Plinthisus (Nanoplinthisus) peninsularis Sweet & Slater, 2004, n. sp.
Creators: name: Sweet, Merrill H.
name: Slater, James A.
Publisher: name: Zenodo
Year: 2004
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Rhyparochromidae
Plinthisus
Plinthisus peninsularis

description: Plinthisus (Nanoplinthisus) peninsularis n. sp.
(Fig. 6, 14, 24, 34, 45, 46, 62, 63, 76, 92, 93, 106, 118)
Brachypterous male. Nearly uniformly dark chocolate brown with abdominal tergum black and thoracic pleura lighter brown than dorsum. Legs and antennae concolorous yellowish brown, profemora somewhat darker. Narrow explanate pronotal margins a contrasting red­brown. Body surface with dull granulose­pebbled texture, with numerous small inconspicuous, evenly scattered punctures on dorsum. Interior profemoral surface highly polished, iridescent from minutely crazed surface (? a plectrum). Propleuron finely striate (? a stridulitrum) with a few scattered punctures. Prosternum clothed with very short inconspicuous semi­decumbent sericeous hairs, each puncture bearing such a hair. Antennae with longer forward­directed pale hairs less than width of antennal segments. Relatively short, thick trichobothriumlike (Fig. 14) seta on eye, antenniferous tubercle, tylus, gena, and outside proximal surface of protibia, pair on vertex 0.10 long, 0.22 apart, 0.05 from eye. [Abdominal sterna with 2 trichobothria on each side of meson of 3 and 4; anterior trichobothrial hairs of 5 and 6 very long; posterior pairs of hairs of 5, 6 and 7 much shorter, especially ventral hairs; the pairs equidistant (0.04) between spiracle and posterior margin of sterna.]
Head non­declivent, nearly flat across vertex. Tylus very slightly exceeding juga, not attaining distal end of 1st antennal segment. Tylus broad, nearly flat, width 0.11, length 0.20. Tylar sutures lightly incised, converging slightly caudad. Juga strongly convex, nearly carinate, giving apex of head a blunt appearance. Lorum and gena lightly concave. Antenniferous tubercles very short, invisible from above, insertion of antenna below and at front margin of eye. Eyes broadly in contact with anterolateral pronotal angles; mesal margins of eyes divergent anteriorly (Fig. 6). Eye oval, almost kidney­shaped, relatively small, of about 90 facets; eye length 0.09, height 0.17. Ocelli absent. Bucculae high (0.09), height greater than width of labial segment 1, becoming a ridge at level of front margin of eye; ridges terminating at base of head in a broad point. Telescoped posterior part of head swollen ventrally, length 0.09. Visible head length 0.40, width across eyes 0.46; interocular space 0.30, height above eye 0.01, preocular distance 0.23.
Pronotum broader across anterior 1/3 than across humeral angles; lateral margins narrowly but distinctly explanate; anterior margin deeply concave, anterior corners extending anteriorly to level of middle of eye; posterior margin nearly straight, only slightly overlapping hemelytra. Pronotum with anterior lobe strongly convex, sloping down abruptly caudad to form very narrow flattened posterior lobe; height anterior lobe above lateral margin 0.10. Pronotum medial length 0.68, posterior lobe length 0.07; maximum width 0.82, width across humeri 0.78; [dorsal collar length 0.06 (cleared)]. Scutellum flat; length 0.39, width 0.60. Mesoscutum weakly differentiated from scutellum by sulcus; not exposed laterad, but continuous with mesepisternum. Hemelytron (Fig. 6) pad­like, corium and clavus fused; basally fused with mesoscutum; membrane remnant absent. Caudal (distal) hemelytral margin truncate, at right angles to longitudinal body axis, extending caudad to anterior half of 4th abdominal tergum; base of hemelytra depressed at level of mesoscutum sulcus. Hemelytra broadly arcuate laterad, much broader than maximum width of pronotum; lateral margins of hemelytra sharply carinate, narrowly clasping grooved pterothorax (Fig. 24). Hemelytron length 0.70, maximum width 0.56; commissure length 0.29; distance posterior margin hemelytra to apex abdomen 0.74. [Metanotum narrow, pale, desclerotized, much exceeded caudad by scutellum. Metathoracic wing (Fig. 34) greatly reduced, length 0.14, width 0.07. Stridulitrum sclerite length 0.13, width 0.05, bearing about 40 equisized small teeth in 5 staggered rows. (In female, metathoracic wing absent; metanotum membranous.)] Propleural pore very small and evidently closed. Posterior part of proepimeron and anterior part of mesepisternum deeply constricted, but not set off by sulcus. Mesepimeron and mesepisternum produced below groove which receives hemelytra, the mesepimeron just visible from above. Metathoracic scent gland auricle (Fig. 24) elongate, scimitar­shaped, basally angled caudad, then abruptly bent cephalad at a right angle, distal end widened and reaching mesopleuron and smooth area just ventral of hemelytron at anterodorsal angle of scent area. Granulose scent area covers all but narrow dorsal margin of metepisternum, and extends onto posterior margin of mesepisternum. Metapleural flange not set off by groove from metepisternum; posterior margin of flange nearly straight. Prosternum elongate, length 0.61; ventral collar weakly delimited by sulcus of fine punctures, collar length 0.09. Prosternum and mesosternum transversely grooved; meso­ and metasternum not strongly produced; xyphi of all three sterna sharp. [Metacoxal cavity closed internally by narrow bridge. In female, metacoxal cavity narrowly open. Mesendosternite broad with concave apex; mesendotergite very short, with cup­shaped apex, remote from mesendosternite.]
