Ploiaria metapterina, Rédei, 2007

Rédei, D., 2007, New And Little-Known Thread-Legged Assassin Bugs From Australia And New Guinea (Heteroptera: Reduviidae: Emesinae), Acta Zoologica Academiae Scientiarum Hungaricae 53 (4), pp. 363-379 : 365-372

Ploiaria metapterina sp. n.

( Figs 1–7 )

Type material. Holotype (f): “ AUSTRALIA, N.S.W. \ Sydney , Ingleside \ Katandra Bushland \ Sanctuary, 159 m ” [printed]; “ 33°40’4”S; 151°16’8”E \ 19–21. XI. 2000. \ leg. A. Podlussány, \ G. Hangay & I. Rozner ” [printed]; “ Holotypus \ Ploiaria \ metapterina sp. n. \ det. Rédei, 2005” [type label with red borders, handwritten+printed]; deposited in the ANIC.

Description. Apterous female.

Colour. General body colour dark brown. Head dark brown, laterally lighter posterior to eyes; labium dark brown, segment III somewhat lightened apically; antennae rather uniformly light brown. Pronotum dark brown, distinctly darker ventrally; meso- and metathoracic pleura dark blackish brown, meso- and metanota light brown. General colour of fore legs dark brown, apex of coxa distinctly darkened, femur with a rather distinct dark subapical annulus, tibia darkened apically, tarsus light brown. Mid and hind legs rather uniformly light yellowish brown except coxa and trochanter which are dark brown. Abdominal venter uniformly black, spiracles with narrow but distinct yellowish brown margin; abdominal tergites (mediotergites) dark brown, with a very narrow, hardly perceptible medial line as well as a pair of indistinct lateral spots on tergites II–V, furthermore a pair of more or less distinct spots at posterolateral angles of tergites II–VII (larger and more apparent on tergites VI–VII) lighter.

Structure. Body relatively stout, rather dull, smooth, only with few, very short, hard to observe hairs.

Head as shown in Figs 1 and 2 , rather short, about 1.45 times longer than diatone, with deep interocular furrow. Preocular part about 1.85 times longer than postocular in dorsal aspect, strongly elevated before eyes, declivent anteriorly, its lateral outline very slightly diverging anteriorly in dorsal aspect; antenniferous tubercles situated distinctly closer to apex of head than to eyes; postocular part short, its lateral outline widely rounded in dorsal aspect, about 1.3 times wider than width of preocular part, dorsal outline conspicuously declivous posteriorly in lateral aspect, forming distinct angle with neck; a pair of small but distinct, rounded tubercles present anterior to eyes and another pair within interocular furrow. Eyes small, laterally prominent, far remote from ventral and dorsal outlines of head in lateral aspect; diatone about twice as wide as interocular distance. Antenna ted in Figs 6 and 7 . Scales = 1.0 mm to Figs 1–5 , 0.5 mm to Figs 6–7 .

gracile, segment I longest, about 1.6 times longer than segment II, distinctly bent; segment III short, its length about 1/3 of segment II. Labium rather straight and narrow, segment I only very slightly shorter than segment II, reaching about level of antenniferous tubercles; segment II distinctly surpassing level of anterior border of eye; segment III longer than previous segments, projecting between bases of fore coxae. Thorax: Pronotum as shown in Figs 1 and 2 , rather short and stout, about 1.6 times longer than its greatest width, subdivided into fore and hind lobes; hind lobe extremely short, collar-like, about 0.7 times as wide as fore lobe in dorsal aspect; meso- and metathorax short, mesonotum about 0.6 times, metanotum about 0.25 times as long as pronotum, both with a pair of short lateral projections. Legs: Fore leg as in Fig. 3 , rather stout; coxa cylindrical, about 8.8 times longer than its greatest width; trochanter simple, nearly glabrous, only with few simple hairs; femur elongate, about 8.6 times longer than its greatest width (near its base), about 1.4 times longer than coxa, ventral surface armed with two rows of spiniferous processes. Posteroventral series ( Fig. 4 ) composed of about 5–6 long spines inserted on distinctly elongate basal processes (one of them at base of femur as well as its basal process particularly long, this spine without basal process about 1.6 times longer than width of femur), and about 12–13 more or less shorter spines inserted on very short, almost wart-like basal processes; anteroventral series ( Fig. 5 ) composed of 6 long and about 6 somewhat shorter spines inserted on very short, almost wart-like basal processes; series interrupted at base, a single long spine basad of interruption, two long spines with extremely closely situated, almost connected basal processes apicad of interruption. Tibia very short, stout, about 4.7 times longer than wide, its length about 1/3 of femur, its ventral surface with few small denticles; tarsus heavily sclerotized, nearly bare, rather narrow, slightly more than 0.9 times as long as tibia, with about 7–8 peg-like spines on its ventral surface, three-segmented, intersegmental articulations hardly perceptible, segments I and III subequal in length, segment II somewhat longer. Pretarsus with two claws of unequal shape and size: anterior (inner) one very long, slender, nearly straight, only very slightly arched, apically not curved; posterior (outer) one very short and stout, less than half as long as anterior claw. Mid and hid legs elongate and delicate, tibiae about 1.4 times longer than respective femora; hind tibiae somewhat longer than body length; tarsi minute. Abdomen of female elliptical, about three times as long as wide; apex with external female genitalia as in Figs 6 and 7 , tergite IX strongly declivent, apically widely excised, gonocoxites greatly exposed.

