Mormoschema immaculatum ( Distant, 1900 )

Kment, Petr & Cassis, Gerasimos, 2023, Rehabilitation of Mormoschema (Hemiptera: Heteroptera: Pentatomidae): generic status restituted and tribal placement revised, Acta Entomologica Musei Nationalis Pragae 63 (2), pp. 397-412 : 402-406

Mormoschema immaculatum ( Distant, 1900) , comb. restit.

Tolumnia immaculata Distant, 1900:168 (original description). Syntypes: Ceylon; India: Nilgiri Hills, Kotagira (BMNH).

Tolumnia immaculata : DISTANT (1902): 155 (original description repeated); BERGROTH (1908): 162 (catalogue); KIRKALDY (1909): 51 (catalogue, distribution); DISTANT (1918): 130 (original combination restored); CHATTERJEE (1934): 12 (faunistics,associated plant);CHAN- DRA (1953): 96 (faunistics); MATHUR & SINGH (1960): 66 (associated plant); ZAIDI (1995): 512 (key to species), 513: figs 1A–G (redescription; illustrations of habitus, external scent efferent system, genital capsule, paramere, penis, external female genitalia and spermatheca). Mormoschema immaculatum : BREDDIN (1909): 270 –271 (new combination); KIRKALDY (1909): 365 (catalogue).

Type material examined. SYNTYPES: INDIA: 1 ♀, ‘Kotagiri [hw] // Atkinson / Coll. / 92–6. [p] // NHMUK 013589968 [p] // ♀ ’ [p] ( BMNH, pinned; Figs 5–7 ); 1♀, ‘Kotagiri [hw] // Atkinson / Coll. / 92–6. [p] // ♀ ’ [p] ( BMNH, pinned); 1 ♀, ‘Nilgiris / (Hampson) [hw] // Distant Coll. / 1911–383 [p] // ♀ ’ [p] ( BMNH, pinned); 1 J, ‘ immaculata / Dist. [hw] // Nilgiri / (Hampson [sic!, p] // Distant Coll. / 1911–383 [p] // J’ [p] ( BMNH, pinned). SRI LANKA: 1♀, ‘Type [p, round label with red circle submarginally] // Pundaloya / Ceylon [p] II [hw] // Ceylon / Green Coll. / 91–26 [p] // immaculata / Dist. [hw] // 101 [hw, grey label] // BRIT. MUS. / TYPE No. / HEM [p] 993 [hw, pink label] // ♀ ’ [p] ( BMNH, pinned); 1 ♀, ‘101 [hw, grey label] // Ceylon / Green Coll. / 91–26 [p] // ♀ ’ [p] ( BMNH, pinned); 2 ♀♀, ‘Ceylon / (Lewis) [p] // Distant Coll. / 1911–383 [p] // ♀ ’ [p] ( BMNH, card-mounted); All the syntypes bear the following two labels: ‘ SYNTYPUS / TOLUMNIA / IMMACULATA / Distant, 1900 stat. restit. / labelled: SALINI & KMENT 2023 ’ [p, red label] and ‘ MORMOSCHEMA / IMMACULATUM / ( Distant, 1900) / det. SALINI & KMENT 2023 ’ [p].

