Agathidium dubitanoides Wheeler and Miller, 2005

WHEELER, QUENTIN D. & MILLER, KELLY B., 2005, Slime-Mold Beetles Of The Genus Agathidium Panzer In North And Central America, Part I. Coleoptera: Leiodidae, Bulletin of the American Museum of Natural History 2005 (290), pp. 1-95 : 69-72

Agathidium dubitanoides Wheeler and Miller , new species Figures 99 , 131

TYPE MATERIAL: Holotype, Ƌ in AMNH (deposited from MTEC) labeled ‘‘MONT: Gallatin Co. Bozeman Crk 6200′ 28 APR 1987 D.L. Gustafson Col./ HOLOTYPE Agathidium dubitanoides Wheeler and Mill­ er, 2002 [red label with black line border]’’.

TYPE LOCALITY: United States, Montana, Gallatin Co., Bozeman Creek.

DIAGNOSIS: This species is nearly identical with A. dubitans except for slight differences

in the endophallus of the aedeagus. In A. dubitanoides the apical, lateral, and basal arms of the median armature are acutely pointed and there is a distinctly pointed tooth between the apical arms (fig. 131), whereas in A. dubitans the arms are short and blunt and there is no tooth between the apical arms or this tooth is short and blunt (fig. 130)

DESCRIPTION: Body elongate oval, strongly dorsoventrally depressed, attenuate posteriorly, weakly contractile; TBL = about 3.2 mm. Color dark reddish­brown; cranium with pale central spot, antenna testaceous, club reddish­brown; pronotum medially slightly paler than elytra, distinctly paler around margins; venter and tibiae reddishbrown, femora testaceous.

Head subquadrate, dorsoventrally flattened, wider than long, OHW/MDL = 1.4; labrum small, transverse, emarginate medially, surface punctate with long, fine setae; frontoclypeal suture present, indistinct; dorsal surface shiny, with moderately dense, irregularly distributed small punctures; area between punctures with irregularly distributed micropunctules; without large punctures behind frontoclypeal suture; eye large, conspicuous, anterolateral, finely faceted; with short postocular temporum, gradually narrowed immediately behind eye, separated from frons by distinct supraocular carina running from lateral margin of clypeal region to posterior margin of cranium; without a larger puncture above each eye; antennomere III longer than IV + V; ratio length II:III = 1: 1.7; VII distinctly longer, slightly wider than VIII, much smaller than IX; ratio width VII: VIII:IX = 1.4:1:1.5; with abrupt 3­segment­ ed club. Pronotum broad, transversely oval, not strongly convex; PNW/PNL = 1.9; PNL/ PNH = 1.3; with very shallow posterior emargination medially; punctures smaller, slightly more dense than those of head, irregularly distributed; area between punctures smooth, shiny, with sparse, irregularly distributed micropunctules. Elytra broadly ovate, SEL/ELW = 1.1 with punctation coarser, but less dense than that of head or pronotum; punctures larger than those of head; with several poorly defined serial rows of punctures, more or less single puncture wide, blending with slightly smaller, irregularly distributed punctures between; smaller punctures sometimes nearly forming parallel series; surface between punctures smooth, shiny, with irregularly distributed, sparse micropunctules; sutural stria impressed in apical three­fourths; area between sutural striae elevated as slight median ‘‘carina’’; sutural stria confluent with suture before apex; humeral angle broadly rounded. Mesosternum relatively large; anterior portion with weak longitudinal median carina, surface alutaceous, subdivided by oblique line. Metasternum with small, moderately dense, setose punctures; surface between densely, finely alutaceous to imbricate.

