Triplatyx quadraticeps Horváth, 1904

Kment, Petr, 2008, A revision of the endemic Madagascan genus Triplatyx (Hemiptera: Heteroptera: Pentatomidae), Acta Entomologica Musei Nationalis Pragae 48 (2), pp. 543-582 : 564-570

Triplatyx quadraticeps Horváth, 1904

( Figs. 4-6 , 13 , 17, 22 , 24 , 32 , 44-46 , 50 a-b, 55, 58, 74, 80-81, 86)

Triplatyx quadraticeps Horváth, 1904: 256-257 . Description. Triplatyx quadraticeps: BERGROTH (1908) : 156. Catalogue. Triplatyx quadraticeps: KIRKALDY (1909) : 201. Catalogue. Triplatyx quadraticeps: CACHAN (1952) : 374. Redescription, key.

Type locality. Madagascar, Antongil Bay [= Baie d’Antongila] [15°26′S, 49°45′E for Maroantsetra].

Type material examined. LECTOTYPE: J, ‘ Madagascar / Antongil B. / Mocquerys [p, white label] // Triplatyx / quadraticeps Horv. [hw, white label, quirefold] // J [p, white label] // LECTOTYPUS / TRIPLATYX / QUADRATICEPS / Horváth, 1904 / des. P. KMENT 2008 [p, red label]’ ( HNHM). The lectotype ( Fig. 74 , 80 ) is pinned through the right hemelytron; left protarsus, entire left hind leg, right mid leg (except for coxa and trochanter), and right hind leg (except for coxa) are missing; pygophore is detached, not dissected, mounted on white piece of card attached to the same pin. The lectotype is designated here to fix the species identity in context of the present revision and to avoid later confusion (see ICZN 1999: 74.7.3).

PARALECTOTYPES: 1 J 1 ♀, ‘ Madagascar / Antongil B. / Mocquerys [p, white label] // J resp. ♀ [p, white label] // PARALECTOTYPUS / TRIPLATYX / QUADRATICEPS / Horváth,1904 / des.P.KMENT 2008 [p, red label]’( HNHM). Both paralectotypes are pinned through the right hemelytron ; the male paralectotype with dissected pygophore, one paramere and proctiger mounted on a piece of white card, the aedeagus has unfortunately been lost.

Additional material examined. MADAGASCAR: Périnet [= Andasibe], 8.iii.[1]935, 1 ♀ 1 larva, Olsuf’ev lgt. ( ZMAS).

Redescription. Adult ( Figs. 74 , 80 ). Colouration. Body dorsally brown; head posteriorly, pronotum and scutellum with pale callose median stripe; anterolateral margins of pronotum usually narrowly pale brown. Antennomere 1 brown in basal half, pale brown in distal half; antennomeres 2 and 3 pale brown; antennomeres 4 and 5 dark brown with pale brown bases. Eyes brown. Laterotergites each with small, narrow pale spot medially at their very margin. Ventral surface of body dark brown. Rostrum brownish, apically dark brown. Legs pale brown with irregular brown spots; claws in apical halves black. Abdominal spiracles black.

Sculpture. Body dorsally densely punctate; interspaces among punctures narrower than their diameters, if wider, than forming irregular, pale, convex callosities; punctures brown to dark brown, rarely black. Callosities beige, concentrated in the middle of frons, pronotum, and scutellum (here coalescent into longitudinal pale line), and on anterolateral pronotal margins ( Fig. 80 ). Posterior part of pronotum, sides and apex of scutellum, clavus, and corium all with scattered small irregular callosities. Basal angles of scutellum with small, elevated, globular beige callose grain. Ventral surface of body very densely punctate, punctures on thorax distinctly larger than those on head and abdomen, abdomen medially with much sparser punctation than on sides; thorax with scattered irregular beige callosities, especially on acetabula ( Fig. 17 ). Legs without distinct punctures.

Structure. Head strongly declivous, nearly trapezoid in outline ( Fig. 4 ). Lateral margins in front of eyes with triangular anteocular spine, more anteriorly lacking distinct incision; paraclypei foliaceous, flattened, long and wide, from anteocular spine on obliquely widening laterad, anteriorly regularly arcuate mesad with anterior margin nearly straight; paraclypei meeting in front of clypeus, forming minute, hardly distinct triangular incision; surface of paraclypei slightly depressed medially in front of eye and slightly raised anterolaterally; anterior margin both dorsally and ventrally without setae. Clypeus and frons very slightly convex. Antennomeres ordered from shortest to longest as 3 ≤ 1 ≤ 2 ≤ 4 <5. Bucculae regularly narrowing anteriad, evanescent, posteriorly slightly narrowed and rounded apically, lower margin slightly insinuated medially ( Fig. 5 ). Rostrum with apex reaching between metacoxae.

