Agathidium angulare Mannerheim, 1852

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 : 14-19

Agathidium angulare Mannerheim Figures 1 , 19, 20 , 35, 36 , 42

Agathidium angulare Mannerheim, 1852: 369 ; Horn, 1880; Leng, 1920; Fall, 1934b.

Agathidium assimile Fall, 1934b: 128 . NEW SYN­ ONYM.

Agathidium temporale Fall, 1934b: 127 (preoccupied by Sahlberg, 1908, replaced by Fall, 1934a).

Agathidium municeps Fall, 1934a: 171 (replacement name for Agathidium temporale Fall, 1934b nec Sahlberg, 1908). NEW SYNONYM.

Agathidium falli Hatch, 1957: 32 (unnecessary replacement name for Agathidium temporale Fall, 1934b nec Sahlberg, 1908). NEW SYNONYM.

TYPE MATERIAL: Agathidium angulare : lectotype (designated here to fix this name

with this species), Ƌ in MCZC labeled ‘‘93/ Type 7946 [red label]/ A. angulare Sitkha Mannh. [handwritten]’’. Horn (1880) and Fall (1934b) each mentioned multiple type specimens, and Mannerheim (1852) seemed to imply he had more than one specimen when he described this species. We selected the male specimen in MCZC as the lectotype.

Agathidium assimile : holotype, Ƌ in MCZC labeled ‘‘Ind./Ind’apolis 7/14/10/Ƌ/ TYPE assimile [name handwritten, red line under ‘‘TYPE’’]/M.C.Z. Type 19571 [number handwritten, red label]/H.C. FALL COL­ LECTION.’’ There are three paratypes (one male, two females) from Mt. Washington, New Hampshire.

Agathidium temporale : holotype, Ƌ in MCZC labeled ‘‘Randolph Hill. N.H. ’04­IX J.D.S. [handwritten]/Ƌ/near difforme clypeal [handwritten, with other words illegible]/Tarsi 5­5­4 [handwritten]/M.C.Z. Type 19573 [number handwritten, red label]/Frederick Blanchard Collection/ Agathidium temporale Fall TYPE [handwritten]/replacements: municeps Fall ’34 falli Hatch ’57 [handwritten]/ Agathidium temporale Fall [handwritten, red line around border]’’. There is one female paratype from North Conway, New Hampshire.

TYPE LOCALITY: Agathidium angulare : United States, Alaska.

Agathidium assimile : United States, Indiana, Indianapolis.

Agathidium temporale : United States, New Hampshire, Randolph.

DIAGNOSIS: This species is diagnosed by its relatively large size (TBL> 2.5 mm), long male mandibular horn (when present and fully developed) that extends from the medial surface of the mandible in a moderate, oblique curve up and to right over the clypeus (figs. 19, 20), and male with the median lobe of the aedeagus in lateral aspect stout, curved, and with the apex abruptly anvilshaped and truncate (fig. 36).

DESCRIPTION: Body moderate to large (TBL = 2.59–3.32 mm), elongate (PNW/ TBL = 0.46–0.49), moderately contractile.