Male tibia 5–5–4; with pro­ and mesobasotarsomeres enlarged, with spatulate setae beneath; left mandible without tusk; metafemur with apical posterior tooth, relatively small, broad, not well defined, more or less defined by apical angle of femur; metasternal fovea minute, punctiform, anteromedial. Aedeagus elongate, narrow, ventrally curved; median lobe narrowed at apex, apex sharply ventrally curved, with lateral pectinate pattern of apical ducts, with minute serrations in lateral view; lateral lobe attains base of operculum, apex expanded, abruptly spatulate in lateral view, compressed in ventral view; operculum bifurcate, lobes bluntly rounded apically; endophallus with conspicuous medial armature with apically, basolaterally, and basally directed arms which are acutely pointed, with distinct, pointed tooth between apical arms (fig. 131).

Female not examined.

ETYMOLOGY: This species is named from the word dubitans and the suffix ­ oides for the great similarity between this species and A. dubitans .

DISTRIBUTION: This species is known from Montana and Idaho (fig. 99).

PARATYPES: UNITED STATES: Idaho: Cassia Co.: Howell Canyon, 20 Jun 1976, under fir bark, RD Allen (1, PECK). Montana: Gallatin Co.: Bozeman Crk, 25 Jul 1989, 6000′, funnel trap, DL Gustafson (1, MTEC).

DISCUSSION: A single elevation record is from 6000 ft.

Agathidium omissum Fall

Figures 100 , 132–140

Agathidium omissum Fall, 1934: 113 .

Agathidium conjunctum, Hatch ; 1957: 36 (misidentification).

TYPE MATERIAL: Holotype, Ƌ in MCZC labeled ‘‘Glac. Pk Mont. 10Jy 29/ Cut Bank E. Mank/ Ƌ/ NB.2. p.334 [handwritten]/ TYPE omissum [‘TYPE’ underlined in red, ‘omissum’ handwritten]/ M.C.Z. Type 24040/ Agathidium omissum Fall [handwritten, red line around label]/ H.C. FALL COLLEC­ TION / HOLOTYPE, Agathidium omissum Fall, 1934 [red label with black line bor­ der]’’.

TYPE LOCALITY: United States, Montana, Glacier Park.

DIAGNOSIS: This species is distinguishable from other members of the group by the body broadly ovate (fig. 136), the punctation of the head distinctly larger and less dense than those of pronotum (figs. 132, 133), the elytral punctation not arranged serially, the male metafemoral tooth prominent, pointed, and located subapically, the male without metasternal fovea (fig. 135), and the operculum of the median lobe deeply divided, each half with a large apicolateral hook (fig. 139).

DESCRIPTION: Body broadly elongate oval, pronotum convex, elytra dorsoventrally compressed (figs. 136, 137); TBL = 3.4 mm. Color of pronotum and apex of elytron testaceous, antenna testaceous, concolorous, club slightly darker, appendages reddishbrown, head, base of elytron, ventral surface darker, nearly black.

Head subquadrate (fig. 136) with dorsal transverse depression near posterior margin; OHW/MDL = 1.4; surface with moderately dense, poorly defined, shallowly impressed, irregularly distributed punctures (fig. 132), surface between punctures alutaceous; eye large, conspicuous, forming anterolateral angle of head, facets fine; postocular temporum short, less than 0.5X eye length; OHW/PHW = 0.9; anterior marginal carina distinct, from clypeus to postocular temporum; with abrupt 3­segmented club; antennomere III elongate, narrow, twice as long as II; II:III = 1:2; VII and VIII short, transverse; width VII:VIII:IX = 0.9:1:1.8; frontoclypeal suture absent; labrum small, narrow, emarginate medially of apical margin separated from clypeal region by wide membrane. Pronotum broad, convex, anterior margin deeply emarginate to receive head, base of emargination nearly straight; posterolateral angles not defined, obtusely rounded; surface with punctures smaller than those of head, separated by about 1–3X diameter individual puncture, more distinctly impressed than punctures of head (fig. 133), surface between punctures shiny, with microscopically nearly invisible alutaceous pattern. Elytra with narrow plicate margin extending to apex; sutural stria impressed in apical three­fourths, area between sutural striae elevated; elytral surface with dense, poorly defined punctures separated by about 1–2X individual puncture diameter (fig. 134); without serial arrangement of punctures; surface between punctures alutaceous; epipleuron narrowed, ending before apex; ELW/SEL = 0.8. Mesosternum large; anterior portion with median carina, surface densely alutaceous, subdivided by oblique line; posterior part with oblique lateral ridges, surface alutaceous. Metasternum large; with very slight, short trace of oblique lines, surface densely alutaceous; MSL/MTL = 1.1; MTL/MTW = 0.3.

