The Orsillini of New Zealand. (Hemiptera, Lygaeidae.)
[Read before the Nelson Institute, May, 1941; received by the Editor, December 23, 1941; issued separately, June, 1942.]
The tribe Orsillini contains the nearly cosmopolitan genus Nysius Dallas (1852) and about twenty additional genera which are more or less restricted to particular islands or continental regions. The most unique types of Orsillini, as of many other groups, are found in Hawaii, New Zealand, and the Galapagos. I have recently monographed the Hawaiian Orsillini (1941), recording a total of eighty-seven distinguishable forms which pertain to five different genera. All but one of these genera are confined to the Hawaiian Islands and all of the species are unique. This work was possible only after years of diligent collecting by various entomologists followed by one year of intensive work of my own. From the remarkable diversity exhibited by the limited number of specimens at hand, it appears likely that the New Zealand Orsilline fauna will prove to be just as unique, though possibly somewhat smaller, than that of the Hawaiian Islands. Moreover, it would appear that our knowledge of these aberrant and possibly primitive forms has scarcely reached the stage which the Hawaiian fauna passed with the death of G. W. Kirkaldy in 1910.
The first New Zealand species of Orsillini was described by Fabricius (1794) as Lygaeus clavicornis from material labelled “Selandia” and mistakenly assumed to be from “Hafniae” on the Danish island of “Selandia.” Clavicornis was later removed to Coreus (Fabricius, 1803), but inasmuch as there was already a Coreus clavicornis proposed as new on a previous page of the same work, Fabricius renamed this last as typhaecornis in his “emendanda.” Strobilotoma typhaecornis (Fabr.) is now a well-known European Coreid. The New Zealand Lygaeid was later described by Dallas (1852) as Nysius zealandicus and was made the type of a new sub-genus, Rhypodes, by Stäl (1868). Buchanan-White added two more species, Nysius anceps and huttoni in 1878. Here the matter rested for a half a century until Evans, (1929a) reviewed “the genera included under Nysius, auctt.,” made Nysius anceps the type of a new genus, Hudsona, and made clavicornis Fabr. (= zealandicus Dallas) the type of a new genus Myersia. Soon after this, Myersia was sunk as a synonym of Rhypodes (1929b) because their genotypes are identical. Thus we have, at present, three described species, one belonging to the cosmopolitan genus Nysius and one each belonging to the endemic genera Rhypodes and Hudsona.
The present paper deals with a collection of eighty-eight specimens received from Messrs. W. E. China (British Museum of Natural History), H. G. Barber (United States National Museum) and G. V. Hudson. Much of this material was collected by the accomplished Hemipterist, J. G. Myers, from 1921 to 1923, and by G. V. Hudson from 1921 to 1938. This collection contains not only fine series of the three previously known species, but also representatives of five additional species which are described below. Several uniques probably represent still different species, but it seems best to be conservative in the description of new species at this stage. Further field work will doubtless reveal many important additions to this remarkable fauna.
The New Zealand Orsillini are so peculiar that no relatives of the endemic genera are known from elsewhere. Nysius huttoni Buchanan-White, however, is allied to the Hawaiian blackburni Buchanan-White and to Nysius baeckstroemi Bergroth from Juan Fernandez. The new genus, Brachynysius, is apparently a remarkable off-shoot from typical Nysius. Stäl originally separated Rhypodes as a subgenus because of the sublateral lobes on the posterior margin of the pronotum. It now appears doubtful if this character is even of specific value, but I have retained the generic name for its type, clavicornis (Fabr.), which is obviously of a different stock from typical Nysius. The other species described below, e.g., myersi, stewartensis, chinai, and sericatus, differ so considerably from the genotype that, according to standards elsewhere in the world, each should perhaps be made the type of a new genus. However, I have chosen to lump these together with zealandicus into a single, possibly unnatural genus, until further material is at hand and more extensive field work has been done.
