Lodinus Mulsant and Rey

Kamiński, Marcin Jan, Lumen, Ryan, Kanda, Kojun & Smith, Aaron Dennis, 2022, Phylogenetic status of some unique species representing Blapstinina Mulsant & Rey (Tenebrionidae: Blaptinae: Opatrini), and implications for continued study of the subtribe, Zootaxa 5093 (5), pp. 519-532 : 523-524

Genus Lodinus Mulsant and Rey stat. restit. Lodinus Mulsant and Rey, 1859: 195 .

Type species: Lodinus nigroaeneus Mulsant and Rey, 1859 (= Blapstinus punctulatus Solier, 1851 ), by monotypy.

= Austrocaribius Marcuzzi, 1954: 18 syn. nov. Type species: Austrocaribius venezuelensis Marcuzzi, 1954 , by monotypy.

Composition (3 species, Fig. 4 ). Lodinus araguae stat. et comb. nov. (Marcuzzi) ( Venezuela), L. punctulatus comb. nov. ( Argentina, Bolivia, Chile, Uruguay), L. venezuelensis comb. nov. (Marcuzzi) ( Colombia, Venezuela).

Diagnosis. While many Blapstinina possess overlapping characteristics, Lodinus can be distinguished from other genera through the combination of the following characters: unfused elytra, well-developed metathoracic wings, parameres with truncate apex ( Fig. 1 ), and median lobe widely projecting between the parameres with the part visible from above oval-elongate and the apex acuminate.

Future studies should concentrate on investigating female terminalia within Lodinus as the current study revealed a presence of a hook-like baculus of the 4th coxite in the case of L. punctulatus ( Fig. 3B ). Ovipositors of L. araguae and L. venezuelensis were not possible to investigate here due to a lack of specimens.

More specific features separating Lodinus from other Blapstinina genera are listed below:

Aconobius (Southwestern US): Densely setose dorsally and laterally fimbriate ( Aalbu & Triplehorn 1985). Lodinus lacks dense setae ( Fig. 2A, E, F ). Parameres of Aconobius evenly tapering towards apex ( Iwan 2004), truncate in Lodinus ( Fig. 1 , 3D ).

Ammodonus (North America, Central America, South America, and Caribbean Islands): Covered in flattened, scalelike setae (feature missing in Lodinus ). Mentum with visible median keel and exposed lateral wings. All other Blapstinina , including Lodinus , characterized by flat mentum ( Lumen et al. 2020).

Blapstinus (North America, Central America, South America, and Caribbean Islands): Only reliably distinguishable by differences in male genitalia morphology: median lobe within Blapstinus not widely projecting between parameres which are often fused together, and are not apically truncated (contrary to Lodinus with widely projecting median lobe and apically truncated parameres) ( Fig. 1 ). Parameres usually tapering in Blastinus (tridentate in B.grandis - B.tibialis species-group).

Cenophorus (Monotypic; Hispaniola): Fused elytra (flightless). Basal margin of pronotum interrupted in mesal 1/3 (basal margin complete in Lodinus ), while hind margin of pronotum is medially depressed below plane of scutellar shield (Ivie & Hart 2016). Apex of parameres not truncated (Ivie & Hart 2016).

Diastolinus (Caribbean Islands) : Clearly separated via rounded (not truncated) apex of parameres and fully fused elytra. See Hart & Ivie (2016a), Ivie & Hart (2016) for more details.

Conibiosoma (Monotypic; Southwest US): Lacks developed flight wings. Dense setal fimbriae on lateral margin of pronotum. With small tubercles on elytral intervals. Further separated from Lodinus through curvature in aedeagus in lateral view; sinuate in Conibiosoma ( Aalbu & Triplehorn 1985, Iwan 2004), arcuate in Lodinus ( Fig. 1 ).

Notibius (Southwest US and Mexico): Lacks developed flight wings. Dense setal fimbriae on lateral margin of pronotum. Foretibiae expanded and slightly curved (narrow and straight in Lodinus ). Aedeagus curvature sinuate in lateral view ( Iwan 2004).

Conibius (North and South America): Most plesiomorphic genus among flightless Blapstinina , and traditionally defined by lack of apomorphies reported for other genera ( Aalbu & Triplehorn 1985). Male genitalia variable among species currently included in Conibius ( Iwan 2004) . Reliably separable from Lodinus via flightlessness regardless of current monophyly.

