Crinibracon chromusae Gupta & van Achterberg

Gupta, Ankita, Achterberg, Cornelis Van & Chitrala, Malathi, 2016, A new species of Crinibracon Quicke (Hymenoptera: Braconidae) parasitic on pupae of Hasora chromus (Cramer) (Lepidoptera: Hesperiidae) from India, Zootaxa 4158 (2), pp. 281-291 : 282-290

Crinibracon chromusae Gupta & van Achterberg sp. n.

( Figs 1 & 2 )

Holotype, length of body 3.4 mm, fore wing 3.0 mm, ovipositor 0.67 mm, setose part of ovipositor sheath 0.16 mm. Paratypes, length of body 3.24–3.70 mm, fore wing 2.99–3.02 mm, ovipositor 0.62–0.67 mm; setose part of ovipositor sheath 0.16–0.22 mm. The comparative details are provided in Table I.

Diagnosis. Crinibracon chromusae sp. n. ( Figs 1−2 ) resembles C. sinicus ( Yang, Chen & Liu, 2008) ( Fig. 3 ) in general appearance, however, differs from the latter in the following set of characters: (i) the colour pattern, especially the sides of the central patch of T2 curved (vs nearly straight); (ii) length of setose part of ovipositor sheath 0.05–0.07× fore wing length (vs 0.08×); (iii) length of first tergite 0.7× its apical width (vs 0.6×); (iv) third tergite 2.6× wider than long (vs 3.3×); (v) fore wing vein m-cu not exactly parallel to 1-M (vs parallel); (vi) ratio of OD: OOL = 0.4 (vs 0.6). The comparative details are provided in Table II.

Crinibracon chromusae sp. n. differs remarkably from the only known Indian species C. indicus in not having following set of characters: (i) hind tibia and tarsi ivory white (vs all tarsi unicolourous in C. chromusae sp. n.); (ii) first and second metasomal tergites entirely dark brown to black (vs T1 except posterior lateral dark markings and T2 median broad triangular area with fine distinct markings laterally yellow in C. chromusae sp. n.); (iii) first metasomal tergite with the mid-longitudinal carina not or hardly expanded anteriorly (vs expanded anteriorly in C. chromusae sp. n.); (iv) female with 30 flagellomeres (vs not more than 26 in C. chromusae sp. n.).

Colour ( Figs 1 A −B). Head yellowish brown (face little lighter than frons), eyes dark brown, vertex yellowish brown, ocellar region dark brown, median/anterior ocellus dark brown, posterior ocelli yellow with dark brown patch in the middle, and occiput dark brown. Antennae dark brown (except scape slightly reddish dorsally). Mandibles yellow except dark brown apices. Mesosoma dark brown (except posterior-lateral corner of pronotum, anterior margin of lateral lobes of mesoscutum, posterior half of middle lobe of mesoscutum, scutellum and median carina of propodeum reddish brown). Legs yellow except extreme apices of coxae faintly dark. Wings faintly infuscate; fore wing with two brown bands, pterostigma, parastigma and veins dark brown. Metasoma: T1 (except posterior lateral dark markings), T2 median broad triangular area and fine distinct markings laterally, triangular medio-posterior area of T3, T4 and T5, and entire T6 yellow. Posterior margins of T2–T5 yellow.

Head ( Fig. 1 C). Setose and granulate. Antenna with 25–26 flagellomeres [holotype with 26]; terminal flagellomeres approximately 2.2–3.0× longer than wide. First flagellomere 1.2–1.3× longer than both second and third separately, latter being 1.2× longer than wide. F3 1.1× longer than F4. In dorsal view, length of eye 2.2× temple, temple gradually narrowed behind eyes; frons densely and evenly setose, finely punctate, and with a median ridge. Height of clypeus: inter-tentorial distance: tentorio-ocular distance = 7: 16: 12. Height of eye: width of face: width of head = 0.42: 0.42: 0.91. Shortest distance between eyes: maximum distance between eyes = 0.58. POL: diameter of posterior ocellus: shortest distance between posterior ocellus and eye = 8: 7: 17. Length of malar space 1.2× width of mandible. Vertex and occiput densely and evenly setose. Clypeus smooth.

Mesosoma ( Fig. 1 F). Mesosoma 1.6–1.7× longer than wide; mesoscutum densely setose; notauli prominent. Scutellar sulcus deep wide with strong crenulae. Scutellum and mesopleuron setose. Mesopleuron shallowly punctate except for central region; pleural suture weakly impressed, smooth; metapleuron long and setose. Metanotum narrow with a short median carina anteriorly. Propodeum shiny, shallowly rugulose with a complete median carina.

Table 1. Showing measurements of Crinibracon chromusae sp. n. types.

Table 2. Showing differences between Crinibracon chromusae sp. n. and closely allied Chinese species Crinibracon sinicus .

