Merma Weise, 1898

Szawaryn, Karol & Churata-Salcedo, Julissa, 2022, Revision of Malagasy species of the genus Merma Weise (Coccinellidae: Epilachnini), Zootaxa 5087 (4), pp. 571-582 : 572-573

Genus Merma Weise, 1898

Merma Weise, 1898: 123 . Type species: Merma limbata Weise, 1898 (by subsequent designation of Korschefsky 1931). – Tomaszewska & Szawaryn 2016: 60 (redescription).

Peralda Sicard, 1909: 114 . Type species: Peralda quadriguttata Sicard, 1909 (by monotypy). New synonym.

Diagnosis. Merma Weise is characterized by deep antennal grooves between eyes and mouthparts, elytral epipleuron usually with distinctly marked foveae for reception of tips of femora, mid and hind tibiae with oblique carina on outer surface in apical part, all tibiae without apical spurs, tarsal claw bidentate swollen at base or with distinct angulation, male tegmen with patch of setae on inner surface of penis guide, penis with capsule reduced and females with spermatheca attached at base of bursa copulatrix. Merma is similar to Tropha Weise by having deep antennal grooves, elytral epipleuron with distinct femoral foveae and tibiae with oblique carina, however, the latter possesses anteriorly produced prosternum partially covering mouthparts, distinct spurs on apices of tibiae (1-2-2) and females with coxites with distinct emargination on inner margin (entire in Merma ). Merma is also similar to Chazeauiana Tomaszewska et Szawaryn, 2015 (for validity of that genus name see remarks at the end of the article) but the later do not have grooves for reception of antennae and tibiae lacking apical oblique carina.

Remarks. Study of the Peralda quadriguttata holotype showed that it falls well within the diagnostic characteristics of the genus Merma thus it is proposed here to synonymize Peralda Sicard with Merma .

Distribution. Africa: Cameroon, Republic of the Congo, Republic of Côte d’Ivoire, Uganda; Madagascar.

Key to Malagasy species of Merma Weise

1. Body larger, about 4.5 mm in length, rounded in outline; elytral margin explanate and well visible from above; elytral epipleuron broad, more than three times as broad as metanepisternum; median part of metaventrite covered with just a few large punctures; abdominal postcoxal lines almost parallel to posterior margin of ventrite 1........ Merma hovana ( Sicard, 1907)

-. Body smaller, about 3.3 mm in length, more elongate in outline, elytral margin not explanate and invisible from above; elytral epipleuron narrow, less than two times as broad as metanepisternum; median part of metaventrite covered with numerous large punctures; abdominal postcoxal lines rounded, not parallel to posterior margin of ventrite 1.................................................................................................. Merma quadriguttata ( Sicard, 1909)