Male tarsi 5–5–4; with pro­ and mesobasotarsomeres expanded with dense spatulate setae beneath; left mandible without tusk; metafemur with large, prominent, pointed, subapical tooth; metasternal fovea absent (fig. 135). Aedeagus robust, elongate; medi­ an lobe sinuate in lateral view, curved from base toward apex first ventrally then dorsally (fig. 138); in ventral aspect gradually narrowed then abruptly narrowed in apical fifth (figs. 139, 140), apex with dense, irregularly distributed ducts in fanlike pattern (figs. 139, 140); operculum divided entirely in apical half, partially in basal half, apex of each process in form of asymmetrical, laterally produced and recurved hook, with sparse, irregularly distributed pores on apical half (fig. 139); lateral lobes gradually narrowed, apices slightly clavate, with 2 setae, 1 apical, 1 genitalia, his concept of A. conjunctum appears to be the same as ours of A. omissum . This may have led to his description of a new species ( A. obtusum Hatch ) for specimens that we regard to be A. conjunctum (see below under treatment of A. conjunctum ).

This species has been collected from ‘‘squirrel middens under conifer’’ and elevations from 7700 to 9300′.

subapical, with sparse, irregularly distributed pores (figs. 138, 139).

Female unknown.

DISTRIBUTION: This species occurs in the central and southern Rocky Mountains (fig. 100).

SPECIMENS EXAMINED: CANADA: British Columbia: Midday Valley, Merritt , 14 May 1925, Pinus ponderosa, J Stanley (1, CASC) ; Monashee Mtn nr. Cherryville , 11 Aug 1982, 1400′, M Sorenson (2, LUND) .

UNITED STATES: Colorado: Eagle Co.: 5 mi E Avon, 25 May 1986, 7500′, M Sorenson (2, LUND) ; Grand Co.: 9 mi SE Jct US 40 and CO 14, 21 Jun 1975, 7700′, squirrel middens under conifer, A Newton, M Thayer (1, FMNH). Idaho: Twin Falls, Magic Mt, 15 May 1976, AD Miller (1, FMNH). New Mexico: Bernalillo Co.: 10 mi E Albuquerque Sandia Mt, Capulin Spg , 21 Aug 1975, 9300′, S Peck (1, CUIC) .

DISCUSSION: Based on Hatch’s (1957: pl. IV, fig. 20) key and illustration of the male

Figures

Fig. 99. Geographic distribution of Agathidium revolvens group species: A. depressum Fall = •; A. dubitanoides, n.sp. = *; A. dubitans Fall = ·; A. jasperanum Fall = ^.

Figs. 128–131. Agathidium revolvens group species: Figs. 128–130, A. dubitans Fall, aedeagus: 128, lateral; 129, ventral; 130, apex of median lobe and armature of endophallus, ventral aspect. 131. A. dubitanoides, apex of median lobe and armature of endophallus, ventral aspect.

Fig. 100. Geographic distribution of Agathidium revolvens group species: A. cavisternum Fall = ·; A. falcatoperculum, n.sp. = •; A. revolvens LeConte = *; A. omissum Fall = ^.

Figs. 132–137. Agathidium omissum Fall: Figs. 132–134, punctation details: 132, head; 133, pronotum; 134, elytron. 135. Male metasternal fovea. Figs. 136, 137, habitus: 136, dorsal; 137, lateral. Bars = 0.5 mm.

Figs. 138–140. Agathidium omissum Fall, aedeagus: 138, lateral; 139, ventral; 140, apex of median lobe.