Psallus alnicenatus Knight, 1923: 466

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 : 38-39

Psallus alnicenatus Knight, 1923: 466 (n. sp.). Psallus parshleyi fuscatus Knight, 1923: 466 (n.

var.). NEW SYNONYMY.

DIAGNOSIS: Recognized by the medium to moderately large size, elongate body form, pronotum with flattened scalelike setae dorsolaterally and on pleuron, brownish, mottled coloration of the dorsum, the frequent occurrence of pale markings on the pronotal disc and laterally on the scutellum (fig. 5), and antennal segment 2 entirely dark or at least largely infuscate; coxae and trochanters usually entirely pale. Costal vein pale only when other areas of dorsum also pale. Flange on vesica very broad. Sexual dimorphism relatively strong in most populations. Similar to astericola, morrisoni , and parshleyi in presence of scalelike setae on pronotum and dark coloration of antennal segment 2. Similar in size to parshleyi , but distinguished by the more brownish coloration of the dorsum and the scutellum frequently being pale laterally. Larger than astericola and morrisoni , and those species never with scutellum pale laterally.

REDESCRIPTION: Male: Elongate, nearly parallel­sided to elongate ovoid, of moderately large size; total length 3.36–4.28, length apex clypeus–cuneal fracture 2.27– 2.82, width across pronotum 1.04 –1.21. COLORATION (fig. 5): Dorsum generally brown, of variable intensity, often with pale on disc of pronotum, scutellum pale laterally, basal one­third to one­half of endocorium and most of clavus pale, corium narrowly pale adjacent to extreme base of membrane, and basal one­half or more of cuneus pale; membrane fumose, veins pale; face highly polished and appearing more deeply castaneous at and below base of clypeus; posterior margin of vertex always pale; antennal segment 1 castaneous except for pale apical an­ nulus, segment 2 entirely dark (fig. 15), segments 3 and 4 infuscate; labium, except segment 1, pale to weakly infuscate; venter mostly brown, metathoracic scent­gland evaporatory area mostly pale; legs, including most of coxae, pale or light brown, hind femora more heavily infuscate, all femora with some dark spots; dorsal tibial spines with dark spots at bases and tibiae dark at articulation with femora. SURFACE AND VES­ TITURE: Dorsum weakly granular, smooth, dull. Vestiture of dorsum composed of recumbent, golden, shining, simple setae, sometimes appearing weakly woolly; pronotum with moderately flattened scalelike setae dorsolaterally and on pleuron. STRUC­ TURE: Body elongate, nearly parallel­sided to very elongate ovoid; frons only weakly convex as viewed from above, clypeus visible; anteocular distance equal to diameter of antennal segment 1, head projecting below eyes by diameter of antennal segment 1; labium reaching to about apex of hind coxae. GENITALIA (fig. 20): Body of vesica relatively stout, more or less J­shaped, base of vesica falling well below level of secondary gonopore, posterior apical spine elongate, nearly straight, obliquely angled relative to body of vesica, anterior spine conspicuously longer than posterior, distinctly bent subapically, at about 45° angle to body of vesica, angle between spines acute; flange on vesica moderately broad, reaching to about base of gonopore, underlying strap conspicuously visible and extending to about midpoint of gonopore.

Female: Very similar to male in coloration, although body shorter, broader, and much more strongly ovate (fig. 5); antennal segment 2 usually obviously pale on distal two­thirds (fig. 15), in contrast to male; abdomen with large pale areas in specimens with pale coloration on dorsum. Total length 3.11–3.66, length apex clypeus–cuneal fracture 2.13–2.59, width across pronotum 1.00– 1.16.

HOST: Breeds on Alnus spp. (Betulaceae) . Records from the Pinaceae almost certainly do not represent breeding hosts.

DISTRIBUTION: Well documented from Pennsylvania west to Illinois and north to Manitoba and Nova Scotia. Also recorded from Florida, although not from intervening localities.

DISCUSSION: Knight’s (1923) placement of this species in Psallus was based on the presence of flattened setae, particularly on the lateral margins of the pronotum and the propleuron. The structure of the male genitalia, however, clearly places alnicenatus in Plagiognathus .

Knight (1923) described Plagiognathus fuscatus as a variety of Psallus parshleyi on the basis of three specimens from Minnesota, placing it in Psallus because of what he deemed to be the distinctive nature of the vestiture. He later (Knight, 1941) treated fuscatus as a valid species, recording the host as Alnus rugosa (alder). Comparison of Knight’s types and paratypes of alnicenatus in the National Museum of Natural History, Washington, D.C., with topotypical material of fuscatus identified by Knight suggests that the two nominal species are the same, based on the coloration of antennal segment 2 and the nature of the scalelike setae on the pronotum and propleuron. The hosts, as recorded by Knight (1923, 1941), are the same for the two nominal species. The genitalia of alnicenatus and those of specimens from Eichorn, Illinois, identified by Knight as fuscatus are nearly identical.