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|1. Hemelytra reduced to short pads which reach only a short distance on to base of abdomen, nearly as broad apically as long, 13: : 15, the corium definitely delimited, subtriangular, with veins distinct; membrane very short, one-tenth as long as hemelytra. Antero-lateral angles of pronotum produced laterally as small tubercles.||Hudsona anceps (Buch.-White)|
|Hemelytra larger, usually exceeding tip of abdomen. Pronotum without minute antero-lateral tubercles||2|
|2. Hemelytra distinctly convex, costal margins strongly rounded beyond basal fourth. Membrane small, exceeding level of apices of coria by less than one-fourth the total length of membrane, without apparent veins||Brachynysius convexus n.gen. and sp.|
|Hemelytra subflattened, the costal margins not strongly rounded. Membrane much larger, extending beyond level of apices of coria for a distance almost half the total length of membrane, veins distinct||3|
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|3. Bucculae decreasing only slightly in height posteriorly, reaching to base of head. Size small, less than 4 mm.||Nysius huttoni Buch.-White|
|Bucculae decreasing in height at level of antenniferous tubercles, not reaching base of head. Size larger, over 5 mm.||Genus Rhypodes||4|
|4. Ground colour ferrugineous with black markings. Head and pronotum very coarsely punctured, the punctures of pronotal disk less than one puncture width apart. Hind margin of pronotum more or less distinctly produced sublaterally into rounded or subtriangular plate-like lobes||Rhypodes clavicornis (Fabr.)|
|Ground colour pale, ochraceous, marked with fuscous or black. Head and pronotum less coarsely punctate, the punctures either shallow or separated by more than one puncture width. Hind margin of pronotum without sublateral lobes||5|
|5. Last two antennal segments subequal in length. Sides of pronotum straight||Rhypodes sericatus n.sp.|
|Fourth antennal segment distinctly longer than third. Sides of pronotum swollen at level of callosities||6|
|6. Antennae short and thick, the second segment about four-fifths as thick at middle as front tibiae basally. Body subflattened above, the head and pronotum only feebly declivous. Clavus and corium in great part pale, ochraceous||Rhypodes myersi n.sp.|
|Antennae more slender, the second segment scarcely more than half as thick at middle as front tibiae basally. Body not noticeably flattened above, the head and pronotum more strongly declivous. Clavus and corium extensively marked with brown||7|
|7. Body nearly three times as long as broad. Head and pronotum moderately declivous. Female genital cleft deep, the fourth and fifth visible ventral segments concealed beneath third at middle||Rhypodes chinai n.sp.|
|Body shorter and very robust, about two and one-half times as long as broad. Head and pronotum strongly declivous. Female genital cleft shallow, both fourth and fifth ventral segments exposed at middle||Rhypodes stewartensis n.sp.|
Hudsona anceps (Buchanan-White).
Nysius anceps Buch.-White, Ent. Month. Mag., 15: 32–33, 1878.
Hudsona anceps, Evans, Bull. Ent. Res., 19: 353, 1929.
One male is at hand from the British Museum, Otago, New Zealand, Pascoe Coll., determined by Buchanan-White. Five other specimens are from the collection of H. G. Barber as follows: one male, Darfield, New Zealand, August 15, 1923, J. G. Myers; two females, Taitapu, September 2, 1921, J. W. C.; one female, Governor's' Bay, New Zealand, November 8, 1922, on grass, J. G. Myers; and one female, Methven, November, 1911. The series is remarkably uniform in size and coloration except for the usual sex differences.
Genus Brachynysius Usinger, nov.
Short, posteriorly broadened; with the pronotum scarcely declivous and the head strongly declivous above as seen from the side; clothed above on pronotum, scutellum and coria with long, erect or backwardly directed hairs. Head as in typical Nysius, transverse, vertex moderately finely, evenly punctate; antenniferous tubercles, only slightly, subacutely produced at exterior angles; bucculae prominent, gradually decreasing in height posteriorly and abruptly ending before posterior margin of head. Antennae as long as head, pronotum and scutellum together, the first segment shortest, third a little longer, and second and fourth segments longest, subequal. Rostrum reaching to posterior coxae, the first segment not attaining base of head. Hemelytra with sides a little dilated and sinuate at base, then strongly dilated and rounded to apex of membrane, strongly convex except for flattened or feebly reflexed emboliar region; clavus and corium entirely opaque with a row of coarse punctures along claval suture and a few coarse punctures at base of emboliar suture; membrane very small, extending beyond level of apices of coria for only one-fourth its total length, without apparent veins. Ostiolar canal extending to about middle of metapleuron, widened or lobate and rounded but not elevated at apex. Posterior margin of metapleuron broadly lamellately produced and feebly reflexed, the postero-lateral angle feebly, subacutely produced. Legs unarmed.
