Griburius lecontii Crotch, 1873

Sassi, Davide, 2023, Revision of the Griburius scutellaris (Fabricius, 1801) species group (Coleoptera: Chrysomelidae: Cryptocephalinae), Zootaxa 5315 (6), pp. 501-548 : 529-532

Griburius lecontii Crotch, 1873

( Figs 8 ; 13a–b )

Griburius lecontii Crotch, 1873a: 32 (original description); Crotch, 1873b: 96 (catalogue); Clavareau, 1913: 90 (as G. lecontei, catalogue); Riley et al., 2003: 154 (catalogue); Clark et al., 2004: 139 (biological notes); Niño-Maldonado et al., 2016: 104 (catalogue).

Griburius cyclops Crotch nomen nudum. A single specimen in MCZ ♁, pinned, is labelled: // “Tex.” [white label, printed] // “ Griburius cyclops Type Cr.” [white label, handwritten] // “ cyclops Crotch Type ” [white label, handwritten] // “MCZ TYPE 35252” [red label, partly handwritten] //. There is no evidence for this name to have ever been published. For this reason, this epithet must be considered nomen nudum ( ICZN, 1999, Art. 12). However, the specimen is a male of G. lecontii lacking the usual yellow band on the pronotal anterior margin, which is a chromatic variation already seen in a few other specimens of the species.

Types. Crotch (1973a) did not mention the number of the studied specimens of Griburius lecontii , but at MCZ five specimens are housed, which can be considered syntypes. To stabilize the epithet, the typification was made as follows. LECTOTYPE (by present designation): ♀, pinned, // “Tex.” [white label, printed] // “ J. L. Leconte Coll. ” [white label, printed] // “Type” [white label, printed] // “4 5045” [red label, handwritten] // “ Griburius lecontii Crotch, 1873 LECTOTYPUS D. Sassi des.” [red label, printed] // ( MCZ). Paralectotypes: all paralectotypes labeled as follows; “ Griburius lecontii Crotch, 1873 PARALECTOTYPUS D. Sassi des.” [red label, printed] .

Type locality. Texas .

Additional material examined. (46 specimens). MEXICO: NUEVO LEÓN: Santiago 21.V.2020 & 22.IV.2020 (3, GBIF) ; Monterrey 14.III.2020 (1, GBIF) . TAMAULIPAS: Nacimiento del Rio Sabinas 26.III.1980 (1, ERPC) ; Tamps [Tamaulipas] 8 mi W Jct. hwy 80 & 85 19.VI.1983 (1, ERPC) . U.S.A.: LOUISIANA: East Baton Rouge Par. : Baton Rouge, LSU 1.VI.1985 collected mercury vapor & blacklight (2, ERPC) . OKLAHOMA: Cleveland Co.: Norman 21.VII.2020 (1, GBIF) . TEXAS: Bexar Co.: San Antonio 19.III.2020 & VII.2021 (2, GBIF) . Blanco Co.: Blanco Little River Ln 17.VI.2020 (1, GBIF) . Burleson Co.: Big Creek Park Lake Somerville 16.III.1971 (1, TAMU) . Burnet Co.: Inks Lake State Park 12.VI.1972 at light Ashe (1, TAMU) . Cameron Co.: 1.VI.1961 (1, BYU) ; Laguna Atascosa NWR (site 1) dense coastal brush (1, TAMU) ; Sabal Palm Grv 26.V.1979 (1, TAMU) ; Sabal Palm Grove Audubon Reserve 26.V.1879 (2, FIMU) ; nr. Southmost Sabal Palm Grove Sanct ex blacklight trap 21.V.1981 (1, TAMU) ; Brownsville 20.VI.1969 light trap (1, TAMU) . Comal Co.: SH-46, Spring Branch 2.VI.2019 & 14.VI.2020 (2, GBIF) . Cottle Co.: Matador Wildlife Management Area 29.V.2020 (1, GBIF) . Dimmit Co.: Chaparral Wildlife Management Area 16.III.2000 (1, TAMU) . Hays Co.: Greater Austin Dripping Springs 20.V.2020 (1, GBIF) . Hidalgo Co.: (2, TAMU & BYU) ; Santa Ana Nat. Wdlf Refuge 2.V.87 (1, ERPC) ; Santa Ana NWR (site 3) Wildlife drive Lindgren FT 6.IV.2009 (1, TAMU) ; Ana Nat Refuge 3–9.V.1978 (4, TAMU & FIMU) ; Delta Lake County Park 27.III.1986 (2, ERPC) ; Bentsen Rio Grande Valley State Park 13.III.1980 (1, TAMU) ; Bentsen Rio Grande Valley State Park (site 1) 7.VI.2009 cedar elm (1, TAMU) ; Bentsen Rio Grande Valley State Park 7.IV.1991 (1, TAMU) ; Lower Rio Grande Valley NWF McManus Unit 26.05380°N 98.04987°W 28.III.2009 ebony-guayacan association (11, TAMU) ; Emerald Point 13.III.2021 & 26.III.2021 (2, GBIF) . Kenedy Co.: near Sarita 15.IV.1991 (1, TAMU) . Kerr Co.: Kerrville 2.IV.2008 (1, TAMU) . Liberty Co.: Liberty 9.V.2022 (1, GBIF) . Live Oak Co.: env Dinero (site 9) Twin Oaks Ranch 21.IV.2007 (3, ERPC) . Madison Co.: Madisonville 8.V.1961 (1, TAMU) . Mills Co.: Timberlake Biological Field Station 11.VI.2021 (12, GBIF) ; Lometa 18.V.2019 (1, GBIF) . Nueces Co.: Rosedown Dr Corpus Christi 11.VI.2021 (1, GBIF) ; Northwest Corpus Christi 10.VII.2020 (1, GBIF) . Starr Co.: 28.III.1959 (1, TAMU) ; Santa Margarita Ranch 9.IV.1994 UV (1, ERPC) . Tom Green Co.: San Angelo State Park 8.V.2022 (1, GBIF) . Travis Co.: Austin Windsor Park 11.VI.2021 (1, GBIF) . Schleicher Co.: Eldorado 19.V.1985 (1, TAMU) . Uvalde Co.: Garner St. Park 6.V.1961 (1, TAMU) . Val Verde Co.: Devils River Dolan Falls 12.VI.2000 (1, TAMU) . Wichita Co.: Wichita Falls 10.V.2022 (1, GBIF) . Williamson Co.: Taylor 23.VI.1961 (1, TAMU) . Zapata Co.: San Ygnacio 18.III.1994 at light Chamberlain (2, TAMU) .

