Ernestinus Distant, 1911

Yeshwanth, H. M. & Konstantinov, Fedor V., 2021, Review of the plant bug tribe Eccritotarsini (Hemiptera: Heteroptera: Miridae) of India and Sri Lanka with description of two new genera and six new species, European Journal of Taxonomy 745, pp. 1-69 : 6-7

Ernestinus Distant, 1911

Figs 2A–B , 5H–I , 12–13 , 26

Ernestinus Distant, 1911a: 311 .

Pycnofurius Poppius, 1912: 21–23 (syn. by Carvalho 1952: 55).

Ernestinus – Lin 2001a (review of Taiwan fauna). — Yasunaga & Ishikawa 2016 (revision).

Type species

Ernestinus mimicus Distant, 1911 (by monotypy).

Diagnosis

Recognized by the following characters: coloration distinctly black and white, with head, pronotum, clavus, transverse spot on medioapical part of corium, apex of cuneus, and cells uniformly dark brown to black, remaining part of hemelytron and legs contrastingly whitish ( Figs 2A–B , 26B–C, F ); antenna whitish with entirely or apically darkened segment II; pronotum densely and coarsely punctate, campaniform, distinctly raised posteriorly and covering entire mesoscutum and base of scutellum; calli located far from anterior margin of pronotum, delimited by shallow sulcus, medially separated by deep pit; genital capsule boat-shaped, without distinctive ornamentation ( Figs 12A , 13A ); aedeagus simple, tubular, usually C-shaped, with endosoma non-retractable, entirely expanded from phallotheca in repose, weakly sclerotized, and not clearly divided from phallotheca ( Figs 12F , 13H ).

Host

Adults and nymphs feed and aggregate on the abaxial surfaces of leaves of Araceae plants, mainly Alocasia , Amorphophallus , and Colocasia spp. Yasunaga & Ishikawa (2016) provided a uniquely detailed account of the natural history of the genus and each included species.

Distribution

Widely distributed in the Oriental Region and spanning north to Nepal, Taiwan and southwestern Japan.

Remarks

Based on external morphology and the male genitalia, Stonedahl (1988: 43) outlined a group of six related genera including Ernestinus, Distant, 1911 , Eofurius Poppius, 1915 , Microbryocoris Poppius, 1914 , Myiocapsus Poppius, 1914 , Palaeofurius Poppius, 1912 , and Stylopomiris Stonedahl, 1986 . Of these, Microbryocoris , Myiocapsus , and Stylopomiris readily differ from Ernestinus in several autapomorphic traits (see Stonedahl 1986, 1988 for details). Eofurius , a monotypic genus known from a single male collected in Philippines ( Poppius 1915), has not been studied since the original description but differs from Ernestinus spp. in the small size and substantially produced clypeus. Palaeofurius contains three species from Papua New Guinea and appears to be most closely related to Ernestinus due to the same pattern of coloration, structure of pronotum, parameres, and characteristic aedeagus (see Carvalho 1981). Yasunaga & Ishikawa (2016) correctly pointed out that this taxon might be a synonym of Ernestinus but refrained from formal action due to the lack of material.

Species of Ernestinus share a number of common features in the structure of head, pronotum and especially male genitalia with those of Ambunticoris Carvalho, 1981 , a genus containing three species from New Guinea and Sulawesi (Konstantinov & Zinovjeva 2006). However, it clearly differs from that genus and other Oriental eccritotarsines in the color pattern and many additional traits documented by Yasunaga & Ishikawa (2016). Ernestinus brevis Lin, 2001 described from Taiwan ( Lin 2001a) is an exception in having pale greenish pronotum, scutellum and hemelytron; its generic placement requires further verification ( Yasunaga & Ishikawa 2016). The genus was originally described from Sri Lanka and currently includes 19 Southeast Asian species ( Yasunaga & Ishikawa 2016). Examination of available material allowed us to note this genus from India for the first time.

Key to species of the genus Ernestinus of India and Sri Lanka

1. Antennal segment I dark brown with a dirty yellow base, segment II at least 1.3× as long as head width. Scutellum black ( Fig 2A ). Left paramere strongly swollen at middle, with apical process long, almost straight, abruptly bent at base. Right paramere flag-shaped, wide ( Fig. 12 ) ................. .................................................................................................................... E. mimicus Distant, 1911

– Antennal segment I whitish yellow, segment II short, subequal to head width. Scutellum reddish orange medially ( Fig. 2B ). Left paramere thinner, gradually curved along entire length, apically tapering. Right paramere bulbous ( Fig. 13 ) ............... E. ramkeshariae Yasunaga & Ishikawa, 2016

Figures

Fig. 2. Habitus of Ernestinus, Harpedona and Lopidolon spp. A. Ernestinus mimicus Distant, 1911, ♂, UASB. B. Ernestinus ramkeshariae Yasunaga & Ishikawa, 2016, ♂, UASB. C. Harpedona sanguinipes Distant, 1904, ♂, UASB. D. Harpedona vittlaensis sp. nov, ♀, UASB. E–F. Lopidolon dandeliensis sp. nov., UASB. E. ♂. F. ♀.

Fig. 5. Dorsal view and label data of type specimens. A–C. Dioclerus bengalicus Stonedahl, 1988, ♀, holotype, BPBM.D–E. Dioclerus lutheri Stonedahl, 1988, ♂, holotype, AMNH_PBI 00338430, FMNH. F–G. Dioclerus praefectus Distant,1910, lectotype, AMNH_PBI 00340384, NHM. H–I. Ernestinus mimicus Distant,1911, ♂, syntype, AMNH_PBI 00085668, BMNH(E) 1633157, NHM. J–K. Harpedona marginata Distant, 1904, ♂, holotype, NHM. L–M. Harpedona sanguinipes Distant, 1909, ♂, lectotype, NHM.

Fig. 12. Male genitalia of Ernestinus mimicus Distant, 1911, UASB. A. Genital capsule in dorsal view. B–C. Right paramere in dorsal view and ventral views. D–E. Left paramere in dorsal and lateral views. F. Aedeagus in lateral view.

Fig. 13. Male genitalia of Ernestinus ramkeshariae Yasunaga & Ishikawa, 2016, UASB. A. Genital capsule in dorsal view. B–D. Right paramere. B. Dorsal view. C. Ventral view. D. Apex, magnified. E–F. Left paramere. E. Dorsal view. F. Lateral view. G. Apex, magnified. H. Aedeagus in dorsal view.

Fig. 26. Habitats and living specimens. A–C. Ernestinus ramkeshariae Yasunaga & Ishikawa, 2016 on Colocasia esculenta. A. Nymphs. B–C. Adult. D–F. Ernestinus mimicus Distant, 1911 on Lagenandra sp. D. Aquatic habitat. E. Nymph and freshly moulted adult. F. Adult. All specimens at UASB.