Phalacropsis Casey, 1890

Gimmel, Matthew L., 2013, <strong> Genus-level revision of the family Phalacridae (Coleoptera: Cucujoidea) </ strong>, Zootaxa 3605 (1), pp. 1-147 : 51-53

11. Phalacropsis Casey, 1890

( Figs. 3d ; 14 ; 39c )

Phalacropsis Casey 1890: 101 . Type species: Phalacrus dispar LeConte 1879 , fixed by monotypy.

Type material. Phalacrus dispar LeConte : holotype, “Veta Pass \ 21.6 [number handwritten] \ Col // 344 [handwritten] // P. dispar \ Lec. [handwritten] // Type \ 6644 [red label, number handwritten] // HOLOTYPE \ Phalacrus \ dispar LeConte \ det. M.L. Gimmel 2010 [red label]” ( MCZ), point mounted.

Diagnosis. Recognized by the lack of a protibial ctenidium, large scutellar shield, lack of a sutural stria, protruded metaventral process, metatarsomere I shorter than II, and female ovipositor with gonocoxae not spiniform.

Description. Small to large, total length 1.7–3.2 mm. Dorsal color testaceous to brunneous ( Fig. 39c ). Tibial spur formula 2-2-2, tarsal formula 5-5- 5 in both sexes.

Head. Not constricted behind eyes. Eyes small; facets flat; interfacetal setae absent; weakly emarginate medially; without posterior emargination; periocular groove absent; with transverse setose groove ventrally behind eye. Frontoclypeus not or barely emarginate above antennal insertion; clypeal apex arcuate-truncate. Antennal club 3-segmented, club weakly asymmetrical; antennomere XI not constricted, often elongate ( Fig. 14b ). Mandible ( Fig. 14a ) with apex tridentate; retinaculum present, strong; mandible without ventral ridge. Maxillary palpomere IV cylindrical, elongate, narrower than palpomere III, nearly symmetrical; galea short, rounded; lacinia with two stout spines. Mentum with sides divergent toward apex; labial palpomere III fusiform. Labrum with apical margin truncate. Gular sutures short, barely evident.

Thorax. Pronotum without obvious microsetae; with scutellar lobe weakly developed. Prosternum anteriorly with continuous row of marginal setae, setae normal; procoxal cavity with anterolateral notchlike extension; prosternal process rounded in lateral view, not conspicuously setose preapically, without row of spinelike setae at apex. Protrochanter with setae; protibia without ctenidium on kickface ( Fig. 14c ). Scutellar shield large, width at base greater than length of eye. Elytron without spectral iridescence; without sutural stria; disc without even rudimentary striae or rows of punctures; without transverse strigae; lateral margin with row of tiny, sawtooth-like setae. Mesoventral plate ( Fig. 14f ) notched anteriorly, not extending posteriorly to metaventrite, forming procoxal rests; mesoventrite sunken medially, with scattered setae; mesanepisternum with complete transverse carina; mesocoxal cavities separated by much greater than half width of a coxal cavity. Mesotarsomere III bilobed. Metaventral process ( Fig. 14f ) extending beyond anterior level of mesocoxae, highly protruding and lobed anteriorly; metaventral postcoxal lines not separated from mesocoxal cavity margin; discrimen short, extending less than halfway to anterior margin of metaventral process; metendosternite ( Fig. 14g ) with anterior tendons widely separated, ventral process intersecting ventral longitudinal flange behind anterior margin. Anterior margin of metacoxa with emargination sublaterally; metacoxal plate with transverse line; metafemur with subapical row of long setae on posteroventral surface; metatibial foreface with apical ctenidium roughly perpendicular overall to long axis of tibia; spurs cylindrical, longest spur much shorter than width of tibial apex; metatarsomere I shorter than metatarsomere II, joint between I and II flexible, tarsomeres with hairy pads similar to those of pro- and mesotarsus ( Fig. 14d ). Hind wing ( Fig. 14e ) with distinct, ovate anal lobe; leading edge without row of long setae at level of RA +ScP; AA 3+4 not apparent; cubitoanal system unbranched apically; CuA 2 and MP 3+4 without distal remnants; r4 absent; flecks absent from apical field distal to rp-mp2; extremely small flecks present in region just distal to end of radial bar.

