Carabhydrus Watts 1978
Creators: name: Hendrich, Lars
name: Watts, Chris H. S.
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Dytiscidae
Carabhydrus

description: Key to Species of Carabhydrus   
 1. Species smaller than 2 mm, median lobe in ventral aspect strongly tapered at apex (Fig. 26); NE QLD..................................................................................................................................................................................... C. storeyi sp.n.   
1'. Species longer than 2 mm............................................................................................................................................. 2  
2. Elytron more or less uniformly pale testaceous to reddish black to black, without basal or subbasal spots............... 6  
2'. Elytron black or brown except a large reddish subbasal spot and on some specimens also the apex.......................... 3  
 3. Species larger than 3 mm. Largest species of the genus (3.1–3.6 mm), pronotum more parallel sided (Fig. 2) and at base broader than head, with three deep longitudinal depressions on elytra, first mesotarsal segment in male formed like a triangular hook (Fig. 15); N NSW, S VIC.................................................................................... C. innae sp.n.   
3'. Species smaller than 3 mm, first mesotarsal segment in all known males without a triangular hook.......................... 4  
 4. Body flattened, more rounded, elytral grooves well defined and very deep, elytral spots less defined (Fig. 5), in female half of elytra covered by a fine microreticulation, male unknown; N NSW ............................... C. turaki sp.n.   
4'. Body more convex, elytral grooves less defined, elytral spots well defined (Figs 1, 3), in female only apex of elytra covered with fine microreticulation.............................................................................................................................. 5  
 5. Pronotum black (Fig. 1), aedeagus in ventral view with apex of each apical lobe sharply pointed and finger-like (Fig. 10); VIC, NSW, ACT.................................................................................................................................. C. andreas   
 5'. Pronotum reddish, only base of pronotum black (Fig. 3), male mesotibia with a well developed subapical tooth on inner edge, aedeagus in ventral view with apical lobes blunt and broadly rounded (Fig. 24); S QLD, N NSW.......... ...................................................................................................................................................................... C. plicatus   
6. Dorsal side pale testaceous or brown, eyes about half normal size or absent.............................................................. 7  
6' Dorsal side blackish-brown or black, eyes normal..................................................................................................... 8  
 7. Eyes present, ventral side pale to dark brown (Fig. 8), pronotum narrower than elytra in middle, basal part of median lobe with sclerotized, broad and shell-like coverage (Figs 16, 17), S NSW................................ C. janmillerae sp.n.   
 7'. Eyes absent, pale testaceous (Fig. 6), pronotum broader than elytra in middle, male unknown, stygobitic species; NSW ........................................................................................................................................................ C. stephanieae   
 8. Aedeagus in ventral aspect (Fig. 22) with a deep, broad, subapical notch on each side delimiting a broad, apically bilobed apex; VIC, NSW, TAS ......................................................................................................................... C. niger   
8'. Aedeagus in ventral aspect (Fig. 20) with a narrow subapical notch on each side, apex subtriangular and not broadly rounded......................................................................................................................................................................... 9  
 9. Elytron with mesal groove extending almost to apex; pronotum with lateral margin more or less evenly rounded except for short sinuation before posterolateral angle; aedeagus in lateral aspect lacking ventromedial projections (Fig. 21); NE QLD .................................................................................................................................. C. mubboonus   
 9'. Elytron with mesal groove shallow in apical third and discontinuous before apex; pronotum narrow, sides sinuate basally and more or less straight and parallel before posterolateral angles; aedeagus in lateral aspect (Fig. 19) with a pair of ventromedial projections; N NSW ................................................................................................. C. monteithi
description: Published as part of Hendrich, Lars & Watts, Chris H. S., 2009, Taxonomic revision of the Australian predaceous water beetle genus Carabhydrus Watts, 1978 (Col. Dytiscidae, Hydroporinae, Hydroporini), pp. 1-30 in Zootaxa 2048 (1) on pages 28-29, DOI: 10.11646/zootaxa.2048.1.1, http://zenodo.org/record/5323018