Genotype: Brachynysius convexus Usinger, new species.
Closest to such atypical members of the genus Nysius as huttoni Buch.-White and blackburni Buch.-White, but differing from these as well as all other Orsillini known to me in the geocoroid convexity of the hemelytra and the smooth membrane.
Brachynysius convexus Usinger, new species.
Head a little broader, including eyes, than long, 15: : 11; extending well beyond middle of first antennal segment; eyes a little less than half as wide as vertex. Proportion of antennal segments one to four as 5: 9: 6: 9. Pronotum a little shorter than head on median line, 10: : 12; subtrapezoidal; strongly transverse, being five-sixths as long on median line as broad anteriorly and two-thirds as broad anteriorly as posteriorly; disk elevated, impunctate on broad callosities, narrow anterior margin, broader posterior margin and humeri, elsewhere coarsely punctured, the punctures separated by one or more puncture-widths; lateral margins non-carinate, a little rounded anteriorly and feebly sinuate behind callosities. Scutellum broader than long, 11: : 8, with the usual “Y”-shaped laevigate elevation, elsewhere with a few very coarse punctures. Disk of clavus and corium distinctly coriaceous, very irregularly spotted with dark dots or pseudopunctures on the pale areas.
Colour black with ochraceous apex of clypeus and more or less interrupted median line on head and pronotum, fuscous or lighter posterior lobe of pronotum and humeri, ochraceous tip of scutellum, brown hemelytra with yellowish base and apex of clavus and rather broad yellow areas adjacent to outer and apical margins of corium. Apical margin of corium and membrane, except at extreme apex where it is dark brown, black. Bucculae, rostrum, eyes, antenniferous
tubercles and antennae excepting basal segment brown. Acetabula, a few spots on pleura, apex of ostiolar canal, reflexed posterior margin of metapleuron, and legs, except for pitchy brown femora, brown or lighter.
Size: male, length 2·72 mm., width (hemelytra) 1·33 mm.; female, length 3·16 to 3·33 mm., width (hemelytra) 1·55 to 1·66 mm.
Holotype, male (British Museum), Arthurs Pass, South Island, New Zealand, January, 1923, J. G. Myers. Allotype, female (H. G. Barber), and one female paratype, same data as holotype. The females are considerably paler, with more extensive ochraceous areas on the posterior lobe of the pronotum and on the coria and with the apices of the femora distinctly ochraceous.
Nysius huttoni Buchanan-White.
Nysius huttoni Buch.-White, Ent. Month. Mag., 15: 33, 1879.
This species occurs on Lucerne, and is apparently very common in New Zealand. The eleven specimens before me are so variable in colour and even to some extent in structure that two species may be represented.
The dark form has the corial margins subparallel at base and then distinctly lamellately dilated. The corial disk is mottled with brownish throughout. The membrane is streaked with fuscous and white, giving a criss-cross effect when folded.
A male and a female of this form are at hand from the British Museum, determined by Buchanan-White and collected by J. J. Walker, New Zealand, October, 1901–November, 1902. 1910–384. A male from Ashburton (H. G. Barber Coll.) is faded, but apparently also belongs here.
Other dark specimens differ in that the membrane is marked with black basally, but is entirely clear apically.
Three males of this form were collected at Blenheim on March 13, 1921, on Lucerne (H. G. Barber Coll.), and one female was taken by J. G. Myers on December 13, 1921, at Whangarei.
The pale form has the corium entirely testaceous except for sinuate black markings at the apical margin. The costal margins are less dilated in some specimens. The membrane is clear or more or less cloudy posteriorly. The femora vary from a spotted piceous condition to uniform piceous except at apices.
A male from Whangarei and a male and female from Blenheim are from the same series as recorded above. An additional male is before me from Central Otago, January, 1921, “Linum” (H. G. Barber Coll.).
Rhypodes clavicornis (Fabr.)
Lygaeus clavicornis Fabricius, Ent. Syst., 4: 169, 1794.
Coreus clavicornis Fabricius, Syst. Rhyng., p. 201, 1803 (non Coreus clavicornis Fabricius, Syst. Rhyng., p. 198 = Coreus typhaecornis Fabricius, Syst. Rhyng., Emend.).
