 2 globular, 3–10 triangular, nearly 1.0–3.0 times as long as wide, progressively increased in length, 10 longest and ca. 2.5–2.7 times longer than 3, 11 fusiform and pointed at apices. Ultimate palpomere normal in size and approximately cylindrical, about 3.0 times longer and 1.1 times wider than the penultimate palpomere.

Pronotum parallel-sided, 1.3–1.5 times as long as wide, with anterior margins nearly straight, posterior margin feebly bisinuate, anterior and posterior angles widely rounded.

Elytra parallel-sided, tapered at apices, 4.6–4.9 times longer than wide at humeri, 5.9–6.2 times longer than pronotum.

Tarsal claws (Fig. 2 D – F) slightly asymmetrical in the structure, each protarsal inner claw without basal appendicle, while weakly developed on outer claw, meso- and metatarsal outer claws without basal appendicles, while weakly developed on inner claws.

Ultimate abdominal ventrite (Fig. 6 A) 1.6–1.7 times as wide as long, largely and roundly emarginate in middle of posterior margin, membranous behind the middle emargination, rounded at apices of posterior-lateral angles, present with short central process at anterior margin, surface covered with short black setae along lateral margins. Pygidium (Fig. 6 B) 1.1–1.3 times longer than wide, feebly narrowed posteriorly, hardly emarginate in middle of posterior margin, largely and triangularly emarginate in middle of anterior margin, with antero-lateral angles obviously protruding, surface covered with a few long black setae along lateral margins. Aedeagus: tegmen (Fig. 6 C) nearly elliptic, strongly narrowed basally and round at base, parallel-sided, shortly bilobed and lateral lobes covered with a few short setae; median lobe (Fig. 6 D) strongly bent dorsally, with apical limb at an angle of 90 ˚ with basal limb, apical limb clearly longer than basal limb, feebly widened apically, then abruptly narrowed and pointed at apex; internal sac (Fig. 6 D – E) short, fitted with two lines of large black spines at the apical part and several tiny spines at the base. Spiculum gastrale (Fig. 6 F) Y-shaped.

Female (Fig. 5 B). Similar to male, but body larger, 5.8–6.4 mm in length, width 0.9–1.0 mm; antennae slightly shorter, extending to posterior margin of pronotum when inclined. Elytra much longer, about 5.1–5.2 times as long as wide, 6.7–6.8 times longer than pronotum. Ultimate abdominal ventrite (Fig. 7 A) longer, strongly narrowed posteriorly, hardly emarginate in middle of posterior margin, present with a longer central process at anterior margin. Pygidium (Fig. 7 B) feebly narrowed posteriorly, hardly emarginate in middle of anterior margin, with antero-lateral angles obviously protruding. Ovipositor (Fig. 7 C) stout and membranous, gonostylus short and conical, transverse coxital baculus short and oblique, baculus helical and much longer than transverse coxital baculus.

Diagnosis

This species is very similar to D. (Dolichosoma) simile (Brullé, 1832) and can be distinguished by the combination of following characters: pronotum not covered with erected black setae on surface; elytra tapered at apices, present with 2–3 weakly developed, but visible longitudinal costae. Unlike in D. simile , the pronotum is covered with erected black setae on the surface; elytra are rounded at apices, absent with visible longitudinal costae ( Liberti 2009).

Distribution

China (Xinjiang, Figs 8 , 9 ), Andorra, Austria, Belgium, Bahrain, Belarus, Croatia, Russia (throughout the temperate zone of country from Saint Petersburg to Vladivostok), Czech Repubic, Denmark, Estonia, Great Britain, Finland, France, Germany, Hungary, Italy, Latvia, Lithuania, Netherlands, Norway, Poland, Romania, Slovakia, Spain, Sweden, Switzerland, Ukraine, East Siberia and Kazakhstan.

Figures

Figure 2. Male tarsal claws of Dolichosoma species, frontal views: A, B, C D. (Dolichomorphus) femorale Morawitz, 1861; D, E, F D. (Dolichosoma) lineare (Rossi, 1794). A, D protarsal claws; B, E mesotarsal claws; C, F metatarsal claws. Scale bars: 0.1 mm.

Figure 5. Habitus of Dolichosoma (Dolichosoma) lineare (Rossi, 1794), dorsal view: A male; B female. Scale bars: 1.0 mm.

Figure 6. Dolichosoma (Dolichosoma) lineare (Rossi, 1794), male: A ultimate abdominal ventrite (apical sternite), ventral view; B pygidium (apical tergite), dorsal view; C tegmen, ventral view; D median lobe, ventral view; E median lobe, lateral view; F spiculum gastrale, ventral view. Scale bars: 0.2 mm.

Figure 7. Dolichosoma (Dolichosoma) lineare (Rossi, 1794), female: A ultimate abdominal ventrite (apical sternite), ventral view; B pygidium (apical tergite), dorsal view; C ovipositor, ventral view. Scale bars: 0.2 mm.

Figure 8. Distribution map of Dolichosoma species in China.

Figure 9. Macrohabitat of Dolichosoma (Dolichosoma) lineare (Rossi, 1794) in Hemu Township, Burjin County, Xinjiang Autonomous Region of China. Photographed by Dr. Zhengzhong Huang in June 2023.