Pronotum ( Fig. 13 ). Anterolateral angles truncated, laterally with distinct spine; anterolateral margins concave, carinate, bearing one short triangular spine medially and one additional spine laterally near humeral angles. Humeral angles wide, distinctly produced anteriad, slightly declivous, widely rounded, laterally with 5-6 small, more or less lobe-like projections; the most posterior projection usually slightly protruding from arcuate outline of pronotum; margins of pronotum behind humeral angles slightly convex, regularly narrowing towards scutellum; posterior margin slightly concave. Disc anteriorly and medially nearly flat, obliquely descending towards head, without any elevation; dorsal surface of humeral angles confluent with rest of pronotum, only slightly concave basally; posterior part of pronotum distinctly convex sublaterally, slightly convex to nearly flat medially, confluent with anterior surface of scutellum or pronotum and scutellum forming very obtuse angle ( Fig. 74 ).

Scutellum. Basal angles shallowly depressed; scutellar disc elevated, forming high, round hump ( Fig. 74 ), occupying anterior two-thirds of scutellum with anterior surface convex, more or less confluent with pronotum; sides of scutellum slightly concave in midlength, posteriorly rounded and regularly declining towards apex, lacking any elevation; scutellar apex wide, nearly flat.

Hemelytra. Clavus with 3-4 irregular rows of punctures in widest place; apex of membrane not surpassing apex of abdomen ( Fig. 80 ).

Thorax ventrally flattened; sternum between coxae deeply furrowed. Ostiole situated on small tubercle, round, slanted ventrolaterad, accompanied with very small auricle ( Fig. 17 ); auricle about as long as ostiole wide; metapleuron around ostiole hardly depressed. Evaporatorium small, developed both on meso- and metapleuron; on mesopleuron, evaporatorium forming only narrow strip along posterior margin and widened in its posterolateral angle; on metapleuron, evaporatorium surrounding tubercle bearing ostiole and projecting as narrow strip mesad between meso- and metacoxae, and laterad on anterior margin along thoracic spiracle and further laterad, forming distinct ‘outlet channel’ ( Figs. 17 , 24 ); gyrification poorly developed.

Legs. Protibiae hardly widening towards apex, their outer surface distinctly flattened, lateral margins carinated.

Abdomen only slightly narrower than pronotum across humeral angles; sternite III not depressed anteromedially. Laterotergites fully exposed dorsally, mediotergites completely covered with hemelytra; laterotergite III laterally distinctly bisinuate, with more or less protruding projection medially; laterotergites IV-VI slightly bisinuate laterally, laterotergites VII-VIII laterally straight ( Fig. 32 ); dorsal surface of laterotergites nearly flat, sometimes with shallow depressions medially.

Male genitalia. Pygophore ( Figs. 44-46 ) relatively small (pygophore width 0.88-0.90 mm, ratio pygophore width to body length 0.15; n = 2); ventral wall gibbose; ventral rim obscured, indicated only medially as short, hardly raised and obtuse ridge; ventral wall continually merging into ventral rim infolding, both deeply depressed subapically at base of posterolateral angles, the depression sharply delimiting the posterolateral angles; ventral rim infolding bent dorsally, shallowly concave medially, lateral projections nearly rectangular ( Fig. 45 ); posterolateral angles more widely rounded laterally, lateral rim of posterolateral angles narrower; lateral rim infolding dorsally with tooth-shaped projection ( Fig. 45 , red arrow); paramere sockets distinct; apices of parameres visible, curved, directed dorsolaterad. Paramere simple, laterally flattened, apical portion slightly longer than basal portion, medially curved, crescentshaped, apically narrowly rounded ( Fig. 50 ); apex of paramere in dorsal view slightly widened and flattened. Phallotheca of aedeagus nearly parallel-sided basally, slightly oval apically, sclerotized apical processes of median penal plates narrow, well developed ( Fig. 55 ).

Female genitalia ( Fig. 58). Gonocoxites 8 with posterior margin slightly concave and sutural margin convex; both gonocoxites 8 almost in contact medially; gonapophyses 9 visible; posterior margin of laterotergites 9 narrowly rounded. Internal female genitalia not examined.

