Euploea dorippus Klug, 1845

Vane-Wright, Richard I., 2020, Euploea dorippus Klug, 1845: species, semispecies, subspecies, junior subjective synonym of Danaus chrysippus chrysippus (Linnaeus), and / or form - what does Klug's dorippus represent? (Lepidoptera: Nymphalidae, Danainae), Nota Lepidopterologica 43, pp. 117-138 : 117

Euploea dorippus Klug, 1845

Euploea dorippus Klug, 1845: text (signature h[iii]), pl. 48, figs 1-5. Male and female syntypes, Sudan: [New] Dongola, Dunqulah, 19°10'N, 30°29'E, and Ambikol, 18°03'N, 31°31'E, leg. C.G. Ehrenberg & W.F. Hemprich ( Baker 1997: 194) (material apparently lost - not in Museum für Naturkunde, Berlin: Olivier and Nekrutenko 2000).

Limnas dorippus (Klug): Butler, 1886: 758. Butler acted as first reviser, restricting application of the name Euploea dorippus to Klug 1845: pl. 48, figs 1-4 (see also Swinhoe 1885: 126). [In this paper Butler excluded the specimen represented by Klug 1845: pl. 48, fig. 5, to become part of the type series of a new nominal taxon, Limnas klugii (Butler, 1886: 758 - type locality currently accepted to be Somalia: inland south of Berbera).

Type material.

Klug’s (1845) description of Euploea dorippus was based on at least two males and one female collected by Ehrenberg and Hemprich at two localities on the banks of the Nile in northern Sudan, ca 150 km apart, in May and July 1822 ("Habitat ad Dongalae novae castra Aethiopiae in Echii floribus Maio; ad Ambukohl Iulio."). The precise locations, as noted above, have been given by Baker (1997); a very helpful map is presented by Chester Bradley (1968). Their approximate location is plotted on Fig. 1 .

Klug’s original description was in Latin: "Euploea alis testaceis, nigro-limbatis, limbo, subtus praesertim, albo-punctato, posticis maculis, subtus albo-notatis, in disco nigris. Mas. Fem. …. Magnitudine E. Chrysippi, cui valde affinis. Caput et thorax nigra, albo-punctata. Antennae nigrae. Alae fulvo-testaceae, supra margine omni, sparsim albo-punctato, nigro; anticae macula insuper triangulari costali media, posticae maculis discoidalibus quatuor (in femina tribus) nigris; subtus alae basi fulvae, limbo maculisque discoidalibus nigris ubique maculis albis ornatis. Pedes nigri. Abdomen fulvo-testaceum, subtus album. Variat uterque sexus alis posticis medio albis. "

This has kindly been translated by Tony Galsworthy as follows: "A Euploea [now Danaus] with orange wings, bordered with black, the border, particularly below, spotted with white, hind wings black on the disc marked below with white. Male. Female. …. Size as E. chrysippus, to which it is certainly related. Head and thorax black, spotted with white. Antennae black. Wings fulvo-testaceous, upperside with the margin completely black, sparsely spotted with white; fore wing upperside with a triangular costal marking, hind wings with four black discal marks (three in female); underside wings fulvous at base, with black border and discal marks, everywhere ornamented with white markings. Legs black. Abdomen fulvo-testaceous, white below. Both sexes vary in the white in the middle of the hind wings."

Given the three different phenotypes originally illustrated by Klug (Fig. 2 ), it might be considered desirable to select a lectotype. This, however, is not possible in terms of an actual specimen as it appears all the original material is lost ( Olivier and Nekrutenko 2000). Moreover, with respect to the taxonomic application of the name, unless we insist that Klug was working from a mixed series of two or more species (possibly the case based on the conclusions of Smith et al. 2005), the type localities are accurately known and sufficiently close together (ca 150 km) that any application dependent on geo-location is not likely to be equivocal. Thus I consider making a lectotype (or neotype) designation unnecessary (even undesirable) at the present time with respect to application of Euploea dorippus as an available name (see Discussion).