Additional material examined. The material was identified by Salini unless stated otherwise. INDIA: KARNATAKA: Nandi Hills, 1478 m a.s.l., 13°38′N 77°70′E, 6.ix.2013, 1 J, T. Vinayaka lgt. ( UASB); Coorg, Thadiyandamal hills, 12°33.729′N 75°37.479′E, 1328 m a.s.l., 12.iv.2011, 1 ♀, H. M.Yeshwanth lgt.( UASB); Bengaluru,Attur, 19.ix.2018, 5JJ, ex. Buddleja asiatica, G. Prabhu lgt. ( NIM);Yelahanka,Attur, 10.vii.2019, 1 ♀, Salini S. lgt.( NIM); Chikballapur, Mysore, i.1915, 1J, T.V.Campbell coll., Pres. by Imp. Bur. Ent., Brit. Mus. 1921–494, B. Uvarov det., P. Kment revid. ( BMNH); Chikkballapura + KK + Nilgiris, Nilgiri Hills, v.1915, 3♀♀, T.V.Campbell, T. V.Campbell Coll., Brit.Mus.1930–595, P. Kment det. ( BMNH); South India, T. [?], iv.1915, 3 JJ 3 ♀♀, T. V. Campbell Coll., Brit. Mus. 1930–595, P. Kment det. ( BMNH); South India, T. [?], v.1915, 2 ♀♀, T. V. Campbell Coll., Brit. Mus. 1930–595, P. Kment det. ( BMNH); South India, K.K., 5000 ft [= 914.4 m a.s.l.], v.1914, 1 J 1 ♀, T. V. Campbell Coll., Brit. Mus. 1930–595, P. Kment det. ( BMNH); South India, N. Dg, x.1913, 1 J 2 ♀♀, T. V. Campbell Coll., Brit.Mus. 1930–595, P.Kment det.( BMNH); South India, N. Drug, x.1913, 1 J, T. V. Campbell Coll., Brit. Mus. 1930–595, P. Kment det. ( BMNH). TAMIL NADU: Salem, Yeracaud, 28.ix.2021, 2 JJ 2 ♀♀, ex. Scrophularia sp. , K. V. Maruthi lgt. ( NIM); Kodaikanal, Pullney Hills, 3 JJ, Distant Coll. 1911–383 (2 JJ BMNH, 1 J ISNB); S. India, Nilgiri Hills, 1J 8♀♀, 1903–63, P.Kment det. ( BMNH); S. India, Nilgiri Hills, 1 J 8 ♀♀, T. V. Campbell, Ex Coll. E. A. Butler, B. M. 1926–171, P. Kment det. (1J 7♀♀ BMNH, 1♀ NMPC); S. India, Nilgiri Hills, 1♀, T. V. Campbell, Distant det.?, P. Kment revid. ( NHRS); S. India, Coromandel Coast, Tranquebar, iv.1947, 1 J 1 ♀, P. S. Nathan lgt., P. Kment det. ( NMPC). SRI LANKA: Ceylon, 1♀, Felder [lgt.] ( NHMW); Colombo, 29.iii.1929, 9 JJ 3 ♀♀, Pres. by Imp. Bur. Ent. Brit. Mus. 1930–197, P. Kment det. (8 JJ 3 ♀♀ BMNH, 1 J NMPC); Ceylon, Kandy, 5-09, 1 ♀, Distant Coll., B.M. 1911–383 ( BMNH); Namunukuli, ii.1910, 1 J 3 ♀♀, Distant Coll. 1911–383, P. Kment det. ( BMNH); Ceylon, Nuwara Eliya, 6,234 –8,000 ft [= 1900.1–2438.4 m a.s.l.], 8.–11.ii.[18]82, 3 JJ 1 ♀, G. Lewis, 1910–320, P. Kment det. ( Figs 8–21 ) (2 JJ 1 ♀ BMNH, 1 J NMPC); Ceylon,Anuradhapura, 1 J, W. Horn lgt., G. Breddin det., P. Kment revid. ( SDEI); Ceylon, Colombo, 1 J 1 ♀, W. Horn lgt., G. Breddin det., P. Kment revid. ( SDEI); Ceylon, Horton Plain, 1 ♀, W. Horn lgt., G. Breddin det., P. Kment revid. ( SDEI); Ceylon, Nalanda, 1 ♀, W. Horn lgt., G. Breddin det., P. Kment revid. ( SDEI).

Redescription. Colouration. Body above ( Figs 1, 3–5 ) dark brown to black except: antennae with scape (I), basipedicellite (IIa), basal half to two-thirds of distipedicellite (III), and basal one-fourth of basiflagellum (IV) and distiflagellum (V), lateral margins of pronotum, hypocostal lamina ( Fig. 2 ), one small callose spot on each anterolateral angle of scutellum and a very small median callose spot along its anterior margin (spots on anterior margin of scutellum arranged in a line), a small round callose spot on disc of each corium ( Fig. 1 ), and middle portion of each connexival segment, whitish to ochraceous; membrane infuscated, translucent.

Ventral surface ( Figs 2 , 7 ) whitish to ochraceous except mandibular plates laterally, labiomere IV, pro-, meso-, and metasternum, broad median longitudinal spot on abdominal venter, gradually narrowing posteriad, undulated on ventrites V and VI, narrow ring around each spiracular opening, a broken ring on each femur near distal one-fourth, apical half of claws, and anterior and posterolateral angles of connexival segments, black.

Integument, vestiture and structure as in the generic redescription.

