Lionothus Brown, 1937

Peck, Stewart B. & Cook, Joyce, 2013, Systematics and distributions of the genera Cyrtusa Erichson, Ecarinosphaerula Hatch, Isoplastus Horn, Liocyrtusa Daffner, Lionothus Brown, and Zeadolopus Broun of the United States and Canada (Coleoptera: Leiodidae: Leiodinae: Leiodini), Insecta Mundi 2013 (310), pp. 1-32 : 13

Lionothus Brown

Lionothus Brown, 1937: 170 . Type species: Lionothus ulkei Brown, 1937 ; by original designation. Daffner 1988: 288.

Pseudocyrtusa Portevin, 1942: 78 . Type species: Pseudocyrtusa australis Portevin, 1942 , by monotypy; synonymy by Newton 1983: 175.

Diagnosis. Body convex. Antenna with 11 antennomeres with 5-antennomere club interrupted at antennomere 8, which is narrow and disc-shaped but clearly visible. Mandibles variable, left mandible usually with one or two small blunt teeth on anterior one-third. Ventral side of head with or without well defined antennal grooves. Mesosternum vertical between mesocoxae, not carinate. Tibiae uniformly widened to apex; protibiae with tarsal grooves; outer margins of all tibiae with strong spines. Tarsal formula 5-5- 4 in both sexes. Abdominal sternites III–VII each with basal transverse row of large punctures. Males are distinguished by larger, often sinuate spur on inner apical margin of usually straight mesotibia; inner apical margin of mesotibia not produced; and apical tooth-like expansion of the lower margin of the metafemur.

Distribution. The distribution of the genus is Nearctic and northern Neotropical ( Mexico, Colombia) ( Newton 1998).

Key to species of male Lionothus of the continental United States and Canada

1. Male mesofemur with acute tooth-like expansion at apex of inner margin ..... L. ulkei Brown

– Male mesofemur without acute tooth-like expansion at apex of inner margin .......................... 2

2(1). Smaller species, total length (pronotum + elytra) less than 1.5 mm; apical antennomere as wide as penultimate antennomere ........................................... L. exiguus Peck and Cook , n. sp.

– Larger species, total length (pronotum + elytra) 1.8-2.6 mm; apical antennomere narrower than penultimate antennomere .......................................................................................................... 3

3(2). Antennal grooves well defined, outer margins demarked by carinae extending posteriorly beyond the eye ................................................................................................... L. forticornis Daffner

– Antennal grooves not well defined, outer margins not demarked by carinae ............................ 4

4(3). Mandibles short, together forming semicircle, left mandible with 2 small teeth on apical onethird; eye of normal size, about half length of head .. L. bidentatus Peck and Cook , n. sp.

– Mandibles elongate, not forming semicircle when closed; left mandible with single tooth near middle; eye reduced, about one-third length of head.................................................................. ..................................................................................... L. parvoculus Peck and Cook , n. sp.