Cybotus (Monotypic; North and Central America): Flightless; with dense setal patches on metasternum ( Aalbu & Triplehorn 1985, Morales-García & Lumen 2020). Aedeagal parameres evenly tapering towards apex ( Iwan 2004).

Goajiria (Caribbean Islands and South America): Elytra fused. Similar to Lodinus , Goajiria possess truncate paramere apices. Median lobe of Goajiria does not widely project between parameres (Ivie & Hart 2016). Additionally, male mesofemur with patch of golden setae on underside of basal portion in Goajiria (absent in Lodinus ).

Hummelinckia (Monotypic, Caribbean Islands) : Lacks metathoracic wings ( Marcuzzi 1954). Furthermore, according to Marcuzzi’s description, unlike Lodinus ( Fig. 2A, E, F ), Hummelinckia with strongly reduced scutellar shield. Lastly, basal and apical portions of male genitalia (in lateral view) sinuate in Hummelinckia (similar to Conibiosoma , Nocibiotes & Notibius ).

Nevisia (Monotypic, Caribbean Islands) : Elytra fused. Parameres sinuate (in lateral view) and tapered apically (Ivie & Hart 2016).

Nocibiotes , Tonibiastes , and Tonibius (North America): Lack fully developed wings and possess costate/elevated elytral intervals ( Aalbu & Triplehorn 1985).

Platylus (monotypic, Virgin Islands): Elytra fused (Ivie & Hart 2016). Compared to Lodinus , Platylus is well characterised by large body size (10.0– 12.5 mm) and oval body shape. Platylus also possess two well-defined apophyseal indentations on pronotal disc (Ivie & Hart 2016), absent in Lodinus .

Trichoton: Characterised by curved/bent protibiae ( Aalbu & Triplehorn 1985, Kamiński et al. 2019b). Densely covered with two types of setae, forming separated well-defined patches on pronotum and elytra ( Aalbu & Triplehorn 1985, Kamiński et al. 2019b, Lumen et al. 2019).

Ulus: Pronotum and elytra covered with setae and bearing lateral fimbriae. Foretibia dilated, ending in a distal ‘tooth’ ( Lumen et al. 2019). Appears to be only blapstinine with enlarged, membranous field on basal portion of aedeagal tegmen ( Lumen et al. 2019).

Xerolinus (North America and Caribbean Islands): Recently erected genus differs from Lodinus as follows (Ivie & Hart 2016, Hart & Ivie 2016b): wings absent or reduced; seventh and eighth elytral striae fused anteriorly. Parameres rounded apically.

Figures

FIGURE 1. Phylogeny of subtribe Blapstinina. Figured topology was recovered in maximum likelihood analysis using IQ- Tree. Ultrafast bootstrap values (1,000 replicates) (integers) and posterior probabilities (20 million generations) acquired in Bayesian analysis (decimals) are displayed in red. The three investigated Blapstinina species are displayed in blue. Male genitalia (1–4) of selected species (dorsal views) are illustrated on the left. Topologies of collapsed clades (‘remaining Opatrini’ & ‘Dendarini + Pedininini + Playtonotini’) are fully consistent with those presented in Lumen et al. (2020).

FIGURE 2. Morphology of studied Blapstinina species. Habitus photographs and diagnostic features. (A–C) Lodinus punctulatus comb. nov., (D–F) Lodinus araguae comb. nov., (G) Blapstinus tibialis, (H, I) Blapstinus grandis. (B) protarsus, (C) mesotarsus, (D) last 5 antennomeres, (I) apical tip of epipleura.

FIGURE 3. Morphology of female and male terminalia of selected Blapstinina species. (A–C) Lodinus punctulatus comb. nov., (D) Lodinus araguae comb. nov., (E, F) Blapstinus tibialis. (A, B, E) ovipositor, (C, F) genital tubes, (D) parameres. Abbreviations: ag—accessory gland, b—hooked baculus of c4, c1–c4—subsequent lobes of coxites, g—gonostylus, sp—sper- matheca, vag—vagina.

FIGURE 4. Distribution of Lodinus.