Male genitalia ( Figs 16–31 ). Genital capsule ( Figs 16–19 , 22–24 ) slightly longer than wide, subquadrate with posterolateral (= caudal) lobes broad, well-developed, apices of posterolateral lobes arcuately rounded. Dorsal rim ( Figs 16 , 22 : dr) deeply and concavely excavated with narrow median emargination; median emargination concave; infoldings of dorsal rim slightly developed with partially developed parameral sockets. Ventral rim ( Figs 17 , 23 : vr) with narrow rectangular notch as wide as posterolateral lobes; infoldings of ventral rim moderately developed with narrow, short, V-shaped notch medially. Parameres ( Figs 20–21 , 25–27 ) with large bilobed crown, one lobe slightly smaller with apex twisted mesad, other lobe larger, with short, triangular projection directed mesad, stem broad, short. Articulatory apparatus ( Fig. 28 ). Basal plate and support bridge complex, fused to form elongate subtriangular plate-like structure with roughly kidney-shaped capitate process attached through dorsal connectives. Phallus ( Figs 29–31 ). Phallotheca nearly of uniform width in ventral view with base slightly constricted, hinges not well-developed, dorsal wall convex basally, ventral wall concave medially, slightly convex basally. Three conjunctival processes present, dorsal process short, membranous, broadest apically, a pair of ventral conjunctival processes, obovate, bifid apically, each with two broad pigmented stripes dorsally, converging towards apex. Processes of aedeagus absent. Aedeagus elongate, tube-like, longer than ventral conjunctival processes, phallotreme oblique.

Female genitalia ( Figs 32–33 ). Terminalia ( Fig. 33 ). Valvifers VIII rectangular with mesial margins slightly concave medially, inner posterior angles angular, not developed. Valvifers IX nearly trapezoidal. Laterotergites IX elongate subtriangular, each with posterior apex rounded. Laterotergites VIII triangular. Gynatrium ( Figs 32–33 ) with a triangular sclerite surrounding spermathecal opening, ring sclerites absent. Spermatheca ( Fig. 32 ). Proximal spermathecal duct longer than distal spermathecal duct; dilation long, with proximal one-third opaque, twisted upwards basally; distal invagination of spermathecal duct (= sclerotized rod) nearly of uniform width throughout except slightly broader apically; intermediate part of spermatheca short, proximal flange narrower than distal flange; apical receptacle orbicular without ductules ( Fig. 32 : ar).

Measurements (mm). Males (n = 5; median (minimum– maximum)). Body length 8.72 (8.24–9.00); head: length 1.74 (1.63–1.86), width 1.81 (1.76–1.86), interocular width 1.10 (1.01–1.14); lengths of antennomeres: I – 0.49 (0.44–0.54), IIa – 0.74 (0.67–0.81), IIb – 0.65 (0.59–0.76), III – 0.99 (0.92–1.09), IV – 1.07 (1.03–1.16); lengths of labiomeres: I – 0.99 (0.86–1.07), II – 1.55 (1.45–1.65), III – 0.65 (0.58–0.74), IV – 0.67 (0.64–0.70); pronotum: length 1.84 (1.70–1.91), width 4.78 (4.39–5.02); scutellum: length 3.08 (2.81–3.30), width 2.86 (2.48–2.97).

Females (n = 5; for labiomeres n = 4); median (minimum–maximum). Body length 9.41 (8.44–10.29); head: length 1.87 (1.69–1.96), width 1.93 (1.86–2.06), interocular width 1.17 (1.06–1.27); lengths of antennomeres: I – 0.54 (0.45–0.54), IIa – 0.77 (0.73–0.86), IIb – 0.64 (0.60–0.70), III – 1.04 (0.91–1.06), IV – 1.12 (1.08–1.16); length of labiomeres: I – 1.03 (0.94–1.11), II – 1.54 (1.43–1.83), III – 0.62 (0.61–0.67), IV – 0.71 (0.67–0.81); pronotum: length 1.99 (1.91–2.21), width 5.06 (4.70–5.73); scutellum: length 3.29 (3.02–3.48), width 3.22 (2.83–3.68).

Variation. The examined specimens vary in the following characters: Size and shape of the apical notch at the humeral angles, varying from distinct indentation to merely a shallow incision ( Figs 1, 4–5 , 10 ). Whitish callose spot on disc of corium well-developed ( Fig. 1 ) or indistinct ( Fig. 5 ). The specimens also differ in the shade of the brown dorsal colouration, in some specimens with distinct whitish markings on pronotum ( Figs 1, 4 ), scutellum and exocorium, in some specimens the scutellum and exocorium distinctly paler than surrounding surface.

Bionomy. Usually found feeding on small herbs and shrubs in various ecosystems. Concerning plant associations, CHATTERJEE (1934) found the species repeatedly on Santalum album ( Santalaceae ) without further details. MATHUR & SINGH (1960) reported it feeding on sap of Indigofera arrecta ( Fabales : Fabaceae ). According to material we examined it was found feeding on Buddleja asiatica ( Figs 35–36 ) and Scrophularia sp. (both Lamiales : Scrophulariaceae ) especially during September coinciding with the flowering period (feeding plants sensu BURCKHARDT et al. 2014).

Distribution ( Fig. 37 ). South India: Karnataka ( CHATTERJEE 1934), Tamil Nadu ( DISTANT 1900, 1902; CHATTERJEE 1934; CHANDRA 1953); Sri Lanka ( DISTANT 1900, 1902; BREDDIN 1909). For details see Table 1.

