Research Article |
Corresponding author: Anna K. Hundsdoerfer ( anna.hundsdoerfer@senckenberg.de ) Academic editor: Lauri Kaila
© 2020 Anna K. Hundsdoerfer, Ian J. Kitching.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Hundsdoerfer AK, Kitching IJ (2020) Morphological evolution in Hyles Hübner, 1819 hawkmoths (Lepidoptera, Sphingidae): reconstructing the ancestral Hyles habitus. Nota Lepidopterologica 43: 181-210. https://doi.org/10.3897/nl.43.49512
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Molecular phylogenetic studies suggest that similar wing and body patterns in the hawkmoth genus Hyles Hübner, [1819] do not necessarily reflect a close phylogenetic relationship. To improve our understanding of morphological evolution in these organisms, 75 characters derived from the external adult morphology are explicitly coded and analysed in a maximum parsimony cladistic framework. The results corroborate the hypothesis that wing and body patterns have indeed reappeared in different parts of the phylogeny but the underlying genetic mechanism remains to be determined. By reconstructing the suite of ancestral states of the morphological characters using Bayesian inference, we derived an approximation of the appearance of the proto-Hyles species. The overall habitus of this moth does not display a combination of characters found in any extant Hyles species. Rather, the forewings are most like those of members of the Hyles euphorbiae-complex but with better developed antemedial and postmedial lines, the hindwings are typical Hyles, and the abdominal pattern most closely resembles that of Hyles euphorbiarum (Guérin-Méneville & Percheron, 1835), but with one fewer pairs of black subdorsal patches. Within the context of the subtribe Choerocampina and Sphingidae more generally, the proto-Hyles reconstruction does not resemble any other species apart from Rhodafra opheltes (Cramer, 1780), but this appears to be another instance of convergent pattern expression.
Molecular phylogenetic studies of the genus Hyles Hübner, [1819] (Lepidoptera: Sphingidae) have led to the realisation that similar wing and body patterns in this genus do not necessarily reflect a close phylogenetic relationship (
As in other groups of hawkmoths, Hyles moths from arid regions are often paler, with less contrasting and more homogeneous wing markings. Breeding experiments in which siblings were reared at different temperatures (
However, to date no study has explicitly coded external Hyles morphology and analysed the data in a cladistic framework to increase the understanding of morphological evolution in these insects.
The present paper has three aims: 1) to investigate in detail the morphological variation within Hyles by explicitly coding a suite of morphological characters (including representatives of several other Choerocampina genera as outgroups), then analysing these data using maximum parsimony methods; 2) to compare the results with the relationships postulated from the analyses of molecular data; and 3) to reconstruct the ancestral state suite of the morphological characters and thus the appearance of the proto-Hyles species.
The study included 218 individuals of Choerocampina, an ingroup comprising 193 samples of Hyles species and subspecies and 25 outgroup samples from other genera. The identification and the taxonomy follow
Data for 75 anatomical characters were obtained from the head (4), legs (3), thorax (6), abdomen (16); forewing pattern (40) and hindwing pattern (6). Character definitions, descriptions and explanations of character states are provided in Appendix I. Observations of pinned adults were made under a stereomicroscope. Selected characters are illustrated in Figures
The data set of character states for the 218 individuals is presented in Suppl. material
Specimens from the following collections were examined during the study: Natural History Museum, London, UK (
Maximum parsimony analyses were implemented using WinClada version 1.00.08 (
Bodies (without wings, antennae) of (a) Hyles vespertilio (Switzerland, same individual as Figs
To reconstruct the ancestral Hyles wing pattern, we reanalysed the slightly augmented dataset used in the ancestral state analysis in
Analysis of the 75 morphological characters (Suppl. material
Within Hyles, both EW consensus trees (Suppl. material
Analysis of the morphological data set (Suppl. material
Wings (right side) of (a) Theretra oldenlandiae (no data, MTD), (b) Hyles livornica (Italy, same individual as Figs
For 64 of the 75 characters, the maximum likelihood ancestral state reconstruction analysis yielded an unequivocal ancestral state assignment. For the remaining 11 characters with equivocal states, the state with the largest unequivocal state percentage was chosen to be represented in the reconstruction and the alternatives disregarded. The reconstruction of the ancestral states of the morphological characters within Hyles, illustrated as the habitus of a proto-Hyles moth (Fig.
A major challenge in this study was to disentangle the complex homologies of the wing and abdominal pattern elements. However, as many of the relationships represented in the consensus trees based on morphological characters reflect external similarity and sometimes former taxonomy, we appear to have interpreted these homologies correctly. For example, H. tatsienluica is placed within H. livornica and subgenus Danneria is consistently recovered as monophyletic (Suppl. material
The reconstruction of the proto-Hyles (Fig.
The EU’s Improving Human Potential program SYNTHESYS [grant numbers GB-TAF-3410, GB-TAF-5177] enabled A. K. Hundsdoerfer to undertake collaborative study of morphology of Hyles at the Natural History Museum, London, UK. We are particularly grateful to Dr Christian Schmidt for his pencil drawings of morphological structures and to Markward Fischer for their digitisation (both Senckenberg Dresden).
Explanation of characters and conventions used in coding the morphological data matrix.
PREAMBLE
• The terms “anterior” and “posterior” refer to the forewing of a moth with its wings conventionally spread (i.e., the wings are not in resting position over the body), such that the costa delimits the anterior margin of the forewing.