Nysius zealandicus Dallas, List of Hemipt. Ins. Brit. Mus., 2: 552, 1852.
Nysius (Rhypodes) zealandicus, Stäl, Hemipt. Fabr., 1: 76, 1868.
Nysius clavicornis, Myers and China, Ann. Mag. Nat. Hist. (10), 1: 380, 1928.
Myersia clavicornis, Evans, Bull. Ent. Res., 19: 353, 1929.
Rhypodes zealandicus, Evans, Bull. Ent. Res., 20: 269, 1929.
An extremely variable species, some specimens of which have the sublateral lobes of the posterior margin of pronotum reduced or
wanting. Sexual differences are greater in this than in many Orsillini, the males being distinctly more slender and parallel-sided than the females. Forty-three specimens are at hand from various localities in both the North and South Islands. The specimens without pronotal lobes are mostly from South Island localities. A single female which is slightly flatter and lighter in colour, but no more so than a teneral specimen from eastern Lake Taupo, New Zealand, is labelled “Australia, Koebele,” but this may very possibly prove to be an error. Dallas (1852) records one specimen as follows: “C. Van Dieman's Land. From Mr. Hooker's Collection.”
A single male determined by W. L. Distant has been received from the British Museum from the collecting of J. J. Walker, October, 1901–November, 1902, 1910–384. Other material includes seventeen specimens in excellent condition sent to me by G. V. Hudson, Paekakariki, New Zealand, May 11, 1938; eight specimens without locality or date (H. G. Barber); and one or two specimens each from the following localities: Whangarei, December 13, 1923 (J. G. Myers); Korokoro, May 7, 1922 (T. Cockroft); Wellington, February 21, 1924 (E. Richardson), and two specimens, October 28, 1922 (J. G. Myers); Lyall B., D. M., January 13, 1922; Ohaupo; Mount Cook, January, 1909; Silverstream, January 14, 1922 (J. G. Myers); Motueka, December 30, 1920 (T. C.); Ashburton; E. L. Taupo, March 7, 1922 (E. H. Atkinson); two specimens, Arthurs Pass, 3000 ft., December 29, 1922, and one specimen, November 13, 1922 (J. G. Myers); Auckland, July 30, 1923 (O. H. Swezey); Wilton's Bush, Wellington, October 28, 1922 (J. G. Myers); two specimens, Otira, December 25, 1920 (T. C.).
Rhypodes sericatus Usinger, new species.
Moderately robust, with sides subparallel, about two-thirds as deep as greatest width and covered with a rather dense, short, silky-white, appressed pubescence throughout as well as some erect hairs on the head, pronotum and scutellum. Disks of head and pronotum very strongly, evenly, arcuately declivous.
Head about one-fourth broader, including eyes, than long, 24: : 19; the anteocular portion longer than an eye, 8: : 7; eyes relatively short and subrounded, scarcely more than one-third the width of interocular space; upper surface scarcely elevated along middle and densely clothed with appressed white hairs except for obliquely, anteriorly placed, subrounded, dull areas between ocelli and inner margins of eyes. Antenniferous tubercles prominent, but their outer angles scarcely or not at all produced. Bucculae prominent anteriorly, gradually reduced at level of antenniferous tubercles, the rostral groove not reaching base of head. Rostrum not reaching hind coxae, the first segment reaching well on to prosternum; proportion of segments one to four as 12: 10: 9: 8. Antennae almost half again as long as greatest width of pronotum, 49: : 34; proportion of segments one to four as 8: 16: 13: 12. Pronotum about two-thirds broader than long, 34: : 20; scarcely longer than head, 20: : 19; and almost half again as broad as head, 34: : 24. Disk moderately convex, the sides roundly depressed and with depressed areas sublaterally on posterior margin and a feeble impression behind callosities; finely
densely pubescent except for narrow sinuous callosities. Scutellum strongly triradiately elevated at middle, forming a rather sharp carina posteriorly. Hemelytra exceeding tip of abdomen by one-seventh the length of the membrane; membrane a little shorter than costal margin of corium and about as long beyond level of apices of coria as in front of this; clavus and corium covered with a short, fine, subappressed pubescence; vein R + M branching just beyond middle; Sc scarcely visible, costal area but little expanded, narrowly exposing connexivum, the costal margins feebly sinuate subbasally, then straight and parallel to slightly beyond level of apex of scutellum beyond which they gradually converge. Under surface distinctly pubescent except on coxal flanges, ostiolar and evaporating areas, and trichobothria bearing areas of abdomen. Posterior margin of metapleuron slightly concave, its lateral angle scarcely rounded.
