Triplatyx 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 : 547-549

Triplatyx Horváth, 1904

( Figs. 1-25, 28 -86)

Triplatyx Horváth, 1904: 255-256 . Type species: Triplatyx quadraticeps Horváth, 1904 , by monotypy. Triplatyx: BERGROTH (1908) : 156. Catalogue. Triplatyx: KIRKALDY (1909) : 201. Catalogue. Triplatyx: CACHAN (1952) : 373 -374. Diagnosis, key.

Redescription. Colouration and sculpture. Basic colouration pale to dark brown, antennae and legs usually paler. Body densely and coarsely punctate, here and there with irregularly distributed small impunctate callosities between punctures; on pronotum and scutellum, callosities sometimes merging into longitudinal callose line.

Structure. Body markedly convex dorsally, convex to nearly flat ventrally. Small species, females slightly larger than males; body length: JJ 4.7-6.8 mm, ♀♀ 5.4-7.5 mm.

Head ( Figs. 1-7 ) declivous, shorter than wide across eyes, nearly quadrangular to trapezoidal in outline (anteriorly wider than posteriorly), behind eyes convex, laterally rounded; posterior margin nearly straight in middle, sunken into pronotum. Lateral sides in front of eyes deeply ( Fig. 1 ) to slightly ( Fig. 3 ) sinuate and bearing distinct triangular anteocular spine; paraclypei foliaceous, slightly depressed medially to nearly flat, long and wide, meeting in front of clypeus, regularly rounded laterally and anteriorly with small angle between both paraclypei against tip of clypeus, or with straight sides, widening anteriad, then shortly and strongly arcuate mesad with anterior margin nearly straight. Clypeus slender, narrowing and closed anteriorly, slightly convex to nearly flat. Frons usually only slightly convex. Eyes small, protruding by ca. half of their width from outline of head; temples behind eyes narrowing laterad, not surpassing eye laterally. Ocelli small, situated posteriorly and medially behind eyes near posterior margin of head, but remote from anterior margin of pronotum. Antenniferes small, not visible from above ( Fig. 5 ). Antennae slender, antennomeres ranked from shortest to longest usually as 1 ≤ 3 ≤ 2 <4 <5; antennomere 1 cylindrical, shortest, as stout as or slightly more slender than antennomere 5; antennomere 2 cylindrical, most slender of all; antennomere 3 cylindrical, slightly thickening towards apex; antennomeres 4 and 5 spindel-shaped, antennomere 4 stouter than 3, antennomere 5 stoutest; apex of antennomere 2 and entire antennomere 3 with sparse, and antennomeres 4 and 5 with dense pale semierect setae. Bucculae ( Fig. 5 ) long and low, lower margin straight or slightly insinuated medially, regularly narrowing anteriad and evanescent (only in T. bilobatus not narrowing, anteriorly rectangular), posteriorly nearly rectangular. Rostral segment 1 not higher and distinctly shorter than bucculae, not surpassing their posterior margin; apex of rostrum reaching anterior margins of metacoxae or situated between them ( Fig. 68 ).

Pronotum ( Figs. 8-14 , 70 , 78 ) about three-times wider than long; anterior margin deeply emarginated with sides rounded laterally and, nearly straight medially; anterolateral angles truncated, usually with distinct lateral spine; anterolateral margins slightly to deeply concave, usually carinate, with one or more spines; humeral angles large, markedly produced laterad and more or less distinctly anteriad and dorsad, laterally widely arcuate to truncate with margin sinuate to spinose; sides of pronotum behind humeral angles arcuate to nearly straight, narrowing towards scutellum; posterior margin of pronotum straight to slightly concave in middle. Disc nearly flat in middle, anteriorly with more or less developed elevation and/or impunctate median ridge ( Figs. 8-14 ); posterior part more or less convex.

Scutellum approximately triangular, as long as wide; basal angles shallowly depressed, with small callose grain usually present anteriorly near inner margin of each depression; lateral margin insinuated near midlength; apex widely rounded, not reaching posterolateral angles of corium. Disc strongly convex, often forming a hump ( Figs. 64-66 , 71-75 ), regularly declivous towards margins, apex in some species flat; median longitudinal ridge developed or absent.

Hemelytra. Clavus narrow, with 3-5 more or less regular rows of punctures in the widest place (e.g., Fig. 69 ), strongly narrowing posteriad (with only one row of punctures), reaching insinuation near midlength of scutellum. Sides of corium nearly parallel basally, slightly divergent more apically; corium widest approximately in anterior third and then arcuately narrowed posteriad ( Figs. 29-34 ); posterolateral corial angle widely rounded, slightly surpassing apex of scutellum. Membrane translucent, widely rounded posteriorly, almost reaching apex of abdomen.

Thorax with venter convex to rather flattened; sternum between coxae shallowly to deeply furrowed ( Figs. 68 , 83 ). Ostiole of metathoracic scent gland shifted laterad, situated sligthly interior of half-width (0.42-0.47) of metapleuron ( Figs. 15-18 , 24-25 ), issuing on small to large tubercle, round, orthogonal and directed laterad ( Fig. 19, 23 ) to oblique and directed ventrolaterad ( Figs. 20-22 ), accompanied with one small to very small auricle ( Figs. 19-23 ). Evaporatorium developed both on meso- and metapleuron, on mesopleuron large ( T. stysi sp. nov., Fig. 25 ) or small, present only as narrow strip on posterior margin along thoracic spiracle and slightly wider in posterolateral angle of mesopleuron ( Figs. 16-17 , 24 ); metapleural evaporatorium surrounding the tubercle bearing ostiole and projecting as narrow strip mesad between meso- and metacoxae, and laterad on anterior margin of metapleuron along thoracic spiracle; gyrification developed. Posterior margin of mesopleuron and anterior margin of metapleuron depressed along thoracic spiracle and further laterad (including the posterolateral angle of mesopleuron), bearing evaporative microsculpture and forming thus an ‘outlet channel’ leading up to lateral margin of thorax. Posterolateral angle of metapleuron separated by deep and wide furrow.

