Eustrophopsis bicolor (Fabricius, 1792)

Pollock, Darren A., 2012, Review of the Eustrophinae (Coleoptera, Tetratomidae) of America north of Mexico, ZooKeys 188, pp. 1-153 : 15-18

Eustrophopsis bicolor (Fabricius, 1792) Figures 6193143576369

Mycetophagus bicolor Fabricius 1792: 497.- Fabricius 1801: 566; Olivier 1811: 70.

Eustrophus bicolor (Fabricius).- Melsheimer 1853: 143; Crotch 1873: 112; LeConte 1873: 335; Provancher 1877: 467; Schwarz 1878: 463; Henshaw 1885: 124; Horn 1888: 35; Weiss 1919: 133; Weiss and West 1920: 10; Weiss 1922: 47; Csiki 1924: 8.

Eustrophinus bicolor (Fabricius).- Leng 1920: 238; Poole and Gentili 1996: 299; LeSage 1991: 246; Viedma 1971.

Eustrophopsis bicolor (Fabricius).- Pollock 2008: 277, 290; Lawrence and Leschen 2010: 515, fig. 11.5.2.D.

Diagnosis.

This common species may be separated from the other Nearctic Eustrophinae based on the following combination of characters: antennomeres distinctly contrasting: 1-4 rufous, 5-10 dark piceous to black, 11 yellow-orange; pronotal punctation very fine, punctures not larger than diameter of setae; males with oval, setiferous pit on ventral edge of profemur; meso- and metatibiae with numerous, oblique ridges.

Description

(from Pollock 2008: 277). TL 4.2-6.5 mm; GEW 2.0-3.2 mm. Body elongate oval, moderately tapered posteriorly (Fig. 6), distinctly convex dorsally (Fig. 19); dorsal color dark piceous to black; antennae tricolored: antennomeres 1-4 red, 5-10 piceous, antennomere 11 yellow-red, distinctly contrasting against preceding darker antennomeres; maxillary palpi similar in color to basal antennomeres; venter a combination of dark (same as dorsum) and lighter colored sclerites (abdominal ventrites in most specimens contrasting darker color of thorax); dorsal pubescence relatively long, conspicuous; eyes narrowly separated (Fig. 31), or almost contiguous (space <length of antennomere 1), medial margin moderately emarginate; antennomeres 2-4 short, submoniliform, antennomeres 5-10 widened, becoming more triangular toward antennomeres 9-10; antennal sensilla completely annular; last maxillary palpomere not modified; prosternal process (Fig. 43) triangular, narrowed distally, extended to slightly short of posterior margin of procoxae; prothoracic episternal suture present; elytral punctation coarse, punctures arranged in longitudinal striae; meso- and metatibiae with oblique ridges present; male with small, ovate setiferous pit on ventral edge of profemur; aedeagus (Figures 57, 63) with basal and apical piece of tegmen subequal in length; struts on median lobe elongate, narrow, inner margins V-shaped; sternite 9 basally Y-shaped, with short stem.

