Canadian Journal of Arthropod Identification
 
 

Taxonomic revision of the Nearctic erosa species group of Phymata Latreille, 1802 (Heteroptera: Reduviidae: Phymatinae)

CJAI 41 -- October 1, 2020
doi:10.3752/cjai.2020.41

Paul Masonick & Christiane Weirauch

| Abstract | Introduction | Checklist | Materials & Methods | Species Key | Taxonomy | Acknowledgments | References | PDF | Cite |
| Appendix |
 
  Phymata pennsylvanica Handlirsch, 1897
    Figs 15A–F, 20M, 21E, 22A–C. Map 13.

Phymata erosa pennsylvanica Handlirsch, 1897
Handlirsch, 1897: p163 (original description)
Phymata americana newyorkensis Melin, 1931
Melin, 1931: p7 (original description); Evans, 1931: p714 (synonym)
Phymata pennsylvanica Handlirsch, 1897
Kormilev, 1953: p63 (taxonomy); Kormilev, 1962: p394 (revision); Henry and Froeschner, 1988: p603 (catalog); Froeschner and Kormilev, 1989: p56 (catalog)

Diagnosis: Recognized from other species of the Nearctic erosa group by the following combination of characters: (1) lateral notch of medium depth, (2) integument lacking elongated setaceous granulation, (3) lateral margin of anterior pronotal lobe never keeled, (4) lateral and posterior pronotal angles prominent and often acute, (5) posterior pronotal disk punctate, (6) connexiva of abdominal segments 3–4 pale, usually without dark marginal spots, (7) lateral margins of connexiva of abdominal segments 4–5 more or less straight, and (8) wing membrane brownish.

Redescription: Male: Medium to large, total length: ~7.73–8.67 mm, width across lateral angles of pronotum: ~2.75–3.09 mm. STRUCTURE: HEAD (Fig. 15B): distiflagellomere longer than pedicel + basiflagellomere (dflg : pd + bflg = ~1.15). THORAX (Figs 15A,B,E, 20M): thoracic surface matte; anterior pronotal disk without elongated setaceous granulation; posterior pronotal disk punctate; area between lateral pronotal notch and longitudinal carina of the posterior pronotal either with diffuse granulation or devoid of granulation; longitudinal carina without prominent tubercle; lateral margin of anterior pronotal lobe not keeled; lateral notch of medium depth; lateral margin of pronotum from lateral notch to lateral angle smooth or with light crenulation; lateral angle prominent and acute; posterior angle prominent and acute; lateral surface of forefemur smooth or sparsely granulated; lateral surface of thorax smooth or sparsely granulated; forewing membrane brown, cloudy, never hyaline. ABDOMEN (Fig. 15C): posterior corners of connexiva of abdominal segments 2–4 inconspicuous/subtle; lateral margins of connexiva of abdominal segments 4–5 concave or straight; lateral margins of connexiva of abdominal segments 3–6 with or without fine granulation; connexivum of abdominal segment 5 twice as wide as connexivum of abdominal segment 4; connexivum of abdominal segment 6 trapezoidal, anterior margin roughly twice as wide as posterior margin. COLORATION (Figs 15A–E): head (dorsal and lateral surfaces), distiflagellomere, pronotum, scutellum, and entire connexivum of abdominal segment 5 and anterior portion of connexivum of abdominal segment 6 are usually dark brown to black and mostly uniform in color, the pronotum sometimes bears a narrow light-colored marking along the margin of the lateral notch; forefemur never darkly pigmented; corium with a dark transverse band (sometimes reddish-brown or purplish) that faintly contrasts with the rest of the corium; lateral thoracic surface divided into distinct dark-colored (dorsal) and light-colored (ventral) regions (contrast with P. americana); connexiva of abdominal segments 3–4 usually without dark basal spots (this character is plastic as many northern populations do exhibit basal spots like P. americana); spiracle of abdominal segment 6 usually surrounded by dark pigmentation. NOTE: While the legs, connexiva of abdominal segments 2–4 and 6–7, and overall ventral surfaces of live specimens tend to be lime-green or bright yellow, these colors quickly fade to drab yellow or beige on specimens that are pinned or preserved in alcohol. The eyes of live males are also usually orange or reddish in color. Female: Large, total length: ~8.97–9.55 mm, width across lateral angles of pronotum: 3.16–3.50 mm. STRUCTURE: HEAD (Fig. 15A): distiflagellomere relatively long, only slightly shorter than pedicel + basiflagellomere (dflg : pd + bflg = ~0.88). COLORATION (Figs A,C,D,F): pronotum mostly reddish-brown to chestnut in color and never as dark as in males; lateral surface of the body is similar in pattern to that of males, however, is generally lighter brown and never black; the transverse corial band ranges from beige to chestnut brown; lateroventral surface of abdominal sternites 5–7 sometimes with faint or diffuse brown coloration.

Biology: Males are often seen mate guarding females. This species is found on a variety of plants but perhaps is most frequently encountered on Asteraceae. Specimens have been collected at elevations ranging between 3–1,158 m above sea level.

Distribution: P. pennsylvanica is found primarily east of the Mississippi River and is very common during summer months. It ranges from southern Canada across New England and Appalachia south into Florida and west over the Ozark Plateau.

Discussion: This species is slightly smaller than P. americana, the species with which it is most likely to be confused. The ranges of these two species are largely parapatric and overlap in New England and the Great Lakes region (see Swanson 2013). See discussion section of P. americana for additional information pertaining to these two species.

Identification remarks: A combination of these additional characteristics may help separate P. pennsylvanica from P. americana: (1) a distiflagellomere that is in males distinctly longer than the scape and basiflagellomere combined or in females roughly subequal in length, (2) pronotum mostly uniform in color (black in males and brown in females), (3) corium with a subtle, dark transverse band (this band is very conspicuous in P. americana), (4) absence of dark markings along anterior margins of connexiva of abdominal segments 3–4, (5) relatively smooth anterior margins of connexiva of abdominal segments 2–4, (6) abruptly dilated connexivum of abdominal segment 5 in males (abdomen of both sexes appearing more diamond shaped when viewed dorsally), (7) lateral thoracic surface divided into distinct dark-colored (dorsal) and light-colored (ventral) regions, (8) dark pigmentation that usually encircles the spiracles of abdominal segments 5 and 6, and (9) the general lack of diffuse granulation on the pronotum between the lateral notch and longitudinal carina. Lastly, while P. pennsylvanica usually bears well developed preocellar and ocellar processes, these structures are often shorter and less branched than those of P. americana.

Type information: Handlirsch only selected syntypes for ambush bug species he described. The syntype series of P. pennsylvanica is housed at the Natural History Museum Vienna and was cataloged by Rabitsch (2000). We here designate one of these specimens to serve as a lectotype. Images of a syntype of Phymata americana newyorkensis Melin, 1931 were also examined.
LECTOTYPE: Male: USA: Pennsylvania: H. G. Klages (UCR_ENT 00075081) (NHMW). Fig. 22A–C.
SYNTYPE: (Phymata americana newyorkensis Melin, 1931): Male: (NRM). Fig. 21E. Image: http://www2.nrm.se/en/het_nrm/a/phymata_americananewyorkensis.html

Additional material examined: See Appendix; 123 specimens, including 69 adult males and 54 adult females.