Plagiognathus, FIEBER, 1858

SCHUH, RANDALL T., 2001, Revision Of New World Plagiognathus Fieber, With Comments On The Palearctic Fauna And The Description Of A New Genus (Heteroptera: Miridae: Phylinae), Bulletin of the American Museum of Natural History 2001 (266), pp. 1-267 : 8-17

PLAGIOGNATHUS FIEBER

Plagiognathus Fieber, 1858: 320 (n. gen.). Type species: Lygaeus arbustorum Fabricius, 1794 . Fixed by subsequent designation.

Microphylellus Reuter, 1909: 76 (n. gen.). Type species: Microphylellus modestus Reuter, 1909 . NEW SYNONYMY.

Gerhardiella Poppius, 1911: 84 (n. gen.). Type species: Gerhardiella rubida Poppius, 1911 (syn. by Carvalho, 1952: 65).

Plagiognathus (Parapsallus) Wagner, 1952: 187 (n. subgen.). Type species: Capsus vitellinus Scholtz, 1847 . REVISED SYNONYMY.

Chaetophylidea Knight, 1968: 33 (n. gen.). Type species: Plagiognathus moerens Reuter, 1909 . NEW SYNONYMY.

DIAGNOSIS: Distinguished by the form of the male genitalia with twisted vesica, two terminal blades, a narrow to broad ‘‘flange’’, and lanceolate right paramere (fig. 25: grandis ). Appearance similar to Europiella species , but head usually more strongly projecting anteriorly and left paramere never ‘‘bifid’’ apically as in that group. Vesica in Europiella sometimes with two elongate, flattened apical blades as in Plagiognathus , but those uniquely modified in many species. Antennal segment 2 never sexually dimorphic, always slender and weakly tapered toward base in both sexes. Vestiture always with simple setae, sometimes intermixed with weakly to strongly flattened setae.

REDESCRIPTION: Elongate, more or less parallel­sided; total size ranging from very small to moderately large, range total length 2.33– 5.75, range length apex clypeus–cuneal fracture 1.81–3.93. COLORATION: Frequently dark, castaneous to nearly black, sometimes with pale areas forming a more­or­less tesselate pattern, or one of linear striping; overall coloration sometimes orange, red, or al­ most entirely pale; antennae ranging from totally black to totally pale, segment 2 not infrequently dark proximally and pale distally; tibiae usually with pale background coloration, tibial spines commonly with dark spots at bases (fig. 1H) contrasting with tibial background coloration, tibiae sometimes entirely pale without dark spots at bases of spines (fig. 1G) or weakly to heavily darkened over entire surface. SURFACE AND VESTITURE: Impunctate, smooth, dull to moderately shining; vestiture always with at least some simple pale or dark setae, sometimes also with woolly, sericeous setae, often shining, silvery, or golden in appearance, and rarely with flattened scalelike setae appressed to body surface, as in physocarpi (fig. 36B– E). STRUCTURE: Head declivent, usually at least weakly projecting beyond anterior margin of eyes, clypeus visible from above or not; antennae relatively long, segment 2 usually as long as width of head across eyes (sometimes much longer), slender, with no obvious sexual dimorphism; labium reaching from near apex of middle coxae to well onto abdomen; claws slender, weakly and evenly curving, pulvillus relatively small, flaplike, and subbasal on claw; parempodia setiform. Abdomen relatively broad basally and tapering toward apex; genital capsule relatively large, conical. MALE GENITALIA: Vesica sigmoid, with one­half twist; two terminal blades at apex of vesica, the anterior blade usually longer than posterior; secondary gonopore ovoid, subtending terminal blades; straps of vesica contiguous with terminal blades; vesica often with a ‘‘flange’’ subtending secondary gonopore (figs. 20, 22, 29, fl). Left paramere boat­shaped (fig. 25: grandis ); right paramere lanceolate (fig. 25: grandis ); phallotheca rather sharply curving, attenuated apically, and without distinctive ornamentation (fig. 25: grandis ).