Distribution. Mexico (Nuevo León, Tamaulipas). U.S.A. (Texas, Louisiana, Oklahoma). Niño-Maldonado et al. (2016) reported this species from central Mexico (Morelos State). This record needs additional confirmation, in my opinion.

Diagnosis. As a chromatic pattern, the most similar species is G. albilabris . From the latter G. lecontii is distinguished by its almost always dark unicolour legs (black or more rarely dark brown), in the upper lobes of the eyes in the males basically in contact along the median line, in the completely yellow frons in the females. In addition, the punctation on the pronotal surface is usually more developed and denser, and the aedeagal median lobe is dorso-ventrally flattened, recalling the form in G. montezuma . The latter also shares with G. lecontii the arrangement of the ocular upper lobes in males, which are very close along the midline, in contrast to the other species of the group. That might suggest a particular closeness of the two taxa, despite the different dorsal chromatic pattern. In G. lecontii , the duct of the spermatheca is slightly thicker than in the other species, and the turns are arranged in a characteristic way, since they rise along the side of the vasculum keeping close to its proximal lobe up to its upper limit, while in the other species the turns tend to develop below the vasculum or run along the proximal lobe only for less the half of its length.

Description of male. BL = 4.2–4.6 mm, BW = 2.5–2.8 mm, PL = 1.6–1.8 mm, PW = 2.4–2.5 mm. Interocular distance 0.0 % of BL (upper lobes are nearly touching along median line).

Head ( Fig. 8d ) yellow with small triangular area at insertion of antennae and lower rim of clypeus black or brownish. Labrum yellow. Vertex bright, sparsely and very shallowly punctured with short, recumbent, whitish setae. Surface of frontoclypeal area bright as well, with shallow punctation and scattered short setae. Mid-cranial suture short but detectable on anterior part of vertex. Upper lobes of eyes nearly in contact along midline. Ocular lines narrow, barely detectable. Ocular canthus large, not differentiated in punctation from the remainder of frontoclypeal surface, with setosity slightly longer than elsewhere. Antennae ( Fig. 8m ) rather short with antennomeres 2–5 yellowish, bright, subcylindrical; antennomeres 6–11 progressively darkened, dull, more flattened and more diffusedly setose.

