Agathidium amae 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 : 45-48

Agathidium amae Miller and Wheeler ,

new species Figures 50 , 58, 59 , 90

TYPE MATERIAL: Holotype, Ƌ in CASC labeled ‘‘ CALIF: Placer Co. Kings Beach along Griff Creek V­26­85 6600̍ Fred G. Andrews/collected under bark Pseudotsuga menziesii / HOLOTYPE Agathidium amae Miller and Wheeler, 2003 [red label with black line border]’’.

TYPE LOCALITY: United States, California, Placer Co., Kings Beach along Griff Creek, 6600̍.

DIAGNOSIS: This species is very similar to A. pulchrum and A. maculosum in general shape, presence of prominent dorsal maculation (fig. 50), and similar male genitalia. In these three species there is a small cavity medially on the ventral margin of the median lobe of the aedeagus (figs. 55, 57, 59). Agathidium amae differs from A. maculosum in possessing a prominent sutural stria (fig. 50). Also, the operculum of the median lobe of the aedeagus is hyaline and indistinct in A. amae (fig. 58), whereas in A. maculosum it is very prominent (fig. 54). From A. pulchrum this species differs in generally being more lightly maculate (with more extensive yellow coloration dorsally) (fig. 50), and the apical portion of the median lobe of the aedeagus is much more evenly narrowed in ventral aspect (fig. 58).

DESCRIPTION: Body moderately large (TBL = 2.38–2.57 mm), rotund (PNW/TBL = 0.46–0.49), laterally broadly rounded, moderately strongly contractile.

Head yellow­brown; pronotum yellow­orange; elytra yellow­orange with diffuse brown triangle basally and with brown along anterior and lateral margins, often with elongate oval brown macula medially, which is confluent with anteromedial brown triangle in some specimens (fig. 50); venter yellow except metasternum, which is dark redbrown to piceous; antennae yellow, basal two club antennomeres brown, apical antennomere yellow; palpi yellow; legs yellow­brown to yellow.

Head broad (fig. 50) (MDL/OHW = 0.51– 0.63), dorsally flattened, without medial crease; temporum short, inconspicuous, forming a distinct rim at posterior margin of eye; head finely and sparsely punctate, surfaces shiny and smooth between punctures; eyes large, rounded, finely faceted; frontoclypeal suture moderately prominent medially; clypeal margin strongly excavate (fig. 50); labrum broadly emarginate along anterior margin; antennomere ratios: length I:II:III = 2.1:1.0:1.9, width VII:VIII:IX = 1.0:1.0:1.8. Pronotum broad (PNL/PNW = 0.57–0.58), laterally not strongly produced, anterolateral angle subquadrate, posterolateral angle distinctive, more rounded than anterolateral angle; punctation similar to that of head. Elytra moderately robust (SEL/ELW = 1.01–1.05); lateral margins rounded; punctation moderately coarse but sparse, some in indistinct series, surface between punctures shiny and smooth; sutural stria prominent, extending about one­half length of elytron. Mesosternum strongly 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 moderately broad medially (MTL/ MTW = 0.29–0.32), slightly convex, setose; oblique carinae absent.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres slightly expanded and with moderately large ventral field of spatulate setae; mandibular horn, when fully developed, very long, extending posteriorly over front of head in long, curved, rounded horn, apex rounded, setose along its length, with prominent subapical fovea and marginal series of fine setae; metafemur slender, unmodified; metasternal fovea round, located slightly anterior of middle, with cluster of fine setae. Median lobe in lateral aspect with prominent basal portion and submedial constriction, straight dorsad of constriction, apical portion slightly curved, robust, apically rounded (fig. 59); in ventral aspect slender, parallel­sided, apical portion moderately slender, evenly tapered to rounded apex (fig. 58); operculum inconspicuous, narrow, hyaline, apically narrowly rounded (fig. 58); lateral lobes slender, curved basally, apically pointed with 2 long, stout setae (figs. 58, 59).

Female tarsi 5­4­4.

ETYMOLOGY: This species is named in hon­ or of the wife of the senior author, Amy Beth Miller, for her considerable contribution to his life and support of his research efforts.

DISTRIBUTION: This species is known only from California and Washington (fig. 90).