DISCUSSION: The form of the male genitalia, while similar to that of some other phylines, appears to offer the most consistent character indicating the monophyly of Plagiognathus . Important attributes include: the sigmoid vesica; the half­twist of the body of the vesica; the form of the two apical blades; the position and form of the secondary gonopore; and the frequent presence of a narrow to broad flange (see figs. 20–33). Although the structure of the vesica is not invariate throughout the group, it nonetheless seems preferable at this point to define Plagiognathus in a more inclusive fashion, rather than producing a number of poorly characterized segregate genera.

Flattened apical vesical spines of a structure similar to that found in Plagiognathus also occur in the sympatric genus Europiella Reuter (fig. 1A, B) and also in Phyllopidea Knight from western North America (fig. 1C, D). The largely Southern Hemisphere group Campylomma Reuter also has paired apical spines of a similar structure to those found in Plagiognathus (e.g., see Schuh, 1984), but the vesica is not characteristically twisted as in Plagiognathus and always lacks the flange found in most Plagiognathus spp. The placement and structure of the secondary gonopore is somewhat different in Europiella than in Plagiognathus . Furthermore, the right paramere is lanceolate in Plagiognathus (fig. 25), whereas it is broadened apically in Europiella and has two ‘‘tips’’ or ‘‘points’’ (fig. 1A, B). The apical spines are shorter in Phyllopidea (fig. 1C, D) than in most Plagiognathus species ; furthermore, the head in Phyllopidea is much more strongly dorsoventral in orientation than in Plagiognathus , and the dorsal vestiture is composed of suberect, black, bristlelike setae, a feature seen only in a few Nearctic Plagiognathus spp. Phyllopidea spp. , like most Europiella spp. , feed on Artemisia spp. ; no Nearctic Plagiognathus species feed on Artemisia , although several are known to feed on other members of the Asteraceae ; only two Palearctic species, amurensis Reuter and yomogi Miyamoto , appear to consistently feed on Artemisia .

The placement by Knight (1923) of several North American phyline species in Psallus Fieber —on the basis of their possessing flattened appressed setae—cannot be justified when male genitalic structure is also considered. The vesica of Psallus falleni Reuter (fig. 1E) illustrates the typical ‘‘spined’’, ‘‘toothed’’, or otherwise ornamented apical portion of the vesica, a feature found in all Psallus sensu stricto species, but dissimilar to the vesical structure of Plagiognathus arbustorum and its congeners. No true Psallus species are restricted to North America, and those species that do occur there all appear to be truly Holarctic or introduced (Wheeler and Henry, 1992). Psallus sensu Knight is a polyphyletic group. Many North American phyline species originally placed in Psallus belong to Plagiognathus , and most of the rest belong to Oligotylus Van Duzee (Schuh, 1999) . Whereas Psallus is extremely speciose in the Palearctic, species diversity in Plagiognathus is greatest in the Nearctic.

Microphylellus Reuter was diagnosed on the basis of the pale tibial coloration, whereas species placed in Plagiognathus had tibial spines with dark spots at their bases. The male genitalia of Microphylellus modestus Reuter , the type of the genus (fig. 27), are of the typical Plagiognathus type, and I therefore treat Microphylellus as a junior synonym of Plagiognathus ; the only feature not ‘‘typical’’ of Plagiognathus in the classic sense is the pale tibiae. I transfer several additional species from Microphylellus to Plagiognathus , including some species that feed on conifers, even though the structure of their genitalia varies somewhat from that of arbustorum (fig. 21) and a great number of the native North American species. A limited number of species currently placed in Microphylellus are not congeneric with the type and belong to other genera. They are dealt with at the end of the present paper.

Knight (1968) erected the genus Chaetophylidea to receive Plagiognathus moerens Reuter. He noted that the general structure, including the pretarsus, was like that of Plagiognathus species , but that the vestiture, particularly on the head and pronotum, was bristlelike. The genitalia of moerens are of the Plagiognathus type (fig. 28). I am therefore treating Chaetophylidea as a junior synonym of Plagiognathus .

Wagner ( 1952) described the subgenus Psallus (Parapsallus) designating Capsus vitellinus Scholtz as the type. Since that time the status of vitellinus has shifted, with Parapsallus having been treated as part of Psallus , or Plagiognathus , or elevated to generic rank. In the present paper vitellinus is treated as a Plagiognathus species , because it has male genitalia of the Plagiognathus type (fig. 33), and most of its other characteristics fall within the range of variation seen in Plagiognathus as construed herein; Parapsallus is therefore treated as a junior synonym of Plagiognathus .

