Megymenum distanti, Kocorek, Anna & Ghate, Hemant, 2012

Kocorek, Anna & Ghate, Hemant, 2012, Megymenum distanti, a new remarkable species of the Dinidoridae subfamily Megymeninae (Hemiptera: Heteroptera: Dinidoridae) from India, Zootaxa 3218, pp. 31-39 : 31-35

Megymenum distanti , new species

( Figs. 1–9)

Diagnosis. The new species is similar to M. affine BOISDUVAL and M. brevicorne (FABRICIUS) in its body outline and sculpture; nevertheless, it can easily be separated from both of these species by the characters given in the Table 1 .

Description. Body dark brown with metallic tinge and light brown membrane, elongate, abdomen slightly broader than pronotum ( Fig. 1).

Head punctured; paraclypei deeply concave and much longer than clypeus; preocular part swollen with small sharp process in female; eyes rounded, protruding and pedunculate, light-brown, ocelli of the same color, interocellar distance 1,8–2,1; antennae 4-segmented, 1st segment short, not reaching apex of head, 2nd long and broad, 3rd flattened and broadened, 4th spindle-shaped; rostrum same color as rest of body, reaching mid-coxae, its 1st segment extending beyond base of head, bucculae lobed, buccular surface convex and rugose, almost of the same color as head.

Pronotum generally of same color as head, with numerous fine ridges, and punctures on anterior border which is drawn forwards to form a small collar-like structure behind base of head, bearing small but sharp spines in female; antero-lateral margins rounded without processes, antero-median tuberosity large and conspicuous; lateral pronotal margins irregularly rugged with a single pointed projection; posterior pronotal angles broadly rounded; posterior pronotal margin straight at base of scutellum.

tanti new species.

Meso- and metasternum with a deep median groove; scent gland spout large and conspicuous, evaporatoria wrinkled.

Scutellum with punctures dispersed over its entire surface; prominent cavity-like depressions at basal angles.

Corium shorter than scutellum, membrane shorter than abdomen, cream-colored, with brownish patches. Legs uniformly colored, under-surface of femora with ten small spines (more or less distinct) arranged in two rows with distal spines progressively robust or strong, hind tibia of female slightly dilated.

Abdominal sterna of same color as remaining parts of body, sparsely punctured; lateral parts of sterna uncovered by hemelytra, well conspicuous; each sternum laterally with small posteriorly directed apical projection and very small median lobe.

Male genital capsule with median swollen process on its ventral rim; paramere with small and triangular growth; anterior part of ejaculatory reservoir strongly coiled.

Female 9th paratergite similar to that of M. affine and M. brevicorne , 1st valvifers with distinct median elevation. Spermathecal bulb small, pumping region well defined, distal and proximal flanges distinct, spermathecal duct membranous, forming folding sack-like structure with minute spines, ring sclerite present.

Measurements (in mm). Male: total body length 13.0; abdominal width 7.1; head length 2.3; head width 2.5; interocelar distance 1.8; antennal segments: I 0.7, II 1.6, III 1.3, IV 1.1; pronotal length 3.8; pronotal width 6.4; scutellum length 3.6; width 3.5.

Female: total body length 13.9; abdominal width 8.9; head length 2.4; head width 2.7; interocelar distance 2.1; antennal segments: I 0.8, II 1.7, III 1.4, IV 1.1; pronotal length 4.0; pronotal width 7.0; scutellum length 3.9; width 3.9.

Type material. Holotype male: India, Pune, August 2010, coll. H.V. Ghate & Sanket Tembe, preserved in the collection of University of Opole at Department of Biosystematics; Paratype female: India, Pune, August 2010, coll. H.V. Ghate & Sanket Tembe, preserved in the collection of Modern College, Pune; an additional pair of male and female paratypes, coll H.V. Ghate (September 2010, same locality), also preserved in the collection of Modern College.

Etymology. The species name is dedicated to W.L. Distant, the eminent British entomologist and the author of the Hemiptera volumes in the monumental Fauna of British India series, as well as for many other papers on Hemiptera .

Notes on biology. The new species was collected from Pune in August-September 2010 as adults ( Fig. 2) and as instars ( Fig. 3) on the host plant Diplocyclos palmatus (Cucurbitaceae) ( Fig. 4). This climber grows at several places along the roadside on the campus of the University of Pune. The adults as well as nymphs were found to feed exclusively on tender shoots. Mating pairs as well as all stages of nymphs also fed on the same plant, and not on other plants that grow profusely near the side of its host plant. Neither nymphs nor adults smell strongly or release copious secretions when handled.

Tables

TABLE 1. Comparative account of some important distinguishing characters of M. affine, M. brevicorne and Megymenum dis-

Characters	M. distanti , new species	M. affine	M. brevicorne
Head dorsal surface	clearly concave (fig. 5)	almost flat (fig. 10)	clearly concave (fig. 15)
Preocular part of head	swollen with very small sharp process (fig. 5)	flat with sharp process (fig. 10)	very swollen without process
Interocelar distance	1.8–2.1	1.8–1.9	1.45–1.55
Third antennal segment	flat and broad	flat and only slightly broad- ened	flat and only slightly broadened
Apex of the 4th antennal segment	of the same color as its remaining part	clearly lighter than its remaining part	clearly lighter than its remaining part
Pronotum	anterior median tuberosity swollen, lateral pronotal mar- gins irregularly rugged with pointed projection (fig. 6)	anterior median tuberosity flat and almost invisible, lateral pronotal margins smooth with rounded projection (fig. 11)	anterior median tuberosity strongly swollen, lateral pronotal margins irregularly rugged with obtuse projection (fig. 16)
Lateral margins of sterna	with small posterior apical projection and very small median lobe, yellow spot absent (fig. 7)	with a single pyramid-shaped apical projection bearing yellow spot, and a small median lobe (fig. 12)	with a single pyramid-shaped apical projection bearing yellow spot, and a small median lobe (fig. 17)
Paramere	rounded, bearing small hypo- physis with shallow incision (fig. 9)	oval with elongate hypophy- sis (fig. 13)	elongate with sharp and prolonged hypophysis (fig. 18)
Anterior part of ejaculatory reservoir	strongly coiled (fig. 8)	strongly coiled (fig. 14)	straight (fig.19)