Pygoplatys tenangau, Magnien & Smets & Pluot-Sigwalt & Constant, 2008

Magnien, Philippe, Smets, Koen, Pluot-Sigwalt, Dominique & Constant, Jérôme, 2008, A new species of Pygoplatys Dallas (Heteroptera, Tessaratomidae) from the Damar agroforests in Sumatra: description, immatures and biology, Nouvelle Revue d’Entomologie 24, No. 2, pp. 99-112 : 101-108

Pygoplatys tenangau n. sp.

HOLOTYPE Ö, Sumatra, Lampung, Krui, Pahmungan, Damar Garden , 2 -X-2001 K. Smets leg. ( MZBC) .

Paratypes: 132 specimens from: “ Sumatra, Lampung, Krui, K. Smels leg. in the following Institutions as follow :

l Õ, 3 QQ, Pahmungan, Damar garden , I-VII to 15 -VII-2001 ( ISNB) ; 1 å, id. ( MNHN) ; l Q, Penengahan, Damar garden 14-VII-2001 ( MNHN) ; l (Ê, Rata Agung, coffee garden , 18-VII-2001, on Shorea javaníca ( MZBC) ; 1 Q, Pahmungan, Damar garden , 4 -Vlll-2001 ( ISNB) ; l å, id. ( MNHN) ; l Q, id., 0 n Shoreajavanica ( MZBC) ; l Q, same locality, lo-Vlll- 2001, 0n Lancium domesticum ( MZBC) ; 1 Q, id., on Cojfea sp. ( MZBC) ; 1 Q, same locality, Damar garden , 11 -VIII-2001 ( MZBC) ; 1 Q, same Iocality, 12-VIII-2001, on Lancium domestícum ( ISNB) ; 1 Q, id., on Pterospermum sp. ( MZBC) ; 1 Q, id., on Artocarpus domestícus ( MZBC) ; 2 Q, same locality, 13 -Vlll-2001, on Pterospermum sp. ( ISNB) ; 1 Q, id., dead on ground ( MZBC) ; 1 Q, same locality, 14-Vlll-2001, on Perícampylus sp. ( MZBC) ; 1 Q, same locality, 15 - VIII-2001 ( MZBC) ; 1 (î, same locality, 20- VIII-2001, on Shorea javaníca ( MZBC) ; 1 Q, same locality, 23 -VIII-2001, on Pterospermum sp. ( ISNB) ; l Õ, same locality, 25 -VIII-2001, on Shorea javaníca ( MZBC) ; 1 Q, same locality, 2 -IX- 2001 ( MZBC) ; 1 Q, same locality, 3 -IX- 2001, on Leea indica ( MZBC) ; 1 Q, same locality, 4-IX-2001 ( MZBC) ; 1 Q, id., on Citrus sp. ( MZBC) ; 1 å, id., dead on ground ( MZBC) ; 2 QQ, same locality, 5 - IX-2001 ( ISNB) ; 1 Q, id., on Coflea sp. ( MZBC) ; 1 Q, id., on Vítexpinnata ( MZBC) ; 1 Q, id., on Homalorithus populneus ( MZBC) ; 1 Q, id., on Plerospermum sp. ( MZBC) ; 1 Q, id., on Leea indica ( MZBC) ; 2 QQ, same locality, 6 -IX-2001 ( ISNB) ; I Q, id., on Pterospermum sp. ( MZBC) ; 1 Q, same locality, 9- IX-2001, on Pterospermum sp. ( MZBC) ; 1 Q, same locality, 18 -IX-2001, 0n Shorea javanica ( ISNB) ; 1 å, same locality, 20- 1X- 2001 ( MZBC) ; 1 å, id., on grass ( MZBC) ; 1 å, id., on Piper sp. ( MZBC) ; 1 å, id., on Eryzhrina sp. ( MZBC) ; 1 å, 1 Q, same locality, 23 - lx-2001 ( ISNB) ; 1 Q, id., on Shorea javanica ( MZBC) ; 1 Q, same locality, 26- IX-2001 ( MZBC) ; 1 å, 1 Q, same 1ocality, 27 -IX-2001 ( ISNB) ; 1 Q, id., on Píthecellobium clypearía ( MZBC) ; 3 33, 1 Q, same locality, 29- IX-2001 ( MZBC) ; 2 QQ, same locality, 30 - lx-2001 ( ISNB) ; 1 å, same locality, 1 -X-2001 ( MZBC) ; 2 ÕÕ, 1 Q, id., on Shoreajavaníca ( ISNB) , 1 å, id., on Pterospermum sp. ( MNHN) ; 12 åå, 6 QQ, same locality, 2 -X-2001 ( ISNB) ; 2 åå, 2 QQ, same locality, 2 -X-2001 ( MZBC) ; 1 å, 1 Q, id. ( RMNH) ; 1 g?, 1 Q, id. ( NHRS) ; 1 6,1 Q, id. ( RMBR) ; 1 Q, id. ( MNHN) ; 1 3,1 Q, id. ( CWS) , 1 å, 1 Q, id. ( DAR) ; 2 åå, 2 QQ, id. ( PHM) ; l å, 1 Q, same locality, 4 -X-2001 ( ISNB) ; 1 å, id., bred from nymph ( MZBC) ; 1 å, Rata Agung, Coffee-Damar garden 7 -X- 2001, on Coflea sp. ( MZBC) ; 2 åå, 1 Q, id., on Shoreajavaníca ( ISNB) ; 1 3, Sukamarga, Coffee-Damar garden 31 -X-2001, on Shoreajavanica ( MZBC) ; 1 Q, id. ( MNHN) ; 1 Q, same locality, 2 -X 1 -2001 ( MZBC) ; 3 33, l Q, id., on Shoreajavanica ( ISNB) ; 1 å, Pahmungan, Damar garden , 5 -XI-2001, dead ( MZBC) ; 1 å, 1 Q, same 1ocality, 8-XI-2001 ( MZBC) ; 2 33, 2 QQ, same locality, on Shoreajavanica, 11 -X1 - 2001 ( ISNB) ; 3 QQ, same locality, 13 -XI-2001 ( ISNB) ; l Q, same locality, 14-XI-2001 ( MZBC) ; 2 QQ, Ngaras, Damar garden , 15 -XI-2001 ( MZBC) ; 1 å, 1 Q, Way Jambu, Damar garden , 18-XI-2001 ( ISNB) ; l Q, Pahmungan, Damar garden 19-XI-2001 ( MZBC) ; 2 Q Q, id., on Shoreajavanica ( ISNB) .