Wagner ( 1949) described the subgenus Poliopterus to accommodate some European phylines known to feed primarily on Artemisia spp. Schuh et al. (1995) pointed out that two of the species placed in Poliopterus by Wagner were treated as Europiella spp. by North American workers. Schuh et al. (1995) treated Poliopterus as a junior synonym of Europiella , thus making the latter group monophyletic. The species that Wagner ( 1949) placed in Poliopterus share some features with Plagiognathus (in the sense of arbustorum , the type). These include: the presence of two large apical spines on the vesica in most species; the pretarsus having elongate, slender, gently curving claws with a small subbasal pulvillus; similarities in structure of the scent gland evaporatory area (e.g., figs. 2B, 3B, 4C); and the metathoracic spiracle being sunken and generally having ‘‘mushroom bodies’’ only dorsad of it in a narrow line. In spite of these similarities, there is no evidence suggesting that Plagiognathus becomes paraphyletic if the Europiella species are not included. Indeed, both groups possess unique genitalic features.

CHECKLIST OF SPECIES­ GROUP NAMES PROPOSED IN OR CURRENTLY USED IN PLAGIOGNATHUS FIEBER

Because of the large number of available names treated as junior synonyms, the large number of new synonyms, and the large number of new combinations presented in this paper, I am including the following checklist of names used in Plagiognathus . The checklist will serve to update information presented in the most recent world catalog of the Miridae (Schuh, 1995) . A few taxa that have previously been placed in Plagiognathus , but were described in other genera and are removed from Plagiognathus in the present paper, are not included; their disposition will be found in the final section of the paper. Valid species in Plagiognathus are listed in boldface, junior synonyms are underlined, and species placed in other genera or incertae sedis are in italics. For species not originally described in Plagiognathus , the genus of original description is indicated in parentheses.

abrotani Wagner, 1949 = Europiella decolor

(Uhler) alashanensis Qi and Nonnaizab, 1993 albatus (Van Duzee, 1915) (Psallus) albella Stichel, 1934 = Europiella albipennis

(Fallen) albellus Knight, 1953 (preoccupied) = Americo­

dema knighti (Kerzhner and Schuh) albicans Reuter, 1901 = bipunctatus Reuter albifacies Knight, 1927 albocuneatus Knight, 1923 = obscurus Uhler albonotatus Knight, 1923 = fuscosus (Provanch­

er) alboradialis Knight, 1923 albus Reuter, 1894 alnicenatus (Knight, 1923) (Psallus) alpina Reuter, 1875, see Europiella Reuter alyssi Pushkov, 1959 = Lepidargyrus syriacus

(Wagner) amorphae (Knight, 1930) (Psallus) amurensis Reuter, 1883 amygdali (Linnavuori, 1965), see Heterochlorillus

Putshkov annulatus Stichel, 1934 = fulvipennis (Kirsh­

baum) (junior primary homonym) annulatus Uhler, 1895 annulicornis Reuter, 1879, see Badezorus Distant antennaria Stichel, 1934 = Europiella artemisiae

(Becker) apicatus Knight, 1923 = albatus (Van Duzee) aquilinus, new species arbustorum (Fabricius, 1794) arenicola Wagner, 1941 = Europiella albipennis

(Fallen) assmanni Stichel, 1934 = Europiella artemisiae

(Becker) astericola (Knight, 1930) (Psallus) atricornis Knight, 1926 beckeri Stichel, 1934 = Europiella albipennis

(Fallen) biplagiatus Stichel, 1958 = chrysanthemi (Wolff) bipunctatus Stichel, 1934 = chrysanthemi (Wolff)

