Agathidium tumidiventre Miller and Wheeler, 2005

MILLER, KELLY B. & WHEELER, QUENTIN D., 2005, Slime-Mold Beetles Of The Genus Agathidium Panzer In North And Central America, Part Ii. Coleoptera: Leiodidae, Bulletin of the American Museum of Natural History 2005 (291), pp. 1-167 : 126-127

Agathidium tumidiventre Miller and Wheeler , new species Figures 153 , 292–295 , 368

TYPE MATERIAL: Holotype, Ƌ in CMNC labeled ‘‘ MEX: Tamps ; 1000 m nr Gomez Farias 7.VIII.83, S&J. Peck cloudforest litter/ HOLOTYPE Agathidium tumidiventre Mill­ er and Wheeler , 2003 [red label with black line border]’’ .

TYPE LOCALITY: Mexico, Tamaulipas, nr Gomez Farias, 1000 m.

DIAGNOSIS: Members of this species have a relatively small, anteapical male metafemoral tooth (fig. 153), moderately broad metasternum with a low posterior carina where the oblique metasternal carinae meet medially, relatively large, finely faceted eyes, and prominent medial tumidity on the gula. Specimens are generally not iridescent dorsally, though a few are. This is one of several species that are positively identifiable only by dissection of male genitalia. In this species the median lobe has moderately developed dorsal and lateral carinae for reception of the lateral lobes, and the apical portion of the median lobe is evenly curved in lateral aspect (fig. 294) and relatively evenly narrowed to a slightly expanded apex in ventral aspect (fig. 292). The operculum is fairly long and slender and has the apex rounded with a prominent, but shallow, apical emargination (fig. 292). The species is nearly identical to A. aztec , including genitalic shape, except for the lack in that species of a distinct tumidity medially on the gula.

DESCRIPTION: Body moderately large (TBL = 3.40–3.57 mm), broad, robust (PNW/TBL = 0.48), strongly contractile.

Head and pronotum testaceous; elytra testaceous, iridescent; venter yellow­brown, antennae and palpi yellow; legs yellow to yellow­brown.

Head broad (MDL/OHW = 0.57–0.62), dorsal surface flattened, dorsoventrally compressed; with very fine punctures, each with a short, very fine seta, surface between punctures shiny, smooth; frontoclypeal suture obsolete medially; eyes prominent, not compressed; gula with very prominent median tumidity; antennomere ratios: length I:II:III = 2.1:1.0:2.2, width VII:VIII:IX = 1.0:1.0: 1.4. Pronotum very large, broad (PNL/PNW = 0.77), strongly convex, anterolateral lobes strongly produced, lateral margin broadly curved, not angulate; with very fine, sparse punctures, each with a short, very fine seta, surface between punctures smooth. Elytra broad, lateral margins strongly rounded, apically rounded (SEL/ELW = 0.96–0.99); punctation similar to pronotum; sutural stria present in apical one­fifth to one­half of elytron. Flight wings strongly reduced. Mesosternum broad, flattened; medial carina present, but low and not strongly developed. Metasternum relatively narrow (MTL/MTW = 0.13–0.17), flattened, sloping dorsad anteriorly; oblique femoral carinae moderately prominent, low and convex medially.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres slightly laterally expanded, with small ventral field of spatulate setae; mandibles not modified; metafemur moderately broad with posteroapical tooth and series of smaller teeth, apical margin rounded to truncate (fig. 153); metasternal fovea large, transversely oval, medial, with cluster of long, dense, fine setae. Median lobe in lateral aspect moderately slender, moderately long, strongly curved basally, moderately expand­ ed submedially on dorsal margin with moderately developed lateral sulcus for reception of lateral lobe, apical portion of median lobe directed slightly dorsad, straight, slightly expanded medially, apex pointed (fig. 294); in ventral aspect slender, slightly constricted medially, distinctly expanded submedially, apical portion narrowed to constricted neck, thereafter, expanded and apex rounded (fig. 292, 293); operculum long and slender in lateral aspect, apically pointed (fig. 294), in ventral aspect long with lateral margins sub­ parallel, apex distinctly and moderately broadly emarginate (fig. 292); lateral lobes slender, strongly curved basally, sinuate, expanded medially, apex curved and slender to narrowly rounded (fig. 295).

Female 5­4­4.

ETYMOLOGY: This species is named for the Latin words tumidus, meaning ‘‘swelling’’, and ventris, meaning ‘‘belly’’, for the prominent medial tumidity on the ventral surface of the gula.

DISTRIBUTION: This species has been collected from Hidalgo and Tamaulipas (fig. 368).

PARATYPES: MEXICO: Hidalgo: 6.5 mi S Tianguistengo , 7 Jul 1973, 6800̍, on ‘‘gilled mushroom’’, A Newton (1, FMNH) ; Tlanchinol, 43 km SW Huejutla, 14 Jun 1983, 1500̍, cloud forest litter, S and J Peck (5, PECK). Tamaulipas: nr. Gomez Farlas, Rancho del Cielo , 6 Jun 1983, 1000 m, cloud forest, FIT, S and J Peck (6, PECK) .

DISCUSSION: The species has been collect­ ed from cloud forest litter at 1500–6800 ft and from a ‘‘gilled mushroom’’.

Figures

Figs. 145–172. Agathidium oniscoides­group species, left male metafemur, ventral aspect: 145, A. oculeum. 146, A. recurvatum. 147, A. impensum. 148, A. cheneyi. 149, A. tenangoense. 150, A. rumsfeldi. 151, A. hirsutum. 152, A. cortezi. 153, A. tumidiventre. 154, A. aztec. 155, A. iridescens. 156, A. dentigerum. 157, A. stephani. 158, A. akrogeneios. 159, A. appalachium. 160, A. pocahontasae. 161, A. carolinense. 162, A. gallititillo. 163, A. divaricatum. 164, A. bushi. 165, A. georgiaense. 166, A. chauliodoum. 167, A. microphthalmum. 168, A. nimbosilva. 169, A. oniscoides. 170, A. rubellum. 171, A.

Figs. 288–302. Agathidium oniscoides­group species, aedeagus: 288–291, A. cortezi: 288, ventral; 289, median lobe, apex, ventral; 290, median lobe, lateral; 291, left lateral lobe, lateral. 292–295, A. tumidiventre: 292, ventral; 293, median lobe, apex, ventral; 294, median lobe, lateral; 295, left lateral lobe, lateral. 296–298, A. aztec: 296, ventral; 297, median lobe, lateral; 298, left lateral lobe, lateral. 299–302, A. iridescens: 299, ventral; 300, median lobe, apex, ventral; 301, median lobe, lateral; 302, left lateral lobe, lateral.

Figs. 367, 368. Geographic distribution of Agathidium oniscoides­group species: 367, A. hirsutum = -; A. tenangoense = •; A. iridescens = ^; A. rumsfeldi = *. 368, A. aztec = ^; A. cortezi = *; A. tumidiventre = •.