Pronotum black with yellow anterior margin. Yellow pattern generally broadened at ends and sometimes extended on anterior half of lateral margins. More rarely yellow pattern missing. Pronotal shape roughly elliptical, scarcely transverse, regularly convex on disc. Lateral margins narrow, not visible from above, regularly curved so that maximum width nearly at middle. Surface moderately shiny usually with close, well-impressed punctation almost evenly distributed, as size and closeness, across whole surface. Posterolateral impressions strongly impressed and obliquely arranged. Pronotal posterior margin thickened along posterolateral impressions.

Scutellum yellow or black, subtriangular with apex shortly truncated. Surface minutely punctured, with few, short setae.

Elytron yellow to chestnut with large transverse black band on posterior half, obliquely extended from lateral margin to suture. Such black band sometimes reaching medially postscutellar area and, posteriorly, elytral apex, so that yellow pattern reduced to anterolateral triangular band. Epipleuron yellow. Elytral outline short with sides almost straight and convergent posteriorly. Lateral margins narrow, simultaneously visible from above only along posterior half. Elytral surface slightly flattened on disc, moderately shiny, with strong punctation arranged in regular rows, well visible up to posterior clivus. Intervals flat. Postscutellar area fairly raised. Humeral callus prominent, impunctate. Epipleuron smooth, impunctate, with convex surface.

Pygidium black. Surface matt, covered with close shallow punctures and appressed, pale setae.

Ventral parts totally black. Hypomera, mesepimera and mesepisterna shiny, with well-impressed, sparse punctures and few, scattered setae. Remainder of ventral surface of thorax and abdomen covered with well-impressed, fine punctures and regularly distributed, sparse, whitish setae. Prosternal process large, with sides almost straight between anterior coxae, then converging in large, round apex; surface feebly depressed, covered with coarse, shallow punctures and sparse, long, semi-erect setae. Legs totally black.

Median depression on fifth abdominal ventrite very shallow and hardly detectable, barely differentiated in punctation and setosity from remainder of ventrite surface. Ventrite posterior margin straight. Median lobe of aedeagus ( Fig. 8g –k ) with apex rather long, triangular, terminated with blunt median denticle. Aedeagal shaft strongly flattened dorsoventrally, with apex almost straight in lateral view. Ventral surface smooth, devoid of special modifications. Setose depressions reduced to tufts of curved setae along base of aedeagal apex.

Female. Habitus in Fig. 8a–b (LT). BL = 4.6–5.3 mm, BW = 2.9–3.4 mm, PL = 1.7–1.9 mm, PW = 2.5–2.9 mm. Interocular distance 8.7–9.4 % of BL.

Females are larger with eyes ( Fig. 8c ) smaller and well separated along the midline. The head surface is matt, more rugulose than punctured, with appressed, sparse, whitish setosity above all on the lower part of frontoclypeal surface. Head is mostly yellow except for vertex and a transverse band between the antennal insertions, which are black. Additionally, the yellow pronotal pattern is missing.

The fifth abdominal ventrite in females has a large, rounded and deep pit. The bottom of the pit is glabrous, matt, impunctate but covered by tiny wrinkles. The vasculum of the spermatheca ( Fig. 8n ) is scarcely pigmented, sickle-shaped with slightly swollen proximal lobe. The distal lobe is long, slender, tapered with a rather acute apex fairly bent downwards. The ampulla is not pigmented, moderately lengthened. The duct insertion on the ampulla is very short and not pigmented. The sperm gland insertion is longer and almost straight. The duct is uniform in size, thick, not coiled with a series of large turns nearly at middle of its length. The insertion on the bursa copulatrix is simple, neither swollen nor pigmented.

Figures

FIGURE 8. G. lecontii. a–b: habitus, dorsal and lateral view (LT); c: frontal view, female (LT); d: frontal view, male (Hidalgo Co., Texas); e–f: colour variations (e: female, Bentsen Rio Grande Valley State Park, Texas; f: female, Dolan Falls, Texas); g–k: median lobe of aedeagus in ventral (g), dorsal (h) and lateral (k) view [0.6 mm]; m: antenna [1.2 mm]; n: spermatheca [0.4 mm]. hd: setose depressions. Square brackets: length of scale segment. Photos a, b and c thanks to the courtesy of Charles Farnum (MCZ).

FIGURE 13. Distribution maps for the Griburius scutellaris species-group. a: G. lecontii, Mexican range; b: G. lecontii, U. S. range; c: G. montezuma, Mexican and Central American range; d: G. montezuma, U. S. range; e: G. rileyi; f: G. scutellaris. Black markings: data from specimens analyzed during the study. Red markings: data from the public database Global Biodiversity Information Facility (GBIF.com) or literature data. Black stars: the presence in the state is reported in the consulted literature, but without more precise data on the location.