Measurements (in mm): Body length 5.7. Length of head 0.81, of preocular part 0.39, of postocular part 0.21; width across eyes 0.56, interocular distance 0.28, greatest width of preocular part 0.35, of postocular part 0.46; length of labial segments I: II: III = 0.22: 0.24: 0.38; length of antennal segments I: II: III: IV = 2.65: 1.70: 0.55: ~0.8(?) (segment IV strongly deformed, probably incomplete in holotype). Medial length of pronotum 0.91, of fore lobe 0.84, of hind lobe 0.07; greatest width of fore lobe 0.56, of hind lobe 0.39; length of mesonotum 0.56, of metanotum 0.21. Length of fore coxa 1.23, femur 1.69, tibia 0.59, tarsus (without claw) 0.55; mid femur 2.88, tibia 4.08, tarsus 0.43, hind femur 4.20, tibia 5.85, tarsus 0.21. Length of abdomen 3.2, greatest width 1.1.

Etymology – The specific epithet, metapterina , refers to the subbasal tubercle of the posteroventral series of fore femur, which is, just like its spine, much larger than any other armature elements on the segment, endowing the fore leg an appearance superficially resembling of the tribe Metapterini .

Comparative notes. As frequently the case, only a single adult, unfortunately a female, is available of Ploiaria metapterina sp. n. However, it differs very sharply in important external characters from all of its known congeners. It can easily be distinguished from nearly all other Australian species by its glabrous fore trochanters, which entirely lack protuberances and spiniferous processes. Among the ten Australian species of Ploiaria listed by CASSIS and GROSS (1995), only P. guttata WYGODZINSKY, 1956 and P. musgravei WYGODZINSKY, 1956 share this character with the new species. Both P. guttata and P. musgravei have, however, a conspicuous, contrasting dark and light pattern: the former species can easily be recognized by its whitish pronotum and dark mesonotum, the latter by its distinctly annulate fore legs.

The fore leg of Ploiaria metapterina sp. n. is very characteristic. The combination of the following features is unique within the genus: (1) trochanter nearly glabrous, having only few simple hairs; (2) femur with very few spiniferous processes and with a particularly long spiniferous process, which is much longer than width of femur, at the base of the posteroventral series; (3) tibia very short, its length only about 1/3 of femur.

Because no Ploiaria species have been described or reported from Australia since WYGODZINSKY (1956), there is no need for preparing a new key to the Australian species. Ploiaria metapterina sp. n. will run to couplet 3 in WYGODZINSKY’ s (1956: 163) key. The following modification to couplet 3 will allow the recognition of the new species.