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

Head very broad (figs. 1, 20) (MDL/OHW = 0.62–0.73), convex, without transverse, medial crease; temporum prominent, about 0.6 to 1.0 times eye length when viewed in dorsal aspect (figs. 1, 20); 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 obsolete medially; clypeal margin strongly excavate (figs. 1, 20); anterior margin of labrum entire; antennomere ratios: length I:II:III = 2.3:1.0:1.4, width VII:VIII:IX = 1.1:1.0:2.5. Pronotum broad (PNL/PNW = 0.55–0.57), laterally not strongly produced, anterolateral angle subquadrate to rounded, posterolateral angle distinctive, but rounded; punctation similar to that of head. Elytra moderately elongate (SEL/ELW = 1.01–1.20); punctation coarser than that of pronotum, some specimens relatively densely punctate, others more sparse, some specimens with numerous micropunctules between larger punctures; sutural stria about three­fifths length of elytron on most specimens. Mesosternum strongly concave posteriorly, with 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 = 0.33–0.35), slightly convex, setose; oblique carinae absent.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres moderately broad and with moderately large ventral field of spatulate setae; mandibular horn, when fully developed, very long, curving anteriorly, then posteriorly over front of head (figs. 19, 20), subcircular throughout in cross­section, punctate and setose along its length, apical fovea prominent with large cluster of setae, some specimens with mandible variously thickened, others without modification; metafemur moderately slender, unmodified; metasternal fovea small, round, anterior, moderately large brush of fine, dense setae. Median lobe in lateral aspect large, moderately robust, strongly curved basally with slight constriction, lateral margins evenly converging, apical portion flat, slender, curved dorsad, apex abruptly expanded (fig. 36); in ventral aspect mod­ erately broad, lateral margins subparallel, apical portion triangular, apex pointed, orifice large (fig. 35); operculum long and moderately broad, apically narrowly emarginate, inconspicuous and hyaline (fig. 35); lateral lobes long, slender, curved basally, apices rounded with 2 long setae (figs. 35, 36).

Female tarsi 5­4­4.

DISTRIBUTION: This species is widespread across northern North America from Alaska to New Hampshire and south in western North America to Arizona (fig. 42). Records from Indiana and Arkansas suggest that the species may be even more widespread than records indicate.

SPECIMENS EXAMINED: ‘‘W.T’’ [probably Washington Territory] (1, MCZC).