Colour testaceous marked with fuscous and black above and tinged with ferrugineous beneath. Head black except for ochraceous along inner margins of eyes, apices of antenniferous tubercles and elevated portions of bucculae. Pronotum ochraceous to testaceous with dark fuscous punctures and black humeri (except very narrow margins) and region of callosities. Scutellum largely black with irregular pale areas between the punctures, particularly posteriorly. Clavus and corium testaceous with fuscous irregularly along inner margin and along commissure of clavus, irregular and faintly on vein Cu and irregularly but darkly along vein R + M and between this and costal margin except for broad, subapical, pale area. Apical margin of corium dark near apex and at joining of veins Cu and M. Membrane whitish with irregular fuscous spots, especially along middle. Narrowly exposed connexivum black with pale margins and sutures between segments. Under surface pale, with black sterna and black at middle of pleural disks and irregularly black-spotted abdomen basally at middle. Rostrum black on apical half. Antennae infuscated, dark brown to black with irregular ochraceous basally on first segment and at middle of second and apical three-fourths of third segments. Legs ochraceous with distinct black spots below and broad black areas above on femora and less distinct spots on tibiae and with apices of tibiae and tarsi infuscated.
Size: male, length 5·33 mm.; width (connexivum) 2 mm.
Holotype: male, Terawhiti, North Island, New Zealand, April 23, 1922, I. H. W. (H. G. Barber Coll.) and two paratypes: one, same data as type, and the other, on Cassinia, Terawhiti, April 23, 1933, I. H. W.
This species at first suggests an Ortholomus because of the feebly expanded costal margins, but, upon closer study, it is seen to have nothing to do with that Holarctic genus. Closest affinities are with other Rhypodes, from which it may be distinguished by its sub-parallel sides and subequal apical antennal segments.
Rhypodes myersi Usinger, new species.
Broad, subflattened, a little more than half as deep as greatest width at connexivum, 28: : 48, covered in great part with a moderately dense, subappressed, white pubescence and with erect hairs on pronotal and scutellar disks.
Head a little broader, including eyes, than long, 26: : 24; densely clothed with recumbent white hairs except for narrow, anteriorly divergent stripes from ocelli to inner anterior margins of eyes; outer angles of antenniferous tubercles· slightly but distinctly, subacutely produced; bucculae strongly elevated anteriorly, abruptly and then gradually decreasing in height to level of anterior margins of eyes, the buccal groove continuing as a smooth black trough almost to posterior margin of head. Eyes small, not touching antero-lateral angles of pronotum, the head being a little exserted and the inner margins of the eyes rounded outward away from this point; width of an eye one-third the width of interocular space. Antennae short and thick; as long as head, pronotum, and half of scutellum; first segment very stout; second and third more slender, almost cylindrical; second segment almost as thick as front tibiae basally; fourth segment thickened and fusiform; proportion of segments one to four as 9: 19: 13: 17. Rostrum slightly surpassing posterior coxae; first segment not quite reaching base of head; proportion of segments one to four as 16: 16: 17: 13. Pronotum only slightly declivous; longer than head on median line, 26: 21; three-eighths broader behind than long; one-half as wide at extreme anterior margin as at posterior margin, three-fourths as wide at level of callosities; lateral margins distinctly sinuate; posterior margin feebly, roundly, lamellately produced sublaterally; disk subflattened, irregularly covered with black punctures spaced from one to three puncture widths apart, except on slightly elevated callosities and humeri and along a median longitudinal line; callosities sinuate, bent anteriorly and then laterally on outer halves. Scutellum a little broader than long, 24: : 19. Hemelytra long, distinctly surpassing tip of abdomen, the membrane complete; lateral margins of corium slightly, evenly arcuate throughout their length, slightly exposing connexivum; claval suture with a very inconspicuous row of punctures on inner side near base; emboliar suture, seen from the side, also with some inconspicuous punctures: corium subhyaline; membrane rather clear, venation typical of Nysins. Ostiolar canal well developed, reaching to about middle of metapleuron, the apical lobe quite large, rounded and somewhat elevated; canal surrounded on metapleural and adjacent mesopleural regions by naked, dull, black areas. Posterior margin of metapleuron shining, produced as a broad lamella which is moderately reflexed; postero-lateral angles very broadly subrounded. Fourth visible abdominal segment, in the female, short but not concealed at middle, its posterior margin moderately angulately emarginate. Legs simple, the femora unarmed. Tibiae somewhat enlarged apically.