Distribution

(Fig. 69). Eustrophopsis bicolor is the most commonly collected and/or geographically widespread species in the subfamily. It exhibits an eastern distribu tion in Canada, with no records west of Winnipeg, Manitoba. In the United States, most records are eastern; however, scattered localities are known from several western states. This species is the only otherwise Nearctic eustrophine recorded from the West Indies. The 2,799 examined specimens are from the following jurisdictions: BAHAMAS. CANADA: MANITOBA, ONTARIO, QUEBEC. UNITED STATES: ALABAMA: Colbert, Greene, Jefferson, Lee, Madison, Mobile, Tuscaloosa. ARIZONA. Santa Cruz. ARKANSAS: Faulkner, Fulton, Garland, Hempstead, Johnson, Polk, Pulaski, Washington. CALIFORNIA: Trinity. COLORADO: Larimer. CONNECTICUT: Fairfield, Litchfield, New Haven, Tolland. DELAWARE: New Castle, Sussex. DISTRICT OF COLUMBIA. FLORIDA: Alachua, Baker, Brevard, Calhoun, Dade, Duval, Hernando, Highlands, Hillsborough, Jackson, Liberty, Monroe, Okeechobee, Orange, Osceola, Pinellas, Polk, Seminole, St. Lucie, Volusia, Wakulla. GEORGIA: Baker, Bartow, Calhoun, Camden, Clarke, Dekalb, Dougherty, Floyd, Fulton, Greene, Gwinnett, Lowndes, McIntosh, Meriwether, Muscogee, Paulding, Rabun, Thomas. IDAHO: Jerome, Twin Falls. ILLINOIS: Adams, Alexander, Calhoun, Champaign, Clark, Clay, Clinton, Coles, Cook, DuPage, Edgar, Effingham, Jackson, Jasper, Jefferson, Jersey, Johnson, Kendall, lake, LaSalle, Lawrence, Macon, Marion, Mason, McHenry, McLean, Peoria, Pike, Platt, Pope, Putnam, Richland, Sangamon, Stephenson, Vermilion, Wabash, Washington, White, Whiteside, Will, Winnebago. INDIANA: Bartholomew, Crawford, Howard, Lake, Laporte, Monroe, Parke, Perry, Porter, Posey, Tippecanoe, Vigo, Wayne. IOWA: Benton, Henry, Keokuk, Johnson, Linn, Osceola, Story. KANSAS: Atchison, Douglas, Labette, Lyon, Miami, Riley, Sedgwick, Shawnee, Trego, Wilson, Wyandotte. KENTUCKY: Butler, Christian, Green, Henderson, Taylor. LOUISIANA: Bossier, Caddo, Claiborne, Concordia, East Baton Rouge, East Feliciana, Jefferson, Livingstone, Madison, Natchitoches, Orleans, Webster, West Feliciana. MARYLAND: Allegany, Anne Arundel, Baltimore, Calvert, Caroline, Cecil, Charles, Dorchester, Frederick, Montgomery, Prince George’s, Queen Anne’s, St. Mary’s, Talbot, Wicomico, Worcester. MASSACHUSETTS: Bristol, Dukes, Essex, Hampden, Hampshire, Middlesex, Norfolk, Suffolk, Worcester. MICHIGAN: Allegan, Berrien, Branch, Charlevoix, Clare, Clinton, Eaton, Ingham, Isabella, Kalamazoo, Kent, Lake, Lenawee, Livingston, Marquette, Midland, Monroe, Oakland, Ottawa, Saginaw, Schoolcraft, Shiawassee, Washtenaw, Wayne. MINNESOTA: Crow Wing, Hennepin, Washington. MISSISSIPPI: Bolivar, George, Issaquena, Jackson, Lafayette, Montgomery, Perry, Prentiss, Tallahatchie, Tishomingo. MISSOURI: Boone, Butler, Clay, Franklin, Greene, Jackson, Morgan, Randolph, Reynolds, St. Charles, St. Louis, Vernon. MONTANA: Richland, Rosebud, Valley. NEBRASKA: Cass, Colfax, Cuming, Douglas, Fillmore, Hall, Keith, Lancaster, Merrick, Nemaha, Sarpy, Saunders, Sheridan, Sioux, Thomas. NEW HAMPSHIRE: Rockingham, Strafford. NEW JERSEY: Bergen, Burlington, Cape May, Essex, Gloucester, Mercer, Middlesex, Monmouth, Morris, Ocean, Passaic, Salem, Union. NEW MEXICO: Roosevelt. NEW YORK: Bronx, Columbia, Erie, Nassau, Niagara, Onondaga, Queens, Richmond, Rockland, St. Lawrence, Schuyler, Suffolk, Tompkins, Westchester, Wyoming. NORTH CAROLINA: Bladen, Buncombe, Carteret, Columbus, Durham, Haywood, Henderson, Johnston, Macon, Moore, Robeson, Wake. NORTH DAKOTA: Burleigh, Cass, Ransom, Richland. OHIO: Ashland, Clark, Clermont, Clinton, Cuyahoga, Erie, Franklin, Greene, Hamilton, Hancock, Licking, Montgomery, Ottawa, Scioto, Union, Warren. OKLAHOMA: Adair, Atoka, Beckham, Bryan, Caddo, Cherokee, Cleveland, Garfield, Grady, Latimer, Lincoln, Love, Marshall, Mayes, Muskogee, Okfuskee, Oklahoma, Osage, Payne, Pontotoc, Roger Mills, Tillman, Tulsa, Wagoner. PENNSYLVANIA: Allegheny, Berks, Bucks, Butler, Centre, Chester, Cumberland, Dauphin, Delaware, Erie, Greene, Lancaster, Philadelphia, Westmoreland. RHODE ISLAND: Newport, Providence. SOUTH CAROLINA: Abbevilee, Beaufort, Chester, Clarendon, Dorchester, Florence, Greenville, Kershaw, Oconee, Pickens, Sumter. SOUTH DAKOTA: Brookings, Yankton. TENNESSEE: Cumberland, Davidson, Hardeman, Knox, Lake, Lauderdale, Madison, McMinn, Shelby. TEXAS: Anderson, Angelina, Aransas, Bastrop, Bexar, Blanco, Brazoria, Brazos, Brewster, Brown, Caldwell, Cameron, Cass, Cherokee, Comal, Dallas, Denton, Galveston, Gonzales, Hardin, Harris, Hidalgo, Houston, Jeff Davis, Kenedy, Kerr, Live Oak, Mason, McLennan, Montague, Montgomery, Palo Pinto, Polk, Robertson, Sabine, San Augustine, San Patricio, Smith, Tarrant, Throckmorton, Travis, Tyler, Walker, Williamson, Wood. UTAH: Utah, Washington. VIRGINIA: Bath, Chesapeake, Chesterfield, Clarke, Covington, Essex, Fairfax, Hampton, Loudoun, Newport News, Suffolk, Westmoreland, York. VERMONT: Bennington. WASHINGTON: Asotin. WISCONSIN: Columbia, Dane, Dodge, Green, Jackson,

Milwaukee, Racine, Sauk, Wood. WEST VIRGINIA. Barbour, Braxton, Greenbrier, Hancock, Jackson, Marshall, Mineral, Preston, Putnam, Ritchie, Roane, Tyler, Webster. WYOMING: Goshen. (Complete label data given in Appendix 1).