3 Fore trochanter on ventral surface with at least one distinct spinelike bristle 4

– Fore trochanter without any distinct spinelike bristles 3a

3a Head and pronotum with complex dark and light pattern. Anteroventral series of fore femur composed of about 23 spines apicad to basal interruption. Fore femur about 1.2 times as long as fore tibia and tarsus (without claws) taken together; fore tibia slightly less than half as long as fore femur. Only macropterous morph known P. musgravei

– Head and pronotum uniformly dark brown. Anteroventral series of fore femur composed of about 11–12 spines apicad to basal interruption. Fore femur about 1.4 times as long as fore tibia and tarsus (without claws) taken together; fore tibia extremely short, about 0.35 times as long as fore femur. Only apterous morph known P. metapterina sp. n.

The Australian Ploiaria metapterina sp. n., P. guttata and P. musgravei may form a monophyletic group within Ploiaria characterized by the combination of the following characters: (1) trochanter nearly glabrous, without spiniferous processes or strong setae; (2) fore leg relatively short and stout; (3) fore femur with relatively few spiniferous processes; (4) tibia short. All of these characters are also found occasionally elsewhere in the genus, however, their unique combination in these three species makes aquisition from a common ancestor rather probable. Also, the geographic distribution of the species seems to support this hypothesis. The fore leg structure of the new species, including the very characteristic, strongly asymmetrical claws of the fore tarsus, resembles the one of P. guttata and the two species appear closely related.

Habitat notes. The holotype was collected in a wet and closed sclerophyll forest on sandy loam soil (A. PODLUSSÁNY, pers. comm.).

Ploiaria biroi WYGODZINSKY, 1966 apterous female

( Figs 8–13 )

Ploiaria biroi WYGODZINSKY, 1966: 171 ( Ploiaria ) [ New Guinea: Stephansort, Astrolabe Bay; holotype (m) HNHM! (see remark below)]

Material examined. NEW GUINEA: Leuvomba Plant, 8 miles S of Lae, 11. IV. 1965, Nr. 26, leg. J. BALOGH & J. J. H. SZENT-IVÁNY (1 apterous f); deposited in the HNHM .

Description of apterous female. Colour. Head stramineous; clypeus, a pair of dorsal longitudinal spots posterior to antenniferous tubercles, a pair of dorsal longitudinal spots posterior to interocular furrow, a pair of lateral longitudinal stripes between antenniferous tubercles and base of head (narrowly interrupted before eye), and ventral surface of head anteriorly light castaneous. Labium castaneous, with stramineous colouration at intersegmental articulations. Antennal segment I castaneous, distinctly darkened towards its apex, with a basal and a subapical annulus light stramineous. Pronotum stramineous dorsally, castaneous laterally; meso- and metathoracic terga stramineous, pleura dark castaneous. Abdomen dorsally stramineous with castaneous pattern, ventrally dark brown. Fore coxa rather uniformly castaneous except a narrow apical stramineous annulus; trochanter castaneous; femur castaneous with distinct stramineous pattern as in Fig. 10 ; basal 1/5 and apical 2/5 of tibia castaneous, remaining part stramineous; tarsus castaneous with a narrow basal stramineous annulus. Mid and hind legs castaneous, mid femur with a rather wide subapical and tibia with a narrower subbasal whitish annulus ( Fig. 12 ), femurotibial articulation of hind leg widely whitish ( Fig. 13 ).

Structure. Body elongate, rather smooth, only with few, very short, hard to observe hairs (with the exception of appendages). Head as in Figs 8 and 9 , elongate, preocular part about twice as long as postocular, diatone about 2.15 times greater than interocular distance. Labium: Segment I attaining about middle of preocular part of head, segment II shortest, distinctly surpassing anterior margin of eye, segment III longest, surpassing base of head, projecting between anterior acetabula. Thorax: Pronotum as in Figs 8 and 9 , rather short and stout, about 1.8 times longer than its width; lateral outline of fore lobe subparallel, strongly converging posteriorly in its posterior fourth in dorsal aspect; hind lobe very short and narrow, distinctly narrowing posteriorly. Mesothorax rather elongate, metathorax much shorter; mesonotum about 2.6 times longer that metanotum. Legs: Fore leg as in Fig. 10 , elongate, rather slender; coxa subcylindrical, elongate; trochanter without spiniferous processes, only with a few bristles; femur long and slender, about 1.1 times longer than coxa, with short, semi-erect pilosity as well as with a large number of long, fine hairs between the two series of spiniferous processes; posteroventral series with 12 very long spiniferous processes, length of the basal processes of the apical three spines subequal to the width of fore femur; anteroventral series interrupted subbasally, composed of about 23 long spines inserted on very short basal processes ( Figs 10 and 11 ); tibia about 0.47 times as long as femur, its ventral surface with a single row of short, erect spines and a row of long, rather strong spinelike setae; tarsus about 0.65 times as long as tibia, ventral surface with a row of small spines. Mid and hind legs long and slender, with short, adpressed pubescence. Abdomen elongate, narrow, rather parallel-sided. Collapsed in the single examined specimen (apparently the specimen was mounted on card from alcohol) and not allowing proper examination and description of female genitalia.

