Balacra (Daphaenisca) affinis ( Rothschild, 1910 )

Durante, Antonio & Zangrilli, Maria Paola, 2016, Review of subgenus Daphaenisca Kiriakoff, 1953 (Lepidoptera: Erebidae: Arctiinae: Synthomini: Thyretina), with identification keys, and description of three new species, Zootaxa 4117 (2), pp. 151-171 : 163-164

Balacra (Daphaenisca) affinis ( Rothschild, 1910)

( Fig. 7 , 22 )

Pseudapiconoma affinis Rothschild, 1910 , Novitates zoologicae, XVII, 3: 442.

Balacra affinis ( Rothschild, 1910) ; Hampson 1914, Catalogue of the Lepidoptera Phalaenae , suppl. vol 1: 74.

Balacra (Balacrella) affinis ( Rothschild, 1910) ; Kiriakoff 1957, Bulletin et Annales de la Societe Entomologique de Belgique, 93, V–VI: 154–155.

Balacra (Daphaenisca) affinis ( Rothschild, 1910) ; Przybyłowicz 2009, Thyretini of Africa: 13.

Type locality. Democratic Republic of the Congo (Lectotype).

Distribution. Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Gabon, Uganda ( Przybyłowicz 2009).

Examined material. Lectotype ♂, Kassai district, Congo F. St., in coll. BMNH, examined (abdomen missing). Gabon: 1 ♂ Arct. g.sl. n. 5848 BMNH (Loango, West Africa), in coll. BMNH; 40 ♂, genitalia prep. n. 685 MAD, and 743 MAD, in coll. MSNS.

Uganda: 1 ♂ Arct. g.sl. n. 5849 BMNH, in coll. BMNH.

Democratic Republic of the Congo: 1 ♂ Arct. g.sl. n. 5850 BMNH, in coll. BMNH; 3 ♂, genitalia prep. n. 5, 6 and 7 MSNS-RMCA. in coll. RMCA.

Diagnosis. Very similar to inexpectata sp. n. and daphaena , from which it is distinguishable with certainty with reference to the shape of the uncus, bifurcate in inexpectata sp. n. and daphaena , and trifurcate in affinis . Female genitalia differs in the rib-like rows on the surface of the corpus bursae, whereas it is smooth both in inexpectata sp. n. and daphaena .

Two yellow marks on the third and fourth abdominal tergites, as well as the serrate antennae and the yellow patagia on the thorax, clearly distinguish this species from magnoloi sp. n. The shape and colour of the hindwings (grey-brown) are distinct from those of flava sp. n. (yellow) and magnoloi (roughly circular with ground colour darker and red dots or small bands in the middle).

Habitus. ♂. Forewing length from 14 to 17 mm (n=46); upperside ground colour dark grey-brown with large suffusion of red scales mainly in spaces between veins. Presence of thin, often incomplete subcostal red line, and one well-marked red dot at the wing base on the inner margin. Underside same ground colour as upperside, fading towards the base and red suffusion generally sparser.

Hindwings slightly elongated with upperside ground colour lighter than forewings, darkening towards the margins. Underside same ground colour as upperside, with sparse red scales.

Fringes same colour as wings.

Frontoclypeus grey-brown with red lateral margin; vertex yellow bordered by red. Labial palpi dorsally and ventrally reddish with yellow tips. Eyes bordered by red; antennae yellow with red scales around scapus, serrate.

Thorax same ground colour as wings, with four red marks on mesoscutum, one central yellow mark on mesoscutellum, two more red lateral marks on metathorax; patagia yellow; tegulae grey-brown with small red dot anteriorly at junction with costal margin of forewings. Thorax underside grey-brown.

Legs with red femurs, yellow tibiae and tarsi, brown praetarsi. Spurs formula: 0-2-2.

Abdomen same ground colour as wings, with two falcate red marks on tergum A1, often joined to form a “U”. One yellow mark on both A2 and A3; starting from the second urite, tergites completely covered by red scales under typically grey-brown layer, red scales emerging only at caudal edge of tergites, surrounding them. This character differs from daphaena (see description) and was observed in a series of 46 affinis abdomens, and is therefore a probable diagnostic character.

A8 tergite not completely red (as in daphaena ); presence of variable yellow-red colouration, with cephalic half dark grey-brown.

Presence of pleural tuft on every segment.

Underside of abdomen reddish fading to yellow.

Anal tuft yellow, sometimes with predominance of red scales (the colour of the anal tuft could be of diagnostic relevance).

Genitalia. ♂. A8 tergum roughly triangular in dorsal view, almost twice as long as A7. Uncus tower-shaped, with three apical processes, of which lateral two pointed and central one flattened and bent backwards; in dorsal view extending inside tegumen with U-shaped concavity, whose arms could be considered socii ( Fig. 22 C, 22D).

Tegumen in dorsal view large, roughly arc-shaped ( Fig. 22 D); tegumen-vinculum complex slender; saccus narrow and tapered; juxta roughly square with dome-like swelling in middle, dorsally connected to ring-like sclerotisation of the anellus. Transtilla composed of two arms clearly separated in middle and laterally linked to valvae. Tuba analis with slerotised large scaphium, membranous in middle, saddle-shaped ( Fig. 22 A). Valvae roughly triangular with short costal distal process and large sacculus ( Fig. 22 A). Aedeagus tubular with short coecum; vesica with main lobe bearing cluster of slender spines and conical distal lobe ending in small cornutus ( Fig. 22 B).

♀. Not examined due to lack of materials.

Figures

FIGURE 22. Genitalia of Balacra affinis. ♂ Gabon, Makokou-Ipassa, 500 m, 0 ° 30 ’ 42 ” N 12 ° 48 ’ 13 ” E, 5 / 10 - 4 - 2010, Durante leg., gen. prep. n. 685 MAD. A) tegumen-vinculum complex in ventral view; B) aedeagus; C) tegumen and uncus in lateral view; D) same in dorsal view. Arrows indicate junction of uncus and tegumen. co, cornuti; cp, costal process; sa, saccus; sc, scaphium; sl, sacculus; so, socius; te, tegumen; uc, uncus; us, U-shaped concavity; va, valva.

FIGURES 5 – 7. Adults of Balacra (Daphaenisca) sp. Fig. 5. Male of Balacra daphaena: upperside (left) and underside (right). Fig. 6. Female of Balacra daphaena: upperside (left) and underside (right). Fig. 7. Male of Balacra affinis: upperside (left) and underside (right).