Cistudinella^{Champion, 1894} (Figs. 1-4) is one of seven genera in the Neotropical tortoise beetle tribe Ischyrosonychini Chapuis, 1875 (Chrysomelidae: Cassidinae). It currently comprises 15 recognized species that range from Costa Rica to Bolivia and Argentina but most species occur in Brazil (Borowiec & Świętojańska 2002-2021). Hosts are documented for just four species and these are shrubs and trees of Cordia L. and Patagonula L. (Boraginaceae) (^{Fiebrig 1910}; ^{Windsor et al. 1992}; ^{Duckett & Moura 2002}; Świętojańska & Medeiros 2007; ^{Flinte et al. 2008}). Data on juvenile stages are reported for two species: a single illustration of the larva of Cistudinella obducta (^{Boheman, 1854}) by Fiebrig (1910) and subsequent larval descriptions by Świętojańska & Medeiros (2007), and the report of an egg mass of 40-60 eggs and larval aggregations for Cistudinella notata (Boheman, 1854) (Flinte et al. 2008). The larvae are diagnosed by the 16 lateral scoli (body projections); they are gregarious and together exhibit cycloalexic (ring) defense. Larvae have paired urogomphi and species vary in the materials of the shields they carry: exuviae only in C. obducta (Świętojańska & Medeiros 2007: Fig 22; Świętojańska 2009) or with feces in C. notata (Flinte et al. 2008:201).

This note reports Paraguay as a new country record for Cistudinella inanis (^{Boheman, 1854}) based on one adult specimen (Figs. 1 - 4) that was collected at: PARAGUAY: Itapua, Encarnacion, Hotel Tirol, -27.183437° -55.777372°, 820 ft elevation [250 m approx.], 24 - 29 October 2018, MV light, coll. Larry G. Bezark. The species was known before only in Brazil (Borowiec & Świętojańska 2002-2021). The specimen is 9 mm long and was collected under permit #0372, issued by the Museo Nacional de Historia Natural del Paraguay (Inventario Biologico Nacional). It is currently deposited in the first author’s collection which will eventually reside in the Richard Bohart collection, University of California, Davis, USA. The specimen keys easily to genus with the online key of Borowiec & Świętojańska (2002-2021). Cistudinella inanis is distinct within the genus with the combination of ovoid form (Figs. 1-3), projections of postero-lateral corners of the pronotum (Figs. 1, 4), and color pattern (Fig. 1).

Tortoise beetles are not often collected at lights, suggesting that the host plants may have been very close. The reported specimen was collected at a sheet that was placed behind a wing of hotel rooms facing a small remnant parcel of Atlantic Forest surrounded by agriculture and urban development. Other tortoise beetles collected during the expedition at this site are: Coptocycla (Psalidonota) contemta (Boheman, 1855), Ctesiella confusa (Boheman, 1855), Ctesiella ramosa Spaeth, 1926, Ischnocodia annulus (Fabricius, 1781) (all determined by RW), and a species of Chelymorpha Chevrolat, 1836 (determined by Michael Geiser, BMNH).

We report the fourth species of Cistudinella reported for Paraguay; the other three species in Paraguay use Boraginaceae hosts (^{Fiebrig 1910}; ^{Flinte et al. 2008}). The only other Ischyrosonychini species known from Paraguay is Eurypedus peltoides (^{Boheman, 1854}) (Borowiec & Świętojańska 2002-2021) also using Boraginaceae hosts (^{Silva et al. 1968}). Fiebrig (1910) reported on the biology of some Paraguayan species including immatures of Cistudinella obducta (Boheman, 1854). Contemporary documentation with new records, new species, range mapping, life cycle rearing, museum study, and especially targeted field collections and online resources (e.g., Barriga-Tuñón 2012-2022) will improve our knowledge of the Cassidinae of Paraguay.

Figures 1 4. Cistudinella inanis (Boheman) from Paraguay (photos: L. Bezark). 1. Dorsal view. 2. Ventral view. 3. Lateral view. 4. Frontal view.