Sadoletus melasmus Ban 2018, sp. nov.
Creators: name: Ban, Teruaki
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Heterogastridae
Sadoletus
Sadoletus melasmus

description: Sadoletus melasmus sp. nov.
(Figs. 8–9, 15, 18, 25–29)
Type Materials. Holotype: ♀, THAILAND: 12°40'14“–30“N, 101°24'50“–52”E, alt. 452–552 m, Near Rayong, Rayong Prov., 17.III.2015, Teruaki Ban (TUA). Paratypes: THAILAND: 1 ♂ 2 ♀, 12°49'14.5“N, 102°07'40.6”E, alt. 66 m, Krathing Country Resort, Chanthaburi Prov., 14.III.2015, Teruaki Ban (TUA); 1 ♂ 2 ♀, same locality, 15.III.2015, Teruaki Ban (TUA).
Diagnosis. Recognized among congeners of Sadoletus by the following characters: Head, anterior lobe of pronotum, basal half of scutellum and apical third of corium black (Figs. 8, 9); labium exceeding posterior margin of prothorax (Fig. 15); posterior lobe of pronotum pale yellow, with submedian longitudinal band and 2 dark brown spots at lateral angle (Figs. 8, 9); corium white in basal two-thirds and blackened in apical third, with black spots around inner angle of corium and claval commissure (Figs. 8, 9); clavus white; femora and tibiae yellow and white, with brown or yellow annulations, metafemur and metatibia with brown annulations (Figs. 8, 9); abdominal sternum black; ovipositor strongly curved laterally (Fig. 18); posterior margin of pygophore and cuplike sclerite fused together (Fig. 25); paramere sickle-shaped at apex (Fig. 26).
Description. Female (holotype): Venter almost black. Short decumbent setae on body silvery. Punctures on pronotum, scutellum, and corium dark brown. Head (Fig. 9) black. Clypeus pale yellow. Antenna generally brownish yellow, apical three quarters of segment IV tinged with dark brown. Labium dark brown; segment III and basal three quarters of segment IV brownish yellow. Pronotum (Fig. 9) black in anterior lobe and pale brownish yellow in posterior lobe, posterior lobe with longitudinal pale stripe along meson and 2 dark brown longitudinal band and 2 dark brown markings at around lateral angle. Venter of mesothorax and metathorax black; peritreme brown. Scutellum (Fig. 9) black in basal half and brown in apical half. Apical half of scutellum with pale longitudinal stripe along meson. Corium (Fig. 9) white in basal two-thirds and black in remaining part; black circular spot at inner angle; clavus white, with longitudinal black stripe along claval commissure; hemelytral membrane hyaline, with oval brownish spot at middle. Coxae dark brown; trochanters, femora and tibiae pale yellow; metafemur and metatibia with brown annulations; tarsomere I pale yellow, tarsomeres II and III pale brown. Abdomen (Fig. 15) black; each laterotergite entirely reddish brown.
Body (Fig. 9) 3.1 times as long as width across humeri. Head (Fig. 9) 1.7 times as wide as its length, covered with both rough and fine punctures; tylus tumid upwards; clypeus weakly projecting anteriad; juga with decumbent setae. Eyes occupying nearly half area of head in lateral view, not reaching anterior margin of pronotum. Antennae covered with suberect setae; proportional lengths of segments I to IV 1.0: 1.7: 1.6: 2.4. Labium slightly exceeding posterior margin of prothorax, not reaching mesocoxae; proportional lengths of segments I to IV 1.4: 1.4: 1.1: 1.0.
Pronotum (Fig. 9) a little more than 1.4 times as wide as its length, nearly trapezoidal, lacking collar, covered with dense punctures, and with lateral margin of anterior lobe weakly serrate; posterior lobe 1.4 times as long as anterior lobe, slightly more convex than anterior lobe; posterior margin almost straight. Venter of prothorax, mesepisterna and metepisterna covered with decumbent setae. Scutellum (Fig. 9) triangular, weakly tumid transversely in basal half, covered with long suberect setae. Hemelytra (Fig. 9) exceeding apex of abdomen; apical margin of corium as long as claval suture. Profemur moderately expanded, armed with a spine ventrally at about apical third; tibiae and tarsi sparsely covered with long erect setae.
