Caystrus pseudobrunnescens Linnavouri
Creators: name: Ahmad, I.
name: Zahid, M.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Pentatomidae
Caystrus
Caystrus pseudobrunnescens

description: C. pseudobrunnescens Linnavouri
(Fig. 2)
Caystrus brunnescens Linnavouri 1972: 400, 413 (nec. Agabotus brunnescens Distant 1884) Caystrus pseudobrunnescens Linnavouri 1974: 402, 408-409; 1975: 35; 1982: 76.
Colouration and general shape
Body pale with thick brown punctures; eyes brownish black, ocelli pinkish; membrane of hemelytra hyaline.
Head
Distinctly broader than long; anteocular distance shorter than remainder of head; paraclypei broad, longer than clypeus not enclosing clypeus, lateral margins slightly sinuate, apex of paraclypei round; antennae with basal segment slightly shorter than head apex, 2 nd segment shorter than 3 rd, 5 th longest, length of antennal segments I 0.5 (0.5- 0.55), II 0.9, III 1.2 (1.15-1.2), IV 1.45 (1.35-1.45), V 1.5, antennal formula 1<2<3<4<5; labium just reaching hind coxae,1 st equal to 4 th,2 nd longest, length of segments I 0.7 (0.7-0.8), II 1.1 (1.1-1.3), III 0.9 (0.9-1.0), IV 0.7,labial formula I=IV<III<II; anteocular distance 0.75 (0.75-0.85); remainder of head 1.0; width of head 2.45; interocular distance 1.4 (1.30-1.40); interocellar distance 0.9.
Thorax
Pronotum slightly less than 2.5x broader than its length, anterior margin distinctly broader than head width across the eyes, anterior angles toothed, humeral angles sub-acutely produced, lateral margins sinuate, length of pronotum 2.14 (2.15- 2.4),width 5.3 (5.3-5.6); scutellum with short apical subacute lobe, length of scutellum 4.15 (4.15-4.4), width 3.4 (3.4-3.5); metathoracic scent auricle (Fig. 2b) with peritreme lobe-like reaching ½ distance of evaporatoria, apex round, anterior margin of peritreme concave, posterior margin convex, ostiole slit-like; base scutellum-apex clavus 3.0 (3.0-3.1); apex clavus-apex corium 2.1(2.1-2.4); apex corium-apex abdomen including membrane 1.6(1.6-1.9); apex scutellum-apex abdomen including membrane 2.65 (2.65-3.2).
Abdomen
Convex beneath; connexiva exposed at repose; posterior margin of 7 th abdominal sternum medilly concave, lateral margins slightly sinuate with acute angles, abdomen shorter than membrane of hemelytra. Total length 10.7 (10.7-11.85).
Male genitalia
Pygophore (Fig. 2C) rectangular, dorso-median surface concave with a large bilobed process at inner lateral margins, lateral lobe truncately produced, ventro-median surface bilobed; paramere (Fig. 2D) somewhat F-shaped, outer margin sinuate, apex truncate, a bunch of hairs present at inner lobe-like process; aedeagus (Fig. 2E,F) with theca with out thecal appendage, vesica large, curved, pair of largely membranous ventral conjunctival appendages, pair of thorn-like bilobed dorso-lateral conjunctival appandages.
Female genitalia
Female terminalia (Fig. 2G) with triangular moderate 1 st gonocoxae, inner and posterior margins sinuate, slightly separated; 9 th paratergites flipper-like, large, just reaching fused posterior margins of 8 th paratergites; later sinuate; 2 nd gonocoxae with posterior margin slightly concave; posterior margin of proctiger concave; spermatheca (Fig. 2H) with balloon-like median dilation, proximally encircled by a sclerotized ring, proximal spermathecal duct about 2x longer than distal spermathecal duct, pump region tubular with sinuated lateral margins, bulb spherical with two finger-like processes.
Material examined 1 male Zair: Ituri, Foret de Kawa, 15.4.1929 leg A. Collart; 1 female Zair: Ituri, Foret de Kawa, 13.4.1929, A. Collart NHM Tervuren, loged at Nat. Hist. Mus. Stockholm, Sweden.
Comparative note
It is most closely related to C. quadrimaculatus in having body pale brown with thick brown punctures, of moderate size and dorso-median surface of pygophore deeply concave but it could easily be separated from C. quadrimaculatus by its scutellum with short apical sub-acute lobe, outer margin of paramere sinuate, curved near apex with round tip in contrast to scutellum with short, apically round lobe, outer margin of paramere roundly curvate, apex of blade sharply truncate but medially slightly concave and distally acutely spinously produced in C. quadrimaculatus
description: Published as part of Ahmad, I. & Zahid, M., 2009, Resurrections and redescriptions of Caystrus marginiventris (Stål), C. trivalis (Gerstaecker) and C. pseudobrunnescens Linnavuori (Hemiptera: Pentatomidae: Pentatominae), key to this complex and their cladistic relationships, pp. 305-312 in Pakistan Journal of Zoology 41 on pages 307-309