Bombyx orientalis Fabricius, 1793

Zolotuhin, Vadim V., 2018, Nomenclature and synonymic remarks on two species of Eupterotidae (Lepidoptera) described by Johan Christian Fabricius, and notes on related species, Zootaxa 4471 (2), pp. 381-386 : 382-386

Bombyx orientalis Fabricius, 1793

Entomologia systematica emendata et aucta … 3(1): 422. TL: “in India orientali. Dom. Lund”. The taxonomic situation with Bombyx orientalis has been complicated for a long time. The type of the species has been considered lost as no specimen so labeled has been found in the Copenhagen, Glasgow or London museum collections.

According to Zimsen (1964) the abbreviation “Dom. Lund” ( Fig. 2 ) given in the original description by Fabricius means the collections of Sehested and Tønder Lund who were in active contacts with Fabricius, and also exchanged specimens. The collections of Sehested and Tønder were finally united by the latter. In 1809, Tønder Lund went to Norway to take a seat in the Government committee but the ship he travelled on was lost at sea. The collection was then sold to the Danish State, and in the larger part was preserved in the Zoological Museum of Kiel University. Today, Fabricius’ types from Kiel are on prolonged loan to the Zoological Museum of the University of Copenhagen. Although no specimen labeled Bombyx orientalis has been found in this collection, recently, a specimen with the label ‘ hibisci ’ was discovered ( Fig. 5 ). Surprisingly, this specimen is quite distinct from the Hunterian’s Bombyx hibisci , and belongs to a species of a different taxonomic group. The specimen bears a small hand-written ancient label “Mus. Seh. e T. L.” ( Fig. 6 ), which stands for “Museo Sehested e Tønder Lund”. Notably, this specimen fits the original description of orientalis , which reads ‘yellow wings with three ferruginous fasciae on the fore wing, and [with] a single fascia on the paler hind wing’. The so called third ‘striga’ is a spotted submarginal fascia which is better visible in fresh specimens.

Thus, the question was whether this specimen really could be a type of Bombyx orientalis . Four arguments can be listed to affirm this idea: 1. it is a specimen from Fabricius’ collection, 2. it corresponds well to the description, 3. the specimen originates from Lund’s collection, and 4. the specimen is taxonomically distinct from Bombyx hibisci .

Another question is: could the specimen found be a syntype of Bombyx hibisci? Several points argue against this possibility. It is known that some specimens originally belonging to Thott had been kept in both Fabricius’ and Lund’s collections ( Zimsen, 1964) but these specimens are labeled “e Mus. Thott”. The original label of our specimen, however, reads “Mus. Lund”. Thus it is not one of Thott’s specimens.

Although the identification label ‘ hibisci ’ appears to have been written a long time ago, it is not in Fabricius’ original hand. Zimsen (1964) writes that in the middle of XIX century ‘the unpardonsible mistake was made of copying the original labels and then placing the specimens in the general collection of the museum but without keeping the original labels’. At that time, identifications for many specimens were incorrect. Its identification mistake as Bombyx hibisci was started probably with Aurivillius work (1897) concerning Fabricius’ types; and it was based on wrongly written label ‘Hibisci’ put under the specimen. Alternatively, this label was added to the specimen between 1775 and 1793, in the time when only hibisci was known.

Therefore can now designate a lectotype of the taxon to stabilize its nomenclature. It is possible that the specimen is a holotype by monotypy. However, to avoid assumption on holotype, a lectotype and not a holotype is here designated (recommendation 73F of the International code of zoological nomenclature 1999: 80).

The specimen is a male in rather good condition bearing the handwritten label “Mus. Seh. e T. L.” and a larger handwritten rectangle with ink inscription “ B. Hibisci ”. Two more labels appear to have been added later. One is a large bottom rectangle with type-written “Bombus [sic!] Hibisci F. | Syst. Ent. 1775 p. 564 | Aurivillius 1897 p. 155 (100)”. The second one is a rather modern label, written with ball pen: “e/f. Kiel Coll.”. The specimen will be supplied with a standard red rectangular label with corresponding printed text.

The species is attributed here to the genus Eupterote Hübner, 1820 , and the following new combination and synonymy are established:

Eupterote orientalis ( Fabricius, 1793) , bona species, comb. nov.

= Dreata geminata Walker, 1855 , syn. nov., syn. corr., List of the specimens of lepidopterous insects in the collection of the British Museum 4: 907. TL: “ Ceylon ”. Holotype: ♂ ( NHMUK) [studied].

= Dreata Anada Moore, 1860 , syn. nov., A catalogue of the lepidopterous insects in the museum of the Hon. East-India company 2: 365. TL: “Canara”. Holotype: ♂ (NHMUK) [studied].

