Agathidium akallebregma 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 : 11-14

Agathidium akallebregma Miller and Wheeler , new species Figures 3 , 31, 32 , 41

TYPE MATERIAL: Holotype, Ƌ in CASC labeled ‘‘ CALIF: Kern Co. 5 mi. SE Tehachapi XI­9­1984 AJ Gilbert Berlese Oak­Pine duff/ HOLOTYPE Agathidium akallebregma Miller and Wheeler, 2003 [red label with black line border]’’.

TYPE LOCALITY: United States, California, Kern Co., 5 mi SE Tehachapi.

DIAGNOSIS: This species differs from others in this group by the sunken clypeus and raised lateral areas of the frons and the shape of the median lobe of the aedeagus, which has the apex slightly dorsally hooked and narrowly rounded in lateral aspect (fig. 32). The operculum is broad, hyaline, and apparently fused to the median lobe basally (fig. 31).

DESCRIPTION: Body moderate to large (TBL = 2.17–2.64 mm), elongate (PNW/ TBL = 0.53–0.48), moderately contractile.

Head dark red; pronotum, elytra, and venter red to dark red; mesosternum yellow; basal antennomeres, palpi, and legs red­brown, antennomeres of club dark brown.

Head very broad (fig. 3) (MDL/OHW = 0.54–0.61), convex, with moderately prominent, transverse, medial crease; temporum prominent in dorsal aspect, 1.0 times eye length, laterally protuberant beyond level of eye in anterior portion (fig. 3); head finely and sparsely to moderately densely punctate, some specimens with interspersed micropunctules, surface between punctures shiny, a few specimens with indistinct, fine microreticulation; eyes large, rounded, finely faceted; frontoclypeal suture indistinct medially; clypeal margin strongly excavate (fig. 3); anterior margin of labrum entire; clypeus impressed with frons around clypeus irregularly raised, especially laterad of clypeus above antennal insertions, making anterior surface of cranium very irregular, most conspicuous in male; antennomere ratios: length I:II:III = 2.2:1.0:1.2, width VII:VIII:IX = 1.0:1.0:1.3. Pronotum broad (PNL/PNW = 0.52–0.59), laterally not strongly produced, anterolateral angle subquadrate to rounded, posterolateral angle distinctive, but somewhat more round­ ed than anterolateral angle; punctation similar to that of head, slightly more dense. Elytra moderately elongate (SEL/ELW = 0.91– 0.92); punctation coarsely and densely punctate, with larger punctures and many small micropunctules interspersed, some coarse punctures forming irregular longitudinal series; sutural stria about one­half length of elytron on most specimens. Mesosternum concave posteriorly, without prominent lobe extending ventrally between mesocoxae, anterior portion about one­half length of posterior portion; medial longitudinal carina absent on anterior portion. Metasternum broad medially (MTL/MTW = 0.30–0.31), slightly convex, setose; oblique carinae absent.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres moderately broad and with moderately large ventral field of spatulate setae; mandibular modification present in both males examined, apex of mandible broadly expanded and truncate; metafemur moderately slender, unmodified; metasternal fovea large, anterior, transversely oval with large brush of long, fine, dense setae. Median lobe of aedeagus in lateral aspect large, moderately robust, with robust, expanded basal portion and submedially constricted, apical portion narrowed to fine, slightly dorsally directed point (fig. 32); in ventral aspect moderately broad, lateral margins slightly convergent apically, apical portion broadly triangular, apex pointed, orifice very large (fig. 31); operculum consisting of a triangular, hyaline lobe (fig. 31); endophallus with prominent, long, medial spine visible in orifice (fig. 31); lateral lobes long, slender, curved basally, apices narrowly rounded with 2 long setae (figs. 31, 32).

Female tarsi 5­4­4.

ETYMOLOGY: Named from the Greek words akalles, meaning ‘‘ugly’’, and bregma, meaning ‘‘face’’, for the unusually shaped anterior portion of the head in this species.

DISTRIBUTION: This species is known from only two localities in California and Oregon (fig. 41).

