Lucaina discoidalis Horn, 1885

Ferreira, Vinicius S. & Ivie, Michael A., 2018, A Review of the Nearctic Genus Lucaina Dugès, 1879 (Coleoptera: Lycidae: Lycinae: Calochromini), with Descriptions of Two New Species, The Coleopterists Bulletin 72 (3), pp. 393-406 : 401

Lucaina discoidalis Horn, 1885

( Figs. 3 , 10 , 14 , 18 , 24 , 26)

Lycaina discoidalis Horn 1885: 150 (lapsus calami). Leng 1920: 140 (in part, SW Texas only).

Lucaina discoidalis ; Kleine 1933: 105; Green 1950: 15 (in part, Texas records only); Arnett 1974: 2 (in part, Texas and Arizona); Poole and Gentili 1996: 298.

Type Material. 16 (lectotype photograph): Tex/ Lectotype; 3511/ Lucaina ; discoidalis ; Horn/ MCZ; Syntype; 33844/ LECTOTYPE; Lucaina discoidalis Horn, 1885 ; det V.S. Ferreira 2017 ( MCZC). A second specimen ( ENT 00521674) is hereby designated a paralectotype and so labeled: PARALECTOTYPE; Lucaina discoidalis Horn, 1885 ; det V.S. Ferreira 2017. Horn (1885) mentioned two specimens when describing this species, and the two syntypes are in the MCZC. The specimen labeled “LecotTYPE; 3511” (MZ specimen ENTO0033844) has never been validly designated as a lectotype. The specimen is a male and is hereby designated lectotype to preserve stability of nomenclature, in accordance with ICZN (1999) Art. 74.7. (lectotype photographs examined).

Diagnosis. Lucaina discoidalis is very similar to L. schini , differing from this species by the bicolored dorsum (vs. completely yellow in L. schini ) and the subparallel male genitalia with the median lobe slightly shorter than the parameres, broader apex, and longer ventral base of parameres ( Fig. 18 ). Males of L. discoidalis differ from males of L. greeni by the absence of modified setae on the femora (vs. modified setae on femora in L. greeni ) ( Figs. 14, 15 ).

Redescription of Adult. Width across humeri 2.5–3.0 mm; elytral length 6.0–8.0 mm. Dorsal color yellowish, with exception of a black longitudinal median stripe on pronotum, black coloration on inner margins of apical elytral 1/3 margins, tibiae, abdomen, and antennae, which are black ( Fig. 3 ). Head prolonged in short rostrum, with coronal sulci strongly prominent. Eyes small, finely faceted, not approximate ( Fig. 10 ). Mandibles short, slightly curved, connate to transverse, shortened labrum. Maxillary palpomere IV and labial palpomere III broad, notched apically. Antennae subserrate, dorsoventrally slightly flattened, inserted below eyes, with antenniferous tubercles pronounced. Antennomere I subconical, antennomere II about half length of I, antennomere III subequal in length to I, IV about 1/4 longer than III, V subequal to IV, antennomeres VII–XI gradually decreasing in length. Pronotum as long as wide, margins slightly pronounced, thin, angles rounded, with a pair of subtle oblique elevations arising from posterior lateral margins of pronotum. Elytra subparallel, lateral margins stout, with 4 elytral costae weakly visible, pubescence decumbent. Ventrite VII of females with a shallow notch on apical region, each side broadly rounded ( Fig. 24 ). Male genitalia subparallel, with median lobe slightly shorter than parameres, acuminate apically, apex broader, ventral base of parameres longer ( Fig. 18 ).

Distribution. South Texas, USA and Zacatecas, Mexico ( Fig. 26 ).

Material Examined. TEXAS. 26, 2♀: Terlingua , Tex; V-4-1979 / Coll. by W.F.; Chamberlain ( TAMU) . 16: Terlingua , Brewester ; Co., Texas, V- 4-1979 / W.F. Chamberlain ( TAMU) . 16: Terlingua , Brewester ; Co., Texas, V-4-1979 / W.F. Chamberlain ( MTEC) . 16: TEXAS: Brewster Co ; Big Bend Nat Park; Santa Elena Cyn.; IV-22/ 23-1953; M. Wasbauer ( EMEC) . 16: 26 mi. S.E.; Eagle Pass. Tex ; IV-11- 1950 / Beamers Stephen; Michener Rozens ( EMEC) . ZACATECAS. 16, 1♀: MEXICO: Zacatecas ; Concepcion del Oro; April 17, 1977; El. 6000’ Murray; Schaffner, Sweet ( TAMU) .

Notes. This species was confused by Green (1950) with L greeni . See Notes under that species for more information.

Figures

Figs. 1–7. Lucaina species, dorsal habitus. 1) L. schini (lectotype photograph from UNAM, used with permission); 2) L. marginata (lectotype); 3) L. discoidalis (lectotype photograph from MCZC, used with permission, ©President and Fellows of Harvard College); 4) L. bajacalifornica (holotype photograph from UNAM, used with permission); 5) L. greeni (holotype); 6) L. greeni (bluish black elytra); 7) L. milleri.

Figs. 8–13. Lucaina species, head, frontal view. 8) L. schini (lectotype photograph from UNAM, used with permission); 9) L. marginata (lectotype); 10) L. discoidalis (lectotype photograph from MCZC, used with permission, ©President and Fellows of Harvard College); 11) L. bajacalifornica (holotype photograph from UNAM, used with permission); 12) L. greeni (holotype); 13) L. milleri.

Figs. 14–15. Lucaina species, profemora of males. 14) L. discoidalis; 15) L. greeni.

Figs. 16–21. Lucaina species, male genitalia, ventral and dorsal views, respectively. 16) L. schini; 17) L. marginata; 18) L. discoidalis; 19) L. bajacalifornica (holotype photograph from UNAM); 20) L. greeni; 21) L. milleri.

Figs. 22–25. Lucaina species, female ventrite VII. 22) L. schini; 23) L. marginata; 24) L. discoidalis; 25) L. greeni.

Figs. 26–27. Maps of the distribution of: 26) Lucaina milleri, Lucaina schini, Lucaina marginata, Lucaina discoidalis, and Lucaina bajacalifornica; 27) Lucaina greeni.