Aporotritoma pulchra, Pecci-Maddalena & Skelley, 2021

Pecci-Maddalena, Italo Salvatore de Castro & Skelley, Paul E., 2021, Toward a Natural Classification of Tritomini: Are There Hidden Tribes within the Genus Tritoma Fabricius (Coleoptera: Erotylidae)?, The Coleopterists Bulletin 75 (3), pp. 629-641 : 631-634

ApOROtRItOMa pulchRa (Say, 1826) , new combination

( Figs. 1–2 )

Tritoma pulchrum Say 1826 (1825–1826): 301.

Tritoma cincta Lacordaire 1842: 223 [not Tritoma cincta Arrow 1925: 135 , now Ortitma saggitae ( Boyle 1955: 544) ]. Boyle 1956: 126 [synonym of Tritoma pulchra ].

Tritoma dimidiata Lacordaire 1842: 224 . Boyle 1956: 126 [synonym of Tritoma pulchra ].

Tritoma basale Melsheimer 1847: 175 . Boyle 1956: 126 [synonym of Tritoma pulchra ].

Mycotretus pulchra (Say, 1826) . Crotch 1873: 354 [generic combination].

Mycotretus pulcher (Say, 1826) . Kuhnt 1911: 52 [misspelling].

Tritoma sellata Kuhnt 1910: 247 . Boyle 1956: 126 [synonym of Tritoma pulchra ].

Tritoma pulchra Say, 1826 . Boyle 1956: 126; Roberts 1958: 259; Martin et al. 1981: 140; Skelley 1988: 120; Goodrich and Skelley 1991: 35; Goodrich and Skelley 1994: 292; Goodrich and Skelley 1995: 148, 150; Goodrich 1997: 141; Goodrich and Springer 1999: 53; Robertson et al. 2004: 175; Majka 2007: 41 ; Skelley 2009: 4; Epps and Arnold 2010: 778; Webster et al. 2012: 172.

Diagnosis (n = 4). Body small (3–4 mm), subtriangular, widest at the base of elytra, glossy ( Figs. 1A–C ). Head: Antennal club with 3 antennomeres, antennomeres IX–XI distinctly transverse; epistomal apex weakly concave to truncate, complete clypeal marginal bead present ( Fig. 1D ); postmandibular lobes conspicuously developed, their lateral edges overlapping inner edges of eyes ventrally (similar to those of Triplax festiva Lacordaire and Eudaemonius tuberculifrons (Lewis) ; Fig. 2A , arrow). Mouthparts ( Figs. 1E–H ):Apical maxillary palpomere slightly asymmetrical, transverse-triangular ( Fig. 1E ); lacinia with a pair of hooks, with a V-shaped and narrowed separation ( Figs. 1E–F , arrow, similar to those of Mycotretus Lacordaire , Laurenticola Philipp , Triplax Herbst , etc.); apical labial palpomere slightly dilated medially; mentum elongate-pentagonal, latero-anterior corners not angulated and moderately rounded ( Fig. 1G ); mandibles with outer edge angulated ( Fig. 1H , arrow). Thorax: Procoxal lines conspicuous, forming a distinct elongate-triangular plate extending from the posterior edge of prosternal process to the middle point of anterior prosternal edge ( Fig. 2A ); metendosternite well-developed ( Fig. 2B ), laminae present, anterior tendons thin, moderately separated on anterior portion; metathoracic wings developed, apparently functional, vein rp-mp2 only slightly longer than vein r3. Genitalia. Male ( Figs. 2C–G ): Internal sac with well-developed flagellum ( Fig. 2C , fla), approximately 1.25× as long as penis; flagellar head laterally hook-like, anterior border with two long and strongly sclerotized lobes at middle, U-shaped, widened at base, narrowed apically ( Figs. 2D–E ). Tegmen sclerotized ( Fig. 2F ); outer edge of basal piece with a conspicuous and narrowed projection on each side ( Fig. 2F , arrow); parameres sclerotized, with densely pubescent outgrowths. Laterotergite IX narrowly separated and connected by a short sclerite (spiculum gastrale; Fig. 2G , arrow). Female ( Fig. 2H ): Gonocoxites and gonostyli narrow, elongate; spermatheca strongly sclerotized ( Fig. 2H , spe), distal portion of spermathecal duct strongly sclerotized ( Fig. 2H , spd), large, approximately as long as spermatheca.

Examined Specimens. For diagnoses and illustrations, 2 males and 2 females dissected ( CELC) with label data “ OKLAHOMA: Latimer Co, III– 1987, Karl Stephan [printed]” .

Type Specimen. According to Boyle (1956), the type specimen of Tritoma pulchra was presumably destroyed with Say’s collection (consumed by various insect pests, see Mawdsley 1993). Because T. pulchra is a well-known species and the only member of Aporotritoma in North America, no neotype is required because there are no current nomenclatural issues to resolve ( ICZN 1999, Article 75.2).

Biological Data. A list of host fungi of A. pulchra can be found in Goodrich and Skelley (1994) and this species appears to be a generalist. Epps and Arnold (2010) reported A. pulchra associated only with Tyromyces chioneus (Fr.) P. Karst. ( Polyporales : Meruliaceae ) in two sites in the Appalachian Mountains and foothills. This fungus species also is reported in northern Asia (Núñez and Ryvarden 1999) and it is possible that it is used by the Japanese species of Aporotritoma , a hypothesis for future verification.