Measurements (in mm). Body length 9.8. Length of head 1.05, preocular length 0.52, postocular length 0.28, diatone 0.69, interocular distance 0.32. Length of labial segments I: II: III = 0.38: 0.28: 0.45. Length of antennal segments I: II: III = 5.70: 3.95: 1.95 (segment IV incomplete in examined specimen). Medial length of pronotum 1.12, width of fore lobe 0.63; medial length of mesonotum 1.12, of metanotum 0.42. Length of fore coxa 2.38, femur 2.57, tibia 1.22, tarsus 0.81; length of mid femur 5.75; length of hind femur 8.05.

face, 12 = femurotibial articulation of mid leg, 13 = same of hind leg. Scale = 1.0 mm to all figures.

Remarks. Ploiaria biroi was described from a single macropterous male from New Guinea and its female remained unknown until now. The apterous female, reported herein for the first time, differs in several aspects from the male holotype of P. biroi . Some of the differences, such as the differently structured thorax, can be attributed to pterygopolymorphism, others are commonly encountered sexual differences (e.g. the larger eyes of male). Nevertheless, the difference of some characters, most notably some of the colour patterns (dorsally stramineous pronotum, whitish annuli on mid and hind legs in female), is rather curious and suggests that there is the slight possibility that the examined female represents an undescribed species closely related to P. biroi . The similarity of the highly characteristic fore legs, however, suggests that the specimen described above is the apterous female of P. biroi .

Only the macropterous male can be identified by using the identification key presented by WYGODZINSKY (1966: 163). The following modification on WYGODZINSKY’ s key will allow the additional recognition of the apterous female of this species.

27 Posteroventral series of fore femur composed of 10–11 very long processes, each bearing a single long spiniform seta apically, some of these combined with their base several times longer than diameter of fore femur P. biroi

– Posteroventral series of fore femur composed of much shorter processes and setae, none of these longer than diameter of fore femur 27a

27a First and second segments of fore tarsus elongate, of about identical length, third very short (fig. 44D, F) P. antipoda

– First segment of fore tarsus elongate, second and third short (Figs 52C; 53F) 28

It may be noted that the holotype of P. biroi is deposited in the HNHM and not in the BPBM as stated in the original description by WYGODZINSKY (1966: 173). However, since it was collected by L. BÍRÓ, who deposited nearly all of his material at the HNHM, WYGODZINSKY’ s record on the type depository is most probably simply a lapsus calami .

Habitat notes. According to the records of J. BALOGH, the examined specimen was collected on the ground in a coffee plantation.

Bargylia STÅL, 1866

Bargylia STÅL, 1866: 163 . Type species by subsequent designation ( WYGODZINSKY 1951: 611, 616): Emesa iuncea ERICHSON, 1842 sensu STÅL, 1874 (misidentification; = Bargylia stali WYGODZINSKY, 1951 ).

Bargylia currently comprises four endemic Australian species (MALDONA-

DO CAPRILES 1990, CASSIS & GROSS 1995). An additional species is described below.

Figures

Figs 1–7. Ploiaria metapterina sp. n., apterous female: 1 = head, thorax and base of abdomen, dorsal view, 2 = same, lateral view, 3 = right fore leg, anterior view, 4 = posteroventral and 5 = anteroventral series of fore femur, 6 = apex of female abdomen, lateral view, 7 = same, posterior view. Hairs omit-

Figs 8–13. Ploiaria biroi Wygodzinsky, apterous female: 8 = head and thorax, lateral view, 9 = head and pronotum, dorsal view, 10 = right fore leg, posterior surface, 11 = left fore femur, anterior sur-