Colour black with ochraceous to whitish as follows: on apices of second and third antennal segments; pronotum excepting broad, black elevations at callosities, black discal punctures, and brown longitudinal lines either side of middle; median longitudinal line on scutellum except at extreme base; clavus except along commissure; corium except for faintly embrowned veins and dark brown vitta at middle of apical margin extending on to membrane; bucculae; anterior margin of prosternum and posterior margins of propleura;
folds of ostiolar canal but not apical lobe; lamellate posterior margins of metapleura; coxal flanges, inner parts of coxae, trochanters, variegated portions of femora between black spots, middle of tibiae, and bases of tarsi; narrow connexival margins above and beneath; and paired, sublateral glandular spots, two longitudinal vittae on middle of either side, and middle of segments behind third visible segment of abdomen beneath. Membrane a little clouded, subhyaline, with a distinct brown vitta at middle of base on either side becoming faint just beyond junction of interior veins but continuing obscurely to beyond middle of membrane.
Size: male, length 6·5 mm., width (connexivum) 2·3 mm.; female, length 7·5 mm., width (connexivum) 2·6 mm.
Holotype: female (H. G. Barber Coll.) Arthurs Pass, South Island, New Zealand, 3500 feet, December 22, 1922, J. G. Myers collector. Allotype, male (H. G. Barber Coll), and three female paratypes, same data as holotype. One male paratype, same locality as holotype, but taken on November 16, 1922. One male and one female paratype, Wakatipu, January 1, 1921, G. V. Hudson.
The specimens collected by Hudson are darker in colour with distinct, sublateral brown vittae on the pronotum, brownish veins and mottled areas on the clavus and corium, and black middle and hind femora with pale apices. The male collected at Arthurs Pass in November is considerably smaller than the other specimens, but otherwise typical.
Named in honour of Dr. J. G. Myers, the versatile Hemipterist, to whom we owe most of our. New Zealand material in the Orsillini.
Myersi is not closely allied to any other Orsilline Lygaeid known to me. Its broad form, exserted head, and short bucculae are suggestive of Nysius californicus, a species with a more declivous pronotum, more slender antennae, shorter vestiture, basally dilated costal margins, and a shorter, medially concealed fourth ventral segment in the female. The true allies of myersi are doubtless to be found among New Zealand forms not yet discovered. Certainly it is abundantly distinct from any of the New Zealand species known to me at present. The subflattened form and flattened, laterally sinuate pronotum impart a superficially different facies to this species which tempts one to separate it generically. However, many allied forms may yet be found which may further elucidate its proper placement, so it is referred to the composite, primitive genus Rhypodes for the present.
Rhypodes chinai Usinger, new species.
Robust, moderately large, less than twice as broad across hemelytra as greatest depth at thorax, 35: : 20; body surface polished, covered with a short, white pubescence which is rather dense and appressed except on posterior lobe of pronotum. Pronotal and scutellar disks with an additional vestiture of erect, fulvous hairs which are best seen from the side. Head and pronotum quite strongly declivous.