Other paratypes: 1 å, Borneo [no other indication] ( ISNB) ; 1 å, 1 Q, Sumatra, Lampung Krui, Pahmungan, 24-VII- 1987, on Shorea javanica, A. C. Messer leg. ( BMNH) ; 1 Q, Sumatra Atjeh G. Gurah., 22- Ill- 1954, A. H. G. Alston B. M. 1954-414 .

Other material examined: about 40 specimens of the same localities deposited in MNHN, MZBC and PHM were not designated as paratypes because of immaturity or difformities.

Description.- Habitus: see Plate I, A, B.

Dorsum light chocolate brown. Head paler on clypeus and at the apices of jugae. Pronotum shiny, with metallic greenish ponctuation in vivo, and tranverse paler ochraceous stripe just behind calli, extending onto anterior margin of humeral processi and reaching their apices. Hemelytra of the same hue, somewhat paler, matte. Laterotergites and 8m tergite of the background color, with dark tinges on the margins. Tergites 2 to 7 velvet like purplish red, smooth and shiny in the middle.

Underside reddish-ochraceous to brick rose, of paler hue than dorsum, shiny. Coxae and legs of the same coloration. Stigmates black.

Head. Juga concave, apices rounded surpassing widely the apex of clypeus; clypeus completely enclosed; first article of antennae almost reaching the apices of jugae, articles H and III cylindrical and subequal in length, last article fusiform and somewhat longer than II and 111. Pilosity dense, hairs short. Rostrum short, slightly surpassing the anterior coxae.

Pronotum. Humeral processi exceeding well beyond the abdomen width, margins almost parallel, slightly projected forwards, apex obliquely truncated. Width of pronotum, including humeral processi, on average slightly more than 73 % (min: 68 %, max 82 %) of the habitus length in the male, equal to 73 % (min: 67 %, max 78 %) in the female; anterior calli clearly marked; anterior margins serrulate; disk punctation strong and irregular.. Scutellum: punctation as on pronotum, triangular with apex grooved and lanceolate. Hemelytra: punctation fine and regular; membrane with five or six basal cells, nervures parallel. Stemal process long, apex blunt. reaching base of head in ventral view. Stemum punctation sparse, very coarse on prostemum. Ventral apex of each meso- and metafemur with spines on both sides of tibiae insertion; tibiae pilosity dense and short; segment I of tarsi inflated, with brush of adhesive hairs on the ventral surface, segments ll and III cylindroconical, ll two times shorter than the III.