Measurements (all in mm). See also Table 1. The lectotype (J): body length 6.0; head: length 1.65, width 2.1, interocular width 1.55; length of antennomeres: 1 – 0.35-0.4, 2 – 0.35- 0.4, 3 – 0.3-0.35, 4 – 0.4-0.45, 5 – 0.6-0.65; pronotum: length 1.6, width 5.1; scutellum: length 2.55, width 2.7; abdomen width 4.95 mm. Females larger than males: JJ 6.0 mm, ♀♀ 6.3-7.1 mm.

Larva (instar 5) ( Fig. 81 ). Generally similar to adults in shape and colouration.

Colouration. Body brown, anterolateral margins of pronotum, sides of wing pads,, and most of abdominal dorsum and venter pale brown. Apical antennomeres, ostioles of dorsoabdominal scent glands and abdominal spiracles black; tarsal claws pale brown.

Sculpture. Body with both dorsal and ventral surfaces densely covered with concolorous to brown punctures; legs covered with shallow concolorous punctures. No callosities developed.

Structure. Head ( Fig. 6 ) nearly quadrangular, paraclypei less widening laterad, anterolaterally more rounded, with distinct medial triangular incision at tip of clypeus. Pedicel undivided, length of antennomeres ordered from shortest to longest as 1 <4 <5 <(2+3). Pronotum with posterior margin straight. Scutellum distinctly shorter than wide basally; disc elevated, forming a hump. Fore wing pads as long as, and covering most of, hind wing pads, anteriorly with triangular projection on lateral margin. Abdominal tergum with paired ostioles of all three dorso-abdominal scent glands.

Measurements in Table 1.

Variability. All four specimens examined differ slightly in the intensity of dark colouration of ventral surfaces of head and thorax, the density of black punctures on body, and the convexity of posterior margin of pronotum; there are prominent differences in the shape of humeral angles of pronotum, which can differ even between both sides of a same specimen.

Differential diagnosis. Triplatyx quadraticeps is habitually very similar to T. dubius and T. kerzhneri sp. nov. (see the comments under T. dubius ). Triplatyx quadraticeps is characterized by the following genitalic characters: posterolateral angles of pygophore laterally rounded ( Figs. 44-45 ); ventral wall of pygophore continually merging into ventral rim infolding, both deeply depressed subapically at base of posterolateral angles, the depression sharply delimiting the posterolateral angles; lateral rim of posterolateral angles narrower; lateral rim infolding dorsally with tooth-shaped projection ( Fig. 45 , red arrow); paramere as in Fig. 50 . Triplatyx quadraticeps has also a well developed scutellar hump, a pale callose midline on pronotum and scutellum, more prominent humeral angles of pronotum, and a very small auricle (approximately as long as ostiole wide) ( Fig. 22 ).

Collecting notes. The female and larva from Périnet were collected in March.

Distribution. Both known localities are situated in eastern Madagascar in drainage areas of rivers flowing eastwards to the Indian Ocean, grown with humid forests.

Figures

Figs. 1-7. Head (1-4, 6-7 – dorsal view, 5 – lateral view). 1 – Triplatyx bilobatus Cachan, 1952 (J, Isalo NP); 2 – T. dubius Jensen-Haarup, 1931 (J, Ankarafantsika forest); 3 – T. kerzhneri sp. nov. (J, holotype, Maromandia); 4-6 – T. quadraticeps Horváth, 1904 (4-5 – J, lectotype, Antongil Bay; 6 – larva, Périnet); 7 – T. stysi sp. nov. (J, holotype, Ranomafana NP). Scale bar = 1 mm.

Figs. 8-14. Pronotum. 8 – Triplatyx bilobatus Cachan, 1952 (J, Isalo NP); 9-11 – T. dubius Jensen-Haarup, 1931 (9 – ♀, Anjahantelo; 10 – J, Ankarafantsika forest; 11 – J, ‘Madag’); 12 – T. kerzhneri sp. nov. (J, holotype, Maromandia); 13 – T. quadraticeps Horváth, 1904 (J, lectotype, Antongil Bay); 14 – T. stysi sp. nov. (J, holotype, Ranomafana NP). Scale bar = 1 mm.

