Ivalia korakundah Prathapan, Konstantinov and Duckett

Duckett, Catherine N., Prathapan, K. D. & Konstantinov, Alexander S., 2006, Notes on identity, new synonymy and larva of Ivalia Jacoby (Coleoptera: Chrysomelidae) with description of a new species, Zootaxa 1363, pp. 49-68 : 55-60

Ivalia korakundah Prathapan, Konstantinov and Duckett , new species

( Figs 1 , 3–8 )

Description of adult. Size moderate, length (excluding head) 1.8 to 2.0 mm, width 1.0 to 1.2 mm, oblong, narrowed between elytra and prothorax, elytra ovate. Color lemon yellow; fourth antennomere onwards piceous, last antennomere lighter than preceding one. Labrum and clypeus brownish. Eye black to crystal white, surrounded by dark brown ring that extends to gena, distinct only in specimens with lighter eyes. Pronotum with black medial longitudinal stripe hardly reaching anterior or posterior margin, narrowed at both ends, widest in anterior 1/3, margins indistinct as color gradually lightens and merges with surrounding yellow. Pronotal stripe variable in size and prominence. Each elytron with broad black stripe narrowing to either end, widest at anterior 1/3 followed by a transverse, deep emargination from middle of lateral side. In some specimens it almost divides elytral stripe into two. Lateral sides and margins of thoracic sternites tend to be dark brown, coxae light yellow. First three abdominal sternites concolorous with thoracic sternites.

Head ( Figs 1 , 2 A–B) hypognathous. Frons and vertex form slightly convex line in lateral view. Vertex with shallow, minute, moderate sized punctures. Supraorbital pore circular, not surrounded by shallow grooves or tiny setiferous punctures, bearing an upcurved seta slightly shorter than second antennomere. Antennal callus 1.5 times wider than long, length slightly exceeding diameter of antennal socket, slightly raised, anterior end almost obtusely angulate, entering into interantennal space. Midcranial suture absent. Supracallinal sulcus shallow, poorly developed. Suprafrontal sulcus weak but distinct. Midfrontal sulcus short, deep. Supraantennal sulcus narrow, stronger than suprafrontal sulcus. Supraorbital sulcus short, shallow, ill defined. Orbital sulcus distinct. Subgenal suture narrow, distinct. Orbit narrow, subequal to transverse diameter of antennal socket. Interantennal space about twice as wide as diameter of a socket, subequal to transverse diameter of eye. Frontal ridge short, wide, slightly convex; anterofrontal ridge broad, as high as frontal ridge, laterally as high as medially, anteriorly flat above clypeus with concave anterior margin ( Fig. 3 A). Frontal ridge and anterofrontal ridge together appear as flattened equilateral triangle, merging above clypeus. Lateral margin of frons with two closely placed rows of setae merging below antennal socket: mesal row with long and lateral row with short setae. Frontoclypeal suture with a row of long setae. Labrum ( Figs 3 A–B) with six setiferous pores arranged in a curved, transverse row; distance between middle four pores less than that between lateral pore and adjacent one. Margin of incision on labrum with short setae.

Maxillary palp ( Fig. 3 B) exceeds basal two antennomeres in length; basal palpomere tiny, not longer than wide; second club-shaped, subequal to, or slightly longer than third; third club- shaped, thicker than second, widening towards apex; fourth thin, a little longer than half of third.

Antennae hardly reach middle of elytron. First antennomere club-shaped; second thicker than third, slightly thinner than first, slightly longer than half of first; fourth slightly longer than second but shorter than third; fifth onwards antennomeres thickened; fifth subequal to third in length; fourth and sixth subequal in length; seventh slightly longer, much thicker than sixth; seventh subequal to eighth; ninth and tenth separately slightly shorter than eighth; tenth 1.4 times longer than wide; eleventh shorter than two times length of tenth.

Pronotum 1.4 times wider than long, anteriorly wider than posteriorly, convex. Lateral margin weakly curved, anteriorly wider than posteriorly. Anterolateral callosity well developed, convex, as long as 1/3 of lateral margin including anterolateral callosity, anteriorly higher than posteriorly, seta-bearing pore situated on dorsal posterior face of callosity forming indistinct denticle at pore, diameter of pore exceeding width of lateral margin; posterior callosity protruding, about 1/3 as long as anterolateral callosity; seta on anterolateral callosity as long as lateral margin; seta on posterolateral callosity slightly longer than half of seta on anterolateral callosity. Anterior margin straight, posterior margin gently curved; disc with small punctures with extremely minute seta arising from each puncture visible at high magnification; minute as well as medium sized scattered punctures also present.

