Dicyphus Fieber, 1858

Konstantinov, Fedor V. & Neimorovets, Vladimir V., 2021, Bryocorinae Baerensprung, 1860 (Hemiptera: Heteroptera: Miridae) of European Russia and the Caucasus: synopsis and key to species, Zootaxa 4920 (3), pp. 301-338 : 307-308

Dicyphus Fieber, 1858

The genus Dicyphus includes 60 zoophytophagous species in the World fauna and particularly speciose in the Mediterranean region. Several species, e.g., Dicyphus hesperus are widely used in the control of agricultural pests in Europe. Species of the genus may be usually found in shaded woods where they inhabit herbaceous plants with a pilose and glutinous epidermis.

Key to species

1. Calli small, distinctly separated, in doubtful cases with pale midline between them. Head short, distinctly transverse, posterior margin of eye located at a small distance from pronotum ( Fig. 2 ). Always macropterous. Body robust, 3–4 X as long as basal width of pronotum, with short antenna and legs. (subgenus Brachyceroea )........................................ 8

- Calli, large, contiguous or fused along midline. Head almost as long as wide, with well-developed postocular region, so that eye is distinctly removed from pronotum ( Figs. 3–5 ). Macropterous or brachypterous. Body in macropterous forms gracile, 4–6 X as long as basal width of pronotum, with long antenna and legs. (subgenus Dicyphus )............................... 2

2. In macropterous specimens, male antennal segment II less than 1.4 X as long as basal width of pronotum, female subequal. In brachypterous specimens, antennal male segment II 1.1–1.4 X as long as basal width of pronotum, female 1.0–1.2 X....... 3

- In macropterous specimens, male antennal segment II more than 1.5 X as long as basal width of pronotum, female 1.25 X. In brachypterous specimens, male antennal segment II more than twice as long as basal width of pronotum, female more than 1.5 X.................................................................................................. 5

3. Abdominal segment VIII in male with tumid setose process on left lateral side ( Fig. 7 ). Left paramere with very long setae on sensory lobe ( Fig. 11 ). Always macropterous.......................................................... cerastii

- Abdominal segment VIII not expanded. Left paramere with comparatively short setae on sensory lobe. Both sexes often brachypterous, sometimes macropterous................................................................... 4

4. Left paramere more robust, with strongly convex inner margin of sensory lobe ( Fig. 11 ). Both sexes usually brachypterous, rarely macropterous ( Fig. 4 ). In macropterous specimens pronotum less than twice as wide as pronotal collar; anterior part of pronotum longer than or as long as posterior part (measure from anterior margin of pronotal collar to suture behind calli and from suture to posterior angles of pronotum).......................................................... stachydis

- Left paramere smaller, with slightly convex inner margin of sensory lobe. Both sexes usually macropterous. Posterior part of pronotum distinctly expanded posteriorly, more than twice as wide as pronotal collar; anterior part of pronotum shorter than posterior part............................................................................... hyalinipennis

5. Calli at most 1.5 X as long as pronotal collar at middle; pronotum behind calli 1.6–1.8 X as long as calli in both sexes...... 6

- Calli large, at least 2.0 X as long as pronotal collar at middle; pronotum behind calli 1.2–1.3 X as long as calli in macropterous forms, subequal or shorter than calli in brachypterous forms.................................................... 7

6. Spatulate apex of the right paramere with wide dorsal crest ( Fig. 11 ). Darker, pronotum usually more or less darkened, rarely pale brown ( Fig. 3 ). Antennal segment I dark brown to reddish brown........................................ errans

- Spatulate apex of the left paramere with narrow dorsal crest ( Fig. 11 ). Pronotum pale brown, sometimes with partly darkened calli. Antennal segment I reddish, segment II pale brown with more or less darkened base and apex............... epilobii

7. Left paramere distinctly larger and more robust, with small dorsal crest terminating in apical one-third of apical process. Sensory lobe distinctly developed, apical process distinctly narrowed at base ( Fig. 11 ). All femora, especially ventral margin of hind femur with erect dark bristlelike setae slightly longer than width of hind tibia. Larger ( Fig. 5 ), with long appendages, body length macropterous 5.4–6.0, brachypterous 4.3–5.4..................................................... pallidus

- Left paramere smaller, with dorsal crest occupying about half of total length of apical process, similar in shape to that of D. errans , but with apical process located almost at right angle to body of paramere. All femora clothed with pale yellowish, rarely brown setae. Smaller, body length macropterous 4.4–5.5, brachypterous 3.6–4.2........................... сonstrictus

8. Antennal segments dark, base and apex of segment I, and sometimes extreme apex of segment II whitish. Calli uniformly dark brown............................................................................................... 9

