Tarsobaenus letourneauae Leavengood, Pinkerton and Rifkind, 2022

Leavengood, John M., Pinkerton, Morgan G. & Rifkind, Jacques, 2022, Description of the new genus Tarsobaenus and three new species from Costa Rica (Coleoptera: Cleridae: Clerinae: Hydnocerini), Zootaxa 5138 (2), pp. 167-176 : 169-172

Tarsobaenus letourneauae Leavengood, Pinkerton and Rifkind , new species

http://zoobank.org/ urn:lsid:zoobank.org:act:D8B90C8E-903E-4A3C-BEBC-F29E99683E06

( Figs. 1–6 )

Holotype: Male. COSTA RICA: Limón Province: Sector Cerro Cocori, 30km N de Cariari, Finca de Elias Rojas , A. C. Tortuguero, 100m, V-1994, E. Rojas, L N 286000_567500 #2917 ( INBio) . Paratypes: 27 specimens. COSTA RICA: Guanacaste Province: Estac. Pitilla, 700m, 9km S Santa Cecilia, XI-1989, C. Moraga & P. Rios, L-N 330200, 380200 ( INBio, 1 f), Est. Pitilla, 700m, 9km S Santa Cecilia, III-1991, C. Moraga & P. Rios, L-N 330200, 380200 ( INBio, 1 m), Estac. Pitilla, 700m, 9km S Santa Cecilia, Malaise trap, 1988, GNP Biod. Survey, L-N 330200, 380200 ( FSCA, 1 f; INBio, 2 f), Estac. Pitilla, 700m, 9km S Santa Cecilia, P. N. Guanacaste, 31-III-15-IV-1992, C. Moraga, L-N 330200, 380200 ( INBio, 1 f). Heredia Province: 11km ESE La Virgen, 250-350m, 10021 ’N 84003 ’W, 18-IV-2004, INBio-OET-ALAS transect, Malaise, 03/M/07/087 ( INBio, 1 f), La Selva, 18-21-I-1998, F. Hovore ( JNRC, 1 f), La Selva B.S., 50-150m, Locality: STR, 29-II-1986, Gerardo Vega ( JNRC, 1 f), Puerto Viejo de Sarapiqui , La Selva Biological Research Sta., 25-VIII-2010, J. M. Leavengood, Jr. ( JMLC, 1 f), Puerto Viejo de Sarapiqui , La Selva Biological Research Sta., 13-VIII-2010, J. M. Leavengood, Jr. ( JMLC, 1 m). Limón Province: Sector Cerro Cocori, Fca. de E. Rojas, 150m, 12-31-VIII-1992, E. Rojas, L-N 286000, 567500 ( FSCA, 1 f; INBio, 1 f), Sector Cerro Cocori, Fca. de E. Rojas, 150m, [??]-I-29-II-1992, E. Rojas, L-N 286000, 567500 ( INBio, 1 m), Sector Cerro Cocori, Fca. de E. Rojas, 150m, 26-VII-2-VIII-1992, E. Rojas, L-N 286000, 567500 ( JNRC, 1 f), Sector Cerro Cocori, Fca. de E. Rojas, 150m, XI-1991, E. Rojas, L-N 286000, 567500 ( INBio, 1 f), Sector Cerro Cocori, Fca. de E. Rojas, 150m, X-1991, E. Rojas, L-N 286000, 567500 ( INBio, 1 f), Sector Cerro Cocori, Fca. de E. Rojas, 150m, 26-VI-16-VII-1992, E. Rojas, L-N 286000, 567500 ( INBio, 1 f), Sector Cerro Cocori, Fca. de E. Rojas, 150m, I-1992, E. Rojas, L-N 286000, 567500 ( CSCA, 1 f; INBio, 1 f), Sector Cerro Cocori, Fca. de E. Rojas, 150m, I-1993, E. Rojas, L-N 286000, 567500 ( JNRC, 1 f), Sector Cerro Cocori, Finca de Elias Rojas , A. C. Tortuguero, 150m, VI-1993, E. Rojas, L N 286000, 567500 #2917 ( INBio, 1 f), Sector Cerro Cocori, Finca de Elias Rojas , 150m, IX-1993, E. Rojas, L N 286000, 567500 #2347 ( FSCA, 1 m; INBio, 1 f), Sector Cocori, 30km N de Cariari, Finca de Elias Rojas , A. C. Tortuguero, 150m, I-1994, E. Rojas, L N 286000, 567500 #2549 ( INBio, 1 f), Sector Cocori, 30km N de Cariari, Finca de Elias Rojas , A. C. Tortuguero, 150m, VI-1994, E. Rojas, L N 286000, 567500 #2549 ( INBio, 1 m), Sector Cocori, 30km N de Cariari, Finca de Elias Rojas , A. C. Tortuguero, 100m, II- 1994, E. Rojas, L N 286000, 567500 #2608 ( INBio, 1 f) .