Indian species Chinese species Characters Crinibracon chromusae sp. n Crinibracon sinicus

Body length 3.2−3.7 3.6

Forewing length 3 3.8

Ovipositor length 0.6−0.7 0.3

Ovipositor length: forewing length 0.2 0.1

Antenna flagellomeres 25−26 -

Male antenna flagellomeres 22−25 25

Ratio of length of F3/F4 1.1 1.2 dorsal view (ratio of eye/temple) 2.2 2.0

Height of clypeus: inter-tentorial distance: tentori-ocular distance 7: 16: 12 4: 11: 5

POL: diameter of posterior ocellus: shortest distance between posterior ocellus and eye 8: 7: 17 4: 3: 5

Ratio of length of malar space: mandible width 1.2 1.3

Ratio of shortest distance between eyes: maximum distance between eyes 0.6 0.5

Mesosoma longer than wide 1.7× 1.5×

Fore-wing (length of SR1: 3-SR: r) 87: 30: 22 55: 17: 12

Fore-wing vein m-cu parallel to 1M Not exactly Yes

Fore-wing (2-SR: 3-SR: r-m) 9: 10: 6 12: 17: 8

Hind-wing (length of lr-m: SC + R1) 0.3 0.5

Second metasomal tergite (length: maximum width) 2.6 2.5

Fore femur: tibia: tarsus 46: 52: 23 10: 11: 4

Hind femur: tibia: basitarsus 59: 85: 32 6: 8: 3

Hind tibial spurs: hind basitarsus 0.3−0.4 0.2−0.3

First tergite: apical width 0.7 0.6 (maximum width: median length) 2.4 2.4 (maximum width: median length) 2.6 3.3

Wings ( Fig. 2 A). Fore wing- Length of SR1: 3-SR: r = 87: 30: 22; 2-SR: 3-SR: r-m = 9: 10: 6; length of m-cu: 2- SR + M = 5: 3; m-cu not exactly parallel to 1-M, 0.5× as long as 1-M. Hind-wing- M+CU: 1-M: 1r-m: 2-SC+R = 25: 63: 2: 14. Length of lr-m: SC + R1 = 10: 33 = 0.3.

Legs. Length of fore femur: tibia: basitarsus = 46: 52: 23; length of hind femur: tibia: basitarsus = 59: 85: 32; hind femur 3.4–3.9 times wider than long; hind tibial spurs 0.4 and 0.3× as long as hind basitarsus.

Metasoma ( Figs 1 G −I, 2B −D). Metasomal tergites 1−6 evenly with punctate-aciculate sculpture. Length of first tergite 0.7× its apical width. Second metasomal tergite 2.4× wider than long and third tergite 2.6× wider than long. Second metasomal tergites with a distinct mid-longitudinal carina. Ovipositor sheaths pointed apically. Ovipositor expanded apico-dorsally and with small ventral teeth. Length of setose part of ovipositor sheath 0.05– 0.07× fore wing length.

Male. Body length 3.1 mm. Antenna with 22–25 flagellomeres. Sublateral grooves of second tergite not very prominent. The median yellow line separating lateral patches T2–T5 is narrower as compared to females. Remaining characters and colouration like that of females.

Type material. Holotype ♀ ( NBAIR), INDIA, Karnataka, Bangalore, Yelahanka, 13.06 °N 77.35°E, 1.iv.2016, ex: pupa of Hasora chromus (Cramer) on Millettia (= Pongamia ) pinnata (L.) Panigrahi ( Fabaceae ) , NBAIR, Code 1416 . Paratypes: 5 ♀, 5 ♂ (NBAIR) [part of the same brood as holotype].

Etymology. The species is derived from host species name.

Biology ( Figs 4−5 ). Gregarious parasitoid of pupae of Hasora chromus (Cramer) (Hesperiidae) on Millettia (= Pongamia ) pinnata (L.) Panigrahi ( Fabaceae ). Three species of hyperparasitoids, Philolema braconidis (Ferrière) ( Hymenoptera : Eurytomidae ), Nesolynx javanica Ferrière ( Hymenoptera : Eulophidae ), and an Eupelmus sp. ( Hymenoptera : Eupelmidae ) emerged along with C. chromusae sp. n. from the pupae of H. chromus . All these species of parasitoids are known to be hyperparasitic on Lepidoptera through braconid cocoons.

Figures

FIGURE 1. Crinibracon chromusae sp. n. A. Female in habitus; B. Body in dorsal view; C. Head in frontal view; D. Vertex; E. Mesopleuron; F. Mesosoma; G. Metasoma with propodeum; H. Metasoma in dorsal view; I. Metasoma at an angle.

FIGURE 2. Crinibracon chromusae sp. n. (female) A. Wings; B. Apical segments of metasoma; C. Metasoma in ventral view; D. Metasoma in lateral view.

FIGURE 3. Crinibracon sinicus. A. Vertex; B. Mesosoma; C. Metasoma; D. Metasoma in lateral view; E. Female in habitus.

FIGURE 4. Host- Hasora chromus. A & B. Pupae of H. chromus with larvae of Crinibracon chromusae sp. n. C. Pupa of H. chromus showing adult emergence of Crinibracon chromusae sp. n.; D. Pupae with emergence holes; E. Host plant Millettia pinnata showing excreta of H. chromus caterpillar on the ground; F. Eggs of H. chromus; G. Caterpillar of H. chromus; H. Adult female in ventral view; I. Adult male in ventral view.

FIGURE 5. Hyperparasitoids. A. Philolema braconidis; B. Nesolynx javanica; C. Eupelmus sp.