Abdomen. Abdominal ventrite I without paired lines or calli; spiracles apparently absent from segment VII. Male with aedeagus rotated in repose, resting on its side; tegmen ( Fig. 14h ) with symmetrical anterior margin, with pair of acute struts, parameres fused to basal piece, parameres divided longitudinally; penis ( Fig. 14i ) with unpaired endophallic sclerites, apex simple; spiculum gastrale V-shaped, arms free. Female ovipositor ( Fig. 3d ) moderately sclerotized; gonocoxites not modified into spinose structures; gonostyli attached apically.

Immature stages. Larvae have not been formally described for this genus, although the mandible was illustrated in Steiner (1984: 441). The mandible possesses what appears to be a true mola, which is reflective of spore-mass-feeding habits.

Bionomics. The larvae of Phalacropsis dispar appear to be highly host specific, feeding on aeciospores and underlying sporogenous mycelium of native western pine stem rust fungi ( Peridermium spp. ) on various species of pines ( Pinus spp. ). The life cycle is completed in about 30 to 40 days, during which the larvae generally completely consume the contents of the aecia they infest, and appear to be highly effective in natural control of the rust fungus ( Nelson 1982; Steiner 1984).

Distribution and diversity. The exact limits of this genus are unknown, and will require dissection of female genitalia to resolve. Occurring from Oregon and Idaho south to at least Venezuela and Bolivia. Apparently restricted to highland regions.

Included species (3):

Phalacropsis dispar (LeConte, 1879) (Distribution: United States) (type!)

Phalacropsis lucidus ( Sharp, 1888) , comb. nov. ( Phalacrus ) ( Distribution : Guatemala) (type!)

Phalacropsis scutellaris ( Sharp, 1888) , comb. nov. ( Phalacrus ) ( Distribution : Guatemala) (type!)

Discussion. Although Phalacropsis may render Phalacrus paraphyletic I am presently acknowledging their distinctness by maintaining them as separate genera. This includes the transfer of two Sharp species described from Guatemala in the genus Phalacrus to Phalacropsis . These new combinations are made explicit above.

Figures

FIGURE 3. Key characters for Phalacridae. (a) Prosternal process of Acylomus aciculatus Sharp (scale bar = 0.5 mm). (b) First abdominal ventrite of Malagophytus steineri Gimmel. Ovipositor of (c) Phalacrus sp.; (d) Phalacropsis dispar (LeConte); (e) Olibrus aeneus (Fabricius); (f) Litostilbus testaceus (Fabricius) (scale bars = 0.5 mm).

FIGURE 14. Phalacropsis dispar, female. (a) Left mandible, dorsal; (b) left antenna (scale bar = 0.5 mm). (c) Left protibia and tarsus, dorsal; (d) left metatibia and tarsus, ventral (scale bar = 0.5 mm). (e) Hind wing (scale bar = 1.0 mm). (f) Meso- and metaventrite, ventral (scale bar = 1.0 mm). (g) Metendosternite (scale bar = 0.5 mm). Male. (h) Tegmen, ventral; (i) penis, ventral (scale bar = 0.5 mm).

FIGURE 39. Photographs. Megistopalpus simoni, lectotype: (a) dorsal; (b) view of antenna and maxillary palp. Phalacropsis dispar: (c) dorsal. Phalacrus rufoguttatus: (d) dorsal; (e) ventral. Austroporus sp.: (f) dorsal. Platyphalacrus lawrencei: (g) dorsal; (h) lateral; (f) ventral.