Before considering these matters further, the various ways in which the name dorippus has been applied over the past 175 years are enumerated and exemplified.

Previous applications of the name Euploea dorippus .

Ignoring differing generic combinations, there are at least nine ways in which the available name Euploea dorippus has been employed since it was first proposed as a new species: 1) separate monotypic species ( Danaus dorippus ); 2) separate polytypic species; 3) form of a polymorphic D. dorippus ; 4) subspecies of a polytypic D. dorippus ; 5) semispecies of superspecies Danaus [chrysippus]; 6) subspecies of species D. chrysippus ; 7) form of a monotypic but polymorphic D. chrysippus ; 8) form of D. chrysippus subspecies chrysippus ; and 9), form of D. chrysippus subspecies aegyptius (Schreber, 1759). It could also have been used as a form of subspecies D. chrysippus dorippus or of semispecies D. [chrysippus] dorippus, but I have not seen this done explicitly - and insofar as David Smith and his co-workers have regarded the ‘dorippus’ forewing pattern to be fixed in semispecies or subspecies dorippus in its core area ( Smith 2014, page 188; Smith et al. 2016 - but see Discussion), it would be an unlikely previous usage. Instances of all nine uses that I have found are listed sequentially below (ciphers in square brackets refer to the usages listed above).

Literary synonymy of Euploea dorippus .

Euploea dorippus - Klug 1845: text (signature h[iii]), pl. 48, figs 1-5. [1]

Danais dorippus - Peters 1862: 371; Godman 1885: 537; Marshall & de Nicéville 1882: 52; Pagenstecher 1902: 129. [1]

Limnas dorippus - Moore 1883: 238; Swinhoe 1885: 126. [1]

Danaida dorippus - Aurivillius 1910a: 2, 1910b: 72 [1]

Danaus dorippus - Smith et al. 2005. [1]

Danaus dorippus bataviana (Moore, 1883) - Smith et al. 2005. [2]

Danais dorippus var. klugii - Holt White 1894: 49. [2 or 3]

Danaus dorippus f. dorippus - Suffert 1900: 116. [3]

Danaus dorippus dorippus - Smith et al 2005. [4]

Danaus [chrysippus] dorippus - Smith et al. 2010; Smith 2014; Gordon et al. 2014, 2015. [Note - square brackets around chrysippus used here indicate that dorippus is a member of a superspecies of which Danaus chrysippus is the first-named taxon, in accordance with the proposals of Amadon (1966; see also Helbig et al. 2002).] [5]

Danaus chrysippus dorippus - Bryk, 1937: 66; ? Talbot 1943: 121; Gordon 1984; Smith et al. 1997, 1998, 2002, 2016, 2019; Lushai et al. 2003a, 2003b, 2005; Herren et al. 2007; Traut et al. 2017; Williams 2018; Duplouy and Hornett 2018; Martin et al. 2019. [6]

Limnas chrysippus var. dorippus - Butler 1897: 923. [6 or 7]

Danais chrysippus var. dorippus - Kirby 1871: 7; Trimen 1887: 53. [6 or 7]

Salatura chrysippus var. dorippus - Ormiston 1918: 5. [6 or 7]

Danaida chrysippus var. dorippus - Ormiston 1924: 3. [6 or 7]

Danaida chrysippus f. dorippus - Fruhstorfer 1910: 194; Hulstaert 1931: 27. [7]

Danais chrysippus f. dorippus - Manders 1912; Woodhouse and Henry 1942: 39, pl. 2 fig. 3. [7]

Danaus chrysippus f. dorippus - Woodhouse 1952; Donahue 1962; Gifford 1965; Owen 1971; Dickson and Kroon 1978; Kielland 1990; Idris and Hassan 2012; Idris 2013; Hassan et al. 2013. [7]

Danaus chrysippus chrysippus f. dorippus - Carcasson 1963: 21; Larsen 1990, 1991; Gillett 1998; ? Braby et al. 2015; van der Poorten & van der Poorten 2016. [8]

