Pinodytes borealis Peck & Cook, 2011

Peck, Stewart B. & Cook, Joyce, 2011, Systematics, distributions and bionomics of the Catopocerini (eyeless soil fungivore beetles) of North America (Coleoptera: Leiodidae: Catopocerinae) 3077, Zootaxa 3077 (1), pp. 1-118 : 18-19

Pinodytes borealis Peck & Cook , new species

( Figs. 3 , 52–61 )

Type material. Holotype: male ( SBPC). UNITED STATES. Alaska: Chena Ridge, 5miW Fairbanks, 27.VII.84, S. & J. Peck, alder litter . Paratypes (145). UNITED STATES. Alaska: same data as holotype, 69 ( SBPC) , 17 ( FMNH); Chena Hot Spgs., mi 49 Chena River Rd. , 28.VII.84, 1000’, S. & J. Peck, birch-alder litter, S face slope, 24 ( SBPC) ; Circle Hot Springs , 6.VIII.84, S. & J. Peck, alder-poplar-willow forest litter, 29 ( SBPC) ; Lost Creek, 7miN Livengood , 30.VII.84, S. & J. Peck, carrion, 5 ( SBPC) .

Material examined. We have examined 145 specimens.

Distribution. Specimens ( Fig. 52 ) are known from the vicinity of Fairbanks, in formerly unglaciated central Alaska. We interpret these populations to be relictual and indicating a Tertiary distribution, before Pleistocene glaciations caused the extinction of other populations and species in western North America.

Diagnostic description. Total length 2.02–2.10 mm; greatest width 0.92–0.96 mm. Reddish brown; elongateoval in shape ( Fig. 3 ). Head. Finely, sparsely punctate, shining, with faint reticulate microsculpture on vertex and sides. Eyes absent. Antennae ( Fig. 53 ) with antennomeres 2 and 3 subequal in length; antennomere 5 longer than 4 and 6; antennomere 7 clearly larger than 8; antennomeres 9 and 10 lack visible sensory vesicles. Pronotum. Finely, sparsely punctate, shining, with faint reticulate microsculpture. Slightly wider at middle than at base, narrowing from middle to apex; apical margin weakly emarginate, basal margin straight; apical angles rounded, basal angles nearly right-angled. Elytra. Strial punctures in rows, weakly impressed medially in basal one-half; interstrial punctures variable in size and density; shining. Joined elytra widest near middle, wider than pronotum, sides moderately rounded, rounded at apex. Legs. Protibia ( Fig. 54 ) moderately slender; outer margin with spine one-fifth from apex; apex spinose; inner margin with fine spines on apical two-thirds. Mesotibia ( Fig. 55 ) moderately slender; apical one-half of inner margin finely spinose, outer margin and apex spinose. Metatibia ( Fig. 56 ) elongate, narrow, straight; fine spines on apical one-half of inner margin; spinose at apex. Metafemur ( Fig. 56 ) slender. Male protarsomeres ( Fig. 54 ) and mesotarsomeres ( Fig. 55 ) little expanded, bearing elongate setae laterally and thin, broad, colorless phanerae ventrally in two rows. Venter. Mesoventrite ( Fig. 61 ) carinate; longitudinal carina expanded at middle, not excavated behind transverse carina. Male genitalia. Median lobe of aedeagus ( Figs. 57, 59 ) elongate, broad, with apex flattened and dorsoventrally sinuate. Everted internal sac ( Fig. 58 ) with a bifurcated sclerotized structure, a single elongate spine, and numerous small spines. Parameres ( Figs. 57, 59 ) straight, not reaching apex of median lobe, each with two apical setae. Spermatheca. Elongate ( Fig. 60 ), tubular, curved.

Etymology. The name borealis, Latin , northern, refers to the northern distribution of this species.

Bionomics. The collections are all from leaf litter of broadleaf forests (aspens) on loess soils. These soils are deep, well drained, and warmer than other soil types in central Alaska. We suggest that these soil properties are important for the northern survival of the species. These soils are the same as those in which is found the eyeless northern relictual soil staphylinid Chionotyphlus alaskensis Smetana (1986) .

Figures

FIGURE 52. Distributions of basal and monobasic species groups of Pinodytes in western United States. P. newtoni, closed circles in Missouri, Arkansas, and Texas. P. borealis, closed circles in inset map of Alaska. P. punctatus, open squares in eastern Washington and northern Idaho. P.colorado, open circles in western Colorado. Note: in this and all following maps, small open circles represent major cities.

FIGURES 53–61. Pinodytes borealis. 53. Male right antenna, dorsal. 54. Male right protibia and protarsus. 55. Male right mesotibia and mesotarsus. 56. Male right metafemur and metatibia. 57. Aedeagus, lateral. 58. Everted internal sac, lateral. 59. Aedeagus, dorsal. 60. Spermatheca. 61. Mesoventrite, lateral. Scale bar = 0.1 mm (Fig. 60), 0.25 mm (Fig. 61), 0.3 mm (Figs. 57–59), 0.4 mm (Figs. 53–55), 0.5 mm (Fig. 56).

FIGURES 2–10. Pinodytes habitus photos. 2. P.newtoni, total length 1.38 mm. 3. P. borealis, total length 2.10 mm. 4. P. punctatus, total length 1.36 mm. 5. P.colorado, total length 1.66 mm. 6. P.pusio, total length 1.54 mm. 7. P. ovatus, total length 1.34 mm. 8. P. chandleri, total length 1.54 mm. 9. P. constrictus, total length 1.48 mm. 10. P.contortus, total length 1.16 mm.