Chrysomya megacephala Fabricius, 1794

Ramaraj, Paulchamy, Selvakumar, Chellappa, Ganesh, Arumugam & Janarthanan, Sundaram, 2014, Report on the occurrence of synanthropic derived form of Chrysomyamegacephala (Diptera: Calliphoridae) from Royapuram fishing harbour, Chennai, Tamil Nadu, India, Biodiversity Data Journal 2, pp. 1111-1111 : 1111

Chrysomya megacephala Fabricius, 1794

Materials

Type status: Other material. Occurrence: catalogNumber: I/D 28: 3 male and I/D 29: 3 female ; recordedBy: Dr. S. Janarthanan; individualCount: 25; sex: 12 male, 13 female; disposition: Zoological Survey of India, Southern Regional Centre, Chennai, Tamil Nadu, India; Taxon: kingdom: Animalia; phylum: Arthropoda; class: Insecta; order: Diptera; family: Calliforidae; genus: Chrysomya; specificEpithet: megacephala; taxonRank: species; vernacularName: Oriental latrine fly; taxonomicStatus: accepted; Location: country: India; stateProvince: Tamil Nadu; municipality: Chennai; verbatimLocality: Royapuram fishing horbour; verbatimElevation: 2 m; verbatimLatitude: 13°07' 44.73 N; verbatimLongitude: 80°17' 52.70 E; Identification: identifiedBy: P. Ramaraj & C. Selvakumar; dateIdentified: 29 Jan 2014; identificationReferences: Senior-White et al., 1940; identificationRemarks: Eye facets of upper two-thirds greately enlarged and sharply demarcated from small facets of lower third; Event: samplingProtocol: Hand picking; eventDate: 2013-12-22; Record Level: institutionCode: University of Madras, Chennai

Diagnosis

Larva: Fully mature third instar muscoid-shaped (11 mm length), composed of 12 segments with pointed anterior and blunt posterior end (Fig. 2a). Cephaloskeleton present in anterior end; dorsal cornu longer than ventral cornua; accessory sclerite, parastomal sclerite present; anterodorsal process apparent (Fig. 2b). Anterior spiracle possessed eight to 12 marginal branches (Fig. 2c). Dorsal cuticular spines between the prothorax and mesothorax arranged single, each having one to three dark pointed tips (Fig. 2d). Inner dorsal tubercle moderate between middle dorsal tubercle and outer dorsal tubercle, with latter tubercle largest; a pair of the posterior spiracles clearly visible at the caudal end (Fig. 2e). Peritreme incomplete and heavily pigmented as a dark structure encircling three relatively straight spiracular openings (slits), with middle slits appearing slightly bent inward (Fig. 2f).

Pupa

Larger in size than larvae; cylindrical in shape (Fig. 3a). A pair of anterior spiracles located laterally on the prothorax at the anterior tip (Fig. 3b). A pair of posterior spiracles located prominently on the contracted surface of caudal region. Each spiracle more or less an oval shaped peritreme, encircling three straight spiracular slits (Fig. 3c).

Adult

Male (Fig. 4a): Body length 10-11 mm.

Head: Eye facets of upper two-thirds greatly enlarged and sharply demarked from small facets of lower third (Fig. 4c). Antenna short, postpedicel four times length of pedicel, pedicel dark brown, third brownish; arista dark brown, long plumose; palpi yellowish and slender (Fig. 5a). Thorax: Prostigmatic bristles present; anterior and posterior thoracic spiracles dark brown. Wings: Stem-vein with a row of setulae on upper posterior side; upper surface of lower lobe of squama hairy; upper squama white, partly dark margined; lower squama brown (Fig. 5b). Abdomen: Genital tergites bluish with black hairs; inner forceps elongated, outer forceps reduced (Fig. 5c); anterior paramere wide, slightly curved anteriorly; posterior paramere bifurcated at end; acrophallus wide at end and with a wide stakled projection posteriorly (Fig. 5d).

Female: (Fig. 4b). Body length 10-11 mm.

Head: Eyes separated by one-quarter total width of head; facets uniformly small; frons clearly separated; widest part of frons more than width of ocellar triangle; frontal reddish to black, with small hairs on the upper part; frontal bristles short and weak; parafrontalia slightly narrower than width of frons, covered with golden tomentum, but appearing black towards vertex in certain lights; parafacilia yellowish brown with silvery pollen and white hairs (Fig. 4d).

Molecular identification and DNA barcoding

The 651 bp mitochondrial cytochrome c oxidase subunit I (COI) sequences of Chrysomya megacephala (sdf) were 100% identical with available NCBI database sequences of Chrysomya megacephala using BLAST analysis. These mtCOI gene sequences of Chrysomya megacephala were submitted to NCBI database (Accession No. AB910389-male; AB910390-female) and DNA barcodes were generated for both the sexes based on their COI sequences using Barcode of Life Database (BOLD system; Process ID SPLID013-13 and SPLID033-14).

Distribution

South India - Tamil Nadu (Chennai); Kerala (Calicut); North India - West Bengal and rapidly throughout the continent.

Ecology

Life cycle: Second and third instar larvae of Chrysomya megacephala (sdf) were collected from decaying fishes of Royapuram fishing harbour of North Chennai, Tamil Nadu, South India. Adults emerged in the rearing chamber 7-9 d after pupation. Mating began 2 d after emergence and oviposition occurred at 3-4 d of age and laid egg mass on pieces of spoiled chicken in a squat cup. Each egg mass contained 200-300 eggs. Eggs held at 28 °C hatched on 1 d. Second instars emerged 2 d after hatching, becoming 3rd instar 2 d later, and then pupation occurred 4-6 d.