Intercoxal prosternal process ( Fig. 3 B) narrow in middle, apically widened with rounded apex, projecting much beyond coxa. Length of intercoxal prosternal process from anterior margin of sternite to posterior end 3.6 times distance between anterior margin of prosternum to coxal cavity; width of intercoxal prosternal process at middle less than distance between anterior margin of prosternum to coxal cavity. Width of mesosternal intercoxal process subequal to half of distance between anterior margin of mesosternum to posterior end of intercoxal process (cf. Fig. 3 C). Distance between anterior margin of mesosternum to mesocoxal cavity slightly less than width of mesosternal intercoxal process. Prosternum slightly longer than metasternum; mesosternum shorter than metasternum. Intercoxal prosternal process with a vertically elevated ridge along middle, ridge being indistinct in proximal half, pronounced beyond middle with longitudinal depressions on either side of ridge. Mesosternum with indications of a horse-shoe shaped raised process on top, but poorly developed in most specimens ( Fig. 5 A). Metasternum with a circular depression with well-defined, ring-like ridge surrounding it ( Fig. 5 A).

Elytron without humeral callus, with maximum width at proximal 1/3, tapering to apex ( Figs 1 , 3 D). Elytral apex apparently concave, forming acute angle with sutural margin. Lateral margin of elytron delimiting epipleuron dorsolaterally, reaches up to sutural margin; visible from above except in distal 1/4. Elytral punctures stronger than those on pronotum; interstices flat with small minute punctures, distance between punctures up to diameter of three punctures in middle of disc. Elytral punctures with minute seta visible under high power. Internal surface ( Fig. 3 D) uniformly invested with small granulations. Elytral binding patches absent. Mesoscutellum triangular, broader than long, impunctate. Pro- and mesotibiae without apical spine. Width of pro- and mesofemora subequal to maximum width of epipleuron. Profemur slightly shorter than protibia, ventral side nearly flat, dorsally convex. Foretibia rounded in cross section, slender, proximally half as thick as distally. First protarsomere in male not distinctly wider than in female, ventrally flat, with short, pointed setae, long setae absent. Second protarsomere narrower than first; third longer than second, shorter than first, deeply bilobed; fourth slightly shorter than two times length of third, ventral side of third tarsomere with long capitate setae. Mesofemur slightly longer than mesotibia. Metafemur about two times longer than wide ( Figs 1 , 3 C), posteriorly with a dorsal groove and a ventral ridge for reception of tibia. Metatibia slightly longer than metafemur. Metatibia curved in lateral view. Dorsal surface convex with flat apex; mesal margin of dorsal surface with a short row of sharp bristles at distal end; lateral margin with sharp, long spinules from distal end to middle or slightly beyond. Metatibia about 3.4 – 3.7 times longer than first metatarsomere. Metatibial spur 1.3 times longer than tarsal claw ( Figs 3 E–F). Third metatarsomere bearing specialized spatulate setae ventrally ( Figs 3 F–G). Claw long, narrow with a short appendix ( Fig. 3 F). Intercoxal process of first abdominal ventrite with oval depression in middle, bearing ridge on either side those join together anteriorly with acute process between metacoxae. Abdomen with five visible ventrites. Length of first abdominal ventrite along middle slightly more than length of next three ventrites combined; fifth ventrite longer than fourth but shorter than fourth and third combined ( Fig. 4 D). Last visible abdominal tergite of female nearly as wide as long, with a shallow groove along middle ( Fig. 4 C).

Female genitalia with receptacle of spermatheca ( Fig. 4 A) cylindrical, about four times longer than wide, widest in middle, slightly narrowed towards either end; pump curved, vertical part very short, horizontal part about half as long as receptacle, without denticle at apex; duct originate away from receptacle, curved towards receptacle, hardly reaching middle of receptacle. Vaginal palpi ( Fig. 4 E) lightly sclerotized, proximally fused like a horse shoe, narrowed from proximal end to distal end, lateral and mesal margins hardly form acute angle, setae not longer than maximum width of a palpus, placed near apex and lateral margin; tignum ( Fig. 4 B) curved with a central canal, distal sclerotization broad, spoon shaped, without setae, proximal sclerotization laterally flattened, broad, but narrower than distal sclerotization.

Aedeagus ( Figs 5 B–C) in ventral view proximally wider than distally, highly convex along ventral side with flat, raised, rounded apex; in lateral view, moderately curved, widest near middle with acute, strongly recurved apex. Tegmen Y-shaped.