PARATYPES: UNITED STATES: California: Kern Co.: 5 mi SE Tehachapi, 8 Nov 1984, oakpine duff, AJ Bilbert (3, FGAC). Oregon: Jackson Co.: 7 mi N Ashland, 27 Dec 1971, 3500̍, oak brush duff, E Benedict (1, PECK).

DISCUSSION: This species has been collect­ ed from oak and oak­pine duff. A single elevation record is from 3500 ft.

Agathidium mollinum Fall

Figures 17, 18 , 33, 34 , 41 Agathidium mollinum Fall, 1934b: 128 .

TYPE MATERIAL: Holotype, Ƌ in MCZC labeled ‘‘Wt. Mts. N. H. Woods/Ƌ/ Agathidium politum Lec [handwritten]/M.C.Z. Type 19570 [number handwritten, red label]/Frederick Blanchard Collection/ Agathidium mollinum Fall TYPE [handwritten]’’.

TYPE LOCALITY: United States, New Hampshire, White Mountains.

DIAGNOSIS: Individuals of this species are smaller than those of most species in this group (TBL <2.5 mm). The male mandibular horn varies from small and extending from medial surface of left horn laterad to right over right mandible to very long and extending in broad C­shaped curve to left and back over left mandible (figs. 17, 18). The male metasternal fovea is linear, long, transverse, and submedial. The median lobe of the aedeagus is long and slender in lateral aspect with the apex simple (fig. 34).

DESCRIPTION: Body small to moderately large (TBL = 2.24–2.48 mm), robust (PNW/ TBL = 0.47), moderately contractile.

Head, pronotum, and elytra dark redbrown; venter red­brown to dark brown; basal antennomeres, palpi, and legs red­brown.

Head broad (fig. 18) (MDL/OHW = 0.54– 0.69), flattened, without transverse, medial crease; temporum prominent, about 0.6–1.0 times eye length when viewed in dorsal aspect (fig. 18); head finely and sparsely punctate, surface between punctures shiny, a few specimens with indistinct, fine microreticulation; eyes large, rounded, finely faceted; frontoclypeal suture moderately well defined medially; clypeal margin strongly excavate (fig. 18); anterior margin of labrum entire; antennomere ratios: length I:II:III = 2.0:1.0: 1.5, width VII:VIII:IX = 1.0:1.0:1.9. Pronotum broad (PNL/PNW = 0.54–0.56), laterally not strongly produced, anterolateral angle subquadrate to rounded, posterolateral angle distinctive, but rounded; punctation and surface microsculpture similar to that of head. Elytra moderately elongate (SEL/ELW = 1.14–1.18); punctation similar to pronotum, some punctures in vague linear series, surface between punctures shiny and smooth; sutural stria about one­half length of elytron on most specimens. Mesosternum strongly concave posteriorly, without prominent lobe extending ventrally between mesocoxae, anterior portion less than one­half length of posterior portion; medial longitudinal carina absent on anterior portion. Metasternum broad medially (MTL/MTW = 0.25–0.34), slightly convex, setose; oblique carinae absent.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres moderately broad and with moderately large ventral field of spatulate setae; left mandible in three forms: (1) unmodified, (2) thickened and prominently extending to the right over other mandible, and (3) extremely long, cylindrical and curving broadly to left and back up over mandible (figs. 17, 18), with this last type setose and with prominent apical fovea and cluster of setae; metafemur moderately slender, unmodified; metasternal fovea large, transversely linear and slightly curved, located slightly anterad of middle. Median lobe in lateral aspect moderately slender, slightly curved medially, base not large, apical portion short, narrowed, apically slightly truncated, directed slightly dorsad (fig. 34); in ventral aspect slender, lateral margins subparallel, apical portion subtriangular, apex rounded (fig. 33); operculum short, comprised of two short lobes (fig. 33); lateral lobes broad at base, broadly fused dorsally for about one­half length of median lobe, apically slender and straight, apically pointed with 2 long setae. (figs. 33, 34).

Female tarsi 5­4­4.

DISTRIBUTION: This species is know from eastern North America from Ontario to New Hampshire and Maine south to North Carolina (fig. 41).