Legs. Femora stouter and distinctly longer than tibiae ( Figs. 68 , 83 ), oval in cross-section; profemora stoutest, spindel-shaped, narrowing towards base and apex; meso- and metafemora slightly widening towards apex, widest subapically. Tibiae with outer surface flattened; protibiae stoutest, metatibiae most slender. Tarsomere 2 shortest, tarsomere 3 longest, about as long as tarsomeres 1 and 2 together.

Abdomen slightly wider to slightly narrower than pronotum across humeral angles. Abdominal dorsum with distinct pair of guttiform scars of ostioles of anterior dorso-abdominal scent gland between tergites III and IV ( Fig. 28 ; examined in females of T. dubius ). Connexivum wide, fully exposed dorsally; outer margin of laterotergites very slightly to distinctly sinuate ( Figs. 29-34 ). Abdominal venter slightly convex, medially nearly flat, slightly concave near margin; ventrite III not depressed medially (except for T. stysi sp. nov.) ( Figs. 68 , 83 ); spiracle on ventrite II covered by metapleuron.

Male genitalia. Pygophore small (ratio of pygophore width to body length equal to 0.13- 0.19), in ventral view, trapezoidal with lateral margins slightly arcuate ( Figs. 36, 38, 40 , 43, 46 ); ventral wall large and gibbose; ventral rim well developed ( Fig. 36 ) or obscured, then merging with ventral rim infolding ( Fig. 38 ); ventral rim infolding usually bent upwards, medially shallowly concave to deeply incised, laterally produced into triangular projections (e.g., Figs. 38 , 42, 45 ); cup-like sclerite well developed; dorsal wall narrow, dorsal rim hardly developed; dorsal and lateral rim infoldings well developed; genital chamber opening directed posterodorsally; paramere sockets shallow ( Figs. 42, 45 ); apical parts of parameres usually visible (not in T. stysi sp. nov.); posterolateral angles ear-like, rounded, only slightly surpassing ventral rim posteriorly. Paramere simple, laterally flattened, L- to crescent-shaped ( Figs. 47-51 ). Phallotheca of aedeagus nearly parallel-sided ( Figs. 55-56 ) to oval ( Fig. 53 ), widely opened dorsally, without processes; vesica tubular, narrow, usually accompanied with sclerotized apical processes of median penal plates (indistinct in T. kerzhneri sp. nov.) (e.g., Fig. 52 ).

Female genitalia. External female genitalia ( Figs. 57-59) with gonocoxites 8 nearly touching medially or widely apart, with posterior margin slightly concave and sutural margin slightly convex; gonapophyses 8 visible; posterior margin of laterotergites 9 narrowly rounded. Internal female genitalia examined only in T. dubius (see Figs. 60-63).Apical receptacle of spermatheca generally sphaerical, pigmented, lacking basal neck-like duct, apically with bunch of several curved and branched processes of variable shape ( Figs. 61-63); intermediate part with both distal and proximal flange well developed, desclerotized and non-pigmented flexible zone situated near distal flange; spermathecal duct with short distal part, followed by large and elongated dilatation, about twice as long as apical receptacle and intermediate part together ( Fig. 60); proximal part of spermathecal duct longer than distal part. Ring sclerites (= chitinellipsen) of parietovaginal glands present, rather small, guttiform, laterally rounded, medially pointed; anterior thickenings of vaginal intima forming V-shaped structure ( Fig. 57, 60).

Differential diagnosis. The genus Triplatyx is easily distinguished from both Anoano and Tricompastes by the characters given in the key (see above).

Etymology. HORVÁTH (1904) established this generic name without any information concerning its etymology and gender. JENSEN- HAARUP (1931) combined Triplatyx with species epithet dubius , considering thus Triplatyx as masculine.

Distribution. Madagascar (Fig. 86).

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. 67-70. Habitus of Triplatyx bilobatus Cachan, 1952. 67-68 – J, Isalo NP (67 – dorsal view, 68 – ventral view); 69-70 – J, holotype, Ambovombe (69 – dorsal view, 70 – detail of head and pronotum). Photo: J. Macek (67) & P. Kment (68-70).

Figs. 76-79. Habitus of Triplatyx species. 76-78 – Triplatyx dubius Jensen-Haarup, 1931: 76 – ♀, Zombitsy NP; 77- 78 – ♀, holotype, Madagascar, coll. Sicora. 79 – T. kerzhneri sp. nov.: J, holotype, Maromandia. Photo: J. Macek (76, 79) & P. Kment (77-78).

Figs. 64-66. Habitus of Triplatyx dubius Jensen-Haarup, 1931, lateral view. 64 – ♀, Anjahantelo; 65 – J, Ankarafantsika forest; 66 – J, ‘Madag’. Scale bar = 1 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. 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. 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. 35-40. Pygophore (35, 37 – posterodorsal view, ventral rim above; 36, 38, 40 – ventral view; 39 – posterior view, dissected). 35-36 – Triplatyx bilobatus Cachan, 1952 (Isalo NP; width 0.90 mm); 37-38 – T. kerzhneri sp. nov. (holotype, Maromandia; width 1.05 mm); 39-40 – T. stysi sp. nov. (paratype, Ambodinifody env.; width 1.05 mm). Photo: J. Macek (35-38, 40) & P. Kment (39).

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. 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.