Crenitulus Winters, 1926

FIKÁýEK, Martin & VONDRÁýEK, Dominik, 2014, A review of Pseudorygmodus (Coleoptera: Hydrophilidae), with notes on the classification of the Anacaenini and on distribution of genera endemic to southern South America, Acta Entomologica Musei Nationalis Pragae 54 (2), pp. 479-514 : 502-503

Crenitulus Winters, 1926 , stat. restit.

Crenitulus Winters, 1926: 54 . Type species: Limnebius suturalis LeConte, 1866 (original designation).

Crenitulus: ORCHYMONT (1933: 202 , synonymized with Anacaena ).

Gentilina Hebauer, 2003: 112 , syn. nov. Type species: Paranacaena nitens Gentili, 1993 (original designation).

Gentilina: KOMAREK & BEUTEL (2007: 225 , synonymized with Anacaena ).

Anacaena suturalis group: KOMAREK (2005: 288), KOMAREK (2007: 162), FIKÁýEK & ENGEL (2011: 625); SHORT & FIKÁýEK (2013: 729).

Species included (all species are transferred to Crenitulus from Anacaena ):

Crenitulus attiguus (Orchymont, 1942) , comb. nov. – Peru

Crenitulus hirsutus ( Komarek, 2005) , comb. nov. – Costa Rica, Guatemala

Crenitulus nitens (Gentili, 1993) , comb. nov. – Australia: Queensland

Crenitulus paleodominicus (FikáÞek & Engel, 2011) , comb. nov. – Dominican amber

Crenitulus perpennus (Orchymont, 1942) , comb. nov. – Costa Rica

Crenitulus solstitialis (Kirsch, 1873) , comb. nov. – Central and northern South America

Crenitulus schoedli ( Komarek, 2005) , comb. nov. – Costa Rica

Crenitulus suturalis (LeConte, 1866) , comb. restit. – widespread in North, Central and South Americas

Diagnosis. Adults (partly based on KOMAREK 2005, 2007): Body attenuated posteriad; eyes anteriorly not emarginated by a canthus of frons, remnants of frontoclypeal suture not bent along anterior margin of eye; antenna always with 9 antennomeres; procoxae in many species with apparent strong spines (absent in C. solstitialis , weakly developed on some C. suturalis ); gula very narrow; mesoventrite only narrowly reaching anterior margin of mesothorax; elytron with subserially arranged punctures; meso- and metatarsi with few long swimming hairs on dorsal face (except in C. attiguus ); aedeagus very similar in all species of Crenitulus : phallobase ca. as long as parameres, without or with very weakly de¿ned broad manubrium; parameres acute apically, regularly convex on outer margin; median lobe slightly narrowing apicad, cut off apically, with very short apodemes; gonopore apical or subapical.

Larvae (partly based on ARCHANGELSKY & FIKÁýEK 2004): Nasale with ¿ve teeth, all of more or less the same size, the right one reaching furthest, the left one least projecting; epistomal lobes present, rather small, nearly symmetrical; antenna with rather long antennomere 3, sensorium thin and as long as antennomere 3; maxilla with short stipes and very long palpomere 1; mandibles symmetrical, with two large and one very small basal tooth; labium with long ligula, projecting further than labial palps; seta on inner margin of antennal socket brush-like apically; pronotum with lateral projections; each segment of thorax dorsally with complex set of sclerites, some of which bear sclerotized projections; tergite of abdominal segment 8 tri¿d posteriorly.

Comments. The most apparent shared character of all species of Crenitulus is the morphology of the aedeagus, which is extremely similar in all species included here in the genus. KOMAREK (2005) did not include A. perpenna into the Anacaena suturalis group (i.e. what is now Crenitulus ), but mentioned the resemblance of its aedeagus with members of the group. The same is true for A. nitens , which KOMAREK (2007) only commented as showing morphological af¿nities to A. suturalis group. Neither of these two species was included in the molecular analyses as DNA-grade material is not available at the moment. It is true that both aforementioned species differ in several aspect from the remaining species of Crenitulus : C. perpennus e.g. in the short terminal antennomere and transverse ridge of the mesoventrite; C. nitens in the mesoventrite without a median protuberance and the pubescence of the metafemur extending slightly further distad than in Neotropical species. However, both species share the aedeagal morphology, which is very characteristic for the genus, and also completely match the generic diagnosis provided above. For these reasons, we include them into Crenitulus .

During routine identi¿cation, both the Neotropial and Australian species may only be confused with the genus Anacaena . In the Neotropics, they may be easily distinguished from Anacaena by the metafemoral pubescence con¿ned solely to the base and anterior margin (see KOMAREK 2005: Figs 51, 55–57, 59 ) whereas the Anacaena species have the pubescence much more extending distad (less so in A. parvula , which may be easily distinguished from Crenitulus by the antenna having 7 antennomeres). The only Australian species of Crenitulus may be easily distinguished from Anacaena by the narrowly elongate, darkly-colored body (more globular, and at least in some species, pale-colored in Anacaena ) and by the antenna with 9 antennomeres (8 antennomeres in all Australian Anacaena ). In all cases, species of Crenitulus may be easily distinguished from Anacaena by the morphology of the aedeagus: parameres are apically pointed and the phallobase does not have a distinctly constricted basal portion (manubrium) in Crenitulus , whereas the parameres are apically more or less widely rounded in all New World and Australian Anacaena , and the phallobase bears a narrowly projecting manubrium in all Australian Anacaena .

Figures

Figs 49–61. Morphological details of adults of Pseudorygmodus Hansen, 1999. 49–52 – maxillary palpus, ventral view (49 – P.flintispangleri (Moroni, 1985), male; 50 – P.flintispangleri, female; 51 – P. versicolor sp. nov., male; 52 – P. versicolor, female). 53–56 – metatibia, ventral view (53 – P. flintispangleri, male; 54 – P.flintispangleri, female; 55 – P. versicolor, male; 56 – P. versicolor, female). 57–58 – labrum, dorsal view (57 – P.flintispangleri, 58 – P. versicolor). 59 – aedeagus of P. flintispangleri. 60–61 – male genitalia of P. versicolor (60 – aedeagus, 61 – sternite 9).