Lechriopini Lacordaire, 1865: 149

Anzaldo, Salvatore S., 2017, Review of the genera of Conoderinae (Coleoptera, Curculionidae) from North America, Central America, and the Caribbean, ZooKeys 683, pp. 51-138 : 68-69

Lechriopini Lacordaire, 1865: 149

Classificatory history and current circumscription.

This tribe was originally characterized by Lacordaire (1865: 149) for the genus Lechriops by the rostral channel, which is closed (horseshoe-shaped) posteriorly to receive the rostrum and the linear, carinate femora that may or may not exceed the apex of the abdomen.

While a subclassification for the Lechriopini is not formally proposed here without also examining the South American genera, the following groups of genera are hypothesized to be related: the " Eulechriops genus complex", including Eulechriops , Macrolechriops Champion, 1906, Copturomorpha Champion, 1906, Cylindrocopturinus Sleeper, 1963, Coturpus R.S. Anderson, 1994, and Turcopus R.S. Anderson, 1994 and the " Macrocopturus genus complex", including Macrocopturus , Copturomimus Heller, 1895, Lechriops , Pseudolechriops , Hoplocopturus Heller, 1895, and Mnemynurus Heller, 1895. The genera Microzygops , Paramnemyne , Poecilogaster , Euzurus , Copturus , Microzurus and Psomus do not fit into either complex as currently conceived. Until the inclusion of the South American lechriopine genera a subtribal classification for the Lechriopini will not be further speculated here.

Variation in key character systems.

Among the genera currently placed in the tribe (sensu Lyal et al. 2006), the only characters that distinguish them (after the exclusion of Acoptus , Philinna , and Philides ) are a concealed pygidium with rapidly ascending abdominal sclerites, the presence of modification to the mesoventrite and/or the presence of sclerolepidia (just sclerolepidia in Copturomimus , most Macrocopturus and Psomus ). The mesepipleura are usually large and somewhat ascending (except in Paramnemyne and Psomus ). Other characters given by Lyal et al. (2006: 229) that separate lechriopines from zygopines are: "larger eyes, extending half-way or more down the side of the head; a longer rostrum, reaching at least the middle coxae; the middle and hind femora with the posterior distal margin extended into an acuminate projection extending beyond the anterior distal margin", but these appear to be homoplastic - many lechriopines, especially some Eulechriops and related genera, have smaller eyes like many zygopines, and many zygopines have a similar femoral apex. The presence of a carina and ventral tooth on the hind femora, and the relative lengths of the first two funicular articles are potentially indicative of infratribal relationships; in the Eulechriops genus complex the hind femora are not carinate and unarmed ventrally and the second funicular article is at most subequal to the first, while in the Macrocopturus genus complex the hind femora are ventrally toothed and carinate and the second funicular article is longer than the first.

Modification to the meso- and metaventrite to receive the rostrum varies quite a bit in this group, with the typical forms (i.e. deviating the least from Lacordaire’s original tribal construction of a closed, horseshoe-shaped channel), being found in most members of the following genera: Lechriops , Poecilogaster , Eulechriops , Macrolechriops , Copturomorpha , Coturpus , Turcopus , Copturus , Microzurus , Euzurus , Microzygops and Pseudolechriops . These genera likely do not represent a monophyletic group, and the mode of closure (whether a simple depression or a strongly carinate apex of the channel) and the location of closure (on the mesoventrite or metaventrite) can vary significantly within genera. Pseudolechriops has arcuate lateral margins of the channel forming an ovoid carina that encircles a deep excavation on the mesoventrite and the anterior margin of the metaventrite (Fig. 13 ). A few species of the genus Macrocopturus (e.g. M. albidus Champion, 1906) and the genus Microzygops have a similarly constructed mesoventrite (Fig. 11 ) but the majority of Macrocopturus species and the very similar Copturomimus species have the unmodified "zygopine type" of mesoventrite. The mesoventrites of the genera Hoplocopturus and Mnemynurus are interpreted as of the lechriopine type, with the sides of the channel strongly arcuate and meeting medially, forming an inverted U-shaped carina that no longer appears to serve the function of receiving the rostrum (Fig. 9 ). Paramnemyne , Euzurus , Copturus , and Microzurus have a mesoventrite that would be classified here as the piazurine type ( Heller 1895: 5 also notes the resemblance), with the rostral channel on the mesoventrite open (in Paramnemyne and Euzurus , Figs 8 , 12 ) or closed (in Copturus and Microzurus , Fig. 6 ) and without anteriorly extending carinae; at least the latter three genera likely belong in the Lechriopini considering other characters. The mesoventrite of Psomus is unmodified.

Diversity and distribution.

Two hundred and forty-two species are currently known from north of South America in nineteen genera, comprising nearly half of the genus- and the majority of the species-level diversity of North and Central American Conoderinae . An additional eight genera are known only from South America.

Figures

Figures 10 - 18. Variation in the mesoventrite. 10 Lechriops californicus [ASUHIC 0024146] showing relatively parallel carinae marking the lateral margin of the rostral channel and a closure of the channel on the metaventrite 11 Microzygops nigrofasciatus [ARTSYS 0000797] with tubercles anterior to the mesocoxae and slight, arcuate carinae on the anterior region of the mesoventrite (encircling the central scaled region) 12 Paramnemyne decemcostata [ARTSYS 0000798] showing tuberculate posterolateral margins of the mesoventrite and a transverse carina near the posterior margin of the metaventrite 13 Pseudolechriops klopferi [SSAC 0001060] showing a deep ovoid receptacle on the meso- and metaventrite 14 Turcopus viscivorus [ARTSYS 0000530] showing a receptacle on the mesoventrite with prominently carinate posterior margin 15 Lissoderes subnudus [SSAC 0001066] showing a completely unmodified mesoventrite covered with multifid setae 16 Peltophorus adustus [ASUHIC 0031514] showing a ventrally expanded posterior margin of the mesoventrite to receive the rostrum in repose 17 Philenis fuscofemorata [ARTSYS 0000659] with tubercles at the posterolateral margins of the mesoventrite and a deep depression at the posterior margin in between 18 Philinna bicristata [ARTSYS 0000799] showing slight lamellate processes at the posterolateral margins of the mesoventrite as well as transversely flattened projections behind the procoxae.

Figures 1 - 9. Variation in the mesoventrite. 1 Trichodocerus brevilineatus [ARTSYS 0000616] showing a prosternal rostral " sheath " with the sides converging below the procoxae, the transverse ridge anterior to the mesocoxae and the region of the mesoventrite posterior to the ridge with dense yellow scales 2 Lobops bonvouloiri [ARTSYS 0000527] showing a cup-shaped receptacle for receiving the rostrum 3 Piazurus trifoveatus [SSAC 0001118] with an " open " channel on the mesoventrite 4 Pseudopinarus condyliatus [SSAC 0001116] with an " open " channel on the mesoventrite 5 Acoptus suturalis [ASUHIC 0016914] showing a flat, unmodified mesoventrite 6 Copturus sanguinicollis [ASUHIC 0086638] showing a closed receptacle on the mesoventrite with lateral flanges 7 Cylindrocopturinus pictus [SSAC 0001288] showing a rostral channel of the mesoventrite formed by relatively parallel carinae and no posterior termination 8 Euzurus ornativentris [ARTSYS 0000796] 9 Hoplocopturus javeti [SSAC 0001289] with an inverted U-shaped carina and the region posterior to the carina invaginated.