(junior primary homonym) bipunctatus Reuter, 1883 blatchleyi Reuter, 1912 breviceps Reuter, 1878, see Eumecotarsus Ker­

zhner brevirostris Knight, 1923 brunneus (Provancher, 1872 ( Lygus ) brunnipennis Meyer­Dur, 1843 = arbustorum (Fa­

bricius) canoflavida Qi and Nonnaizab, 1993, see Euro­

piella Reuter carinatus Knight, 1926 = dispar Knight carneolus Knight, 1927, see Pinophylus Schwartz

and Schuh, 2000 caryae Knight, 1923 = albatus (Van Duzee) chloromelas (Gmelin, 1790) ( Cimex ) = arbusto­

rum (Fabricius) chrysanthemi (Wolff, 1804) (Miris) cibbetsi, new species cinerascens Reuter, 1904 = chrysanthemi (Wolff) circumcinctus Stichel, 1934 = fulvipennis

(Kirschbaum) collaris (Matsumura, 1911) (Chlamydatus) collinus Wagner, 1941 = Europiella albipennis

(Fallen) compar Knight, 1923 = fuscosus (Provancher) concinna Reuter, 1875, see Tuponia Reuter concoloris, new species confusus Reuter, 1909 , incertae sedis cornicola Knight, 1923 crataegi Knight, 1929 = dispar Knight crocinus Knight, 1927 , incertae sedis cruralis Van Duzee, 1917 , see Tuxedo , new genus cunctator Horvath, 1887 = chrysanthemi (Wolff) cuneatus Knight, 1923 = obscurus Uhler davisi Knight, 1923 debilis Blatchley, 1926 = tinctus Knight decolor Lindberg, 1934 = Psallus haematodes

(Gmelin) delicatus (Uhler, 1887) (Psallus) depallens Knight, 1929 = salicicola Knight dimorphus, new species dispar Knight, 1923 diversicornis Reuter, 1899 = fulvipennis (Kirsch­

baum) diversus Van Duzee, 1917 = Europiella artemi­

siae (Becker) elongatus (Knight, 1923) (Microphylellus) = fla­

vipes (Provancher) emarginatae, new species extrema Reuter, 1901 = Europiella decolor (Uhl­

er) fasciatus Jakovlev, 1893 = Psallus haematodes

(Gmelin) femoralis (Geoffroy, 1785) ( Cimex ) = chrysan­

themi (Wolff) femorepunctatus (Goeze, 1778) ( Cimex ) = chyr­

santhemi (Wolff) fenderi, new species fennicus Wagner = 1961, vitellinus (Scholtz) flaveolus Knight, 1923 = politus Uhler flavescens Knight, 1925 = longipennis (Uhler) flavicornis Stichel, 1958 = fulvipennis (Kirsch­

baum) (junior primary of homonym) flavicornis Knight, 1923 flavidus Knight, 1929 flavipes (Provancher, 1872) (Capsus) flavipes Reuter, 1875 (preoccupied) = Plagiog­

nathus reuterellus Schuh , new name flavoscutellatus Knight, 1923 flavus Knight, 1964 fraternus Uhler, 1895 = brunneus (Provancher) fulvaceus Knight, 1964

fulvidus Knight, 1923 fulvipennis (Kirschbaum, 1856) (Capsus) fulvotinctus Knight, 1929 = negundinis Knight fumidus (Uhler, 1895) (Agalliastes) = Europiella

decolor (Uhler) furvus Knight, 1927 = albatus (Van Duzee) fusciflavus Knight, 1929 = verticalis Uhler fusciloris Reuter, 1878 fuscipes Knight, 1929 fuscosus (Provancher), 1872 ( Lygus ) fuscotibialis Knight, 1964 = brunneus (Provanch­

er) geminatus Knight, 1929, see Cariniocoris Henry geranii Knight, 1964 = shoshonea Knight gilva Kulik, 1965 = Europiella livida (Reuter) gleditsiae Knight, 1929 = Atractotomus griseolus