CANADA: Alberta: Demmitt , 3 km W 90 km NW Grand Prairie, 12 Jun 1984, poplar forest, FIT, S and J Peck (1, PECK) ; 3.8 mi N Cadomin , 4 Aug 1985, lodgepole pine forest, FIT, RS Anderson (40, CNCI) ; Sibbold Flats Rec. Area , 6 Sep 1981, FIT, RS Anderson (10, CNCI) ; George Lake 50 km NW Edmonton, 11 Jun 1984, spruceaspen forest, FIT, S and J Peck (2, CNCI). British Columbia: Pink Mountain 252 km S Ft Nelson, Rt 97, 12 Jun 1984, aspen forest, FIT, S and J Peck (14, PECK) ; Lorna , 17 Aug 1934, R Hopping (1, CASC) ; Mt Robson P Park, Berg Lake Trailhead , 11 Jul 1984, RS Anderson (10, PECK) ; Bear Lake , 20 Aug 1969, sifting, BF and JL Carr (1, CARR) ; 37 km W Ft Nelson, Ak Hwy , 12 Jun 1984, aspen­spruce forest, FIT, S and J Peck (12, PECK) ; Mt Robson P Park, Berg Lake Trailhead , 11 Jul 1984, RS Anderson (44, CNCI) ; 14 km E Coal River, 160 km E Watson Lake , YT, 14 Jun 1984, spruce­alder forest, malaise FIT, S and J Peck (12, PECK) ; 5.6 mi E E Border Glacier Natl Park on #1, 11 May 1984, Columbia forest , RS Anderson (3, CNCI) ; Mount Robson Prov. Park, Berg Lake Trailhead , 4 Jul 1984, cedar/hemlock forest litter, RS Anderson (1, PECK) ; Kootenay Natl Park , 17 Jul 1985, on Stemonitis, SL Stephenson (3, AMNH) ; Pink Mt , 252 km S Ft Nelson, rt 97, 5 Jun 1984, aspen forest, FIT, S and J Peck (10, CNCI) ; Stanley , 19 Jul 1932, N Graham (2, CASC) ; Manning Prov. Park , 19 Jun 1979, alpine meadow, pitfall traps, CD Dondale (20, CNCI) ; Lorna, 19 Jul 1926, H Richmond (1, CASC). Manitoba: Grass River Prov. Park, 100 rd km SE FlinFlon , 7 Jun 1984, pine­aspen forest, FIT, S and J Peck (4, CNCI) ; Grass Riv. Prov. Park, 100 rd KM SE FlinFlon, 7 Jun 1984, pineaspen forest, FIT, S and J Peck (2, PECK). Ontario: Stittsville , 5 Sep 1976, M Sanborne (1, PECK) ; 25 km W Ignace, 75 km E Dryden , 5 Jun 1984, fir­maple forest, FIT, S and J Peck (1, PECK) ; Kemptville , 2 Oct 1984, BRI staff (1, CNCI) ; Gloucester , 15 Sep 1984, M Sanborne (1, CNCI) ; Chaffey Locks QUSB, 5 Oct 1980, forest, malaise FIT, S Peck (16, CNCI) ; Smooth Rock Falls 56 km NW Cochrane, 3 Jun 1984, mixed spruce­birch, evening car netting, S and J Peck (1, PECK) ; Haley Sta. 15 km NW Refrew, 2 Nov 1979, mixed forest, malaise, S and J Peck (1, CNCI) ; Lake Superior Prov. Park , Algoma Co., 9 Sep 1980, R Baranowski (1, LUND) ; 25 km W Ignace, 75 km E Dryden , 5 Jun 1984, fir­maple forest, FIT, S and J Peck (1, CNCI) ; Stittsville, DA Smith’s woods, 18 Oct 1979, forest, malaise FIT, S Peck (3, CNCI). Quebec: Hull, Gatinaeu Park, nr Pinks Lake , 30 Jun 1979, for. Mal. Trough, S Peck, A Davies (5, PECK) ; Gatineau Park nr Pinks Lake , 1 Oct 1979, forest, malaise, S Peck, A Davies (10, CNCI) ; Masham, Lac Philippe, Gatineua , 13 Dec 1981, on Brefeldia maxima, S Peck (21, CNCI) ; Hull, Gatinaeu Park, nr Pinks Lake , 24 Jun 1979, for. Mal. Trough, S Peck, A Davies (7, PECK) ; Masham lac Philip, Gatineau , 13 Sep 1981, reared from larvae, on Brefeldia maxima, S Peck, A Newton (3, FMNH). Saskatchewan: Jay Jay Lake Rt 102, 130 km NE Candle Lake, 8 Jun 1984, pine­fir forest, FIT, S and J Peck (1, CNCI) ; Jay Jay Lake, Rt 102, 130 km NE Candle Lake, 8 Jun 1984, pine­fir forest, FIT, S and J Peck (4, PECK). Yukon: Dawson City, km 45 Kondike Hwy , 9 Jul 1985, cut willow, Equisetum, FIT, SA Marshall (1, PECK) ; Engineer Creek Dempster Hwy, km 194, 19 Jun 1984, spruce­aspen forest, car top, S and J Peck (1, PECK) ; Ross River , 16 Jun 1984, aspen­willow, river terrace, malaise FIT, S and J Peck (9, PECK) ; Dempster Jct 40 km E Dawson, 19 Jun 1984, willow­spruce forest, malaise FIT, S and J Peck (26, PECK) ; Dempster Hwy, Tombstone Mtn Camp , 5 Jul 1985, willow shrub, FIT, SA Marshall (2, PECK) ; km147 Dempster Hwy , 6 Jul 1985, fen willows­spruce dung pan trap, SA Marshall (1, PECK) ; Simpson Lake , 81 km N Watson Lake, 15 Jun 1984, pine­willow forest, malaise FIT, S and J Peck (9, PECK) ; Moose Creek , 14 km NW Stewart Cross., 18 Jun 1984, stream willow thicket, malaise FIT, S and J Peck (20, PECK) ; Dempster Jct 40 km E Dawson, 19 Jun 1984, willow spruce forest, malaise FIT, S and J Peck (1, CNCI) ; Engineer Creek, Dempster Hwy km 194, 19 Jun 1984, willow spruce forest, malaise FIT, S and J Peck (1, CNCI) ; Engineer Creek, Dempster Hwy , km 194, 19 Jun 1984, aspenspruce forest, FIT, S and J Peck (38, PECK) ; Ross River , 16 Jun 1984, aspen willow river terrace, malaise FIT, S and J Peck (6, CNCI) .