PARATYPES: Sixteen paratypes were examined from the following localities: UNITED STATES. California: Butte Co.: 5 mi NE Butte Meadows, Cherry Hill Cpgd , 24 May 1974, FG Andrews (4, FGAC) ; El Dorado Co.: 1 mi W Grizzly Flat , 24 Mar 1982, under oak bark, F Andrews (1, FGAC) ; Blodett Exp. For. 14 mi E Georgetown, 8 May 1976, J Doyen (1, EMEC) ; Yuba Co.: 1 mi W Strawberry Vy. Rang. Sta. , 6 May 1980, 3600̍, on slime mold on Pseudotsuga, JT Doyen (9, EMEC) ; Washington; Olympic NP, 20 Jun 1984, R Danielsson (1, LUND) .

Agathidium laetum Fall

Figures 6 , 60, 61 , 89

Agathidium laetum Fall, 1934b: 118 .

TYPE MATERIAL: Lectotype (designated here to clarify assignment of this name with this species), ♀ in MCZC labeled ‘‘Pasadena Cal./ TYPE laetum [‘‘TYPE’’ underlined in red, ‘‘laetum’’ handwritten]/M.C.Z. Type 24039 [red label, number handwritten]/H. C. FALL COLLECTION / LECTOTYPE Agathidium laetum Fall , des. Miller and Wheeler, 2002 [red label with black line border]’’. Fall ordinarily designated holotypes, but in the case of this species he did not, possibly because he had two females and no male.

TYPE LOCALITY: United States, California, Pasadena.

DIAGNOSIS: This species can be differentiated from other members of the group by the concolorous elytra, the anterior clypeal margin broadly convex and extending distinctly beyond the anterolateral margins of the frons (fig. 6), the mesosternum with a prominent, flattened lobe extending ventrally between the mesocoxae, the male left mandible without a horn, the median lobe in ventral aspect broadly expanded apically (fig. 60), and the operculum with a prominent, deep, narrow medial emargination (fig. 60). Females have 4­4­4 tarsi.

DESCRIPTION: Body small (TBL = 2.46– 2.47 mm), robust (PNW/TBL = 0.41–0.43), laterally broadly rounded, weakly contractile.

Head and elytra red; pronotum red with yellow around margins; venter yellowbrown; antennae, palpi and legs red­yellow.

Head relatively elongate (fig. 6) (MDL/ OHW = 0.74–0.78), dorsally flattened, without medial crease; temporum very short, inconspicuous; head finely and sparsely punctate, coarser anteromedially, surfaces shiny and smooth between punctures; eyes large, rounded, finely faceted; frontoclypeal suture indistinct medially; clypeal margin curved, extending slightly but distinctly beyond anterolateral margins of frons (fig. 6); labrum entire; antennomere ratios: length I:II:III = 2.1:1.0:1.2, width VII:VIII:IX = 1.0:1.0:1.8. Pronotum broad (PNL/PNW = 0.59–0.61), lateral margin relatively broad, laterally not strongly produced, anterolateral angle subquadrate, posterolateral angle distinctive, somewhat rounded; punctation similar to that of head, fine and sparse. Elytra broad and robust (SEL/ELW = 1.13–1.16); lateral margins rounded; punctation coarse, moderately dense, some arranged in indistinct, irregular series, surface between punctures shiny and smooth; sutural stria absent. Mesosternum strongly concave posteriorly, with prominent lobe extending ventrally between mesocoxae, anterior portion extremely short; medial longitudinal carina absent on anterior portion. Metasternum broad medially (MTL/MTW = 0.35–0.42), slightly convex, nearly glabrous; oblique carinae absent.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres slightly expanded and with small ventral field of spatulate setae; left mandible not modified; metafemur slender, unmodified; metasternal fovea double, comprised of a large, round brush of fine setae on each side of midline slightly anterad of middle. Median lobe in lateral aspect with large robust basal portion and constriction, area distad of constriction slender, curved, apical portion slender, directed slightly dorsad, apically slightly expanded and truncate (fig. 61); in ventral aspect slender basally, evenly expanded to apical portion, which is broad, apically abruptly narrowed to broadly rounded apex (fig. 60); operculum broad, flat, apically broadly rounded with deep, narrow, medial emargination (fig. 60); lateral lobes long, slender, apically narrowly rounded, with 2 long, stout setae (figs. 60, 61).

Female tarsi 4­4­4.

DISTRIBUTION: This species is known from southern California (fig. 89).

SPECIMENS EXAMINED: UNITED STATES. California: Sierra Madre (1, CASC) ; Pasadena (1, MCZC) ; Pasadena, Feb (7, CASC) ; Pasadena, 15 Apr 1905, paralectotype (1, MCZC) ; San Diego, FE Blaisdell (2, CASC) .

DISCUSSION: This small species has been relatively rarely collected, despite its occurrence in California, a relatively heavily collected area. The only habitat record is from leaf litter in a mixed hardwood and conifer forest.

