Lycomimus, Lawrence, John F. & Slipinski, Adam, 2013

Lawrence, John F. & Slipinski, Adam, 2013, Lycomimus, a new genus of Australian Ptilodactylidae (Coleoptera: Byrrhoidea), Zootaxa 3702 (1), pp. 71-78 : 71-76

Lycomimus gen. n.

Type species: Lycomimus bejsaki sp. n.

Diagnosis: This new genus is easily distinguished from members of the subfamily Cladotominae , including the Australian Austrolichas Lawrence & Stribling and several exotic genera such as Cladotoma Westwood , Paralichas White and Drupeus Lewis , by the 1) slightly transverse labrum, 2) distinct mandibular mola, 3) relatively broad galea and lacinia densely clothed with short, hooked, spine-like setae, 4) uninflated pronotum with incomplete lateral carinae, 5) unexcavated prosternum and 6) presence of gonostyli. It differs from members of the Ptilodactylinae , including Ptilodactyla , Pherocladus and a number of New World genera, such as Chaetodactyla Champion , Lachnodactyla Champion and Lomechon Wasmann , by the 1) non-articulated antennal rami in the male, 2) lacinia and galea of about equal width, 3) exposed protrochantins, 4) medial field of the hind wing with 5 free veins and a wedge cell, 5) simple pretarsal claws, 6) sternite IX in the male anteriorly rounded, 7) gonocoxites divided, and 8) gonostyli present. Lycomimus differs from those remaining Ptilodactylidae with lightly sclerotised maxillary lobes bearing one or more acuminate processes, such as Anchycteis Horn , Anchytarsus Guérin-Méneville , Araeopidius Cockerell , Byrrocryptus , Epilichas White , Octoglossa Guérin-Méneville and Pseudoepilichas Armstrong & Nakane , in having short, broad, more or less equally developed galea and lacinia, each densely armed with curved, spine-like setae. It also differs from all of these, except Pseudoepilichas in having a reduced fourth tarsomere. Species of the Australia-New Zealand genus Byrrocryptus resemble Lycomimus bejsaki in general appearance and in having somewhat similar mouthparts and antennae plus sharp but incomplete lateral pronotal carinae; however the tarsi in Byrrocrytpus are simple, without ventral lobes and with an unreduced fourth tarsomere. The blunt lacinia with a dense covering of curved spine-like setae also occurs in the Madagascar genus Daemon Laporte and the Neotropical genus Aploglossa Guérin-Méneville ; the former may be distinguished from Lycomimus by the complete lateral pronotal carinae coplanar with the anterior edge and the long, acute postcoxal projections of the hypomera, while the latter differs in having obsolete lateral pronotal carinae, no postcoxal projections, anteriorly simple scutellar shield and only four wing veins in the medial field. The South African genus Therius Guérin-Méneville differs from Lycomimus in having a well-developed, lobed fourth tarsomere, more or less complete but weakly defined lateral pronotal carinae and no postcoxal projections.

Description: Length about 6.3–7.8 mm. Body ( Fig. 1 A) elongate (BL/EW = 2.67–2.73), more or less parallelsided, very slightly wider at apical fourth; upper surfaces slightly convex; colour of head, most of prothorax, ventral surfaces, legs, antennae and mouthparts dark brown to black; mesal portion of pronotal disc, scutellar shield, and most of elytra yellow, elytral suture or posterior half of elytra sometimes black; vestiture of pronotum, scutellar shield and elytra consisting mainly of moderately long, thickened, decumbent golden hairs, mixed with finer, suberect hairs, the latter occurring mostly on darker, surfaces increasing the contrast between these and the bright yellow more densely pubescent surfaces; head, antennae, legs and undersurfaces clothed with short, fine, light yellow hairs.