SPECIMENS EXAMINED: CANADA.— Manitoba: Riding Mt. Natl. Park, July 21, 1972, L. A. Kelton, 13 (CNC). New Brunswick: Kouchibouguac Natl. Park, July 27, 1977, D. J. Brown, Alnus sp. (Betulaceae) , 283, 25♀ (CNC). Nova Scotia: Kentville, July 15, 1966, L. A. Kelton, 1♀ (CNC). Truro, August 4, 1917, paratype: 13 (CAS). Woodville, July 20, 1966, L. A. Kelton, Alnus sp. (Betulaceae) , 13, 2♀ (cbc). Woodville, July 20, 1966, L. A. Kelton, Alnus sp. (Betulaceae) , 73, 11♀ (CNC). Ontario: Corkery, July 4, 1962, D. Brown, Alnus sp. (Betulaceae) , 13 (CNC). Corkery, July 4, 1962, D. Brown, Alnus sp. (Betulaceae) , 63, 2♀ (CNC). Ipperwash, July 11, 1962, Kelton and Thorpe, 13, 1♀ (CNC). Lac Brule, August 6, 1951, O. Peck, Alnus sp. (Betulaceae) , 2♀ (CNC). Otter Lake, July 26, 1962, Kelton and Thorpe, Alnus sp. (Betulaceae) , 1♀ (CNC). Otter Lake, July 26, 1962, Kelton and Thorpe, Alnus sp. (Betulaceae) , 203, 14♀ (CNC). Parry Sound, July 26, 1962, Kelton and Thorpe, 1♀ (CNC). Stittsville, August 9, 1962, D. Brown, Alnus sp. (Betulaceae) , 7♀ (CNC). Stittsville, July 26, 1961, G. Brumpton, 2♀ (CNC). Sturgeon Falls, July 27, 1962, Kelton and Thorpe, Alnus sp. (Betulaceae) , 3♀ (CNC). Thessalon, August 15, 1965, W. Gagne, 23 (UCB). Prince Edward Island: Charlottetown, August 7, 1976, L. A. Kelton, Alnus sp. (Betulaceae) , 13, 2♀ (CNC). Quebec: Chicoutimi, July 24, 1915, G. Beaulieu, 1♀ (USNM). Chicoutimi, July 24, 1915, G. Beaulieu, 53 (CNC). Fabre, July 12, 1963, W. Gagne, 13 (CNC). Lac Megantic, August 3, 1961, G. Brumpton, 3♀ (CNC). Ladysmith, July 23, 1958, L. A. Kelton, Picea sp. (Pinaceae) , 23 (CNC). Laniel, July 20, 1963, W. Gagne, Alnus sp. (Betulaceae) , 133, 10♀ (CNC). Levis, August 6, 1961, G. Brumpton, 1♀ (CNC). Magog, August 2, 1961, G. Brumpton, 43, 4♀ (CNC). Old Chelsea, August 10, 1962, G. Thorpe, Alnus sp. (Betulaceae) , 4♀ (CNC). St. Agathe, August 9, 1961, G. Brumpton, 2♀ (CNC). USA.— Connecticut: Storrs, June 30, 1964, J. A. Slater, 83 (AMNH). Florida: Liberty Co.: W of Bristol along Apalachicola River, May 8, 1981, T. J. Henry, Alnus serrulata (Betulaceae) , 83, 1♀ (USNM). Illinois: Hardin Co.: Eichorn, Hick’s Branch, June 24, 1932, Mohr, Dozier, Park, Alnus rugosa (Betulaceae) , 13, 2♀ (AMNH). Eichorn, Hick’s Branch, June 24, 1932, Ross, Dozier, Park, Alnus rugosa (Betulaceae) , 1♀ (USNM). Maine: Waldo Co. : Lincolnville, August 23, 1900, E. B. Bryant, 13 (AMNH). Massachusetts: Hampden Co.: Chester, August 8, 1912, H. M. Parshley, 1♀ (CAS). Norfolk Co.: Sharon, July 20, 1909, E. P. Van Duzee, 13 (CAS). Wellesley, June 7, 1910, E. P. Van Duzee, 13 (CAS). Minnesota: Lake Co.: Beaver Bay, August 20, 1920, H. H. Knight, 4♀ (USNM). Cramer, August 10, 1922, H. H. Knight, 13 (USNM). Winona Co. : Kings Bluff, June 30, 1922, H. H. Knight, 1♀ (USNM). New Hampshire: Coos Co.: Gorham, July 18, 1929, G. S. Walley, 1♀ (CNC). New York: St. Lawrence Co.: Cranberry Lake, July 26, 1917, H. H. Knight, paratype: 13 (USNM). Suffolk Co.: East Quogue, Quogue Wildlife Refuge, July 19, 1988, M. D. Schwartz, Picea sp. (Pinaceae) , 13 (AMNH). Tompkins Co.: Ithaca, July 1, 1920 – July 8, 1920, H. H. Knight, 23, 1♀ (USNM). Ithaca, July 1, 1920, H. H. Knight, paratypes: 103, 10♀ (USNM). Ithaca, July 8, 1920, H. H. Knight, paratypes: 23, 2♀ (USNM). Ithaca, Ringwood Road, August 1, 1982, A. G. Wheeler, Jr., Alnus sp. (Betulaceae) , 23, 4♀ (PDA). McLean Bogs, July 3, 1920, 63, 6♀ (USNM). McLean Bogs, July 3, 1920, H. H. Knight, paratypes: 13, 1♀ (CAS). McLean Bogs, July 3, 1920, H. H. Knight, paratypes: 103, 10♀ (USNM); holotype male (USNM). McLean, July 27, 1916, H. H. Knight, 13 (USNM). McLean, July 27, 1916, H. H. Knight, paratypes: 103, 10♀ (USNM). Pennsylvania: Centre Co.: State College, July 28, 1963, D. J. Burdick, 13, 1♀ (UCB).