Anaballetus, Newton & Švec & Fikáček, 2017

Newton, Alfred F., Švec, Zdeněk & Fikáček, Martin, 2017, A new genus and two new species of Leiodinae from Chile, with keys to world genera of Sogdini and Leiodinae from Chile and Argentina (Coleoptera: Leiodidae), Acta Entomologica Musei Nationalis Pragae 57 (1), pp. 121-140 : 124-129

Anaballetus gen. nov.

Type species. Anaballetus chilensis sp. nov.

Diagnosis. Anaballetus gen. nov. is defined by the following characters: (1) body moderately large (3.3–3.6 mm), highly convex, ovoid with elytra almost parallel-sided ( Figs 1A–B ); (2) head moderately broad with anterior margin of clypeus straight, margined by a distinct fine carina that extends laterally over the antennal insertions and inner margin of the eyes ( Fig. 1C ); (3) epistomal suture present internally, broadly curved, indistinctly indicated externally by fine groove; (4) labrum shallowly emarginate, the emargination deeper than one fifth of the labral width ( Fig. 1C ); (5) eyes bulging, almost hemisphaerical; (6) antennae 11-segmented with interrupted five-segmented club ( Figs 1H , 2B,D ), AVII, AIX and AX each with a shallow periarticular gutter, AIX and AX also with additional invaginations (shallow anteriorly but forming a deep two-chambered sensory vesicle posteriorly); (7) mandibles broad at base but without contiguous molae, with simple tips, left mandible with medial blade without tooth but with feeble emargination in the middle, right mandible with strong tooth proximally just beyond middle of blade ( Fig. 1E ); (8) galea narrow, its setose brush small and poorly developed, lacinia with apical tooth and long densely setose brush along mesal edge ( Fig. 1G ); (9) maxillary palpi 4-segmented, apical palpomere about twice as long as and slightly narrower than penultimate palpomere ( Figs 1G , 2C ); (10) labial palpi 3-segmented, short, apical palpomere approximately as long as thickened penultimate palpomere ( Fig. 2C ); (11) mentum trapezoidal, apex bordered and about half as wide as base ( Fig. 2C ); (12) gular sutures widely separated, only partially evident externally ( Fig. 2A ); (13) pronotal base not bordered ( Figs 1A–B ); (14) scutellum distinct, triangular ( Fig. 1A ); (15) pair of large abdominal-elytral binding patches consisting of rows of very fine teeth on either side of the mid-line of tergites VI and VII (next to last visible tergite) occupying more than half of tergite VII ( Figs 4A–E ), and on the corresponding area on the underside of elytra ( Figs 4F–H ); (16) anterior tibiae with long distinct tarsal groove dorsally ( Fig. 3B , trgr); (17) anterior coxae touching each other ( Fig. 3B ); (18) procoxal cavities nearly closed behind by notal process and proventrite that meet but are not fused to each other ( Fig. 3B ); (19) mesocoxae distant ( Figs 3A,C ); (20) mesoventrite nearly vertical between the mesocoxae and with low short longitudinal carina ( Figs 3C–D , msvc); (21) anterior process of metaventrite broadly rounded and bordered between mesocoxae ( Figs 3A, C ); (22) abdomen with five visible ventrites ( Fig. 3H ).

Etymology. The name of the genus is derived from Greek αναβάλλεται (= anaválletai) meaning postponed, because the genus had been discovered and mentioned many years ago by NEWTON (1985, 1998) and others; subsequently Z. Švec recognized the new taxon while examining a single female not suitable for description due to its sex (in litt. to Newton, 2002). Masculinum.

Discussion. The new genus can be easily differentiated from similar genera of Sogdini by the combination of the characters given in the key above. The abdominal-elytral binding patches are unique among described genera of Sogdini , but are similar to structures that occur in some members of the related family Agyrtidae ( NEWTON 1997: Figs 24–25). These patches should not be confused with the normal patches of much larger “wing folding setae” (actually unarticulated setiform projections: HAMMOND 1979) found on the dorsum of the abdomen in most flying beetles, which are present in Anaballetus gen. nov. at the sides of tergites V–VII ( Figs 4B–E ). This new genus and its single included species were previously referred to in publications as “Hydnobiini Genus D” in NEWTON (1985: 192) and NEWTON (1998: 83), “ Sogdini Undescribed Genus 3” in PECK et al. (2000: 45), and “ Sogdini Género 3 no descrito” in SOLERVICENS ALESSANDRINI (2014: 74), in all these cases identified by A. Newton. According to Mario Elgueta (in lit. to Newton, May 2016), this genus and species is also the “ Sogdini sp.” of GREZ et al. (2003: 16), and was also referred to by the manuscript name Hydnobius globulosus by GERMAIN (1911: 62) and JEANNEL (1957: 55). NEWTON (1985) noted that the genus was closely allied to three other genera of Sogdini , also undescribed, and referred to by him collectively as the “BCDE” group, with two genera in Australia (B, C) and one in New Zealand (E) in addition to the Chilean genus (D). He considered these genera to form a monophyletic group because they “have retained molar lobes on their mandibles (reduced in all other Hydnobiini [= Sogdini ]) and have unique elytral-abdominal interlocking patches”. Anaballetus gen. nov. is the first of these genera to be described, and does not strictly fit the above description because the mandibles do not have contiguous molar lobes like the other three genera, although the mandibular bases are broader than in other Sogdini . Clearly, further study and description of the other three new genera is needed to fully understand and document the origin and status of this group, but at present it can be said that the relationships of Anaballetus gen. nov. are to these other southern temperate genera from Australia and New Zealand, rather than to the two other Chilean genera or the numerous northern hemisphere genera of Sogdini .

Figures

Fig. 1. Anaballetus chilensis gen. & sp. nov., holotype (A–D) and female paratype (E–I). A–B – body in dorsal and lateral view; C – head in dorsal view; D – aedeagus in dorsal view; E – mandibles; F – labium; G – maxilla; H – antenna; I – ovipositor in ventral view. Scale bars: 1 mm applies to A–B, 0.25 mm to D–I.

Fig.2.Anaballetus chilensis gen.& sp.nov., paratypes (A–D – male; E – female).A – head in ventral view; B – antenna, ventral view; C – detail of mouthparts; D – detail of antennomere 11 in ventral view; E – hind wing. Not to scale.

Fig. 4. Anaballetus chilensis gen. & sp. nov., female paratype; abdominal-elytral binding patches.A–E – abdominal tergites (A–B – tergites V–VIII; C–E – details of cuticular structures of tergite VII). F–H – ventral surface of elytron.

Fig.3. Anaballetus chilensis gen. & sp. nov., male paratype.A – meso- and metathorax in ventral view; B – prothorax and anterior leg; C–D – detail of median part of meso- and metaventrite (C – ventral view; D – ventrolateral view); E – protarsus; F – mesothoracic leg; G – mesotarsus; H – metathoracic leg and abdomen.Not to scale.Abbreviations: msvc – mesoventral carina; prre – procoxal rests; trgr – tarsal groove of protibia.