Head moderately declined, almost as long as wide behind eyes; posteriorly biemarginate above occipital foramen; transverse occipital carina very weak extending for a short distance on either side of occipital foramen; vertex slightly convex, not sloping anteriorly. Eyes large, about 0.4 times as long as head, strongly protuberant, entire and finely facetted. Frontal region distinctly but not sharply declined; frontoclypeal suture distinctly impressed and broadly curved. Antennal insertions slightly exposed from above; subantennal grooves absent. Clypeus strongly transverse and apically truncate. Labrum about 0.6 times as long as wide, well sclerotised; sides straight, apically diverging to rounded apical angles; anterior edge slightly concave. Antennae ( Figs 1 A, 2B) in both sexes moderately long with elongate scape, very small pedicel, large, broad-based, flattened, non-articulated rami on antennomeres 3–10 and long, slender antennomere 11. Mandible ( Fig. 2 C) slightly longer than wide, more or less flattened, except at base; apex sharply bent towards midline and obliquely bidentate; molae well-developed, slightly asymmetrical (convex and concave) and transversely ridged; prostheca well-developed and densely fringed with setae. Maxilla ( Fig. 2 D) with lacinia slightly wider than galea, both relatively short and densely clothed with curved spines; maxillary palp relatively short, apical palpomere slightly longer than wide, asymmetrically widened apically with slightly rounded apex. Mentum about 0.42 times as long as wide, widest at base, apex slightly convex; ligula short and broad, bilobed and densely setose; apical labial palpomere very strongly, asymmetrically widened, much wider than long with slightly rounded apex. Subgenal ridges weak and slightly curved; gulamentum elongate, without transverse impression; gular sutures widely separated, continuous anteriorly with subgenal sutures, which extend to maxillary articulations; gula about 0.65 times as long as wide. Corpotentorium slender, slightly arched; laminatentoria almost meeting at midline. Cervical sclerites well-developed, undivided, gradually expanded posteriorly.

Pronotum ( Figs. 1 A–B) 0.57–0.63 times as long as wide, widest behind middle; sides sinuate forming slight anterior constriction; lateral carinae sharply defined but incomplete anteriorly; anterior edge subtruncate; posterior angles slightly acute; posterior edge triemarginate and crenulate, with well-developed accessory posterior ridge beneath, which is broadest laterally and forms part of pro-mesothoracic interlocking mechanism; disc slightly convex, not anteriorly inflated, slightly impressed posterolaterally. Prosternum in front of coxae ( Fig. 1 B) about 0.85 times as long as mid length of procoxal cavity, moderately convex; anterior edge subtruncate, with narrow head rest above; prosternal process long and narrow, sides converging to about middle, then parallel to apex, which is narrowly rounded. Procoxae projecting, distinctly carinate forming weak plate apically; trochantin broadly exposed. Procoxal cavities strongly transverse, externally broadly open (postcoxal projections of hypomeron short and acute), internally open. Notosternal sutures complete; hypomeron slightly impressed posteriorly.

Scutellar shield abruptly raised at base, more or less pentagonal in shape; cordiform, its anterior edge with median notch; apex narrowly rounded. Elytra about 2.19–2.24 times as long as wide and 4.38–4.65 times as long as pronotum; sides subparallel, although slightly wider at apical fourth, with conjointly rounded apices; anterior edge with distinct carina above a narrow, transverse concavity; disc slightly convex, with about 10 impressed striae and a scutellary striole (lateral striae very weakly defined); epipleuron moderately broad, narrowing posteriorly and complete to apex. Mesoventrite separated by sutures from mesanepisterna which are widely separated from one another; anterior edge on same plane as metaventrite, with pair of slightly declined procoxal rests continuing onto mesanepisterna. Mesoventral cavity relatively shallow, not extending beyond anterior edges of mesocoxal cavities; mesothoracic discrimen more or less complete; mesoventral process narrow, with deep posterior cleft forming pair of projecting knobs fitting into cavities in anterior metaventral process. Mesocoxae projecting with exposed trochantins. Mesocoxal cavities separated by about 0.2 times shortest diameter of coxal cavity, laterally open (partly closed by mesanepisternum and mesepimeron). Metaventrite about 0.8 times as long as wide, strongly convex; discimen about 0.6 times as long as ventrite; anterior metaventral process truncate, with small pair of anterolateral cavities for receiving mesoventral processes; transverse (katepisternal) suture very short but crossing discrimen; exposed portion of metanepisternum about 3.3 times as long as wide, widest near anterior end and gradually narrowing posteriorly; metepimeron slightly exposed. Metacoxae strongly transverse, about 0.4 times as long as wide at base, and strongly oblique, very narrowly separated and extending laterally to meet elytra, with weak coxal plates, widest mesally and almost obliterated laterally. Metendosternite long, narrow stalk, very small anteroventral projections, short lateral arms and well-developed anterior process bearing widely separated tendons. Hind wing ( Fig. 2 A) about 2.65 times as long as wide; moderately heavily pigmented; apical field 0.40 times as long as total wing length, with single weakly defined anterior oblique sclerite; radial cell about 3.6 times as long as wide with apical edge weakly rounded, basal edge straight and strongly oblique and inner posterobasal angle acute; cross-vein r3 moderately long and very slightly oblique; r4 complete and somewhat angulate at middle; basal porton of RP moderately long, extending to basal third, apical extension absent; R-M loop straight and acute; medial spur straight and extending to wing margin, where there is a slight embayment. Medial field with 5 free veins; MP3+4 with moderately long cross-vein and short spur; wedge cell about 0.2 times as long as greatest width of wing, 0.4 times as long as wide, obliquely truncate at apex and located close to wing margin; CuA1+2 moderately long and arising from cell at about middle; CuA1 somewhat longer and joining MP4 just beyond fork; AA4 relatively short, not reaching wing margin; anal lobe well-developed, without embayment.