Description: Holotype (male). Body length: 5.35 mm. Head, scape and pedicel, mouthparts, thorax, legs, basal tarsomeres, elytra and abdomen bright yellowish-testaceous; apical tarsomeres and antennomeres III-VI somewhat infuscate (darkening apically), mandibles weakly infuscate basally, pale in central portion, darkest at apices. Antennomeres VII-X black; metathoracic macula near metacoxa with a black macula; apical third of elytra gilvous at apices; dorsum with black markings as follows: head with basomedial macula, pronotum with medial longitudinal vitta, posterior margin of pronotal collar with transverse border, entire scutellum, elytra with small macula at humeral angle, elytral suture from scutellum to midelytral fascia, midelytral fascia broad and complete. Head: Slightly wider than humeri; surface smooth, impunctate, moderately covered in fine, long, pale, erect, semirecumbent setae; setae on eyes and posterolateral margin of head (behind eyes) longer; eyes prominent, width across eyes distinctly wider than at pronotal tubercles, sparsely clothed with fine, long, erect, pale setae. Antennae 10-segmented with distinct single-segment club. Frons with two dorsally convergent elongate depressions. Mouthparts with clypeus longitudinally subdivided; mandibles bifid, right mandible dorsally excavated to receive the left; apical maxillary palpomeres securiform; apical labial palpomeres digitiform. Thorax: Pronotum distinctly widest at lateral angles but narrower than width of head, covered in long, erect, pale setae interspersed with short, pale, semirecumbent setae; pronotal disc shiny, sparsely, finely punctate; punctures obsolete on anterior and posterior pronotal collars; disc very convex, anterior collar strongly constricted, upturned at head, transverse impression complete, anterior fringe of short, pale, erect setae projecting over head; posterior collar abruptly curved upward at scutellar margin; posterior collar with fringe of long, pale, erect setae projecting over scutellum; scutellum with long, pale, erect setae projecting over base of elytral suture. Ventral prothorax sparsely covered with long, fine, suberect setae which become shorter and more recumbent towards middle; procoxal cavities open; mesothorax densely covered with white recumbent setae; metepisternum similarly but less densely hairy; metathorax sparely covered with long, pale, erect setae. Metathorax large, somewhat inflated; surface smooth, minutely granulate, shiny. Legs: Surface shiny, covered with long, fine, testaceous, erect setae of varying length; femora expanded, weakly laterally compressed, nearly twice width of tibia, slightly wider distally; metafemora extending well past apex of elytra when projecting posteriorly; tibiae narrow, elongate, covered with long, fine, testaceous, erect setae of varying lengths, distal third with short fine, testaceous, semirecumbent setae, hind legs slightly longer but of similar form; tibial spur formula 1-2-2(?); tarsal claw bifid (ungues present). Wings: Elytra parallel to subparallel, widest at humeri, shiny, distinctly punctate with large, widely spaced punctures, barely covering abdomen, disc subflattened dorsoventrally, covered in long, fine, pale, erect, semirecumbent setae of varying lengths; internal margin of plica forming subulate excavation with distinct margin, dorsal margin of excavation black (consistent with midelytral fascia), ventral margin of excavation testaceous, projecting inward more so than dorsal margin; lateral margins weakly serrulate, each serrulate denticle with a single seta, serrulations strongest apically, more feeble anteriorly, obsolete in anterior third; strongly dehiscent in apical third beginning at posterior end of midelytral fascia where plica broadens noticeably, apices distinctly tumid, serrate-spicular, independently subtruncate, interior angles of truncation negligibly serrate. Hindwing dusky-testaceous radiating from venation, apical third entirely cloudy black, not covered by elytra, obscuring apex of abdomen dorsally. Abdomen: weakly shiny, sparsely covered with long, erect, pale setae; fifth sternite simple; sixth visible sternite entire, modified with lateral, inward-curved clasper-like appendages fused at middle; apical tergites unmodified. Females (paratypes) with a broad, gradual, smooth emargination on posterior margin of fifth sternite; sixth sternite divided longitudinally into two sclerites with widely-spaced, long, testaceous, subapical setae and dense apical fringe of shorter setae on each sclerite; apical tergite unmodified, but with pale setae of varying length, some subapical setae quite long and curved.

Diagnosis: Tarsobaenus letourneauae is readily distinguished from its congeners by its broad, black, midelytral fascia ( Fig. 1 ). Tarsobaenus hansoni also has a broad, black, elytral fascia ( Fig. 12 ) but in this species the band covers most of the anterior elytral ½, rather than being positioned medially.

Variation: Head sometimes markedly pale ivory between the eyes; basomedial macula on head sometimes absent or expanded into a vitta; small macula on the elytral humeral angle may be reduced or absent; apical elytral whitening is consistent with increased tumidity resulting in obscured punctation; males with elytra slightly more elongate-parallel, occasionally constricted at middle. The disposition of the abdomen in most specimens obscures measurements of body length.

Biology: The larvae of Tarsobaenus letourneauae occupy the petiole chambers of Piper cenocladum ( Piperaceae ), in which they feed on the lipid and protein-rich food bodies produced by the plant. The larvae also feed on adult and immature Pheidole bicornis Forel ( Hymenoptera : Formicidae ). They appear to chemically mimic their ant prey to induce food body production in the plant, which is normally a species-specific response to the presence of the ants ( Letourneau, 1990; Letourneau and Dyer, 1998; Dyer and Letourneau, 1999, 2003; Letourneau et al., 2004). These beetles have been observed in primary and secondary lowland rain forests at the La Selva Biological Station. Letourneau and Dyer (1998) reported the beetles as being most active in March and April. However, our specimen label data indicate most adult collection records occurred in January, August and September.

Distribution: Limón, Guanacaste and Heredia Provinces of Costa Rica.

Etymology: The patronym letourneauae honors Dr. Deborah Letourneau (University of California-Santa Cruz), the scientist who first discovered this species and first documented its interesting behavior.

Figures

FIGURES 1–6. Tarsobaenus letourneauae, n. sp. (paratypes): 1—dorsal habitus; 2—head; 3—male, ventral abdomen; 4—female, ventral abdomen; 5—elytral plica; 6—lateral habitus.

FIGURES 12–16. Tarsobaenus hansoni, n. sp. (holotype, paratype): 12—holotype, dorsal habitus; 13—head; 14—paratype, dorsal habitus; 15—elytral plica; 16—lateral habitus.