Steinerlitrus Gimmel, 2013

Gimmel, Matthew L., 2013, <strong> Genus-level revision of the family Phalacridae (Coleoptera: Cucujoidea) </ strong>, Zootaxa 3605 (1), pp. 1-147 : 120-122

34. Steinerlitrus Gimmel , gen. nov.

( Figs. 36 ; 43c–e )

Type species: Steinerlitrus warreni Gimmel , here designated.

Type material. See account of Steinerlitrus warreni below.

Diagnosis. Readily distinguised from other Phalacridae by the greatly anteriorly protruded metaventrite, lack of a protibial ctenidium, metatarsomere II longer than I, small scutellar shield, acute notch on the posterior margin of the eye, and a reduced or absent elytral sutural stria.

Description. Very small to medium-sized, total length 1.2–2.4 mm. Color generally piceous, often with yellow maculations ( Figs. 43d, e ). 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; not emarginate medially; with acute posterior emargination ( Fig. 43c ); periocular groove absent; lacking distinct setose groove ventrally behind eye. Frontoclypeus emarginate above antennal insertion; clypeal apex arcuate-truncate. Antennal club 3- segmented, club strongly symmetrical, antennomere XI strongly turbinate ( Fig. 36b ). Mandible ( Fig. 36a ) with apex tridentate; without retinaculum; mandible with ventral ridge. Maxillary palpomere IV fusiform, nearly symmetrical; galea short, rounded; lacinia with two stout spines. Mentum with sides divergent toward apex; labial palpomere III fusiform, pointed apically. Labrum with apical margin arcuate, with tuft of inwardly curved setae at each corner. Gular sutures short, barely evident .

Thorax. Pronotum with scattered, distinct microsetae; with weakly developed scutellar lobe. Prosternum anteriorly with continuous row of marginal setae, setae flattened at base; procoxal cavity with anterolateral notchlike extension; prosternal process rounded in lateral view, often conspicuously setose preapically, without spinelike setae at apex. Protrochanter without setae; protibia without ctenidium ( Fig. 36c ). Scutellar shield small. Elytron without or with weak spectral iridescence; without or with one weak sutural stria; elytral disc with weak rows of punctures; without transverse strigae; lateral margin with row of tiny, sawtooth-like setae. Mesoventral plate ( Fig. 36f ) notched anteriorly, extending posteriorly to metaventrite, dividing mesoventral disc in two, not forming procoxal rests; mesanepisternum with complete transverse carina; mesocoxal cavities widely separate, separated by more than width of a coxal cavity. Mesotarsomere III not bilobed. Metaventral process ( Fig. 36f ) extending beyond anterior level of mesocoxae, protruding and arcuately lobed anteriorly; metaventral postcoxal lines not separated from mesocoxal cavity margin; discrimen extremely short, extending much less than halfway to anterior margin of metaventral process; metendosternite ( Fig. 36g ) with anterior tendons moderately separated, ventral process intersecting ventral longitudinal flange at anterior margin. Anterior margin of metacoxa with emargination sublaterally; metacoxal plate with transverse line; metatibial foreface with apical ctenidium roughly perpendicular overall to long axis of tibia; spurs cylindrical, quite short, distinctly shorter than width of tibial apex; metatarsomere I shorter than metatarsomere II, joint between I and II rigid ( Fig. 36d ). Hind wing ( Fig. 36e ) with distinct, ovate anal lobe; leading edge with complete row of long setae at level of RA +ScP; AA evident only basally, without crossvein to Cu; cubitoanal system unbranched apically; CuA 2 and MP 3+4 without distal remnants, though faint flecking is often present; r4 absent; with strong fleck in apical field just distal to rp-mp2; short transverse proximal sclerite and faint triangular sclerite present just distal to end of radial bar.

3+4

Abdomen. Abdominal ventrite I without paired lines, with calli; spiracles present and apparently functional on segment VII. Male with aedeagus upright in repose; tegmen ( Fig. 36h ) with asymmetrical anterior margin and parameres completely fused to basal piece or partially separated by suture, parameres with medial longitudinal division; penis ( Fig. 36i ) with endophallic spicules in cylindrical arrangement, apex truncate; spiculum gastrale Vshaped, distorted, arms free. Female ovipositor weakly sclerotized, palpiform.

Immature stages. Unknown.

Bionomics. Large series of both an undescribed species and S. warreni were collected from the trunk of a living Macrolobium sp. (Fabaceae) at night. One specimen of an undescribed species was sifted from a stataryphase colony of Eciton burchelli Westwood (Formicidae) , but the presence of the phalacrid was likely accidental.

Distribution and diversity. One species described below, but other, undescribed, species are known from northern South America east of the Andes, all from the Amazon Basin and Guiana Shield.

Included species (1):

Steinerlitrus warreni Gimmel , sp. nov. (Distribution: Venezuela)

Discussion. Although at least five undescribed species are known to me, I have described only one species in this publication to meet ICZN requirements. The genus will receive a dedicated treatment in the future.

Etymology. This genus is named in honor of Warren E. Steiner, Jr., of Cheverly, Maryland, USA, the world’s greatest phalacrid collector, together with the ending - litrus because of its superficial similarity to members of Eulitrus . The gender of the name is masculine.

Figures

FIGURE 36. Steinerlitrus warreni, male. (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 = 0.5 mm). (g) Metendosternite (scale bar = 1.0 mm). (h) Tegmen, ventral; (i) penis, ventral (scale bar = 0.5 mm). Female. (j) Spermatheca (scale bar = 0.5 mm).

FIGURE 43. Photographs. Paracylomus asiaticus: (a) dorsal; (b) ventral. Steinerlitrus warreni: (c) head and pronotum laterally, showing posterior eye emargination; (d) dorsal; (e) ventral. Eulitrus estriatus: (f) dorsal.