Abdomen length 1.05, maximum width 1.05. Abdominal terga distinctly convex; caudal margin of tergum 7 truncate, nearly straight. Abdominal sternal sutures 3–4 and 4–5 strongly ridged, straight. [Spiracles of 5 and 6 one­third distance (0.08) from posterior margin of segments. No spiracle visible on segment 8 (also lacking in female). Terga 1 and 2 (Fig. 45) short, pale, width 0.54. Plectrum dark, sclerotized; width 0.12, length 0.07, striae 0.9 µ apart. Tergum 3 relatively long, with distinct low transverse carina along posterior margin. Tergal sutures 4–5 and 5–6 not dovetailed; sutures curve caudad so that tergum 6 is shorter than tergum 4, 5 or 7. Maximum width of terga 0.88; medial lengths: 1­ 0.12, 2­0.02, 3­0.05, 4­0.26, 5­0.25, 6­ 0.13, 7­0.24. Terga 3 to 7 inflexed and grooved laterad to receive mesal margin of connexivum. Epipleurites 3–5 narrow, width 0.02. Connexivum relatively narrow, hypopleurite widths: 2­0.02, 3­0.07, 4­0.09, 5­0.09, 6­0.09, 7­ 0.07; lengths: 2­0.04, 3­60.12, 4­0.18, 5­0.22, 6­0.31, 7­0.24. Hypopleurites 2 and 3 nearly fused; hypopleurite junction 3–4 oblique, others nearly transverse. Anterior scent gland scar absent (gland absent in nymph); scar widths: 4–5: 0.18, 5–6: 0.16. Tergum 7 and sternum 7 with strong shelf­like internal margins to receive segment 8 and genital capsule. Sternum 7 with two large anterior apodemes 0.12 apart. Genital capsule (Figs. 62 & 63) width 0.31; posterior rim lip­like, extending ventrad as a carina; parandria apices bilobed. Epiproct slender (Fig. 62); paraprocts ventrally fused; paraprocts and epiproct bearing relatively long hairs; anal sclerites small, paired. Clasper (Fig. 76) shank narrow with outer projection sharply pointed; blade short, straight, with carina on frontal face. Phallus (Figs. 92 & 93) with gonoporal process of basal seven coils with thin membranous sleeve, distal five coils very slender; helicoid process absent. Sperm reservoir large; wings absent; holding sclerites shorter than reservoir body. Phallotheca with dorsal (frontal) part unsclerotized. An unusual sclerotized bulb, probably an accessory pump (ap), attached by slender duct (vas deferens?) to phallus (Figs. 92). (In female, terga 1–2 membranous, tergum 3 longer (length 0.12), with weak transverse posterior carina. Tergum 8 with no submesal sutures; anterior margin inflexed. Tergum 9 relatively long; epipleurite 9 a little longer, its apodeme large, half as long as medial anterior apodeme; hypopleurite 9 cleft with large pore at ventral corner. Valvula length 0.55. Spermatheca [Fig. 106] with hemispherical bulb; sclerotized distal duct distally enlarged, with 3 narrow coils and basal swelling; unsclerotized basal duct moderately long.)]
