Paracylomus Gimmel, 2013

Gimmel, Matthew L., 2013, <strong> Genus-level revision of the family Phalacridae (Coleoptera: Cucujoidea) </ strong>, Zootaxa 3605 (1), pp. 1-147 : 119-120

33. Paracylomus Gimmel , gen. nov.

( Figs. 35 ; 43a, b )

Type species: Acylomus asiaticus Champion , here designated.

Type material. Acylomus asiaticus Champion : lectotype, here designated in order to stabilize the species and new genus name, “ Ceylon [underlined with yellow] \ G. Lewis. \ 1910—320. // Horton Plains. \ 6,000 ft. \ 18-20. III.82. // 20.3.82 [handwritten] // Type \ H. T. [red-bordered disc] // Acylomus \ asiaticus \ type Ch. [handwritten] // cox. lines angular \ + sterna as in \ S. geminus [handwritten] // Acylomus \ asiaticus, \ Champ. // E.M.M. 1924. \ det. G.C.C. // SYN- \ TYPE [blue-bordered disc] // LECTOTYPE \ Acylomus \ asiaticus Champion \ des. M.L. Gimmel 2011 [red label]” ( BMNH). Paralectotype card-mounted upside down, with same locality labels, label added “ PARALECTOTYPE \ Acylomus \ asiaticus Champion \ det. M.L. Gimmel 2011 [yellow label]” ( BMNH).

Diagnosis. Recognized by a combination of the following features: elytra with two engraved sutural striae, metaventral process lobed and extending anteriorly beyond mesocoxae, metaventral postcoxal lines separated from mesocoxal cavities, protibia without ctenidium, and metatarsomere I shorter than II.

Description. Small, total length 1.7–1.9 mm. Dorsal color dark reddish-testaceous ( Figs. 43a, b ). 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 emarginate above antennal insertion; clypeal apex arcuate-truncate. Antennal club 3- segmented, club weakly asymmetrical, antennomere XI weakly turbinate ( Fig. 35b ). Mandible ( Fig. 35a ) with apex tridentate; without retinaculum; mandible without ventral ridge. Maxillary palpomere IV fusiform, short, nearly symmetrical; galea short, rounded; lacinia with two stout spines. Mentum with sides divergent toward apex; labial palpomere III fusiform. Labrum with apical margin arcuate. Gular sutures short, barely evident .

Thorax. Pronotum without obvious 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, not conspicuously setose preapically, without spinelike setae at apex. Protrochanter without setae; protibia without ctenidium on kickface. Scutellar shield small. Elytron with weak spectral iridescence; two sutural striae present, convergent in apical fourth of elytron; discal striae barely suggested; without transverse strigae; lateral margin with row of tiny, sawtooth-like setae. Mesoventral plate ( Fig. 35f ) notched anteriorly, extending posteriorly to metaventrite, dividing mesoventral disc in two, not forming procoxal rests; mesanepisternum with incomplete transverse carina; mesocoxal cavities widely separate, separated by more than half width of a coxal cavity. Mesotarsomere III not bilobed. Metaventral process ( Fig. 35f ) extending beyond anterior level of mesocoxae, protruding and arcuately lobed anteriorly; metaventral postcoxal lines relatively weak, diverging from mesocoxal cavity margin, arcuate; discrimen short, extending less than halfway to anterior margin of metaventral process; metendosternite ( Fig. 35g ) 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, longest spur subequal in length to width of tibial apex; metatarsus long and slender, metatarsomere I shorter than metatarsomere II, joint between I and II rigid ( Fig. 35d ); metatarsomere III not bilobed. Hind wing ( Fig. 35e ) with distinct, ovate anal lobe; leading edge with incomplete row of long setae at level of RA +ScP; AA 3+4 apparent only basally, without crossvein to Cu; cubitoanal system unbranched apically; CuA 2 and MP 3+4 without distal remnants; r4 absent; flecks present in apical field just distal to rp-mp2; long transverse proximal sclerite and additional strong, irregular sclerite present 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 upright in repose; tegmen ( Fig. 35h ) with asymmetrical anterior margin and parameres separated by weak suture from basal piece, parameres with medial longitudinal division; penis ( Fig. 35i ) short, wide, with endophallic spicules, no large sclerites, apex simple; spiculum gastrale V-shaped, with arms free. Female ovipositor weakly sclerotized, palpiform.

Immature stages. Unknown.

Bionomics. One series was collected from a Malaise trap.

Distribution and diversity. Only one species, known from Horton Plains National Park, Sri Lanka, and a specimen simply labeled “ Ceylon ” (see map, Fig. 44d ).

Included species (1):

Paracylomus asiaticus (Champion, 1924) , comb. nov. ( Acylomus ) ( Distribution : Sri Lanka) (type!)

Discussion. Despite Champion’s notes to the contrary, the type species does possess (albeit weak) metaventral postcoxal lines that diverge from the coxal cavities, though they are smoothly and evenly arcuate. This species was originally described in Acylomus , but the anteriorly lobed metaventral process and two sutural striae on each elytron make it quite distinctive.

Etymology. From the Greek prefix para - (near) plus the genus Acylomus , with which this genus shares a number of characters and has been confused in the past. The gender of the name is masculine.

Figures

FIGURE 35. Paracylomus asiaticus, 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 = 0.5 mm). (h) Tegmen, ventral; (i) penis, ventral (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.

FIGURE 44. Collection localities. (a) Malagasmus thalesi distribution in Madagascar; (b) Malagophytus steineri distribution in Madagascar; (c) Antennogasmus cordatus distribution in southern Africa and Madagascar; (d) Paracylomus asiaticus distribution in Sri Lanka; (e) Platyphalacrus lawrencei distribution in Western Australia.