Remarks. This species can be distinguished from the two described species of south Indian Ivalia by the following characteristics, including coloration and tibial spinules. Ivalia obrieni (Gruev and Askevold) has a transverse dark basal band on the pronotum ( I. korakundah has a black medial longitudinal stripe on pronotum) and black elytron with lateral yellow band ( I. korakundah has a black band along middle of elytron, the band being transversely emarginated in middle). Ivalia indica (Gruev and Askevold) is entirely yellow brown without black stripes. Head of I. indica has four deep punctures arranged in a transverse row near posterior margin of antennal calli. Such punctures are absent in the other two species. Elytral punctures are also much stronger in I. indica than in other south Indian species. On the lateral edge of the dorsal surface of the metatibia, I. obrieni has 3–4 spines while I. korakundah has a row of more than ten spinules.

Adults and larvae of Ivalia korakundah were collected at Korakundah Estate in south India, by sifting moss from the trunk of large pine trees. At Doddabetta Valley, adults were collected by sifting the moss Isopterygium sp. ( Hypnaceae ) growing on rock. Females of a closely related alate yellow species that is widely distributed throughout south India (called here Ivalia sp. 1) in which the thoracic maculation is absent and the elytral stripe is not transversely emarginate were also collected at Korakundah Estate. The elytral stripe is reduced to a circular spot or absent in specimens from Kerala and Karnataka. The scutellum in I. korakundah is triangular, much wider than long, and brown in color while in the other species it is rounded and black. The alate Ivalia sp. 1 has a well developed humeral callus and a longer metathoracic sternite. Structure of its female genitalia is also different. Receptacle of the spermatheca is much broader in the alate Ivalia sp. 1 compared to that of I. korakundah .

Type material. Holotype ɗ. Labels: 1) South India Western Ghats Tamil Nadu, Nilgiri, env. Ooti, Korakundah Tea estate 25.XI.2003 2300m, N11.14 '44" E76.33 '31", leg. Konstantinov, Prathapan, Saluk; 2) Holotype Ivalia korakundah sp. nov. des. Prathapan, Konstantinov, Duckett ( USNM). Paratypes 30 specimens: the same labels as holotype (25 USNM, 3 PKDC, 2 BMNH). Two specimens: South India Western Ghats Tamil Nadu, Doddabetta, 22.VI.2004 2600m, N11°23'59" E76°44'06" Prathapan K. D. Coll. ( PKDC). Four specimens: South India Western Ghats Tamil Nadu, Doddabetta Valley, 24.VI.2004 Prathapan K. D. Coll. ( PKDC).

Etymology. The specific epithet refers to the Korakundah Tea Estate of the Nilgiris where the holotype was collected; it is a noun in apposition.

Figures

FIGURE 1. Dorsal habitus of Ivalia korakundah new species, total body length 1.8 mm.

FIGURE 2. Ivalia species. A-D I. viridipennis, A, dorsal habitus, B, lateral habitus, C, anterior view of head, D, metathoracic leg; E, I. bella, frontal view of head; F, I. dorsalis, holotype, lateral habitus.

FIGURE 3. Ivalia korakundah, adult. A, frontal view of head; B, ventral view of head and pronotum; C- G, Qiagen ™ cleared material; C, dorsal view of pterothorax and abdomen, note tracheoles and metendosternite; D, interior view of elytron showing regular granulations; E, metatibial spur; F, ventral view of metatarsi; G, tarsal setae of third tarsomere, total width of image 25 microns.

FIGURE 4. Ivalia korakundah, female. A, spermatheca; B, tignum (eighth sternite); C, apical abdominal tergites; D, ventral view of abdomen; E, vaginal palpi.

FIGURE 5. Ivalia korakundah. A, ventral view of meso- and metathorax; B, ventral view of aedeagus; C, lateral view of aedeagus.

FIGURE 6. Ivalia korakundah, 3 rd instar larva. A, left lateral habitus light microscopy, note melanized tubercles; B, ventral habitus, SEM coated material; C, right lateral habitus, coated material, note lack of cuticular variation between sclerotized and unsclerotized integument.

FIGURE 7. Ivalia korakundah, larva. A, ventral view of head capsule, (antennae damaged from critical point drying); B, antenna with intact antennal papilla; C, anterior view of head; D, dorsal view of vertex showing minute peg-like sensilla; E, detail of sensillum of the vertex; F, detail of depressed sensillum of the labium; G, apical segment of labial palp, note long basiconic sensillum and depressed sensillum on exterior lateral face; H, right maxillary palp and labium, ventral view.

FIGURE 8. Larvae of Ivalia korakundah. A, dorsal view of first instar larva; B, lateral view of first instar larva (area between abdominal segments 4 and 5 damaged from critical point drying); C, lateral view of abdominal apex of third instar larva; D, ventral view of abdominal segments 2 and 3 of third instar larva; E, ventral view of first instar larva showing prothoracic and mesothoracic legs, note pillow-like pulvillus.