Head, including eyes, broader than long, 21: : 18; interocular space a little more than twice as wide as an eye, 11: : 5, with a small, polished, bare area in front of each ocellus; not strongly produced before the eyes, the distance from front margins of eyes to apex of
head subequal to distance to base of head from the same point outer angles of antenniferous tubercles scarcely, roundly produced. Bucculae prominently elevated anteriorly, then abruptly decreasing in height to just behind level of antenniferous tubercles, not reaching base of head. Rostrum reaching to hind margins of posterior coxae, the proportion of segments one to four as 12: 12: 11: 6. Antennae almost as long as head, pronotum, and scutellum together; slender, the second segment not as thick as front tibiae basally; proportion of segments one to four as 7: 16: 10: 12; first segment except at narrowed base and middle of fusiform fourth segment about equally thick, second and third segments more slender. Pronotum as long as head on median line, a little narrower at extreme apex than long, 16: : 18; rather regularly widening posteriorly, the width at humeral angles a little less than twice anterior width, 29: : 16; lateral margins feebly, roundly swollen at level of callosities, a little sinuate behind this; posterior margin sublaterally depressed, faintly rugose, and feebly lamellately produced posteriorly over bases of clavi; disk a little convex, without lateral carinae, the rather dense punctures in irregular transverse rows less than one puncture width apart, the rows one or more puncture widths apart; feebly but distinctly depressed along posterior margins of naked, laterally sinuate callosities; a median, longitudinal, posteriorly irregular, impunctate line. Scutellum a little broader than long, 17: : 14, the “Y”-shaped, elevation very prominent; sides carinately elevated; apex subacute. Hemelytra very long, the membrane exceeding tip of abdomen by more than one-third its length; clavus and corium opaque, superficially minutely punctured throughout, the claval and emboliarsutures without conspicuous rows of punctures; costal region with an extra vein on apical half very prominent, closely paralleling-forked emboliar vein; costal margins subparallel for two-thirds the length of scutellum, then gradually roundly dilated, slightly converging posteriorly, completely covering the connexivum. Ostiolar canal extending over half the distance to lateral margin of metapleuron, the apical lobe prominent, raised, and rounded at apex. Posterior margin of metapleuron broadly reflexed, a little concave, the postero-lateral angle not at all produced, rounded. Posterior margins of fourth and fifth abdominal segments below, in the female, deeply, angulately emarginate, concealed beneath third visible segment at middle.
Colour black with testaceous to white on the following: inner margins of eyes; pronotal disk longitudinally at middle, on anterior margin, and more or less on posterior half except for black humeral angles, black punctures, and broad longitudinal, ill-defined, fulvous, fasciae either side of middle; apical median longitudinal elevation of scutellum; clavus except for a few scattered fuscous spots; corium except black apex and fuscous lateral margin on apical half and broad, transverse, subapical fuscous area; acetabula, trochanters, bases and apices of femora, middle of tibiae, and bases of tarsi; extreme apices of second and third antennal segments; and venter sublaterally on posterior half. Membrane pale and hyaline with more or less extensive fuscous between the veins, with a large, round,
black spot at base of membrane, another, more elongate and sub-triangular, on either side opposite corial cell formed by forked emboliar vein.
Size: male, length 5·65 mm., width (hemelytra) 2 mm.; female, length 5·94 mm., width (hemelytra) 2·17 mm.
Holotype, male (British Museum) and five male paratypes, Mount Matthews, 3000 feet, September 25, 1921. Allotype, female (H. G. Barber Coll.) and one female paratype, Arthurs Pass, 3800 feet, December 26, 1922, J. G. Myers collector.
There is considerable colour variation in the paratypes, one male in particular, being much darker, almost entirely fuscous on the clavus and corium, the membrane generally infuscated, with white veins.
Perhaps closest to myersi, but entirely differently shaped, with more slender antennae, concealed middle of angulately emarginate fourth abdominal segment in the female, and different colour pattern.
Rhypodes stewartensis Usinger, new species.
Very broad and robust, shining, and clothed with a short, appressed, white pubescence and with erect hairs, as well, on the pronotum and scutellum.