(Reuter) gracilis Wagner, 1956 = Europiella artemisiae

(Becker) grandis Reuter, 1876 guttatipes (Uhler), 1895 ( Lygus ) hallucinatus, new species herbaalbae Wagner, 1969, see Europiella Reuter hortensis (Meyer­Dur, 1843) ( Capsus ) = arbus­

torum (Fabricius) ilicis Knight, 1925, see Cariniocoris Henry infuscata (Fieber, 1861), see Icodema Reuter inopinus Knight, 1926 = albatus (Van Duzee) intrusus Knight, 1926 = brevirostris Knight kiritshenkoi Kulik, 1975, see Europiella Reuter larae Kerzhner, 1978 = Europiella decolor (Uhl­

er) laricicola Knight, 1923 lattini, new species leucopus Kerzhner, 1979, see Europiella Reuter lineatus Van Duzee, 1917 litoralis Wagner, 1949 = Europiella decolor (Uhl­

er) livida Reuter, 1906 , see Europiella Reuter lividella Kerzhner, 1979, see Europiella Reuter longipennis (Uhler, 1895) (Oncotylus) longirostris (Knight, 1923) (Microphylellus) lonicerae, new species louisianus, new species lugubris (Hahn, 1835) ( Phytocoris ) = arbustorum

(Fabricius) luteus Knight, 1929 maculatus Stichel, 1934 = chrysanthemi (Wolff) maculipennis (Knight, 1923) (Microphylellus) maculosus Zhao, 1996 major Reuter, 1875 = Psallus ocularis (Mulsant

and Rey) mamorae Lindberg, 1940 = Lepidargyrus lividus

(Reuter) medicagus Arrand, 1958 = brunneus (Provanch­

er) melliferae, new species mexicanus, new species miyamotoi Kerzhner, 1988, see Europiella Reuter modestus (Reuter, 1909) (Microphylellus) moerens Reuter, 1909 moesta Reuter, 1906, see Europiella Reuter monardellae, new species morrisoni (Knight, 1923) (Psallus) mundus Van Duzee, 1917 negundinis Knight, 1929 nicholi (Knight, 1964) (Psallus) , see Reuterosco­

pus Kirkaldy nigrescens Stichel, 1934 = Europiella alpina

Reuter nigricornis Hsiao, 1963 = amurensis Reuter nigritibialis Knight, 1964 = nigronitens Knight nigritus Knight, 1923 = brevirostris Knight nigrocunealis Putshkov, 1975, see Europiella

Reuter nigrofemoratus Knight, 1923 = obscurus Uhler nigrofuscus Stichel, 1934 = arbustorum (Fabri­

cius) nigrolineata Knight, 1923, see Americodema

Henry, 1999 nigronitens Knight, 1923 nokhurensis Putshkov, 1976 , incertae sedis notodysmicos, new species nubilis Knight, 1923 = blatchleyi Reuter obscura Sahlberg, 1920 (preoccupied) = Euro­

piella artemisiae (Becker) obscuriceps (Stal, 1858) (Eurymerocoris) obscurus Uhler, 1872 occipitalis Reuter, 1908 , incertae sedis olivaceus Reuter, 1880 oshensis Putshkov, 1976 = arbustorum (Fabri­

cius) ovatula Wagner, 1952, see Europiella Reuter paddocki Knight, 1964 , incertae sedis pallescens Zheng and Li, 1991 pallidicornis Knight, 1923 = fuscosus (Provanch­

er) pallidipennis Reuter, 1906 = collaris Matsumura

(junior primary homonym) pallidipennis Sahlberg, 1868 = Plesiodema pine­

tella (Zetterstedt) pallidus Reuter, 1900 paramundus, new species parshleyi (Knight, 1923) (Psallus) pemptos, new species pesvariegatus (Goeze, 1778) ( Cimex ) = arbusto­

rum (Fabricius) phaceliae, new species phlomidis Lindberg, 1934, see Malacotes Reuter phoradendronae Knight, 1929 , incertae sedis physocarpi (Henry, 1981) (Psallus) piceicola, new species picticornis Horvath, 1898 = bipunctatus Reuter pictipes (Van Duzee, 1918) ( Psallus ), see Megal­

opsallus Knight pini Vinokurov, 1978

plagiathus Reuter, 1876 plessaeus (Geoffroy, 1785) ( Cimex ) = arbustorum

(Fabricius) pluto Van Duzee, 1917 , incertae sedis polhemorum, new species politus Uhler, 1895 punctatipes Knight, 1923 puncticeps Reuter, 1876 = Chlorillus pictus (Fie­

ber) putonii Reuter, 1875 = Monosynamma bohemanni

(Fallen) raphani Wagner, 1963 reinhardi Johnston, 1935 , incertae sedis repetitus Knight, 1923 repletus Knight, 1923 = albatus (Van Duzee) retovskii Reuter, 1885 = Zophocnemis bicolor