= Brachytera phalaenaria C. & R. Felder, 1874, syn. nov., Reise der österreichischen Fregatte Novara um die Erde in den Jahren 1857, 1858, 1859. Zoologischer Th., Lepidoptera 4: 2, Taf. 95, fig. 1. TL: “Ceylon”. Holotype: ♂ [probably lost].

= Eupterote auriflua Moore, 1884 , syn. nov., Transactions of the entomological Society London: 364. TL: “Hab. Malabar”. Syntypes male, female (NHMUK) [studied].

= Eupterote geminata var. hebes Grünberg, 1914 , syn. nov., Entomologische Rundschau 31: 75. TL: “ Ceylon ”. Holotype: ♂ ( ZMHB) [studied].

Taken into consideration as the species was described from ‘ India orientali’, the type locality for orientalis should probably be corrected as [ Sri Lanka] because three conspecific taxa were described from Ceylon, and Dreata anada was described from the Indian subcontinent. The species is seemingly native to southern India and Sri Lanka. Northwards, in the Himalayas, it is replaced by a closely related species, Eupterote gardneri Bryk, 1950 , stat. nov., which differs by the reduced submarginal spots. The following new synonymy can be therefore established:

Eupterote gardneri Bryk, 1950 stat. nov. as bona species

Eupterote geminata (Walker) ssp. gardneri Bryk, 1950 , Entomologisk Tidskrift 71(1): 59. TL: “ New Forest (Dehra Dun), U. P., India ”. Holotype: ♂ ( RMS) [studied].

= Eupterote bifasciata Kishida, 1994 , syn. nov., Moths of Nepal 3: 65, fig. 434, pl. 77: 7. TL: [ Nepal] “ Kosi, Chittrei”. Holotype: ♂ (NHMT) [studied].

Taking into consideration the remarkable sexual dimorphism typical for most species of the genus, it can be assumed that the species originally described as Dreata lineata Walker, 1855 , List of the specimens of lepidopterous insects in the collection of the British Museum 4: 907 from North India after a monotypic female (NHM, studied—Fig. 15), is a member of the same species. If so, the name will have a priority over gardneri Bryk, 1950 . However, additional investigation is necessary to resolve this problem.

The two following short notes are here provided for Dreata lineata Walker, 1855 .

1. It was thought that the taxon Messata lineata Walker, 1855 , represented the male of Dreata lineata , perhaps was just the (erroneously given) description of the same type specimen (both names were cut from Walker’s description and used to designate the single female holotype of Dreata lineata Wlk., 1855 in NHMUK—Fig. 15). It is surely not so. Both names were established for different sexes, and one of them was established in the genus Dreata Walker 1855 in which moths of Eupterote -like appearance were combined, whereas the second name was introduced in Messata Walker, 1855 , which combined moths of Sangatissa Moore 1883 or true Messata of similar appearance. The male type specimen of Messata lineata Walker, 1855 , which is supposed to be preserved in NHM, has not been found so far. However, the specimen is not assumed to be lost but hidden among the extensive material stored at the museum. Therefore, Messata lineata Walker, 1855 , List of the specimens of lepidopterous insects in the collection of the British Museum 5: 1108. TL: “North India ”, holotype: ♂ (NHMUK), probably should be removed from the synonymy of Dreata lineata .

2. The mysterious Eupterote balwanti Bhasin, 1944 (Indian Journal of Entomology 6: 139, fig. 1) described from India, “Garhwal, U.P.” (♂ holotype reported to be in the coll. Forest Research Institute, Dehra Dun, India) perhaps also belongs to Dreata lineata . However, its status remains unresolved until type specimens or topotypical material can be studied. According to a drawing given in the original description, the taxon is close to Dreata lineata Walker, 1855 . No information could be obtained from the Forest Research Institute of Dehra Dun despite several requests.

One more species of this group, the pale Eupterote primularis Moore, 1884 (Transactions of the Entomological Society of London: 371. TL: “Hab. Coonoor, Nilgiris; Shevaroy Hills”) is not conspecific with any of the species considered above despite of certain external similarity. It is a separate species native to Central and Southern India (Fig. xx). Pale ground color, dark yellow and oblique postmedial fascia beginning near a forewing apex are diagnostic characters of this species.

Figures

FIGURES 1–2. Original descriptions of taxa by Fabricius. 1. Bombyx hibisci; 2. B. orientalis.

FIGURES 3–6. Type specimens of Eupterote ssp. described by Fabricius, adults and their labels. 3. Bombyx hibisci, ♂ lectotype (HMAG); 4. B. hibisci, ♂ paralectotype (HMAG); 5. Bombyx orientalis, ♂ lectotype (ZMKU/ZMUC); 6. The same, inventory label enlarged.