A new genus of spider beetle (Coleoptera, Ptinidae) from western Peru Author Philips, T. Keith Systematics and Evolution Laboratory, Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101 - 3576, USA https://orcid.org/0000-0002-1190-4019 keith.philips@wku.edu Author Whorrall, Kyle A. Systematics and Evolution Laboratory, Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101 - 3576, USA Author Gearner, Olivia M. Systematics and Evolution Laboratory, Department of Biology, Western Kentucky University, 1906 College Heights Blvd., Bowling Green, KY 42101 - 3576, USA Author Huchet, Jean-Bernard Museum National d'Histoire Naturelle, UMR 7205 ISYEB, Institut de Systematique, Evolution et Biodiversite, 45, rue Buffon, F- 75005 Paris, France text ZooKeys 2020 934 81 91 http://dx.doi.org/10.3897/zookeys.934.38670 journal article http://dx.doi.org/10.3897/zookeys.934.38670 1313-2970-934-81 8E894A5075784CEABA6CC995776A2DE9 EA7BE9C2AA105FCE803A60AEA2E6A5A6 Cordielytrum Philips gen. nov. Figures 1 , 2 , 3 , 4 Type species. Cordielytrum peruvianum Whorrall & Philips. Diagnosis. This genus can be recognized by the heart-shaped pair of fused elytra and the dense appressed setal scale covering (Figs 1 , 2 ). There are also very elongate erect setae on the lateral edge of the pronotum and humeral area of the elytra that extend laterally and curve slightly posteriorly apically. Near the pronotal base are five depressions; one large median and two smaller ones positioned more laterally on each side. There is also a distinct and relatively large pocket on the head positioned below the eye and extending to the lateral edge of the clypeus. Currently the two species in this genus are known only from Peru. Figure 1. Cordielytrum peruvianum sp. nov. A Dorsal habitus B ventral habitus C lateral view D frontal view. Scale bars: 1.0 mm ( A, B ), 0.5 mm ( D ). Figure 2. Cordielytrum pulchrum sp. nov. A Dorsal habitus B ventral habitus C lateral view D frontal view. Scale bars: 1.0 mm ( A, B ), 0.5 mm ( D ). Description. Body : small, length approximately 2 to 2.5 mm, ovoid, convex but slightly flattened dorso-ventrally, dorsally body surface completely obscured with appressed or recumbent setae, scale-like especially on head and elytra. Head (Fig. 4A ): Eyes not visible dorsally, small, ovoid, slightly rounded ommatidial surface facing slightly upwards; vertex very slightly convex, antennal fossae generally indistinct, smoothly rounded edges, but more distinct dorsally and laterally absent; a large distinct pocket extending laterally from fossa through to gena between eye and lateral edge of clypeus; antennae short in length, no longer than the maximum width of the pronotum, 11 antennomeres, 4-10 relatively stout, only slightly longer than wide, second antennomere inserted off center of scape near lateral edge; interantennal space between antennal insertions wide, width approximately the same as length of scape, flat with no carina between antennal fossae; clypeus triangular, maximal width ≈ 4/5 width of head measured adjacent to pronotum, labrum (Fig. 4B ) ca. 1/3 width of clypeus, anterior edge very slightly emarginated in middle; mandible apex acutely pointed, medial tooth present (Fig. 4C ); maxillary and labial palps with four and three palpomeres respectively (Fig. 4D, E ); mentum triangular, with small triangular cavity at middle (Fig. 4F ). Pronotum (Fig. 3B ): Strongly transverse with five depressions adjacent to the posterior margin, one large median and two smaller laterally on each side (Figs 1A , 2A ); elongate erect setae on lateral edge extending laterally. Elytra (Fig. 3A ): Heart-shaped, convex, fused along suture; longitudinal carinae at least at base and sometimes visible the entire length of each elytron, short suberect setae on carinae; relatively elongate setae on humeral area that extend laterally and curve posteriorly near their apex; 2-3 irregular fine puncture rows between each carina. Thorax (Fig. 3D ): Broader than long; prosternal process narrow anteriorly, widening posteriorly, teardrop- shaped, extending posteriorly to same distance as procoxae do posteriorly, extending slightly into mesoventrite; visible part of mesoventrite heart-shaped with a truncate tip posteriorly, between coxae slightly longer than wide, slightly shorter than length of metaventrite at middle; posterior margin of metaventrite broadly emarginated; mesoventral-mesepisternal and metaventral-metepisternal sutures both visible. Abdominal ventrites (Fig. 3D ): Ventrites broad, ca. 2/3 total width of body measured at/opposite ventrite base, all sutures visible, first three ventrites connate, length at middle compared to laterally slightly shorter except fifth where longest at middle; first and second approximately equal in length, third slightly shorter, fourth distinctly shortest, fifth distinctly longest. Legs (Fig. 3B, D ): moderate in length, femora widest near middle; tibia gradually expanded toward apex, pro- and mesotibiae similar in length to their respective femora, metatibiae distinctly longer; tarsomeres 2-4 ca. as wide as long, 1st and 5th ca. equal in length; procoxae and mesocoxae approximately rounded, procoxae slightly smaller in diameter than mesocoxae, metacoxae transverse, fused with metaventrite. Male genitalia (Fig. 3C ): relatively simple; parameres and median lobe relatively stout, parameres lacking setal clumps or other modifications. Figure 3. Cordielytrum pulchrum sp. nov. A Elytra, dorsal view B prothorax, frontal view, C aedeagus, dorsal view D meso- and metaventrites and abdominal ventrites. Scale bars: 0.5 mm ( A, B, D ), 0.1 mm ( C ). Figure 4. Cordielytrum pulchrum sp. nov. A Head, frontal view B labrum, dorsal view C mandible, ventral view D maxilla, ventral view E labium, dorsal view F mentum, ventral view. Scale bars: 0.5 mm ( A ), 0.1 mm ( B-F ). Etymology. The generic name is derived from cordi = Latin for heart and elytrum = Greek for sheath in reference to the fused elytra that figuratively resemble an ideographic image of a heart. Remarks. Sexual dimorphism externally is not apparent. Distribution. Members of this genus appear to be denizens of xeric coastal areas in Peru (Fig. 5 ). Based on the locations of the two known species, there is a separation of over 700 km. Recent fieldwork in Peru has resulted in the collection of additional undescribed species in the south with one ca. 730 km straight line distance from Lima at ca. 17° latitude (Whorrall and Philips, unpublished). The discovery of even more undocumented species with further sampling should be expected. Figure 5. Distribution of Cordielytrum peruvianum (circle) and C. pulchrum (triangle). The position of the city of Lima is also indicated (star). Ecology. Currently no information on the ecology is known with the exception of the northernmost species that was collected via traps baited with a local corn beer known as chicha: this fluid may have been attractive as a food and/or moisture source. Based on recent collections and current rearing experiments (Philips and Whorrall, unpublished), larvae feed on cat dung and likely any other type in their vicinity, such as that from other mammals, birds, or lizards.