Abdomen: apex of abdomen rounded in the male, toothed with apices of 7 m 8m and 9m segments almost in line for female. Punctation on stemites fine and concolorous, coarse and blackened on lateral margins.

Genitalia. Õ. Pygophore ( Fig. 6) widening posteriorly, posterior edge polygonal, with a small V-shaped notch medially; opening with a tooth at the interior margin just in front of the sensorial lobe of the paramere. Parameres ( Fig. 4-5) shaped in triangular blade, regularly curved insidewards, sensorial lobe relatively small, with very long setae. Phallosoma (Fig. l) with sclerotized lateral hook-shaped plates on each side; conjunctiva with two pairs of processes: a sclerotized pair in antero-ventral position, stylet shark tooth-shaped ( Fig. 3), and a membranous pair in posterodorsal position, as is the rule in the genus. Vesica very long, ejaculatory chamber strongly curved at base, S-shaped in the middle, strongly tapering at the apex. S? External genitalia as in Fig. 15. Ring sclerites obsolete or absent. Spermatheca ( Fig. 13): apical receptacle ovoid connected to the intermediate part (pumping region) by a long distinctly curved tubular neck; intermediate part with proximal and distal flanges; spermathecal duct bipartite: the posterior part wide and folded, somewhat narrowed near the posterior third; the anterior part long and thin, longer than the posterior part.

Measurements [mean (min-max)]: male: length 22,2 mm (l9,0-24,0), width including humeral processi 16,2 mm (l 3,0- l8,7); female: length 25,2 mm (2 l, 8-27,6), width including humeral processi = 18,4 mm (l 5,3-20,2).

Derivatio nominis. From the local ‘ ” given by the damar farmers in the Krui name tenangau area to the true bugs having a negative impact on the resin production.

Immatures.- The first- through fifth-instar nymphs of P. terzangau sp. are here illustrated ( Fig. 16) from specimens preserved in alcohol. Nymphs are very flat in all instars. Body oval in the first and second instar, almost rectangular in the following instars. General coloration: beige to light brown, dorsally and ventrally; only the third- and fourth-instars brightly colored on the dorsal surface of abdomen and thorax: red or deep pink, with White and black pattern ( Plate I, C). Outer margin of thorax and abdomen serrated and bordered by a thin dark pigmented strip in all instars. Identations of the outer margin formed by small tubercles bearing very minute setae ( Fig. 16 D). Same type of setae on tubercles scattered throughout the body. Lateral part of the thorax, laterotergites and laterosternites unpigmented, hyaline. Marginal “plates” connexivum in the on form of semicircular areas well delimited, usually transparent to translucent, never pigmented. Dorsal scent gland opening between terga III-IV, IV-V, V-VI; distinctly prominent in the median and posterior glands.

Host plant.- Until now, Shorea javarzica Koorders & Valeton ( Dipterocarpaceae ) is the only known host plant allowing the full life cycle of the new species. On only three occasions, adults of P. tenangau n. sp. were seen feeding on other plants: Perícampylus sp. ( Menispermaceae : atypical feeding on the upper side of an old leaf), Pterospermum javanícum ( Sterculíaceae : female guarding eggs) and Vitex pinnata ( Verbenaceae : trapped female with phoretic nymphs).

Distribution. P. tenangau n. sp. is known with certainty only from Sumatra and Bomeo. Apart from the only male specimen from Borneo and one female from Aceh Province, all specimens mentioned in this paper originate from the Krui region, encompassing the whole Pesisir area, from Rata Agung near the Province of Bengkulu in the north, to Sukamarga in the south. Therefore the distribution seems to include at least the entire west coast of Sumatra and an undetermined region of Borneo.

The presence of P. tenangau n. sp., suspected from Peninsular Malaysia and North Borneo (Sarawak), needs confirmation, as old female specimens from these localities preserved in several institutions (BMNI-l, MNHN, RMNH, ISNB) could not be formally identified.

Biological observations. Adults and nymphs of different instars have been seen feeding on young shoots and leaves of damar ( Shorea javanica ) trees. The feeding occurs usually on the midribs and leaf stalks of very young (still folded and hanging) leaves and shoots, While the bugs sit on the underside of the leaf or on the twig. It could be observed on young damar trees from about one to five meters high. We did not attempt observations higher up in the canopy, but during sudden gusts of wind, many nymphs fell from the canopy of damar trees, suggesting they also feed on large trees. Feeding was observed continuously during the whole of the observation period (i. e. from July to November 2001).