SPECIMENS EXAMINED: CANADA: Ontario: 25 km W Ignace , 75 km E Dryden, 5 Jun 1984, firmaple forest, FIT, S and J Peck (2, CNCI) ; Lake Superior Prov. Park , Algoma Co., 9 Sep 1980, R Baranowski (4, LUND) .

UNITED STATES: Maine: ‘‘ Tang Lo’ ’??, Aug 1894 (1, MCZC). Michigan: state only (1, CMNH). New Hampshire: Carrol Co.: 1 mi N Wonalancet, 7 Aug 1985, FIT, DS Chandler (2, CNCI) ; The Bowl , 2.5 mi NW Wonalancet, 2 Jul 1985, FIT, DS Chandler (4, CNCI) ; Coos Co.: 1 mi NE East Inlet Dam , 8 Aug 1986, DS Chandler (1, CNCI) ; Mt Washington auto road, 1 Jul 1982, 2700̍, birch litter, DS Chandler (1, DENH) ; Norton Pool 2 mi E East Inlet Dam, 7 Sep 1984, leaf litter, fallen spruce, DS Chandler (17, CNCI) ; Norton Pool , 3 mi NE East Inlet Dam, 9 Jul 1986, conifer logs, DS Chandler (3, CNCI). New York: Albany Co.: Rensselaerville, E.N. Huyuck Preserve, 18 Aug 1974, birch log, WR Suter (1, PECK) ; Sullivan Co.: Mangoup Lake, 3 mi N Debruce, 22 May 1968, litter, Berlese, S Peck (1, PECK). North Carolina: Jackson Co. : Blue Ridge Parkway, Hayward Gap, 5 Jun 1984, FIT, S Marshall (2, PECK) ; Swain Co.: 14 Sep 1985, 5800̍, on Cribraria purpurea, SL Stephenson (7, CUIC) ; Yancey Co.: Mt Mitchell, 31 May 1973, fern rhizome, WR Suter (1, PECK). Virginia: Giles Co. : 18 Jun 1986, 3700̍, on Stemonitis axifera, SL Stephenson (3, CUIC) ; 6 Oct 1984, on Diderma floriforme, SL Stephenson (1, CUIC) .

DISCUSSION: This species has been collect­ ed from litter from various sources including birch, fir, maple, and ‘‘conifer’’. It has also been collected from ‘‘fern rhizome’’ and in flight intercept traps. Host records include the myxomycetes Cribraria purpurea , Diderma floriforme , and Stemonitis axifera .

Figures

Figs. 3–16. Agathidium concinnum­ and A. pulchrum­group species. 3–15. Heads, dorsal aspect: 3, A. akallebregma. 4, A. hatchi. 5, A. concinnum. 6, A. laetum. 7, A. athabascanum. 8, A. columbianum. 9, A. rusticum. 10, A. repentinum. 11, A. rotundulum. 12, A. atronitens. 13, A. oregonense. 14, A. hamulum. 15, A. politum. 16, A. rusticum, left antenna, dorsal aspect. Bars = 0.5 mm, except fig. 16 bar = 0.25 mm.

Figs. 31–40. Agathidium concinnum­group species, aedeagus: 31, 32, A. akallebregma: 31, ventral; 32, lateral. 33, 34, A. mollinum: 33, ventral; 34, lateral. 35, 36, A. angulare: 35, ventral; 36, lateral. 37, 38, A. hatchi: 37, ventral; 38, lateral. 39, 40, A. concinnum: 39, ventral; 40, lateral.

Fig. 41. Geographic distribution of Agathidium concinnum­group species: A. akallebregma = -; A. mollinum Fall = ^ (Δ = state record only).

Figs. 17–30. Agathidium concinnum­ and A. pulchrum­group species, male heads showing left mandibular horn: 17, 18, A. mollinum: 17, left lateral; 18, dorsal. 19, 20, A. angulare: 19, left lateral; 20, dorsal. 21, 22, A. pulchrum: 21, left lateral; 22, dorsal. 23, 24, A. marae: 23, left lateral; 24, dorsal. 25, 26, A. aristerium: 25, left lateral; 26, dorsal. 27, 28, A. atronitens: 27, left lateral; 28, dorsal. 29, 30, A. picipes: 29, left lateral; 30, dorsal. Bars = 0.5 mm.