Merma hovana ( Sicard, 1907 ) Szawaryn & Churata-Salcedo, 2022

Szawaryn, Karol & Churata-Salcedo, Julissa, 2022, Revision of Malagasy species of the genus Merma Weise (Coccinellidae: Epilachnini), Zootaxa 5087 (4), pp. 571-582 : 573-575

Merma hovana ( Sicard, 1907) comb. nov.

Figs 1–3

Epilachna hovana Sicard, 1907: 480 . Type locality: Baie d’Antongil.

Diagnosis. Colouration of Merma hovana is identical to M. quadriguttata , however, its body is larger and more rounded, with lateral elytral margin well visible from above, moreover, it has terminal labial palpomere transverse, widened apically, hypomeron and prosternum covered with sparse and small punctae, elytral epipleuron broad, more than three times broader than width of metanepisternum, median part of metaventrite covered with just a few large punctures, abdominal postcoxal lines almost parallel to the posterior margin of ventrite 1 with just apex recurved, and male genitalia heavily sclerotized with distinct additional thorns on inner surface of penis guide, and penis short, only slightly sinuate with large bent apical thorn. From the African species that also have four maculae on elytra it can be distinguished by distinctly smaller spots, while in African species they occupy at least half of elytral surface.

Description. Length 4.4–4.5 mm, width 4.1–4.2 mm. Body ( Fig. 1A–C ) roundly oval, strongly convex, dorsum pubescent. Head, mouthparts, legs and abdomen reddish-orange. Pronotum chestnut brown with narrow reddish bordering of anterior pronotal margins. Elytra chestnut brown, with two orange or reddish maculae on each elytron, the first placed below humeral callus, the second in apical part of elytron.

Head transverse, partially concealed in prothorax. Interocular distance about 0.6 times of head width. Inner eye orbits slightly emarginate antero-medially, closest in the middle. Antenna ( Fig. 2C ) composed of 11 antennomeres, about as long as 0.6 head width; scape large, elongate, slightly swollen; pedicel distinctly narrower than scape, elongate; antennomere 3 elongate, about as long as pedicel; antennomeres 4–7 elongate, about 1.5 times as long as its width; antennomere 8 slightly transverse; antennomeres 9–11 forming a distinct asymmetrical club. Ventral antennal grooves ( Fig. 2C ) distinct in anterior part, moderately long and straight, along inner margin of eye. Clypeus short, parallel-sided, its anterior margin emarginate, smooth without groove. Labrum transverse, short, anterior margin emarginate, membranous. Mandible ( Fig. 2B ) multidentate apically. Maxilla ( Fig. 2B ) with cardo semicircular; with suture between basistipes and mediostipes well visible; lacinia simple, its mesal surface simply setose; galea oval, mostly sclerotized, its ventral surface sparsely pubescent, anterior surface covered with long setae and sensillae; terminal palpomere shorter than its width, weakly expanded apically. Submentum short, transverse, with suture well visible; mentum ( Fig. 2B ) transverse, widest at base; prementum transverse with anterior margin emarginate medially, ligula covered with moderately long setae; labial palps (Fig. 55G) separated by distance less than width of palpiger; apical palpomere about as long and distinctly narrower than penultimate one.

Prothorax. Hypomeron smooth, simply / finely punctate. Prosternal process ( Fig. 2C ) smooth, without carinae, bordered laterally. Prosternum in front of coxa about as long as coxal longitudinal diameter; anterior margin, uniformly arcuate, bordered; posterior margin with bordering line starting from the base of prosternal process, laterally reaching notosternal suture. Surface of prosternum covered with sparse small punctae.

Pterothorax. Mesoventrite ( Fig. 2C ) with anterior edge weakly emarginate, anterior margin entirely raised and bordered, with shallow foveae for receiving mid legs; mesoventral process covered with small tubercles along lateral margins, about as wide as mesocoxal diameter; meso-metaventral suture straight. Scutellar shield triangular, about as long as broad. Elytra with punctate of two sizes; lateral margins distinctly explanate, entirely visible from above. Epipleuron complete ( Fig. 2A ), broad, more than three times broader than width of metanepisternum, with distinct depressions to accommodate mid and hind legs in repose, inner margin with broad bordering line present in median and apical part, complete. Mesoventrite covered with sparse and small punctures, with just a few larger in median part. Metaventral postcoxal lines ( Fig. 2D ) joined on metaventral process forming straight line, recurved, laterally complete.