UNITED STATES: Alaska: Chatanika Hwy 6, Chatanika River, 13 Aug 1984, floodplain birch forest litter, Berlese, S and J Peck (2, PECK); Houston, 24 Jun 1984, spruce­birch forest with moss, FIT, S and J Peck (8, PECK); Kenai Pen, E Skilak Rd Jct Rt 1, 25 Jun 1984, aspen­spruce forest, malaise FIT, S and J Peck (17, PECK); Nenana, 13 mi NE Rt 3, mi 318, 27 Jul 1984, birch­spruce forest, malaise FIT, S and J Peck (9, PECK); 15 mi N Fox 30 mi N Fairbanks, 30 Jul 1984, mixed birch woods, malaise FIT, S and J Peck (14, PECK); 11 mi S Anderson Jct Rt 3 mi 270, 23 Jun 1984, alder, poplar, spruce, FIT, S and J Peck (40, PECK); Chena Ridge Rd, 5 mi W Fairbanks, 22 Jun 1984, poplar forest, malaise FIT, S and J Peck (33, PECK); Houston, 24 Jun 1984, spruce­birch forest with moss, malaise FIT, S and J Peck (33, PECK); Kenai Pen, Tern Lake, Jct, rts 1 & 9, 25 Jun 1984, poplar, spruce, alder, malaise FIT, S and J Peck (23, PECK); Tok, 21 Jun 1984, spruce­poplar, FIT, S and J Peck (9, PECK); Chena River Rec. Area 30 mi E Fairbanks, 22 Jun 1984, spruce forest, malaise FIT, S and J Peck (5, PECK); 11 mi S Anderson Jct Rt 3 mi 270, 23 Jun 1984, alder, poplar, spruce, malaise FIT, S and J Peck (2, PECK); Big Delta, 21 Jun 1984, spruce­willow, malaise FIT, S and J Peck (43, PECK); Seward, Salmon Creek, 26 Jun 1984, mature poplar­spruce, malaise FIT, S and J Peck (12, PECK); Kenai Pen. Tern Lake Jct Rts 1 & 9, 25 Jun 1984, poplar­spruce­alder, malaise FIT, S and J Peck (4, PECK); Chena Ridge Rd, 5 mi W Fairbans, 27 Jul 1984, birch­spruce forest, FIT, S and J Peck (17, CNCI); Seward, Salmon Creek, 26 Jun 1984, mature poplar­spruce forest, malaise FIT, S and J Peck (9, CNCI); Alaska Hwy 12 mi N Tok, 14 Jul 1985, carrion trap, SA Marshall (1, PECK); Ellito Hwy mi 27.8 White Mtn Trail, 16 Jul 1985, mushroom trap, SA Marshall (1, PECK); 15 mi N Fox 30 mi N Fairbanks, 30 Jul 1984, mixed birch woods, malaise FIT, S and J Peck (1, CNCI); Chena Ridge Rd, 5 mi W Fairbanks, 27 Jul 1984, birch­spruce forest, malaise FIT, S and J Peck (1, CNCI); Bonanza Creek Extension Forest nr Fairbanks, 12 Jul 1989, on Stemonitis sp. , SL Stephenson (6, CUIC); Chena River Rec. Area, 30 mi E Fairbanks, 22 Jun 1984, spruce forest, malaise FIT, S and J Peck (16, PECK); Chena Hot Springs, mi 50 Hot Springs Road, 28 Jul 1984, open spruce­moss taiga, malaise FIT, S and J Peck (1, PECK); campus woods, Univ. Alaska, Fairbanks, 30 Jul 1989, on Fuligo septica, SL Stephenson (19, CUIC). Arizona: (1, MCZC). Arkansas: Montgomery Co.: Crystal Rec. Area S campground, 27 Sep 1991, deciduous forest, C Carlton (1, LSAM); Polk Co.: Caney Creek Wild. Area 3.5 mi N Bard Springs, 20 Jan 1992, beech­maple, Berlese, C Carlton (1, LSAM); Caney Creek WA Sugar Creek, 4 Oct 1993, C Carlton (1, LSAM); Scott Co.: Hogan Mt. Turkey Area, 19 Oct 1991, deciduous forest, C Carlton (2, LSAM). California: Mohawk, Jun 1925, Fenyes (1, MCZC); Sugar Pine, Fenyes (1, CASC); Sta Cruz Mts (5, CASC); colr. (7, MCZC); Mohawk, Jun (1, CASC); Mohawk (3, CASC); Tuolumne Meadows, 7 Jul 1916 (1, MCZC); Amador Co.: 1 mi W Pine Grove, 24 Jun 1975, leaf litter, mixed