Distribution. Aporotritoma pulchra is widely distributed in eastern North America from Nova Scotia south to central Florida, west to South Dakota and eastern Texas.

Known provinces/states and counties of occurrence: CANADA: New Brunswick – Carleton, Charlotte, Northumberland, Queens, Restigouche, Sunbury, York ; Nova Scotia – Inverness, Victoria; Ontario – Carleton, Chatham-Kent Division, Kenora, Kent, Leeds and Grenville United, Niagara, Parry Sound, Waterloo, Wentworth, York;

Quebec – Abitibi-Témiscamingue, Estrie, Montreal, Outaouais. USA: Alabama – Cleburne, Lee, Mobile, Tuscaloosa; Connecticut – Litchfield; District of

Columbia; Florida – Alachua , Leon, Liberty, Orange, Walton ; Georgia – Bibb , Bryan, Clarke, Fulton, Oglethorpe ; Illinois – Champaign, Clark, Coles , Cook , Grundy, Iroquois, Jackson, Wabash ; Indiana – Elkhart, Knox , Lake, Marion, Parke, Tippecanoe ; Iowa – Boone, Linn , Poweshiek, Story, Winneshiek, Woodbury ; Kansas – Doniphan, Shawnee ; Kentucky – [State Record Only]; Maine – Kennebec , York, Lincoln ; Maryland – Frederick , Montgomery, Prince George’s ; Massachusetts – Franklin, Hampden , Hampshire, Suffolk, Worcester ; Michigan – Chippewa, Delta, Grand Traverse, Lake, Leelanau, Marquette, Montmorency, Oakland, Osceola, Saginaw, Wayne ; Minnesota – Becker, Clearwater ; Mississippi – Perry ; Missouri – Boone, Cape Girardeau, Cooper, St. Louis ; Nebraska – Jefferson, Sarpy ; New Hampshire – Carroll, Coos, Grafton , Hillsboro, Rockingham, Strafford, Warren ; New Jersey – Essex, Ocean, Sussex ; New York – Cattaraugus, Earl Island, Erie , Herkimer, Niagara, Tompkins, Westchester ; North Carolina – Buncombe , Orange, Swain, Wake ; Ohio – Butler , Delaware, Fairfield, Franklin, Guernsey , Hamilton , Hocking , Muskogee, Ottawa, Vinton, Wyandot ; Oklahoma – Latimer, Muskogee ; Pennsylvania – Allegheny , Bedford, Bucks, Chester , Delaware, Lackawanna , Northampton, Philadelphia, Pike, Westmoreland ; South Carolina – Pickens, Richland ; South Dakota – Lawrence ; Texas – Erath , Milam, Montgomery, Sabine ; Vermont – Bennington , Washington, Windham ; Virginia – Fairfax , Franklin, Giles, Spotsylvania ; West Virginia – Pocahontas, Fayette, Mercer ; Wisconsin – Bayfield, Milwaukee .

Remarks. Chûjô (1969) mistakenly listed the Japanese species of Aporotritoma under Pseudotritoma Gorham. This error was corrected in the “Catalog of the Erotylidae ( Insecta, Coleoptera ) from the Old World” ( Chûjô and Chûjô 1990).

Aporotritoma pulchra matches the diagnosis of Aporotritoma (= “ Pseudotritoma ”) provided by Chûjô (1969) in possessing apical hooks on the lacinia, a triangular apical maxillary palpomere, narrow tibiae, and a distinct triangular plate formed by the procoxal lines ( Fig. 2A ). After studying the published definitions of Aporotritoma , we conclude T. pulchra is a member of the genus and transfer it from Tritoma to Aporotritoma , becoming Aporotritoma pulchra (Say) , new combination. Within Aporotritoma , A. pulchra is most similar to Aporotritoma consobrina (Lewis) in color pattern.

Figures

Fig. 1. Aporotritoma pulchra, male specimen from Oklahoma: Latimer Co. (USA). A–C) Habitus, D) Head showing clypeal margin. Mouthparts: E) Maxilla, arrow showing lacinial hook, F) Magnified galea and lacinia, arrow points to apical hooks on lacinia, G) Labium, H) Mandible, arrow points to angulate outer edge. Scale bar for A–C = 1 mm, D–E, H = 0.2 mm, F–G = 0.1 mm.

Fig. 2. Aporotritoma pulchra, specimens from Oklahoma: Latimer Co. (USA). A) Ventral head and prosternum showing triangular plate, arrow points to postmandibular lobe, B) Metendosternite. Male and female terminalia: C) Male genitalia, fla = penile flagellum, D–E) Male flagellar head, F) Male tegmen, arrow points to narrowed projection of basal piece, G) Male genital capsule, arrow indicates spiculum gastrale, H) Female genitalia, spe = spermatheca, spd = spermathecal duct. Scale bar for A–B, F–G = 0.2 mm, C = 0.5 mm, D–E = 0.1 mm, H = 0.25 mm.