Figs. 15-23. 15-18 – meso- and metapleuron (magnfication 63×); 19-23 – metathoracic scent gland auricle (90×). 15, 19 – Triplatyx bilobatus Cachan, 1952 (J, Isalo NP); 16, 20 – T. dubius Jensen-Haarup, 1931 (J, Lambomakandro); 21 – T. kerzhneri sp. nov. (J, holotype, Maromandia); 17, 22 – T. quadraticeps Horváth, 1904 (J, lectotype, Antongil Bay); 18, 23 – T. stysi sp. nov. (♀, paratype, Moramanga). Photo: P. Kment.

Figs. 24-28.24-27 – meso- and metapleuron. 24 – Triplatyx quadraticeps Horváth, 1904 (J, lectotype,Antongil Bay); 25 – T. stysi sp. nov. (♀, paratype, Moramanga); 26 – Anoano pronotalis Cachan, 1952 (J, syntype, Ambovombe, MNHN); 27 – Tricompastes gigas Cachan, 1952 (♀, no locality, MNHN). 28 – abdominal dorsum of T. dubius Jensen-Haarup, 1931 (♀, Madagascar, Fairmaire). Scale bars = 1 mm; evaporatorium grey.

Figs. 29-34. Connexivum. 29 – Triplatyx bilobatus Cachan, 1952 (J, Isalo NP); 30-31 – T. dubius Jensen-Haarup, 1931 (30 – ♀, Anjahantelo; 31 – J, Ankarafantsika forest); 32 – T. quadraticeps Horváth, 1904 (J, lectotype, Antongil Bay); 33-34 – T. stysi sp. nov. (33 – J, holotype, Ranomafana NP; 34 – ♀, paratype, Moramanga). Scale bar = 1 mm.

Figs. 41-46. Pygophore (41-42, 44-45 – posterodorsal view, ventral rim above; 42, 45 – dissected; 43, 46 – ventral view). 41-43 – T. dubius Jensen-Haarup, 1931 (‘Madag’; width 0.78 mm); 44-46 – T. quadraticeps Horváth, 1904 (paralectotype, Antongil Bay; width 0.88 mm). Photo: J. Macek (41, 43-44, 46) & P. Kment (42, 45).

Figs.47-51. Paramere, lateral view. 47 – Triplatyx bilobatus Cachan, 1952 (Isalo NP); 48 – T.dubius Jensen-Haarup, 1931 (‘Madag’); 49 – T. kerzhneri sp. nov. (J, holotype, Maromandia); 50a-b – T. quadraticeps Horváth, 1904 (two different views – paralectotype, Antongil Bay); 51 – T. stysi sp. nov. (paratype, Ambodinifody env.). Scale bar = 0.5 mm.

Figs. 71-75. Habitus of Triplatyx species, lateral view. 71 – Triplatyx bilobatus Cachan, 1952 (J, Isalo NP); 72 – T. dubius Jensen-Haarup, 1931 (♀, Zombitsy NP); 73 – T. kerzhneri sp. nov. (J, holotype, Maromandia); 74 – T. quadraticeps Horváth, 1904 (J, lectotype, Antongil Bay); 75 – T. stysi sp. nov. (J, holotype, Ranomafana NP). Photo: J. Macek.

Figs. 80-83. Habitus of Triplatyx species. 80-81 – T. quadraticeps Horváth, 1904: 80 – J, lectotype, Antongil Bay; 81 – larva, Périnet. 82-83 – T. stysi sp. nov.: 82 – J, holotype, Ranomafana NP; 83 – ♀, paratype, Moramanga. Photo: J. Macek (80, 82) & P. Kment (81, 83).

Figs. 52-56. Phallus. 52a-c – Triplatyx dubius Jensen-Haarup, 1931 (a – dorsal view, b – lateral view, c – ventral view; a,c – ‘Madag’, b – Lambomakandro); 53a-b – T. bilobatus Cachan, 1952 (a – dorsal view, b – ventral view; Isalo NP); 54 – T. kerzhneri sp. nov. (dorsal view; holotype, Maromandia); 55 – T. quadraticeps Horváth, 1904 (dorsal view; paralectotype, Antongil Bay); 56 – T. stysi sp. nov. (dorsal view; paratype, Ambodinifody env.). Scale bar = 0.5 mm; abbreviations: aa – articulatory apparatus, apr – apical process of median plate, cj – conjunctiva, dsp – ductus seminalis proximalis, er – ejaculatory reservoir, pht – phallotheca, sg – secondary gonopore, ve – vesica.