(Jakovlev) reuterellus Schuh , new name for flavipes Reuter reuteri Westhoff, 1881 = arbustorum (Fabricius) ribesi Kelton, 1982 rideri, new species rileyi, new species rosicola Knight, 1923 rosicoloides, new species rubidus (Poppius, 1911) (Gerhardiella) = grandis

Reuter rubricans Provancher, 1887, see Rhinocapsus

Uhler rufinervis Jakovlev, 1880, see Sacculifer Kerzhner salicicola Knight, 1929 salviae Knight, 1968 servadeii Wagner, 1972 = Europiella artemisiae

(Becker) schaffneri, new species shepherdiae Knight, 1929 shoshonea Knight, 1964 similatus Henry and Wheeler, 1988 (unnecessary

new name; proposed in error) similis Knight, 1923 = albatus (Van Duzee) simplex Stichel, 1956 = Europiella alpina Reuter solani Matsumura, 1917 = Europiella artemisiae

(Becker) spilotus Fieber, 1858, see Parachlorillus Wagner stitti Knight, 1964 strawinskii Sienkiewicz, 1986, see Europiella

Reuter strigifemur Wagner, 1964, see Europiella Reuter subovatus Knight, 1929 suffuscipennis Knight, 1923 symphoricarpi (Knight, 1968) (Microphylellus) =

fulvaceus Knight syrticolae Knight, 1941 tamaninii Carapezza, 1998 tenellus Knight, 1929 texanus, new species tiliae Knight, 1926 = Plesiodema sericea (Hei­

demann) tinctus Knight, 1923

tomentosa Reuter, 1888, see Europiella Reuter tsugae (Knight, 1923) (Microphylellus) tumidifrons (Knight, 1923) (Microphylellus) unimaculatus Stichel, 1956 = Parachlorillus spi­

lotus (Fieber) urticae Knight, 1964 vaulogeri Reuter, 1895 verticalis (Uhler, 1894) (Macrotylus) vicarius Reuter, 1891 = chrysanthemi (Wolff) viridescens (Gmelin, 1790) ( Cimex ) = chrysan­

themi (Wolff) viridulus (Fallen), 1807) ( Lygaeus ) = chrysan­

themi (Wolff) vitellinus (Scholtz, 1847) (Capsus) viticola (Johnston, 1935) (Sthenarus) vittiscutis Knight, 1923 = albatus (Van Duzee) yomogi Miyamoto, 1969 zuvandiensis Putshkov, 1978

RELATIONSHIPS WITHIN PLAGIOGNATHUS

The establishment of a scheme of phylogenetic relationships for the species of Plagiognathus is beyond the scope of the present paper for at least three reasons. First, my intention in revising the Nearctic species was to determine the limits for a monophyletic group containing the type Plagiognathus arbustorum (Fabricius) and to therefore more adequately assign a substantial fraction of all species­group names currently applied to the North American Phylini . Second, the subtlety of variation in many features—particularly the male genitalia—make the preparation of a morphological character matrix sufficient to resolve detailed relationships within the group an unlikely prospect. Third, the sample of Palearctic material available to me was quite small.

This is not to say, however, that some apparently monophyletic groups of species cannot be recognized. Not all Nearctic species can be satisfactorily accommodated in species groups. Furthermore, I have not tried to place the Palearctic species in groups, with the exception of Plagiognathus arbustorum , because I do not have information for all of those species comparable to that available for the Nearctic fauna. What seems clear is that most Nearctic species groups do not also contain species from the Palearctic. Note, however, that on the basis of genitalic structure, arbustorum , the type, probably finds its closest relatives in the New World.

New World Plagiognathus species can be grouped at four levels on the basis of available character information. I refer to these levels as cohorts, complexes, species groups, and species subgroups. Although some of the proposed groupings may not be monophyletic, others almost certainly are. The groupings are listed below, with the characteristics that seem to define them.