Legs ( Fig. 2A ) short and stout with apices of mid and hind femora not protruding from outer margin of elytral epipleuron. Trochanters elongate, angulately produced, with bordering line on their outer surfaces, and cavities on their inner surfaces for receiving tip of tibiae in repose. Protibiae slightly widened, all tibiae on outer edge with oblique carina near apex, without distinct apical spurs. Tarsi pseudotrimerous with tarsal claws ( Fig. 2E ) double, swollen at base, empodium absent.

Abdomen with five ventrites in both sexes with ventrite 5 arcuate posteriorly ( Figs 2A , 3F ). Abdominal postcoxal lines ( Fig. 3F ) descending, sub-parallel to posterior margin of ventrite 1, recurved shortly laterally. In male apical margin of sternite VIII ( Fig. 3J ) and tergite VIII rounded ( Fig. 3I ); apodeme of sternum IX ( Fig. 3E ) rod-like, long, narrow. Tergite X transverse, truncate apically ( Fig. 3E ). In female apical margin of sternite VIII ( Fig. 3H ) rounded apically, simply arcuate at base, longitudinally at middle not divided; tergite VIII rounded ( Fig. 3G ). Proctiger (TX) large, transverse, slightly emarginate at apex, its median part translucent, membranous.

Male genitalia ( Figs 3A–C ). Tegminal basal piece with a pair of spines on inner margin near base of tegminal strut. Penis guide symmetrical in inner view, slightly longer than parameres, with apical half sub-triangular in shape, pointed, entire at apex; in lateral view outer edge sinuate with setose field in the median part, inner edge with additional thorn-like paired processes. Parameres well developed, simple apically. Tegminal strut longer than rest of tegmen, broad, simple at apex. Penis rod-like, slightly sinuate, with thorn-like projection at apex; penis capsule with arms weakly developed.

Female genitalia ( Fig. 3D ). Sclerite anterior to coxites in membrane connecting paraprocts absent. Coxites small, distinctly transverse, with inner edge pointed, ventral surface smooth. Styli visible, reduced. Bursa copulatrix without additional sclerite, simple, not divided, ending with common oviduct. Sperm duct short, originating at base, dorsally on bursa. Spermatheca lightly sclerotized, simple, vermiform, accessory gland small, membranous.

Distribution. Madagascar ( Fig. 7 ).

Type material examined. Holotype: “ Epilachna hovana Sic , typus (hand writing)/ Museum Paris, Madagascar, Baie d’Antongil, A. Mocquerys 1898” ( MNHN) ( Fig. 1D ) . Paratypes: same label data as the holotype (1: MNHN) ; same label data but 1897 (2: MNHN); S. de la baie d’Antongil (green card) (1: MNHN). Other material. MADAGASCAR: Ste Marie de Madagascar , Perrot Frères, X-XII 1896 (3 male: MNHN) ; Museum Paris , Madagascar, Valle de la Marimbona J. Descarpentries 1907 (1 fem: MNHN) ; Museum Paris , Madagascar, prov. de Fénerive, reg. de Soanierana, A. Mathiaux 1905 (1 male, 1 ex.: MNHN) ; Museum Paris , Madagascar prov. de Tamatave, A. Fauchère 1907 (1 ex.: MNHN) .

Remarks. Four male specimens (Fénerive, St Marie de Madagascar) were dissected and no differences in genitalia were observed.

Figures

FIGURE 1. Merma hovana (Sicard, 1907), non type (MNHN): A—habitus, frontal, B—habitus, lateral, C—habitus, dorsal, D—the holotype (MNHN) and its labels.

FIGURE 2. Merma hovana (Sicard, 1907), non type (MNHN): A—habitus, ventral, B—mouthparts, C—head, prosternum and mesoventrite, D—meso- and metaventrite, E—tarsal claws.

FIGURE 3. Merma hovana (Sicard, 1907), non type (MNHN):: A—penis, lateral, B—tegmen, lateral, C—penis inner, D—female genitalia, E—male genital segments IX and X, F—abdomen, male, G—tergite VIII, female, H—sternite VIII, female, I—tergite VIII, male, J—sternite VIII, male.

FIGURE 7. Distribution map of the Malagasy species of Merma Weise.