Hermosacantha, Borowiec, Lech & Wietojañska, Jolanta, 2014

Borowiec, Lech & Wietojañska, Jolanta, 2014, A revision of the genus Herminella Spaeth (Chrysomelidae: Cassidinae: Notosacanthini), with a description of a new related genus and species from Madagascar, Zootaxa 3895 (2), pp. 257-272 : 268-270

Hermosacantha gen. nov.

Diagnosis. Very small cassids with length less than 2.5 mm. Pronotum transverse with well marked basal corners and broad but shallow anterior emargination, head not visible from above. Transparent margins of pronotum in anterior emargination never overlapped. Disc of pronotum with shallow basal impressions impunctate on sides with coarse and sparse punctures, surface of disc appears regular. Explanate margin of elytra with very large transparent punctures, disposed irregularly. Scutellum rectangular. Base of elytra as wide as pronotum. Elytral disc depressed with very coarse and dense punctures. Punctures tend to form longitudinal rows but on sides of disc irregular, interspaces distinctly narrower than puncture diameter thus intervals hardly visible or at most linear. Sculpture of disc not as developed as in most species of the genus Notosacantha , with rudiment of apical transverse costa, humeral costa and partly developed dorsal costa, no elevated tubercles. Explanate margin of elytra strongly declivous, narrow, not wider than 1/4 width of disc, with coarse and dense punctation, without impunctate, fenestrate spots. Head without frontal plate. Clypeus with large circular impression and deep median sulcus. Eyes small, gena longer than half width of eye. Labrum transverse, without or with very shallow anterior emargination. Prosternal collar very short. Prosternal process with deep median sulcus, between coxae not wider than half width of coxa, strongly expanded apically with truncate apex, in the widest part more than three times wider than between coxae, its surface without special sculpture. Meso and metasterna without modifications, sides of metasterna moderately convex. Abdomen without fusions of sternites. Legs stout, femora without teeth or spines, tibiae broad, slightly depressed laterally with sharp external margin. Tarsi broad with densely setose sole, last segment short, note extending behind margin of the third segment, claws symmetrical, simple. Antennae stout, 11-segmented with distinct 4-segmented club.

The genus Hermosacantha has all the characters of the tribe Notosacanthini and differs from the most species of the genus Notosacantha in very small body (most species of Notosacantha are larger, with length from 4 mm to 8 mm), with reduced elytral sculpture (most Notosacantha species have special set of elytral costae and tubercles), the lack of a frontal plate (most Notosacantha species have distinct frontal plate), with very narrow and strongly declivous explanate margins of elytra (in Notosacantha the margin is usually broad, moderately declivous to horizontal) and with very shallow emargination of anterior margin of pronotum. Members of Notosacantha have usually deep anterior emargination, transparent margins never overlapped and head more or less visible from above. Only five species of Notosacantha from Madagascar have the anterior emargination shallow and reduced frontal plate but head partly visible from above and body size from 4 to 6 mm and well marked elytral sculpture.

Members of the genus Herminella look at first glance very similar, they have a similar small body with narrow explanate margin of elytra, with a shallowly emarginate anterior margin of pronotum and the sculpture of disc with only short fragments of costae but differ in the anterior emargination of the pronotum without overlapped transparent margins. In Hermosacantha the emargination is very broad while in Herminella it is small and triangular.

The most distinguishing characters of Hermosacantha from both Herminella and Notosacantha is the peculiar structure of the clypeus with a large circular impression and a deep sulcus along the impression (in both related genera clypeus has a triangular median impression without a sulcus), the small eyes, and the prosternal process between coxae with deep a median sulcus (in both related genera the prosternal process is flat or with a shallow impression along the middle).

Type species. Hermosacantha madagascarica spec. nov. Gender: feminine.