Agathidium athabascanum Fall Figures 7 , 62, 63 , 89

Agathidium athabascanum Fall, 1934b:119 .

Agathidium alticola Fall, 1934b:120 . NEW SYNO­

NYM.

TYPE MATERIAL: Agathidium athabascanum : holotype, Ƌ in MCZC labeled ‘‘Jasper Park Alb. VIII 4 ’24/Ƌ/ TYPE athabasca­num

[name handwritten, red line under ‘‘TYPE’’]/ M.C.Z. Type 24028/H.C. FALL COLLEC­ TION / Agathidium athabascanum Fall [handwritten, red line around border]’’.

Agathidium alticola : holotype, Ƌ in MCZC labeled ‘‘Wt Mts N.H. Subalp/Ƌ/ TYPE alticola [name handwritten, red line under ‘‘TYPE’’]/M.C.Z. Type 19572 [number handwritten, red label]/H.C. FALL COL­ LECTION.’’

TYPE LOCALITY: Agathidium athabascanum : Canada, Alberta, Jasper Park.

Agathidium alticola : United States, New Hampshire, White Mountains.

DIAGNOSIS: This species differs from other members of this group by the concolorous, light brown dorsal surfaces, the anterior clypeal margin convex and extending distinctly, but not greatly, beyond the anterolateral margins of the frons (fig. 7), the mesosternum without a ventrally extending, flattened lobe between the mesocoxae, males without a left mandibular horn, the median lobe of the aedeagus in lateral aspect with the apex very sharply pointed and strongly curved dorsad (fig. 63), and the operculum apically expand­ ed and medially distinctly emarginate (fig. 62). Females have 5­4­4 tarsi.

DESCRIPTION: Body moderately large (TBL = 2.18–2.67 mm), robust, broadly rounded (PNW/TBL = 0.49–0.57), moderately contractile.

Head, pronotum, and elytra yellow­brown to yellow­red; venter yellow to yellowbrown; antennae and palpi yellow; legs yellow to yellow brown.

Head broad (fig. 7) (MDL/OHW = 0.58), somewhat convex, without transverse, medial crease; temporum short, often forming distinct rim at posterior margin of eye (fig. 7); head moderately coarsely punctate, with two puncture sizes, large and fine micropunctules interspersed, some specimens nearly impunctate; eyes large, rounded, finely faceted; frontoclypeal suture moderately well defined medially; clypeal margin curved, extending distinctly beyond anterolateral margins of frons (fig. 7); anterior margin of labrum entire; antennomere ratios: length I:II: III = 1.6:1.0:1.4, width VII:VIII:IX = 1.0: 1.0:1.6. Pronotum broad (PNL/PNW = 0.51–0.54), laterally not strongly produced, anterior margin not strongly concave, antero­ lateral angle subquadrate, posterolateral angle distinctive, but rounded; punctation and surface microsculpture similar to that of head, some specimens nearly impunctate. Elytra robust, broad (SEL/ELW = 0.83–0.99); coarsely punctate, more dense apically, not in series, with fine irregular microreticulation on surfaces between punctures; sutural stria about one­half length of elytron on most specimens. Mesosternum strongly concave posteriorly, without prominent lobe extending ventrally between mesocoxae, anterior portion less about one­half length of posterior portion; medial longitudinal carina absent on anterior portion. Metasternum relatively broad medially (MTL/MTW = 0.36), slightly convex, setose; oblique carinae absent.

Male tarsi 5­5­4; pro­ and mesobasotarsomeres slightly expanded and with small ventral field of spatulate setae; left mandible unmodified in all specimens examined; metafemur very slender, otherwise unmodified; metasternal fovea small, slightly anterad of middle, slightly transverse with small brush of fine, dense setae. Median lobe in lateral aspect robust, with large basal region and sub­basal constriction, broad and slightly curved distad of constriction, apical portion long, slender and strongly and evenly curved dorsad (fig. 63); in ventral aspect broad, lateral margins subparallel, apical portion broad, broadly acuminate to sharp apex, orifice large (fig. 62); operculum fused to proximal margin of orifice, long, flat, slightly expanded, apex broad and medially emarginate (fig. 62); lateral lobes long, slender, curved basally, apex narrowly rounded with 2 long setae (figs. 62, 63).

Female tarsi 5­4­4.

DISTRIBUTION: This far northern species is known from Alaska and the Yukon south through British Columbia and Alberta east to high elevation areas of New Hampshire (fig. 89).