Comment on types. DISTANT (1900) described the species Tolumnia immaculata based on an unspecified number of syntypes coming from three different localities and four different collections: Ceylon (E. E. Green – Brit. Mus., G. Lewis – Coll. Dist.); India: Nilgiri Hills (Sir G. F. Hampson – Coll. Dist.), Kotagira (Atkinson Coll. – Brit. Mus.). Despite this fact, ZAIDI (1995) cited the examined material as follows: ‘ Holotype, South India: Nilgiri hills leg Hampson in NHM other materials 1 male, 1 female Srilanka: [sic!] Colombo 29.3. 1929 in the same museum as holotype’. The specimen mentioned as holotype by ZAIDI (1995) is indeed a syntype, but the remaining specimens from Colombo do not belong to the type series. There is no evidence in ZAIDI (1995) that the author intentionally wanted to select the one of the syntypes as the only name bearing type, therefore we consider his action merely an incorrect use of the term holotype and not a valid lectotype designation (see ICZN 1999: Article 74.5). In our opinion all the syntypes we examined are conspecific and there is currently no need for a lectotype designation.

Figures

Figs 5–7. Mormoschema immaculatum (Distant, 1900), stat.restit., syntype from India:Kotagiri. 5 – habitus (dorsal view); 6 – labels; 7 – habitus (ventral view). Scale bars: 1 mm (5, 7). Photo: Salini.

Figs 8–11.Mormoschema immaculatum (Distant, 1900), stat.restit.,Sri Lanka:Nuwara Eliya:8–9 – head (8 – dorsal view, 9–ventralview);10 – head and thorax (dorsal view); 11 – trichobothria on abdominal ventrite VII. Lettering: t – trichobothrium. Scale bars: 1 mm (8–9), 2 mm (10), 200 μm (11). Photo: P. Kment.

Figs 12–15. Mormoschema immaculatum (Distant, 1900), stat. restit., Sri Lanka: Nuwara Eliya: 12 – meso-, metathorax and abdominal ventrite III; 13 – external scent efferent system of the metathoracic scent gland; 14 – detail of peritreme; 15 – detail of metathoracic spiracle with filter processes. Lettering: mc – mesosternal carina, p – peritreme, s – metathoracic spiracle. Scale bars: 1 mm (12–13), 100 μm (14), 50 μm (15). Photo: P. Kment.

Figs 16–21. Mormoschema immaculatum (Distant, 1900), stat. restit., Sri Lanka: Nuwara Eliya, male genitalia: 16–19 – genital capsule (16 – dorsal, 17 –ventral, 18 – caudal, 19 –lateral view); 20–21 – paramere (two different planes). Scale bars: 500 μm (16–19), 300 μm (20–21). Photo: P. Kment.

Figs 1–4. Mormoschema immaculatum (Distant, 1900), stat. restit., India: Karnataka: 1–2 – habitus (1 – dorsal view, 2 –ventral view); 3 – head (dorsal view); 4 – pronotum. Lettering: c – cicatrix. Scale bars: 1 mm (1–2), 0.5 mm (3–4). Photo: Salini.

Figs 22–27. Mormoschema immaculatum (Distant, 1900), stat. restit., India: Karnataka, male genitalia: 22–24 – genital capsule (22 – dorsal, 23 – ventral, 24 – caudal view); 25–27 – paramere (three different planes). Lettering: dr – dorsal rim, pl – posterolateral (= caudal (lobes), vr – ventral rim. Scale bars: 0.2 mm. Photo: Salini.

Figs 28–34. Mormoschema immaculatum (Distant, 1900), stat. restit., India: Karnataka, male and female genitalia, external scent efferent system. 28 – articulatory apparatus; 29–31 – phallus (29 – dorsal, 30 – ventral, 31 – lateral view); 32 – spermatheca attached to ventral side of terminalia; 33 – terminalia (dorsal view); 34 – external scent efferent system. Lettering: ad – aedeagus, ar – apical receptacle, cpd – dorsal conjunctival process, cpv – ventral conjunctival processes, lt8–lt9 – laterotergites VIII or IX, p – peritreme, us – inverted U-shaped sclerite, vlf8–9 – valvifers VIII or IX. Scale bars: 0.1 mm (28–31), 0.5 mm (32–34). Photo: Salini.

Figs 35–36. Mormoschema immaculatum (Distant, 1900), stat. restit.Associated plant, Buddleja asiatica Lour. (Scrophulariaceae). Photo: Salini.

Fig. 37. Distribution map of Mormoschema immaculatum (Distant, 1900), stat. restit.