Abdomen wider than hemelytral width; sternum covered with decumbent setae. Ovipositor (Fig. 18) strongly curved laterally, reaching posterior margin of sternite VI, approximate oviposital length 0.4 mm; the two hemiventrites of the medially completely bisected sternite VII are short, therefore posterior margins of sternites III–V straight, posterior margin of sternite VI weakly sinuate (Fig. 18).
Spermatheca (paratypes) as in Fig. 29.
Male (paratypes): Male resembles female in general appearance. Body (Fig. 8) evidently narrower; coloration of posterior lobe of pronotum and each leg paler than female; pygophore (Fig. 25) nearly spherical in dorsal view, covered with suberect setae; dorsal sinus of posterior aperture one quarter as wide at middle as pygophore, without collar along anterior margin; posterior margin of pygophore and cuplike sclerite fused together; paramere (Fig. 26) robust, twisted at basal third, sickle-shaped at apex, covered with several erect setae, sensory processes projecting laterally; phallosoma (Figs. 27, 28) nearly twice as long as its width in ventral view, wrinkled at apical margin.
Measurements [♂ (n=2) / ♀ (n=5), value for holotype female in parentheses]. Body length 4.55–4.6 / 4.61– 5.2 (4.97); body height between coxae and dorsum 1.15–1.2 / 1.18–1.38 (1.3); head length 0.7–0.75 / 0.7–0.83 (0.75), head width across eyes 1.25–1.3 / 1.23–1.38 (1.31); length of antennal segments I–IV respectively 0.33– 0.34 / 0.31–0.35 (0.34), 0.59–0.63 / 0.52–0.65 (0.58), 0.58–0.59 / 0.5–0.6 (0.53), 0.85–0.86 / 0.76–0.88 (0.81); length of rostral segments I–IV respectively 0.41–0.43 / 0.41–0.43 (0.42), 0.43–0.44 / 0.44–0.45 (0.44), 0.33–0.35 / 0.31–0.35 (0.35), 0.3–0.31 / 0.29–0.33 (0.31); mesal pronotal length 1.08–1.13 / 1.06–1.31 (1.18); posterior pronotal width 1.38–1.4 / 1.41–1.73 (1.59); mesal scutellal length 0.74–0.76 / 0.76–0.96 (0.81); basal scutellal width 0.74–0.78 / 0.76–1.0 (0.88); hemelytral length 2.85–2.9 / 2.96–3.38 (3.25); maximum width across hemelytra 1.35–1.43 / 1.44–1.73 (1.53).
Distribution. Thailand (Chanthaburi Prov., Rayong Prov.).
Etymology. The species epithet is the Greek adjective “ melasmus ” (meaning black spot) referring to characteristic black to dark brown spot at inner angle of corium.
Remarks. This new species is most similar in general appearance to S. bakeri Bergroth, S. montanellus Bergroth and S. ryukyuensis Ban et Ishikawa, but it can be distinguished from the latter by a combination of the following characters: Body length more than 4.5 mm (in S. montanellus, 3.0 mm); antennal segment II less than twice as long as segment I (vs. antennal segment II more than twice as long as segment I); labium slightly exceeding posterior margin of prothorax, not reaching mesocoxae (vs. at least reaching mesocoxae); posterior lobe of pronotum pale brownish yellow (in S. montanellus, dark brown); coxae black (in S. ryukyuensis, coxae brown); ground color of femora and tibiae pale yellow (vs. femora and tibiae yellowish brown); apical third of corium black in both sexes (in S. ryukyuensis, apical third of corium white in female); hemelytra with dark markings at inner angle of corium and hemelytral membrane (vs. hemelytra lacking dark marking at inner angle of corium and hemelytral membrane); abdominal sterna black (in S. bakeri abdominal sterna reddish brown).
Biological notes. The specimens were collected from trees of Ficus sp. in mountainous forests and the open forest adjacent to a resort hotel, with several other heterogastrid and rhyparochromid species.
description: Published as part of Ban, Teruaki, 2018, The lygaeoid bug family Heterogastridae (Hemiptera: Heteroptera: Lygaeoidea) from Laos and Thailand, with descriptions of three new species, pp. 51-67 in Zootaxa 4446 (1) on pages 57-60, DOI: 10.11646/zootaxa.4446.1.4, http://zenodo.org/record/1437384