Danaus chrysippus aegyptius f. dorippus - ? Talbot 1943: 120; Pierre 1974; Rothschild et al. 1975; D’Abrera 1980; Ackery & Vane-Wright 1984; Smith et al. 1988; Ackery et al. 1995; d’Abrera 1997. [9]

Danaus dorippus

This usage reflects its original, species-level status - having first been introduced by Klug (1845) as a species of Euploea Fabricius, 1807. Fabricius included three nominal species in Euploea , one being Papilio plexippus L., the type species of Danaus Kluk, 1780. The current usage of Euploea was not finally stabilised until publication of Opinion 163 (ICZN 1945), which fixed Papilio corus Fabricius, 1793, as its type species. Papilio corus is now used as the name for a subspecies of the butterfly currently known as Euploea phaenareta (Schaller, 1785).

Species level status for dorippus was maintained by Aurivillius in several publications, notably the very influential ‘Seitz’ (Aurivillius 1911, as Danaida dorippus ). In that work he states that the forewing apex is brown-yellow without any subapical white band, and "the hindwing is not white [sic]". He does acknowledge that it is often only regarded as a form of D. chrysippus , "but of this there is no sufficient evidence" (Aurivillius, 1911: 12). From Aurivillius (1899: 32/33) it is evident that he regarded Butler’s Limnas klugii as a synonym of dorippus , but recognised Danais dorippus ab. ‘albinus’ Lanz, 1896, as a variety, and gave Klug’s 1845: pl. 48 fig. 5 “var.” the infra-subspecific name Danais dorippus ab. ‘infumata’. This suggests that Aurivillius (see also Suffert 1900) conflated Klug’s dorippus with the all-orange ground colour morph that also lacks all trace of the forewing pre-apical transverse white spots ( ‘transiens’) as well as hindwing discal white - a morph which, as shown above, Klug did not describe or illustrate. Thus regardless of Swinhoe’s (1885, p. 126) earlier stricture “Klug’s type of L. dorippus has white hind wings, a fact which appears to have been entirely overlooked", this misapplication of Klug’s name to the all-orange phenotype has continued ever since.

Despite Aurivillius’s great authority, during most of the rest of the 20th century dorippus was generally regarded as a form and/or subspecies of D. chrysippus , not a separate species. Particularly important in this shift was Poulton’s (1924) short paper entitled " Danaida chrysippus L. and D. dorippus Klug, proved by breeding to be forms of the same species". However, separate species status was accorded once more by Smith et al. (2005). Following a series of complex analyses based on mitochondrial 12S rRNA and COI sequences, the authors concluded that " dorippus … is the basal clade of the genus and is reinstated as the species D. dorippus " ( Smith et al. 2005: 1291). Furthermore, the authors regarded it as composed of two subspecies: D. dorippus dorippus (range: Somalia, Kenya, Tanzania, Uganda, Sudan, Ethiopia, Arabia, Iran, Pakistan (Baluchistan), India (Sind, Kutch), and D. dorippus bataviana (Moore, 1883) from SE Asia.

Compared with all other interpretations of this group, these were unexpected and radical findings. Five years later Smith et al. (2010) announced "we wish to renounce our decision to restore dorippus to full species status, based solely on the evidence of mtDNA-based phylogenies …. and designate D. c. dorippus (stat. rev.) as its fourth African semispecies". This is so despite the fact that fig. 3.3. in Smith (2014, p. 129, p. 153) shows D. chrysippus dorippus twice - once (dorippus-NB haplotype) as the sister clade to all other taxa of Danaus (including D. plexippus ), and second (dorippus-DP haplotype) as sister to Danaus chrysippus bataviana . In contrast, as pointed out by Brower (2016) "A recent molecular systematic paper by Braby et al. (2015) does not support Smith’s results and shows a monophyletic D. chrysippus including African and Asian forms with very low levels of sequence divergence."

David Smith’s research group has not been consistent with application of semispecies/subspecies rank. In recent publications (e.g. Smith et al. 2016, 2019; Traut et al. 2017; Martin 2019) they have reverted to calling dorippus a subspecies of D. chrysippus .