Mating usually takes place on the feeding site (young damar leaves and shoots), and lasts for several hours, male and female being in the end-to-end position. Very often at least one of the bugs feeds during mating.

Eggs are laid on a wide variety of plants in the understorey (on Shorea javanica as well as many others), mostly on the upper side of the leaves. Over 40 different plant species were recorded for ovipositing. Eggs are laid continuously during two or three days and glued on the leaf in usually hexagonal clusters of about 70 to 120 eggs.

The female P. tenangau n. sp. sits on the leaf covering the eggs with her body, even after egg laying is finished The females stay on the eggs and defend them under all circumstances. When approached too closely, almost all project a spurt of defensive liquid towards the attacker. Some also buzz their wings. When held by hand, they hold on to the leaf with their claws and have to be taken away from their eggs by force. Slightly yellowish, soon turning white (after ± l day), then pink, the eggs begin to darken further after four to five days and hatch in about nine to eleven days.

Hatching was observed in the early morning hours. The nymphs hatch and crawl up under the abdomen of the female in a matter of minutes. Newly hatched nymphs are yellow-orange, turning red after about an hour and eventually black with markings. They hold on to the abdominal segments of the female or to each other. After all the nymphs have hatched (a process of up to 3 -4 days), the female bears a large compact cluster of phoretic nymphs under the abdomen from the apex of the abdomen to just behind the posterior coxae. This allows the female to still walk and usually also to fly. After hatching is finished, it stays on the leaf for a period of up to two days before crawling or flying away with the nymphs. Some females were observed flying straight up into the upper storey of the damar agroforest.

Phoretic nymphs in the damar garden were able to stay alive for more than two weeks in mosquito-netting bags. They were observed staying under the abdomen of the female for at least 17 days. Hatched nymphs in the laboratory were unable to survive for more than 4-5 days. They stay together for a few days in a compact ball on, or near, the egg cluster. When the female was taken with them, they stay phoretic as long as the female is alive.

Many nymphs of different stages Were observed in the damar agroforest feeding on Shorea javanica , crawling around the ground or on plants, sitting on the leaves, moulting on and under leaves. Nymphs were sometimes seen racing up plant stems and tree trunks. They crawl up the tree trunk at a speed of l to 2 rn/min and disappear into the canopy. Aggregations of last instar nymphs were observed in certain areas of the damar agroforest. The last three instar nymph seem to be able to direct their ejection of defensive fluid by moving their abdomen in the direction of the attacker.

It can be deduced from the field observations of beginning of egglaying and first eclosion of adult that the postembryonic development lasts at least two months.

Damage. The defensive secretions 0f nymphs as well as adults cause browning and necrosis on young shoots and very young leaves after one day. The amount of production loss estimated by farmers varies from 20% to 60% less damar resin production until new leaves have grown. The defensive secretions can cause staining and burning of human skin, and severe burning of human eyes. Since the repugnatorial fluid is discharged in a strong horizontal backward jet, and does not have the typical bug smell, it is likely that it is not discharged from the scent glands of the bugs (adult metathoracic glands and nymphal dorso-abdominal glands), but instead from the rectum. However, the exact source of the fluid has not been verified in detail.

Enemies.— Predation by different species of ants was observed on nymphs trying to climb back on the trees. Ant predation was also observed on eggs, but only after the adult females were disturbed or removed. This latter observation seems to confirm the benefits of the maternal care against predation of eggs, although if in a few cases, undisturbed females have been found guarding empty eggs, which suggests that some predators are capable of stealing eggs even when the female is guarding them.

However, probably the most important factor in controling the bug populations is Ooencyrtus sp. n. near caurus Huang & Noyes, 1994 ( Hymenoptera , Encyrtidae ; det. J. Noyes, BMNH), which has often been observed ovipositing on the eggs of P. tenangau n. sp., undisturbed by the guarding female. O. caurus is very close but differs in a slightly narrower frontovertex and much deeper sculpture on the scutellum (J. Noyes, pers. comm. 2006). Voucher specimens of this undescribed species of Ooencyrlus have been deposited in BMNH, ISNB and MZB _ The population of this wasp increased as the breeding season of the bug advanced.