- All antennal segments dark, with dirty whitish bases, segment II sometimes with pale ring at middle. Calli pale or with more or less mottled dark pattern, never entirely dark brown......................................................... 10

9. Anterior part of pronotum dark brown to black, without pale midline between calli ( Fig. 2 ). Base of pronotum finely rugose, with scarce, shallow punctures. Body length 3.4–4.9. Apical process of left paramere slightly and gradually curved at midpoint ( Fig. 10 ), with dorsal crest terminating at half-length of apical process................................... geniculatus

- Anterior part of pronotum with yellow to dirty orange midline, sometimes narrow but always entirely separating calli. Base of pronotum distinctly rugose, with dense, coarse punctures. Body length 3.3–3.9. Apical process of left paramere strongly curved at apex, with large dorsal crest occupying about two-thirds of total length of apical process.................... globulifer

10. Antennal segment II whitish, sometimes with an indistinct ring at middle. Calli distinctly raised, well delimited, whitish, entirely covered with weak transverse and confluent dark stripes ( Fig. 2 ). Dorsum with large bristlelike setae distinctly longer than width of hind tibia. Larger, 3.3–4.0. Left paramere ( Fig. 10 ) long and thin, with moderately swollen sensory lobe, apical process arrow-shaped, with contrastingly short dorsal crest.................................................... 11

- Antennal segment II uniformly black. Calli weakly raised, uniformly pale or somewhat darkened posteriorly. Dorsum with comparatively short black setae almost equal in length to width of hind tibia. Smaller, body length 2.4–3.0. Left paramere small, with distinctly swollen sensory lobe, apical process straight, gradually curving apically, with large dorsal crest occupying more than half length of apical process................................................................ montandoni

11. Smaller, total body length male 3.0–3.5, female 3.1–3.7. Head with dark brown spots at bases of setae. Tibiae with dark brown spots at bases of tibial spines ( Fig. 2 ). Spatulate apex of left paramere attenuating apically, with weakly developed ventral crest ( Fig. 10 )................................................................................... albonasutus

- Larger, total body length male 3.8–4.5, female 3.9–4.4. Head and tibiae without brown spots at bases of setae and tibial spines. Spatulate apex of left paramere finely upturned and rounded, with well-developed ventral crest................ digitalidis

Figures

FIGURE 2. Dorsal habitus images of Dicyphus (Brachyceroea) spp. Dicyphus (B.) albonasutus Wagner, 1951, Dicyphus (B.) geniculatus (Fieber, 1858), Dicyphus (B.) digitalidis Josifov, 1958, Dicyphus (B.) globulifer (Fallén, 1829), and Dicyphus (B.) montandoni Reuter, 1888.

FIGURE 3. Dorsal habitus images of Dicyphus (Dicyphus) spp. Dicyphus (D.) errans Wolff, 1804 and Dicyphus (D.) epilobii Reuter, 1883.

FIGURE4. Dorsalhabitus imagesof Dicyphus(Dicyphus) spp.Dicyphus (D.) cerastiiWagner,1951,Dicyphus (D.) hyalinipennis (Burmeister, 1835), and Dicyphus (D.) stachydis J. Sahlberg, 1878.

FIGURE 5. Dorsal habitus images of Dicyphus (Dicyphus) spp. Dicyphus (D.) constrictus (Boheman, 1852) and Dicyphus (D.) pallidus (Herrich-Schaeffer, 1836).

FIGURE 7. Images of male abdominal apex of Dicyphus (D.) spp. in left lateral (above) and dorsal (below) views, respectively. Dicyphus (D.) cerastii Wagner, 1951, Dicyphus (D.) errans Wolff, 1804, Dicyphus (D.) constrictus (Boheman, 1852), Dicyphus (D.) hyalinipennis (Burmeister, 1835), and Dicyphus (D.) stachydis J. Sahlberg, 1878, Dicyphus (D.) pallidus (Herrich-Schaeffer, 1836).

FIGURE 10. Images of parameres of Dicyphus (Brachyceroea) spp. Dicyphus (B.) albonasutus Wagner, 1951, Dicyphus (B.) geniculatus (Fieber, 1858), Dicyphus (B.) globulifer (Fallén, 1829), Dicyphus (B.) digitalidis Josifov, 1958, and Dicyphus (B.) montandoni Reuter, 1888.

FIGURE 11. Images of parameres of Dicyphus (Dicyphus) spp. Dicyphus (D.) constrictus (Boheman, 1852), Dicyphus (D.) cerastii Wagner, 1951, Dicyphus (D.) errans Wolff, 1804, Dicyphus (D.) epilobii Reuter, 1883, Dicyphus (D.) hyalinipennis (Burmeister, 1835), Dicyphus (D.) pallidus (Herrich-Schaeffer, 1836), and Dicyphus (D.) stachydis J. Sahlberg, 1878.