ARBUSTORUM COHORT · vesica usually with a well­developed flange · apical blades of the arbustorum type OBSCURUS COMPLEX

· antennal segment 1 dark

· pale marking at the extreme base of the membrane

fuscosus species group

All species in this group (except fuscosus ) were previously placed in Psallus Fieber , because

of the weakly to strongly flattened setae on the dorsum. The vesica in all species is, nonethe­

less, of the typical Plagiognathus type.

· dorsum with simple setae intermixed with weakly to strongly flattened setae

· hind femora often almost entirely castaneous to black

· tibial spines with black spots at bases

· antennal segment 2 usually dark at extreme base, pale on remainder ( alnicenatus and aster­

icola sexually dimorphic, morrisoni and parshleyi with antennal segment 2 dark in males

and females)

· dorsum entirely castaneous, some species with color forms with pale patches at base of

corium and sometimes cuneus

· small to medium­sized species (except parshleyi moderately large)

alnicenatus (Knight)

amorphae (Knight)

astericola (Knight)

fuscosus (Provancher)

morrisoni (Knight)

parshleyi (Knight)

physocarpi (Henry)

obscurus species group

Some members of this group are among the most frequently encountered species of Plagiog­

nathus. The pale and dark color pattern—in combination with the black antennal segments 1

and 2—allows for the placement of most species (and specimens) within this group. The most

obvious exceptions are the totally dark forms of brunneus , obscurus , and politus . Unlike

bivoltine politus , where the color forms appear to be strongly, if not exclusively, correlated

with a particular generation, no such correlation is clear in the case of brunneus and obscurus .

· corium pale on basal one­third

· cuneus pale, at least at base, sometimes entirely

· antennal segment 2 entirely black

· tibial spines with black spots at bases

· size large (except for subovatus )

· vestiture of dorsum usually composed of only simple, shining setae

alboradialis Knight

brevirostris Knight

brunneus (Provancher)

dimorphus , new species

flavoscutellatus Knight

mundus Van Duzee

notodysmicos , new species

obscurus Uhler

paramundus , new species

politus Uhler

subovatus Knight

moerens species group

Although the linear pattern of coloration is diagnostic, shoshonea , and also apparently lineatus

(see discussion under the latter species for potential confusion with brunneus ), may have

totally dark­colored forms, which in the absence of pale and dark specimens can make the

placement of specimens of these species questionable. Although lineatus , shoshonea , and ver­

ticalis have ‘‘typical’’ Plagiognathus male genitalia, those of moerens are distinctive, with

very long apical vesical spines. The dorsal vestiture of moerens and verticalis is black and

bristlelike, more conspicuously so in moerens .

· pale areas on hemelytra longitudinal, largely restricted to exocorium (and contiguous cuneus)

and clavus

· pronotum with disc or posterior lobe often pale lineatus Van Duzee shoshonea Knight moerens Reuter verticalis (Uhler) dispar species group

· legs, including hind femora, often almost entirely pale

· antennal segment 2 pale except at extreme base

· dorsum with recumbent, golden, shining setae

· dorsum mostly castaneous, more rarely with some pale patches dispar Knight louisianus , new species rileyi , new species delicatus species group

· antennal segment 2 partly to entirely pale

· dorsum at least partly pale, orange, or red, more rarely almost entirely dark albatus (Van Duzee) (sometimes dorsum black) cornicola Knight delicatus (Uhler) maculipennis Knight (tibial spines without dark spots at bases; antennal segment 1 pale) salicicola Knight tinctus Knight viticola (Johnston) (tibial spines without dark spots at bases; antennal segment 1 pale) laricicola species group

This is an assemblage of generally dull, brown to castaneous species without distinctive mark­

ings. With the exception of fuscipes , they all feed on conifers. The grouping is almost certainly

artificial, in that no obvious character (or characters) holds the listed species together. fenderi , new species fuscipes Knight laricicola Knight pemptos , new species piceicola , new species

MODESTUS COMPLEX

· hemelytra entirely dark without any pale markings (except eastern North American populations

of suffuscipennis with pale hemelytra)

modestus species group

This assemblage contains most, but not all, of the species that have previously been placed in Microphylellus Reuter. Recognition of such a group does not, however, offer a justification for recognizing Microphylellus as a valid genus, because members of the group have male genitalia that are of the typical Plagiognathus type, and the presence of pale legs and tibiae without dark spots at the bases of the spines is an attribute that occurs elsewhere in Plagiognathus . If Microphylellus were recognized as valid, then Plagiognathus would have to be split into several additional genera and at least half of the species currently placed in Microphylellus by Knight (see Schuh, 1995) would have to be placed in other genera; some would remain unassignable to any described genera (see ‘‘Species Incertae Sedis’’ section).

