Balacra (Daphaenisca) inexpectata Durante & Zangrilli

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 : 164-167

Balacra (Daphaenisca) inexpectata Durante & Zangrilli sp. n.

( Figs. 16, 17 , 23, 24)

Holotype. ♂ Gabon, Ipassa-Makokou; 0°30’43’’N, 12°48’13’’E; 500 m 19-2/ 11-3-2011, Durante legit. Genitalia prep. n. 754 MAD. In coll. MSNS.

Paratype. 1 ♀, Gabon, Ipassa - Makokou, m 500, 4/ 13-12-2013, Durante & Gallizia leg. Genitalia prep. n. 742 MAD. In coll. MSNS.

Distribution. North-East Gabon (only the type locality).

Diagnosis. Very similar to affinis and daphaena , from which it is distinguishable with certainty with reference to the shape of the uncus, which is trifurcate in affinis and has a different bifurcation in daphaena . Also clearly diagnostic for the latter are the shape of the valva and the single big cornutus of the aedeagus in daphaena as opposed to the cluster of spines in inexpectata sp. n.

Corpus bursae in affinis presents several rib-like rows; it has a smooth appearance both in daphaena and inexpectata sp. n., but the latter has only one signum, whereas daphaena has got two.

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 diagnostic with respect to flava sp. n. (yellow) and magnoloi (roughly circular with ground colour darker and red dots or small bands in the middle).

FIGURE 23. Genitalia of Balacra inexpectata sp. n. ♂ Gabon, Makokou-Ipassa, 500 m, 0°30’42”N 12°48’13”E, 19-2/ 11-3- 2011, Durante leg., gen. prep. n. 754 MAD. A) tegumen-vinculum complex in ventral view; B) aedeagus; C) cluster of cornuti enlarged; D) single cornutus enlarged; E) tegumen and uncus in lateral view; F) same in dorsal view. Arrows indicate junction of uncus and tegumen. co, cornuti; cp, costal process; ju, juxta; sa, saccus; sc, scaphium; sl, sacculus; so, socius; te, tegumen; uc, uncus; us, U-shaped concavity; va, valva.

Habitus. ♂ and ♀. Forewing length: male 16 mm, female 21 mm; upperside ground colour dark grey-brown with large suffusion of red scales mainly in spaces between veins. Presence of thin subcostal red line, and one wellmarked red dot at wing base on inner margin. Underside same ground colour as upperside with sparser red suffusion, almost absent towards the apex.

Hindwings slightly elongated (especially in the female) with upperside ground colour as in forewings, and very sparse red suffusion at base. Underside same ground colour as upperside, with sparse red scales, denser at wing base. Fringes same colour as wings.

Frontoclypeus dark grey-brown with red lateral margin; vertex yellow.

Labial palpi dorsally and ventrally reddish with yellow tips.

Eyes bordered by red; antennae yellow with red scales around scapus, smoothly serrate, thinner in the female.

Thorax same ground colour as wings, with four red marks on mesoscutum and 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 forewing. Thorax underside grey-brown.

Legs with red femurs (in the female only dorsally and externally, grey-brown internally), tibiae and tarsi yellow, praetarsi brown. Spurs formula: 0-2-2.

Abdomen same ground colour as wings, with two falcate red marks on tergum A1, and small orange dot between them. One yellow mark on both A2 and A3; five red transversal bands at caudal margin of segments from second to sixth, interrupted dorsally.

A8 tergite red with many yellow scales caudally; in the female, completely yellow with small anterior red patches.

Presence of pleural tuft on every segment.

Underside of abdomen as upperside, red margins discontinuous.

Anal tuft in the male yellow, in the female yellow (dorsal) and red (ventral).

Genitalia. ♂. A8 tergum roughly triangular in dorsal view, almost twice as long as A7. Uncus Y-shaped in dorsal view, with basal stem quite long and stout, extending inside tegumen with U-shaped concavity (Fig. 23E, 23F), whose arms are considered socii. Tegumen quite strong; vinculum slender; saccus narrow, juxta roughly square with dome-like swelling in middle, dorsally connected with ring-like sclerotisation of the Anellus (Fig. 23A). Transtilla composed of two arms clearly separated in middle and laterally linked to valvae. Tuba analis with slerotised large scaphium, saddle-shaped (Fig. 23A).

Valvae roughly triangular with S-shaped costa and costal distal process (slightly longer than in affinis ); large sacculus (Fig. 23A).

Aedeagus tubular with short coecum (Fig. 23B); vesica with main lobe bearing cluster of long slender spines (Fig. 23C) and conical distal lobe ending in small cornutus (Fig. 23D).

♀. Seventh tergum 50% longer than sixth segment; seventh sternum slightly less than 50% longer than sixth. A8 about one third shorter than sixth segment. Anterior and posterior apophyses short, anterior ones half length of posterior ones, the latter about half length of papillae anales. Dorsal pheromone glands paired, bag-like, similar length to posterior apophyses ( Fig. 24 C). Ventral pheromone glands paired, bag-like, slightly more elongated than dorsal glands ( Fig. 24 D).

Ostium bursae roughly circular well sclerotised. Antrum membranous and short, narrower than ostium; ductus bursae membranous, long, S-shaped, with one side of the caudal portion well sclerotised ( Fig. 24 A). Ductus seminalis emerging at end of ductus bursae on right side. Corpus bursae spherical, membranous, with single long signum ( Fig. 24 B).

Derivatio nominis. The species is called inexpectata from the Latin “inexpectatus”, meaning “not expected”, because of its unexpected discovery during dissection work on affinis .

Figures

FIGURE 24. Genitalia of Balacra inexpectata sp. n. ♀ Gabon, Makokou-Ipassa, 500 m, 0 ° 30 ’ 42 ” N 12 ° 48 ’ 13 ” E, 4 / 13 - 12 - 2013, Durante leg., gen. prep. n. 742 MAD. A) genitalia in dorsal view; B) Signum enlarged (arrow showing correspondence); C) dorsal pheromone glands; D) ventral pheromone glands. an, antrum; cb, corpus bursae; db, ductus bursae; dg, dorsal pheromone glands; os, ostium bursae; si, signum; vg, ventral pheromone glands.

FIGURES 16 – 19. Adults of Balacra (Daphaenisca) sp. Fig. 16. Holotype male of Balacra inexpectata sp. n.: upperside (left) and underside (right). Fig. 17. Paratype female of Balacra inexpectata sp. n.: upperside (left) and underside (right). Fig. 18. Paratype male of Balacra magnoloi sp. n.: upperside (left) and underside (right). Fig. 19. Holotype female of Balacra flava sp. n.: upperside (left) and underside (right).