Scymnus (Scymnus) arciformis Chen, Wang, and Ren, 2013

Reddy, B. Thirupam, Chandran, Nithya, Kumar, Ashwani & Sathyanarayana, K., 2023, Scymnus (Scymnus) arciformis Chen, Wang, and Ren (Coleoptera: Coccinellidae), a New Record for India, The Coleopterists Bulletin 77 (1), pp. 140-145 : 140-144

Scymnus (Scymnus) arciformis Chen, Wang, and Ren, 2013

( Figs. 1–3 )

Scymnus (Scymnus) arciformis Chen et al. 2013: 445 .

A detailed description of external morphology and male genitalia was given by Chen et al. (2013); however, it lacks the description of terminal abdominal

142 segments, female genitalia, and measurements and (Scymnus) apiciflavus (Motschulsky, 1858) morratios of male genitalia. We provide a supplemen- phologically. However, S. arciformis can be differtary description below. entiated from the latter by the elytra black with

Out of eight Indian species reported earlier, apical one-third yellowish brown; and the penis, S. (S.) arciformis most closely resembles Scymnus particularly the inner margin of the distal one-third, expanded into an undulate membranous structure, with the area beyond membranous region tapering to asymmetrical folds ending in a ribbon-like membrane structure which is lacking in S. apiciflavus .

Supplementary Description.Antenna ( Fig. 1C ): Outer lateral margin of antennomeres 1–3 with few long setae, lateral sides of antennomeres 7–11 covered with long hairs, surface and apex of terminal antennomere with intermixed short and long setae. Antennomere 2, 0.3 times as long as scape; antennomere 3, 0.6 times as long as scape, narrower than scape and antennomere 2 together; antennomeres 4–6 sub-rectangular, small; antennomeres 7–8 nearly trapezoidal. Labrum ( Fig. 1D ): Nearly trapezoidal, 2.2 times as wide as long; outer margin membranous; basal margin arcuate, apical margin 144 nearly truncated; sclerotized region punctate and covered with long, distinct, sparse setae. Mandible

( Fig. 1E ): Sclerotized, 1.3 times as long as wide,

widest below molar tooth, molar tooth conical,

slightly curved; abruptly tapering from distal onethird, ending in bifid tooth. Maxilla ( Fig. 1F ):

Surface covered with long and short setae; terminal palpomere 1.6 times as long as wide, lacinia and galea both with short, brush-like hairs at apex.

Labium ( Fig. 1G ): Prementum nearly trapezoidal with lateral sides angled, apical angle distinctly pro-

jected; ligula membranous, sub-rectangular, surface punctate and covered with dense, minute setae.

Terminal abdominal segments: Males and females show external sexual dimorphism, with ventrite 5

truncate in male ( Fig. 2A ) and rounded in female

( Fig. 3A ).

Male abdomen: Abdominal tergite VIII ( Fig. 2B )

about 2.4 times as wide as long, widest slightly below basal margin, surface finely punctate and covered with short setae, apical and lateral margin fringed with medium-sized setae, basal margin deeply arcuate as compared to female, lateral margin rounded,

apical margin nearly truncate medially; sternite VIII

( Fig. 2C ) about 10.5 times as wide as long, widest at base, apical and lateral margin fringed with sparser setae of intermixed sizes, apical margin shallowly emarginate medially; segments IX and X ( Fig. 2D )

closely articulated, apodeme of sternum IX rod-like;

tergite X with arcuate apical margin fringed with long setae medially. Male genitalia: Penis ( Fig.2E ) 0.7 mm

Fig. 4. Map of India showing collection locality for long, sclerotized, C-shaped tube-like structure with Scymnus arciformis .

capsule at proximal end with two lateral arms, an outer arm (0.08 mm long, 0.06 mm wide) and inner arm (0.06 mm long, 0.03 mm wide), base of capsule spicule with distinct rounded base present on bursa slightly depressed towards inner extension, apex of copulatrix ( Fig. 3E ).

penis extended into tubular structure, distal one-third Specimens Examined. INDIA: Jharkhand: of inner margin expanded into undulate membranous Saraikela: Kharswan, Paramadih , Basic Seed structure, area beyond membranous region tapering Multiplication and Training Centre , Central Silk to asymmetrical folds ending in ribbon-like membra- Board (Fig. 4), 24 ♂♂, 20 ♀♀, BSMTC, hand colnous structure ( Fig. 2F ). Tegmen ( Figs. 2G, H ) with lection using fine brush from mango leaves infested parameres oblong, about 6 times as long as wide, with leafhoppers, 15.IV.2022, 22.78981833°N , surface densely punctate with minute setae; tegminal 85.80752333°E, coll. B. Thirupam Reddy.

strut rod-like, 0.14 mm long with rounded apex and Distribution. China (Yunnan, Hainan), India base widely forked; penis guide 1.3 times as long as (Jharkhand). New record for India.

wide. Female abdomen: Abdominal tergite VIII

( Fig. 3B ) about 2.1 times as wide as long, widest slightly below basal margin, surface punctate, cov- ACKNOWLEDGMENTS

ered with small setae, basal margin shallowly arcuate, apical and lateral margin covered by sparser setae We thank Dr. Poorani Janakiraman, Division of of intermixed sizes, apical margin broadly rounded; Crop Protection, ICAR-National Research Centre for sternite VIII ( Fig. 3C ) about 4.6 times as wide as Banana, Trichy, India for identification of Scymnus long, apical margin broadly rounded, apical and lat- and for sharing literature. We are also thankful to eral margin covered by sparser setae of intermixed Central Silk Board for providing necessary support sizes. Female genitalia ( Figs. 3D, E ): Coxites sub- to document these observations. The correspondtriangular and apical surface covered with long setae; ing author is thankful to the Head, Division of spermatheca C-shaped with one end bulged, surface Entomology, the Director, Indian Agriculture covered by concentric rings; sclerotized thorn-like Research Institute (ICAR), New Delhi and Science and Engineering Research Board (SERB), Department of Science and Technology (DST), Government of India (Project code: CRG/2021/002565) for the funding to carry out the research work.

Figures

Fig. 1. Scymnus arciformis, female. A–B) Dorsal and lateral habitus, C) Antenna, D) Labrum, E) Mandible, F) Maxilla, G) Labium.

Fig. 2. Scymnus arciformis, male. A) Abdomen, ventral, B) Abdominal tergite VIII, C) Abdominal sternite VIII, D) Abdominal segments IX and X, E) Penis, F) Apex of penis, G–H) Tegmen, ventral and lateral.

Fig. 3. Scymnus arciformis, female. A) Abdomen, ventral, B) Abdominal tergite VIII, C) Abdominal sternite VIII, D) Genitalia, ventral, E) Spermatheca with sclerotized spicule on bursa copulatrix.