Legs long and slender; trochanterofemoral joint strongly oblique, but with femur at least slightly separated from coxa; fore legs shortest, with femur and tibia subequal in length; mid and hind legs longer, with tibia somewhat longer than femur; mesofemur in male ( Fig. 2 E) with slender, acute tooth at about middle; tibiae all more or less parallel-sided, densely clothed with short setae and spines; tibial spurs paired on all legs; tarsomere 1 longer than 2–4 combined, 2 slightly lobed beneath, 3 with distinct, distally projecting membranous lobe, 4 reduced and simple; pretarsal claws simple, moderately long, without obvious empodium.

Abdomen about 1.6 times as long as wide at base, with five ventrites, the first three of which are connate; first ventrite with narrow, subacute intercoxal process; ventrites 1–5 each with narrow laterally projecting shelf continuous with parasternites and interlocking with elytral epipleura; ventrite 5 in male strongly transverse, apically subtruncate, with narrowly rounded, densely setose median projection ( Fig. 2 D); ventrite 5 in female simple and evenly rounded at apex. Most tergites moderately heavily sclerotised. Spiracles located in parasternites. Anterior edge of sternite VIII in male broadly rounded, posterior edge slightly concave; tergite VIII strongly transverse, apically truncate, with pair of strongly oblique, almost transverse basal struts. Sternite IX elongate, broadly rounded anteriorly, more narrowly rounded posteriorly; tergite IX ( Fig. 3 E) strongly tranverse and undivided, truncate at apex; tergite X free, slghtly shorter than wide, subtruncate at apex. Aedeagus ( Fig. 3 F) about 3.3 times as long as wide, subequal in length to sternite IX, more or less flattened, with phallobase about 1.8 times as long as wide, symmetrical, anteriorly truncate, posteriorly deeply emarginate and broadly overlapping parameres, each about 6 times as long as wide, internally sinuate and apically acute; penis about 3.7 times as long as wide, widest at apical third, subacute at apex, with moderately long basal struts, which are fused to bases of parameres. Anterior edge of sternite VIII in female deeply biemarginate, with two short, subacute lateral processes and a long, slender fixed spiculum ventrale, posterior edge narrowly rounded; sternite VIII ( Fig. 3 C) slightly longer than wide, anteriorly deeply emarginate, posteriorly subacute. Ovipositor ( Figs 3 A–B) 5.5 times as long as wide; proctiger elongate, apically emarginate, with paired longitudinal baculi; paraprocts about 3.2 times as long as gonocoxites, with longitudinal baculi, separated from well sclerotised gonocoxites, each of which is divided into proximal and distal lobes of about equal length, distal lobe narrowing apically, acute at apex, with very short, subapical, palpiform gonostylus; vulvar sclerite elongate and lightly sclerotised.

Distribution: Northern New South Wales and southern Queensland.

Etymology: The name is derived from the genus Lycus (Lycidae) and the Greek mimos (Latin mimus), actor Gender masculine.

Figures

FIGURE 1. Ptilodactylidae. A – B, Lycomimus bejsaki gen. & sp. n.: A, holotype male, habitus, dorsal; B, L. bejsaki, prothorax, lateroventral, left coxa removed, showing exposed trochantin. C, Ptilodactyla angusta Horn, prothorax, lateroventral, left coxa removed, showing concealed protrochantin. D. Austrolichas monteithi Lawrence & Stribling, prothorax, lateral, right coxa removed, showing elevated prothoracic disc.

FIGURE 2. L. bejsaki, male: A, hind wing; B, antenna; C, right mandible, dorsal; D, right maxilla, ventral; E, mid leg, showing femoral tooth.

FIGURE 3. L. bejsaki: A – C, female; A, ovipositor, ventral; B, apex of ovipositor, ventral; C, Segment VIII, ventral. D – E, male: D, abdominal ventrites 4 and 5; E, abdominal apex, dorsal; F., aedeagus ventral.