Types.

not examined. This species has been well characterized in the literature by authors such as Horn and LeConte.

Natural history.

Label data: underside of fungusy, dead log at night (MB), on piece of cut wood at night (MB), fungusy stump of Acer negundo (MB), bracket fungus (ON), in rotting Pleurotus (QC), on trunk of dead Ulmus americana (QC), under bark of dead maple (QC), under bark of rotting trunk of Pinus eliottii with polypore fungi (Bahamas), ex Fomes on Salix (Bahamas), under bark of Fagus (AR), Trametes versicolor (AR), Meripilus giganteus (AR), polypore tree fungus (AR), under rotting oak bark (CT), in litter at base of dying Ailanthus (CT), large orange polypore shelf fungus [? Polyporus sulphureus ] on standing tree trunk (CT), Omphalotus olearius (CT), under bark (DE), shelf fungi (FL), Griffolia fungus (FL), Polyporus hypnoides (FL), Polyporus sulphureus (FL, MA), under bark of dead pine (FL), hibernating under bark, (GA), under bands of tar paper on apple trees (IL), Armillariella mellea (GA), Pleurotus ostreatus (IL), on shelf fungi (KS), in sweetgum stump (LA), Polyporus adustus (LA), Panus rudis (MA, NJ), under bark of dead Pinus virginiana (MA), under bark dead standing Quercus (MA), in Peromyscus nest debris under bark dead standing Liriodendron (MA), under bark of stump of Prunus serotina (MA), fungus on bark (MS), injured cypress (NC), oak (NC), under bark dead standing pine (NC), under oak bark (NC), Pleurotus sp. (NC, OK), in mushroom (NC), Trametes hispida (ND), under hardwood bark (NJ), ex fungus on Mimosa stump (NJ), on polypore on dead Quercus (TX), polypore fungus (UT), Polyporus squamosus (VT), under poplar bark (WI). Weiss and West (1920) recorded Eustrophopsis bicolor from Pleurotus , Polyporus , Poria , Lentinus and Daedalia . Chantal (1985) provided some details on fungal habitats on/in which adults were collected: Pleurotus sapidus , Polyporus squamosus , Polyporus betulinus , Polyporus versicolor , Polyporus confragosa . Chantal (1985) and Pollock (2008) observed that individuals of this species are often collected together with adults of Synstrophus repandus in the same microhabitats.

Notes.

According to LeConte (1873: 335), "the proper authority for this species is Say, its first describer; Mycetophagus bicolor Fabr. is probably a Platydema ." Pollock (2008) mentioned that no other reference to Say being the author of this species could be found, and in fact, Say himself (1826) considered Fabricius to be the correct author.

Taxonomically, the separation of southern specimens of Eustrophopsis bicolor from those of Eustrophopsis indistinctus proved to be the most difficult problem in this study. Specimens of Eustrophopsis bicolor from northern and eastern North America are very distinctive from the southern specimens of Eustrophopsis indistinctus (color and dorsal punctation). However, as the ranges approach one another, distinguishing features between individuals of the two species become somewhat less conclusive.

Analysis of the male genitalia has revealed several consistent differences between Eustrophopsis bicolor (Figures 57, 63) and Eustrophopsis indistinctus (Figures 59, 64), as follows: 1) tegmen relatively narrow in Eustrophopsis bicolor , with apical and basal piece subequal in length; relatively wider in Eustrophopsis indistinctus , with apical piece distinctly shorter than basal piece; 2) basal struts of median lobe long and narrow in Eustrophopsis bicolor , while shorter and wider in Eustrophopsis indistinctus ; and 3) ring-like portion of sternite 9 U-shaped in Eustrophopsis bicolor , while Y-shaped in Eustrophopsis indistinctus (i.e. with a short basal extension).

There appears to be a rather narrow zone of sympatry between the two species, e.g. Roosevelt County, New Mexico and Randall County, Texas. Hybridization may be occurring in the southwestern United States; for example, multiple specimens from Hidalgo County, Texas seem to exhibit a combination of features of both species. Future studies using molecular methods may be fruitful in “fine-tuning” relationships between Eustrophopsis bicolor and Eustrophopsis indistinctus .