Cissidium
Creators: name: Darby, Michael
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Ptiliidae
Cissidium

description: Key to the Cissidium species of Bolivia
Note: the form of the antennae, genitalia and mesoventrum provide the best means of distinguishing species. The pronotum is also helpful but requires very careful orientation so that it is viewed from directly above (some of the Figs. 2–9 are not viewed in this way). In normal view, when the pronotum slopes down at the front, the lateral margins can easily appear to be angled and/or to have straight edges particularly in the posterior half. Similarly, the tip of the aedeagus is best viewed from several angles to be sure of correctly determining the shape.
1. Mesoventrum perforated and collar full width of keel at junction (Fig. 44)................................. Dacrysoma
- Mesoventrum without visible perforation and collar reduced in width at junction................................... 2
2. Mesoventral keel in horizontal view with a clearly projecting hook (Fig. 34). Meso- ventrum extending anteriorly onto ventral surface of collar; collar with a posteriorly oriented keel close to lateral margins. Mesoventral keel between the mesocoxae parallel sided with a rounded tip (Figs. 10, 13)................................................................. 3
- Mesoventral keel in horizontal view without a projecting hook (Fig. 35). Posterior margin of collar with only small medial projection, mesoventral keel between the mesocoxae tapering to a point............................................ 4
3. Smaller species, pronotum narrow, lateral margins appearing distinctly bulbous anteriorly, antennomere 11 very long, unlike any other species (Fig. 25).......................................................................... tigrum
- Larger species, antennomere 11 much shorter............................................................. lisae
4. Posterior margin of pronotum with a distinct sinuation in front of the hind angle (Fig.14); antennomere 11 with a short median restriction so that the two parts are barely separated (Fig. 24). Male with a series of stout, blunt spines on abdominal ventrite VIII (Fig. 31)................................................................................ amboroensis
- Posterior margin of pronotum without, or with only a slight sinuation before the hind angles, two parts of antennomere 11 clearly separate...................................................................................... 5
5. Longer species> 0.90 mm ...................................................................... elongatum
- Smaller species <0.80 mm ............................................................................. 6
6. Pronotum shorter and broader, sides more sinuate (Fig. 18). Male abdominal ventrites VII/VIII with a series of stout setae on the posterior margin (Fig. 29)..................................................................... globosum
- Pronotum longer and narrower, sides less sinuate (Fig. 19). Males without stout setae on the poisterior margin of ventrites 7/8................................................................................................. petri
description: Published as part of Darby, Michael, 2015, Studies of Bolivian Ptiliidae (Coleoptera) 1: The genus Cissidium Motschulsky with six new species, pp. 179-190 in Zootaxa 3937 (1) on page 181, DOI: 10.11646/zootaxa.3937.1.9, http://zenodo.org/record/235062