SPECIMENS EXAMINED: CANADA: Alberta: Jumpinground Creek , 20 Oct 1962, forest litter, BF and JL Carr (4, CARR) ; Elke Island NP White Spruce Trail , 9 May 1984, moose dung and Sphagnum, RS Anderson (2, CNCI) ; Waiparous , 4 Sep 1960, on ‘‘toadstools’’, BF and JL Carr (3, CARR) ; 3.8 m N Cadomin , 4 Aug 1985, lodgepole pine forest, FIT, RS Anderson (1, CNCI) ; Demmitt, 3 km W 90 km NW Grand Prairie, 12 Jun 1984, poplar forest, FIT, S and J Peck (1, CNCI). British Columbia: Mt Robson P Park , Berg Lake Trailhead , 11 Jul 1984, FIT, RS Anderson (2, PECK) ; Barkeyville, 15 Jul 1969, on forest floor, BF and JL Carr (1, CARR). Manitoba: Devils Lake 100 km S Grand Rapids, 7 Jun 1984, pine­aspen forest, FIT, S and J Peck (1, CNCI) ; Churchill, 3 Aug 1950, WJ Brown (1, CNCI). Yukon: Whitehorse , 4 Sep 1936, SM Williams (1, MCZC) ; Dempster Hwy km 141 Blackstone River , 6 Jul 1985, dung traps, SA Marshall (21, PECK) ; Carmacks , 2 Sep 1936, SM Williams (2, MCZC) ; km 147 Dempster Hwy, Fen Willows­spruce , 1 Jul 1985, dung pan trap, SA Marshall (3, PECK) .

UNITED STATES: Alaska: Tolovana Rd + Elliot Hwy mi 57, 18 Jul 1985, mushroom trap, SA Marshall (1, PECK) ; Delta River mi 227 Rich. Hwy. , 5 Jul 1958, Lindroth (1, MCZC) ; Kenai Pen. E Skilak Rd Jct Rt 1, 25 Jun 1984, aspenspruce forest, malaise FIT, S and J Peck (1, PECK) ; Circle Hot Springs , 6 Aug 1984, alderpoplar­willow forest litter, S and J Peck (1, PECK) ; Kenai Pen. Summit Lake, Rt 1, 26 Jun 1984, treeline dwarf willow litter, Berlese, S and J Peck (2, PECK) ; Denali NP Reily Creek Camp, 10 Aug 1984, 1700̍, taiga forest, on ‘‘mushrooms’’, Berlese, S and J Peck (4, PECK) ; Chena Ridge 5 mi W Fairbanks, 27 Jul 1984, alder litter, Berlese, S and J Peck (2, PECK) ; Tenana, 21 Aug 1936, SM Williams (1, MCZC). New Hampshire: Mt Washington, 7 Jul 1899 (1, MCZC) ; White Mts , subalpine (8, MCZC) ; White Mts , 4 Jul 1896, subalpine (15, MCZC) ; Mossiland , 24 Aug 1896 (1, MCZC) .

DISCUSSION: The names synonymized here, A. athabascanum and A. alticola , were erect­ ed based in part on purported differences in the shape of the lateral margin of the pronotum. However, we find that the types of each of these fall well within the range of variation of a single species diagnosed from the shape of the median lobe of the aedeagus. Agathidium athabascanum comes first in Fall’s (1934b) treatment, so we selected it as the valid name.

This is one of the most northerly occurring species in North America. Specimens have been collected from typical northern habitats such as alder, aspen, conifer, and mixed forests, including areas near or north of the tree line. The only host records from label data are ‘‘toadstools’’ and ‘‘mushrooms’’.

Figures

Figs. 48–51. Agathidium pulchrum­group species, dorsal habitus: 48, A. difforme. 49, A. maculosum.

Figs. 52–69. Agathidium pulchrum­group species, aedeagus: 52, 53, A. difforme: 52, ventral; 53, lateral. 54, 55, A. maculosum: 54, ventral; 55, lateral. 56, 57, A. pulchrum: 56, ventral; 57, lateral. 58, 59, A. amae: 58, ventral; 59, lateral. 60, 61, A. laetum: 60, ventral; 61, lateral. 62, 63, A. athabascanum: 62, ventral; 63, lateral. 64, 65, A. columbianum: 64, ventral; 65, lateral. 66, 67, A. rusticum: 66, ventral; 67, lateral. 68, 69, A. repentinum: 68, ventral; 69, lateral.

Fig. 90. Geographic distribution of Agathidium pulchrum­group species: A. amae = -; A. repentinum = •.

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.

Fig. 89. Geographic distribution of Agathidium pulchrum­group species: A. athabascanum = -; columbianum = *; A. laetum = •; A. rusticum = ^.