conifer hardwood forest, A Newton, M Thayer (1, MCZC); Butte Co.: Garland Rd, 2 mi E Hwy 32, 27 Feb 1986, on Polyporus sp. on Quercus kelloggii, F Andrews, A Hardy, T Eichlin, D Mayhew (1, FGAC); 5 mi NE Butte Mdws, Cherry Hill Cpgd, 7 May 1976, FG Andrews (2, FGAC); Fresno Co.: Shaver Lake Heights, 26 Oct 1972, under bark, pine stump, AJ Gilbert (2, FGAC); Nevada Co.: 14.2 mi SW Alleghany, 4 Apr 1985, under Pinus bark, Andrews, Hardy (1, FGAC); Placer Co.: Carnelian Bay, Lake Tahoe, 24 Jun 1964, DF Veirs (1, MCZC); Plumas Co.: 14 Jun 1913 (1, MCZC); Butte Valley Dam, 30 Jun 1975, 4000̍, under bark conifer, A Newton, M Thayer (2, MCZC); Sierra Co.: Yuba Pass, 20 Jul 1983, 6700̍, F Andrews, A Hardy (2, FGAC); Tehama Co.: 10 mi SE Mineral, 4 Sep 1961, JF Lawrence (1, MCZC); Trinity Co.: 5 mi SE Peanut, 21 May 1973, under bark, Pinus ponderosa, J Doyen (2, EMEC); Tulare Co.: Sequoia Natl Park, Halstead Creek, 23 May 1984, 7000̍, R Baranowski (1, LUND). Colorado: Silverton, Jul 1934, Carpenter (1, MCZC); Grand Co.: 21 Aug 1983, 9600̍, on cream­colored plasmodium, SL Stephenson (2, CUIC); Gunnison Co.: 17 Aug 1983, 10,700̍, on orangeyellow plasmodium, SL Stephenson (13, CUIC); 17 Aug 1983, 10,700̍, on Fuligo septica, SL Stephenson (33, CUIC). Indiana: Indianapolis, 14 Jul 1910 (1, MCZC). Montana: Flathead Co.: Swan Lake, 2 Jul 1989, on Stemonitis axifera, SL Stephenson (1, CUIC); 27 Jun 1985, 6700̍, on Comatricha sp. , SL Stephenson (2, CUIC); Lake Co.: 29 Jun 1985, on Stemonitis sp. , SL Stephenson (10, CUIC). New Hampshire: Subalpine, Mt Washington, 4 Jul 1896 (3, MCZC); N Conway, Jun (1, MCZC); Mt Washington, 8 Sep 1926, Darlington (1, MCZC); Randolph, Sep 1904, JDS (1, MCZC); Mt Chocoura, 24 Jun 1932 (1, MCZC); Carr. Co.: The Bowl, 2.5 mi NW Wonalancet, 18 Sep 1985, FIT, DS Chandler (6, CNCI); 1 mi N Wonalancet E Park Spring Br, 18 Sep 1985, FIT, DS Chandler (2, CNCI); Coos Co.: Norton Pool, 3 mi NE East Inlet Dam, 22 Aug 1986, FIT, DS Chandler (13, CNCI); Straf Co.: Hubbard Brook Exp For., Bear Brook, 6 Jul 1983, rotten wood, DS Chandler (1, DENH). New York: Tompkins Co.: Ithaca, 17 Oct 1976, on Myxomycetes, T Hlavac (1, MCZC). Oregon: 5 mi NE Newberg, 14 Nov 1968, light trap, Anderson and Goeden (1, RLWE); Grants Pass, 2 Oct 1965, K Goeden (2, RLWE); Benton Co.: Mary’s Peak, 17 May 1983, 3500̍, Ribes litter, DS Chandler (1, DENH); Mary’s Peak, 20 Jun 1970, on polyporous fungus, RL Westcott (1, RLWE); Clackamas Co.: 10 mi N 10 mi E Gout Camp, Mt Hood rd 5–31, 30 Aug 1972, 5500̍, hemlock litter, Benedict (6, PECK); Clackamas Co.: 1.5 mi S jct US 26 Ore. 35, 11 Jul 1975, litter, mixed conifer forest, Berlese, A Newton, M Thayer (1, MCZC). Utah: Garfield Co.: Aquarius Plateau, Bluebell Knoll, Mar 1986 – Sep 1986, pitfall trap, AJ Gilbert (23, FGAC); Wasatch Co.: Lost Lake Camp, Uinta Mountains, 29 Aug 1940, 7800̍, HP Chandler (1, CASC). Washington: Pierce Co.: Mt Rainier Natl Park 4.7 mi W Longmire, 26 Jul 1975, 2200̍, on Fuligo septica, A Newton, M Thayer (2, MCZC); Yakima Co.: 8 mi SW Tieton RS, Snoqualmie NF Bear Creek, 11 Jun 1973, WJ Turner (17, WSUC).