Profemur (Fig. 118) enormously incrassate, length 0.60, width 0.25; convex above and below, sulcate beneath on distal third; armed with two rows of spines, inner row with 3 large spines, each with a small apical spur. Procoxa with 2 semicircular teeth. Protibia bent, slightly enlarged basad to fit in femoral sulcus; armed inside with row of small tubercles; distal apex enlarged, armed with blade­like outside posterior spine, and a spur inside; protibial length 0.55, distal width 0.12. First protarsomere armed with tiny tubercles. Mesotibia with 2 rows of 3 spurs; metatibia with row of four spurs; metatibia length 0.60, medial width 0.05; metatarsomere lengths: I 0.15, II 0.06, III 0.04. Labium just exceeding procoxae, nearly attaining mesocoxae [female to mesocoxae], 1st segment exceeding base of head; labial segment lengths: I 0.28, II 0.25, III 0.20, IV 0.20. Antennal segment 1 terete, segments 2 and 3 subclavate, segment 4 fusiform, width 0.08; antennal segment lengths: I 0.16, II 0.32, III 0.25, IV 0.30. Total body length 2.38.
Material Examined. HOLOTYPE: Brachypterous male. SOUTH AFRICA: Cape Province: Cape Point Nat. Res., 30.I.1968 (J. A. & S. Slater, R. T. Schuh, M. Sweet). In National Collection of Insects, Pretoria, South Africa.
PARATYPES (all brachypterous): SOUTH AFRICA: Cape Province: 6 m, 5 f, same data as holotype. 5 m, 8 f (2 m, 3 f dissected), same locality, 15.IX.1967 (M. H. Sweet no. 3). 2 m, 6 f, same locality, 7.XII.1967 (M. H. Sweet no. 99). 32 m 12 f (3 m 3 f dissected), 2 mi. N. Muizenberg, Cape Peninsula, 100', 16.IX.1967 (M. H. Sweet no. 4). 4 m 8 f, Muizenberg Mt., Cape Peninsula, 200', 8.X.1967 (M. H. Sweet no. 23). 1 f Red Hill, Cape Peninsula, 900', 5.XII. 1967 (M. H. Sweet no. 2). 10 m 19 f, Simonstown, Cape Peninsula, 3.XII. 1967 (M. H. Sweet no. 93). 5 m, 6 f, Hermanus Beach, 2.I. 1968 (S.S.S.S.). In J. A. Slater and M. H. Sweet collections.
Etymology. The specific name peninsularis is formed from the Latin peninsula and ­ aris, a suffix meaning pertaining to, to give recognition to the concentration and abundance of this species in the Cape Peninsula of South Africa.
Discussion. P. peninsularis is one of a remarkable species complex restricted to southern Africa which consists of at least 15 additional new species, most of which are in arid areas or arid microhabitats. Some are sympatric, others are allopatric. One feels that every isolated koppie appears to have its own resident species! As with the Fynbosi group, most of the species would not have been recognized if we had not studied the species in the field, reared them to obtain the immature forms, and performed some simple mating experiments in the laboratory. Astonishingly, what appeared to be sibling species differed remarkably not only in their genitalia, but also in the presence or absence of dorsal abdominal scent glands, a character more usually associated with family or subfamily taxa, not species taxa, which may indicate the antiquity of the genus Plinthisus. Coloration should be used with caution as tanning is slow and subteneral specimens are common.
The species­group Peninsularis, as noted in the key, is distinctive among the Ethiopian Plinthisus in having a granulose­pebbled cuticular surface, which is similar to that of group III in the Australian Plinthisus fauna. Another unusual feature, perhaps unique to the Lygaeoidea, is the presence in this species of a sclerotized structure in the vas deferens, perhaps an accessory sperm pump (ap, Figs 62 & 92).
We place the Peninsularis group in Wagner's subgenus Nanoplinthisus because the hemelytron is truncate at the level of tergum 4 and bears no membrane remnant and the clasper is straight with a carinate blade.
LAMPRUS SPECIES­GROUP
description: Published as part of Sweet, Merrill H. & Slater, James A., 2004, An analysis of species­groups of the genus Plinthisus Stephens (Hemiptera: Rhyparochromidae) in the Ethiopian Region with the description of eight new species, pp. 1-56 in Zootaxa 533 on pages 26-30, DOI: 10.5281/zenodo.157231