A revision of Cissidium Motschulsky (Coleoptera: Ptiliidae) with seventy seven new species Author Darby, Michael text European Journal of Taxonomy 2020 2020-04-02 622 1 188 journal article 22458 10.5852/ejt.2020.622 9cb3ea96-0ee4-40b4-8006-19b5fed80b46 3777282 9CD3B2CD-F072-4994-8CA9-24145D343401 Key to species in species group 3 1. Pronotum with two linear depressions composed of united foveolae (note: C. longum Darby, 2019 shows traces on one side of the pronotum of a short depression but is not treated in this section of the key, see below)............................................................................................................................. 2 – Pronotum without linear depressions................................................................................................. 6 2. Posterior corners of mid-keel rounded ( Fig. 48C ).............................................. C. dewhurst sp. nov. – Posterior corners of mid-keel with projecting angles ........................................................................ 3 3. Lateral margins of pronotum rounded ............................................................................................... 4 – Lateral margins of pronotum angulate............................................................................................... 5 4. Larger more rounded species...................................................................... C. globulum Darby, 2019 – Smaller, narrower species .................................................................................... C. murphyi sp. nov. 5. Mesoventral mid-keel elongate ( Fig. 56C ) ........................................................ C. mindanao sp. nov. – Mesoventral mid-keel square ( Fig. 55C ) .................................................. C. marshallae Darby, 2019 6. Pronotal disc with only a trace of foveolae .................................................. C. amazonicum sp. nov. – Pronotal foveolae covering the disc................................................................................................... 7 7. Lateral margins of pronotum angular ................................................................................................ 8 – Lateral margins of pronotum rounded ............................................................................................. 10 8. Mesoventral lateral margins rectangular, hind angles acute.......................... C. longum Darby, 2019 – Mesoventral lateral margins not rectangular .................................................................................... 9 9. Mid-keel very narrow at junction with collar......................................... C. amboroense Darby, 2015 – Mid-keel wide at junction with collar.............................................................. C. puncticolle sp. nov. 10. Elytra almost parallel-sided in posterior half....................................................................................11 – Elytra sinuate in posterior half ........................................................................................................ 12 11. Pronotum densely and finely foveolate ( Fig. 54B ) ................................................ C. mahleri sp. nov. – Pronotum sparsely and more coarsely foveolate ................................................... C. werneri sp. nov. 12. Mid-keel not joining collar anteriorly.............................................................................................. 13 – Mid-keel joining collar .................................................................................................................... 14 13. Smaller species length 0.6–0.7 mm , elytra shorter in proportion to pronotum .. C. itoi Sawada, 2008 – Larger species length 0.8 mm , elytra longer in proportion to pronotum ........ C. latum Sawada, 2008 14. Mid-keel almost parallel-sided, hind angles rounded....................................... C. pilosellum sp. nov. – Mid-keel not parallel-sided.............................................................................................................. 15 15. Mid keel tapering from wide base by collar to keel.................................. C. nomurai Sawada, 2008 – Mid keel otherwise ............................................................................................................................. 16 16. Mid keel with projecting hind angles ........................................................ C. pauxillum Darby, 2019 – Mid keel reduced to small fragments either side of medial extension of the collar ........................................................................................................... C. ikeuchii Sawada, 2008