DISCUSSION: This species has been described several times based on supposed degree of angulation of the lateral corners of the pronotum, type of dorsal punctation, and presence or absence of a male mandibular horn. We are unable to find any significant differences in degree of angulation between any of the many specimens examined, including the type specimens of A. angulare , A. municeps , and A. assimile . There are some differences in the type of punctation, however. Dorsal punctation of the elytra and, to a lesser extent, the pronotum and head vary from relatively coarse and sparse to very fine and dense. Specimens from the eastern portion of the range (such as from where A. municeps was described) are often much more finely and densely punctate. However, male genitalia and other characters such as the nature of the metasternum and male metasternal fovea agree in all the populations studied throughout the range of the species, and punctation tends to be quite variable within as well as among populations, suggesting that this character is not useful for delimiting species. Therefore, we have synonymized A. angulare , A. municeps , and A. assimile . A. angulare has priority. Interestingly, although Hatch advised Fall that A. temporale was preoccupied ( Fall, 1934a), and Hatch knew of Fall’s (1934a) replacement of A. temporale Fall with A. municeps ( Hatch, 1936) , he still erected a new replacement name, A. falli ( Hatch, 1957) , although by this time it was unnecessary.

This species has been collected during every month. The species occurs in a broad variety of forest types and has been collected in a number of trap types including flight intercepts, pitfalls, and ‘‘carrion traps’’. Elevation records are from 2200 ft (Washington) to 10,700 ft (Colorado). Host records from specimen labels include: Brefeldia maxima , Comatricha sp. , Fuligo septica , Stemonitis axifera , Stemonitis sp. , Polyporus sp. , and from ‘‘cream­colored’’ and ‘‘orange­yellow’’ plasmodia.

Figures

Fig. 1. Agathidium angulare, dorsal habitus.

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.

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. 42. Geographic distribution of Agathidium angulare.