Danaus [chrysippus] semispecies dorippus

Smith and his associates ( Smith et al. 2010, summarised in Smith 2014: fig. 2.34) developed a classification of Danaus chrysippus in the Afrotropical Region based on a hypothesis of past incipient geographical speciation in Africa during the late Pleistocene. They recognised a superspecies with four semispecies in the Afrotropics, for which they applied the following names (without the use of square brackets, a convention adopted here based on Amadon 1966):

• D. [c.] chrysippus in the north-east, to include North Africa, Egypt, northern Sudan (including the type localities for Euploea dorippus ), the Canary Islands and Mediterranean eastwards to China etc.);

• D. [c.] alcippus (Cramer) in West Africa north of the Equator and south of the Sahara;

• D. [c.] dorippus in the Horn of Africa region (including the type localities for Limnas klugii ); and

• D. [c.] orientis (Aurivillius) in most of Africa south of the Equator, including the Malagasy region.

However, according to the Smith scheme, all these populations are now in contact within a very extensive east African 'Hybrid Zone’ covering much of Uganda, Tanzania, Kenya, Ethiopia and north of the Horn through Eritrea to Yemen. Although genetically compatible only to varying degrees involving several complex factors (e.g. localised infections with male-killing bacteria - Jiggins et al. 2000), due to the migratory nature of these butterflies, extensive gene flow nonetheless occurs. As a result, all of the various phenotypes can be found well beyond their core zones, including those of the other semispecies (within Africa, most notably the case with semispecies orientis - Smith et al. 2019, fig. 2). Within the Hybrid Zone, Smith (2014) has recognised many forms and genotypes as the result of hybridization between the semispecies, where they apparently coexist, in some sense, as sympatric taxa. Thus although the core area for supposedly ‘pure’ D. [chrysippus] semispecies dorippus is Somalia, eastern Ethiopia and north-eastern Kenya, Smith (2014: fig. 4.1) describes the polymorphism at Dar es Salaam, some 600 km south of this core area, as the result of hybridization between all four semispecies.

Danaus chrysippus subspecies dorippus

Talbot (1943: 121) stated "The form dorippus appears dominant in Abyssinia, Somaliland, Kenya and Tanganyika Territory; it may be considered almost as an eastern race." Subsequently dorippus has quite often been used for the name of a subspecies of D. chrysippus centred on the Horn region (e.g. Gordon 1984; Herren et al. 2007; Lushai et al. 2003a; Smith et al. 1997, 2002). As noted above, Smith et al. (2016, 2019) have recently reverted to this usage.

Figures

Figure 1. Outline distribution map for the four subspecies or semispecies of Danaus chrysippus in mainland Africa, as recognised by David Smith and co-workers (e. g. Smith et al. 2010 fig. 1). This map is based on Lushai et al. 2003 fig. 1 (for which the original caption reads: ' geographical distribution of the subspecies of D. chrysippus in the Afrotropical region, showing the approximate boundaries of the hybrid zone ... '). Note this extensive ' hybrid zone' in eastern Africa. The large five-pointed star in northern Sudan is centred on the type localities of D. dorippus (Klug), in an area supposedly occupied by subspecies D. c. chrysippus or semispecies D. [c.] chrysippus. Not one of the three phenotypes exhibited by the type material of D. dorippus (Fig. 2) corresponds to the phenotype regarded as typical of the Horn of Africa subspecies D. c. dorippus or semispecies D. [c.] dorippus (as currently named). The small five-pointed star in northern Somalia is centred on the approximate type locality of D. klugii (Butler) (See text).

Figure 2. The five images published by Klug (1845, plate 48) to illustrate his original description of Euploea dorippus. a, b - pl. 48 figs 1,2 (" E. dorippus mas. "); c, d - pl. 48 figs 3, 4 (" E. dorippus fem. "); e - pl. 48 fig. 5 (" E. dorippus mar. var. " - this " variety " was later included as part of Limnas klugii Butler, 1886, and subsequently given the infra-subspecific name Danais dorippus ab. ' infumata' (Aurivillius 1899 )). See text.