Chilo sacchariphagus (Bojer, 1856)

Figs. 38, 99, 157.

Proceras sacchariphagus Bojer, 1856; Błeszyński 1966: 477 ( Chilo). Type locality: Mauritius

= Argyria straminella Caradja, 1926 c: 168; type locality: China, Tsingtan

= Borer saccharellus * Guenée, 1862: 70–71; type locality: Réunion; Tams 1942 (syn.)

= Chilo mauriciellus Walker, 1863 b: 141–142; type locality: Mauritius

= Chilo venosatus Walker, 1863 b: 144; type locality: Malaysia, Borneo, Sarawak; Bleszynski 1970: 183 (syn.)

= venosatum * Hua, 2005: 50

= Diatraea striatalis Snellen, 1890: 98, pl. 2 figs. 1–4; Hampson 1896: 953 (syn.)

= Chilo sacchariphagus indicus (Kapur, 1950: 414–415, pl. 6 figs. 3, 7, 13) (Proceras); type locality: India, Bihar, Pusa; Błeszyński 1966: 493 ( Chilo)

= Chilo sacchariphagus stramineella (Caradja, 1926: 168) ( Argyria); type locality: China, Tsingtau

MATERIAL

1 ♂, 2 ♀ (detailed information in Table S1; https://doi.org/ 10.5061/dryad.b8gtht7mh).

DIAGNOSIS

Chilo sacchariphagus, also known as the Spotted Borer or the Striped Stem Borer, is recognized by the striped forewings with a tiny dark brown cell spot in males, while female specimens are similar to those of C. suppressalis . This species can, however, be separated from other Chilo species by examination of the genitalia. In male genitalia (Fig. 99), the following characters separate this species: juxta plate short, broad, deeply notched, two arm projections conspicuously shorter as in other Chilo species; phallus with a row of 15-30 slender cornuti. In female genitalia (Fig. 157), the following characters separate this species: the antrum is well-marked, sclerotized; the ductus bursae has longitudinal ribs; and the corpus bursae is large, with one scobinate half (Anon, 2019; Bleszynski, 1970c). Bleszynski (1970c) discussed the differences in genitalia between the population from mainland China and Taiwan and that of the Philippines and Indonesia. He states that the “phallus in the specimens from Indonesia and Philippines is thinner and lacks the apical scobinations; in the ♀ genitalia the ductus bursae lacks the sclerite, but shows distinct longitudinal ribbing absent in the specimens from China and Formosa” (Bleszynski, 1970c).

DISTRIBUTION

EAST AFRICA; BANGLADESH; BRUNEI; CAMBODIA; CHINA; INDIA; INDONESIA (Borneo, Java, Bali, Sumatra, Celebes); IRAN; JAPAN; LAOS; MALAYSIA; PAKISTAN; PHILIPPINES: Luzon (Albay, Zambales); SINGAPORE; SRI LANKA; TAIWAN; THAILAND; VIETNAM (CABI Compendium 2019).

DNA BARCODING

The three specimens from the Philippines sequenced show identical DNA barcodes. Haplotype network reconstruction reveals that the Philippine haplotype is not shared with any other haplotypes retrieved from BOLD and GenBank and shows a p-distance of 2.4% to the closest conspecific specimen AGIMP002-12 from India. The highest distance observed is of 6.1% with specimen LSTEM508-18 from Java, Indonesia.

REMARKS

This species shows an extensive variation in genitalia, suggesting that it might indeed represent a species complex (Bleszynski, 1970c). Błeszyński investigated six specimens of this species from Benguet and Passay Rizal and two male specimens from Los Banos on Luzon, Philippines. This species is a major pest of sugar-cane in South-East Asia (Bleszynski, 1970c).