Head less than one-third broader than long, 23: : 18½; anteocular portion longer than an eye, 8: : 6½; eyes short and sub-rounded, about one-third the width of interocular space, 4½: : 14; tylus very broad at apex and juga relatively well developed and slightly expanded at sides; antenniferous tubercles briefly but distinctly produced laterally. Upper surface densely clothed, with appressed white hairs except for subrounded glabrous areas between ocelli and inner margins of eyes. Bucculae distinct anteriorly but very short, abruptly reduced at level of antenniferous tubercles, the rostral groove not reaching base of head. Rostrum reaching about to apices of middle coxae, the first segment extending well on to prosternum; proportion of segments one to three as 12: 10: 8 (last segment obscured). Antennae one-third longer than greatest width of pronotum, 47: : 36; proportion of segments one to four as 8: 14: 11: 14. Pronotum moderately convex, being slightly elevated anteriorly, rounded at sides, and scarcely depressed sublaterally along posterior margin; sides broadly and feebly convex anteriorly at level of callosities, slightly sinuate behind this and broadly rounded at humeri, the humeral disk impunctate, clothed with appressed hairs particularly around callosities, and with sparser, much longer, erect hairs. Hemelytra scarcely exceeding tip of abdomen, the membrane distinctly shorter than costal margin of corium and about as long behind level of apices of coria as in front of this; corial veins, including Sc, distinct; vein R + M without a distinct inner branch, M. Costal margins feebly sinuate subbasally, then subparallel to level of apical third of scutellum beyond which they are moderately arcuate. Connexivum narrowly exposed. Under surface in great part pubescent. Posterior margin of metapleuron slightly concave, the lateral angle scarcely produced, subrounded. Female genital cleft very short, not reaching to middle of venter, the fourth ventral segment a little over half as long as third, and fifth a little less than half as long as fourth at middle.
Colour brownish to ochraceous marked with black. Head black with ochraceous along inner margins of eyes at apex of tylus and on elevated portions of bucculae. Pronotum ochraceous with black callosities and punctures and brown along posterior margin on either side of the middle, extending across humeri which have narrowly yellowish hind margins. Disk also dark brown at centre behind callosities. Scutellum almost entirely dark brown to black except for ochraceous apical carina. Clavus and corium ochraceous irregularly but generally covered with pitchy brown over a large portion of clavus and over corium except basally and subapically, the apical margin of corium dark brown to black apically and between inner angle and joining of vein Cu. Membrane clear hyaline except for distinct piceous area on either side at middle of apical margin of corium. Connexivum alternated, being black, with white at sutures of segments. Under-surface dark brown to black, with paler glabrous coxal flanges and with the venter variegated, especially posteriorly. Rostrum piceous, antennae black with the joints between segments somewhat paler and with the last segment brownish. Legs brownish, the coxae ochraceous apically. Femora black spotted beneath and entirely black above, with ochraceous apices, tibiae black subbasally and apically, and tarsi infuscated apically.
Size: male, length 5·05 mm., width (hemelytra) 2 mm.; female, length, 5·22 mm., width (hemelytra) 2·22 mm.
Holotype, female (British Muscum), Stewart Island, 1926 (Harris) and allotype, male, same data, in my collection.
Perhaps closest to chinai, from which it differs in its more robust form, shorter rostrum, and shorter female genital cleft. The male is very much darker, but is not in perfect condition, so this may not be a natural situation.
A female is before me from Lyttelton, New Zealand, October, 1901, to November, 1902, J. J. Walker, and a male from Mount Cook, January, 1909, which are very close to stewartensis, differing only in the presence of a distinct branch of R + M. Whether these prove to be the same or a distinct species will depend upon further material in better condition.
Dallas, W. S., 1852. List of the specimens of Hemipterous insects in the collection of the British Museum, London, part II, pp. 369–592, 4 plates.
Evans, J. W., 1929a. A new species of Nysius from Australia, Bull. Ent. Res., 19: 351–354, 3 figs.
—– 1929b. New species of Nysius from South Africa. Bull. Ent. Res., 20: 267–270, fig. 1.
Fabricius, J. C., 1794. Entomologia Systematica, Hafniae, Tom. IV, 472 pp.
—– 1803. Systema Rhyngotorum, Brunsvigae, x + 314 pp., Emendanda et Index Alphabeticus.
Myers, J. G., and China, W. E., 1928. A list of New Zealand Heteroptera with the description of a remarkable green Aradid representing a new genus, Ann. Mag. Nat. Hist. (10), 1: 377–394, 2 figs.
Stal, C., 1868. Hemiptera Fabriciana, 1. Kongl. Svenska Vet.-Akad. Hand., Band 7, no. 11, pp. 1–148.
Usinger, R. L., 1941. The genus Nysius and its allies in the Hawaiian Islands, B. P. Bishop Museum Bulletin 173 (in press).
White, F. Buchanan, 1878. List of the Hemiptera of New Zealand, Ent. Month. Mag., 15: 31–34.