Members of this group usually have the following attributes:

· femora, tibiae, trochanters, and usually coxae pale

· tibial spines with pale or very weakly darkened area at bases (this feature also occurs in some delicatus ­group species, such as maculipennis Knight and viticola Johnston ; the tibial

spines in suffuscipennis have small dark spots at bases, an attribute that led Knight [1923] to place the species in Plagiognathus )

· antennal segment 2 entirely pale (except flavipes (Provancher))

Two subgroups can be recognized:

modestus species subgroup

· antennal segment 1 usually mostly pale

flavipes (Provancher)

longirostris (Knight)

modestus (Reuter) (antennal segment 1 occasionally dark)

tsugae species subgroup

· antennal segment 1 dark

· anterior vesical spine erect, very broad, and weakly sclerotized

· feed on members of the Pinaceae

suffuscipennis Knight

tsugae (Knight)

tumidifrons (Knight)

davisi species group

This pair of species is very similar in appearance except for the size, coloration of the legs, and usually the coloration of the antennae. The nature of the dorsal vestiture, although hard to describe, is apparently distinctive.

· dorsum with suberect, shining, simple setae

· head distinctly projecting anterior to eyes

davisi Knight (antennae sometimes almost entirely dark)

syrticolae Knight

annulatus species group

This group of species is certainly not monophyletic, but rather represents those dark­colored species that cannot be placed in other groups.

· dark species without pale markings on hemelytra

· antennal segments 1 and 2 black (except annulatus , flavicornis , and punctatipes )

annulatus Uhler

emarginatae , new species

flavicornis Knight

negundinis Knight

nigronitens Knight

pintoi, new species

punctatipes Knight

repetitus Knight

rideri , new species

schaffneri , new species

texanus , new species

urticae Knight

GUTTATIPES COMPLEX

· antennal segments 1 and 2 mostly pale

· dorsum mostly pale

guttatipes species group

flavidus Knight

guttatipes (Uhler)

shepherdiae Knight

SALVIAE COMPLEX

· clypeus and adjacent face castaneous, contrasting with remainder of head

· possibly all use Lamiaceae as hosts

salviae species group

fulvidus Knight

melliferae , new species

mexicanus , new species

salviae Knight Species unplaced within arbustorum cohort arbustorum (Fabricius) blatchleyi Reuter monardellae , new species stitti Knight

RIBESI COHORT · Ribes feeders · pale coloration · apical vesical spines long, overlapping · flange of vesica narrow ribesi species group cibbetsi , new species luteus Knight polhemorum , new species ribesi Kelton

LATTINI COHORT · suberect setae on dorsum · antennal segment 2 dark basally and distally · large, body elongate and slender · apical vesical spines relatively short · flange of vesica narrow lattini species group hallucinatus , new species lattini , new species rosicoloides , new species

CONCOLORIS COHORT · apical vesical spines short · dorsum uniformly pale · apical vesical spines relatively short · flange of vesica narrow concoloris species group concoloris , new species flavus Knight grandis Reuter longipennis (Uhler) lonicerae , new species phaceliae , new species tenellus Knight

Species unplaced to cohort or species group The following species do not fit easily in any of the above groupings, either because of contradictions in the pattern of coloration or the details of genitalic morphology. albifacies Knight aquilinus , new species atricornis Knight fulvaceus Knight rosicola Knight

BIOLOGY

Many Plagiognathus species are host­specific on woody plants and have one generation per year, a life history typical of the Phylini in general. However, some species feed on annual plants and some have more than one generation per year; these species—notably Pla­