• The following gives the equivalents between the terminology adopted here for the transverse lines across the wings and that of Derzhavets (1984) (PM: postmedial; SM: submarginal; M: marginal):
PM1+_2 = MU1
PM3 = M1
PM6 = E
SM = Tu
M =T
• T1 to T10 refer to tergites 1 to 10 of the abdomen respectively.
• References to the online available colour photographs on the Sphingidae Taxonomic Inventory are included for colour characters.
It should be noted that individual specimens, not species, were coded and so, as a result of individual intraspecific variation, other specimens of the same species may show different states for some characters.
HEAD
1: Dorsal antennal scaling, colour; concolorous along entire length (0) (Fig.
The character state “concolorous” generally refers to antennae in Hyles that are uniformly white. However, the outgroup taxa and some very dark individuals of Hyles can be uniform shades of grey, brown or pink. The antennae of Hyles lineata are pale grey basally and so the contrast with the white tip is not as great as in some other species but were still coded as 1. The antennae of some taxa (e.g., Deilephila elpenor, Xylophanes libya, X. loelia) are white for most of their length with only the distalmost ten flagellomeres having darker scaling. These taxa were coded as “0”.
2: Labial palp segment 2, lateral hairs protruding through general scaling, presence; absent (0) / present (1) (Fig.
3: Labial palp segment 2, lateral hairs protruding through general scaling, if present, formation into a longitudinal crest; irregular, diffuse band or patch (0) (Fig.
4: Labial palp segment 1, scaling at apex on inner side, regularity; irregular (0) (Fig.
The form of the apical scaling of the inner side of the labial palp segment 1 was coded from
LEGS
5: Arolium pad, presence; absent (0) (Fig.
A fully developed arolium pad is large (≥ ½ length of the claws) and broadly ovoid. In the vestigial condition, it is small (≤ ⅓ length of the claws) and narrowly ovoid or rectangular (but nonetheless discernible as a distinct structure). When only the base of the arolium is present, and the pad is represented by a minute nipple-like structure or is missing entirely, the arolium pad is coded as absent.
6: Foreleg basitarsus outer row of spines, spines, size and number (compared to other rows); similar in size and number (0) (Fig.
In some specimens, the spines of the outer row are similar in length to the surrounding scales and require careful observation to confirm their presence.
7: Foreleg basitarsus outer supernumerary spines, presence (at least near the base); absent (0) (Fig.
If only one spine is out of line at the base of the basitarsus, this was not considered to be a supernumerary spine. The number of supernumerary spines can vary between the left and right legs of the same individual. Specimens Hyles centralasiae 271594, H. exilis 251533 and H. e. euphorbiae 271762 have no supernumerary spines on the right foreleg but two on the left; they were nevertheless coded as “0”.
THORAX
8: Tegula, outer edge, coloration; ground colour (0) (Fig.
The outer edge of the tegula is white or pale buff-coloured, thus strongly contrasting with the darker olive-green or brown scaling of the tegula body, in all taxa except two species of Xylophanes and Hyles vespertilio.
9: Tegula outer edge, if paler, inner black edge, presence; absent (0) (Fig.
The amount of black scaling is quite variable, ranging from mere traces, detectable only under stereomicroscopic magnification and requiring the moving apart of other scales to observe (e.g., several Hyles apocyni and both subspecies of H. hippophaes), to a distinct stripe. Any presence of black was coded as “1”.
10: Tegula inner edge, coloration; ground colour (0) (Fig.
Where the inner edge of the tegula is paler than the ground colour, it is usually white or cream-coloured. In a few specimens (e.g., some Hyles sammuti), it has a pinkish tone.
11: Tegula median line, presence; absent (0) (Fig.
This line is generally narrow, straight or curved, and is metallic golden-yellow in colour. However, in Deilephila askoldensis, it is broader and more diffuse, and in D. elpenor, it is additionally dark pink. The median stripe is absent in the pink “form porcellus” of D. porcellus that was coded here and so this species was coded as “0”. However, there is a diffuse dark pink stripe in some specimens of the pinkish-brown “form rosea” (e.g.,
12: Pale thoracic median line, presence; absent (0) (Fig.
This line is coded as absent in Deilephila porcellus, but this was difficult to determine due to a general blurring of the pattern in this species.
13: Pale thoracic median line, if present, shape; single broad dorsal line (0) (Fig.
ABDOMEN
14: Dorsal abdominal line, presence; absent (0) (Fig.
This line was coded as present even if it was broad and diffuse or reduced to a series of isolated spots on the posterior margins of the tergites. In some specimens, these spots may be merged into a general pale posterior margin to the tergites. Several specimens were coded as “?” because the abdomens were missing (due to genital dissection prior to this study) or worn. The abdomen of the holotype of Hyles churkini had been “washed” as part of the genitalia preparation procedure, which removed much of the dorsal scaling; it and the paratype male were coded from pre-dissection colour photographs provided by A. Saldaitis (pers. comm.).
15: Dorsal abdominal line, if present, colour; paler than ground colour of tergites (0) (Figs
The abdominal line in Deilephila elpenor was coded as “0” although it is a darkish pink against an olive-green ground (STI 863). The line was not coded as “1” in D. askoldensis as the entire dorsum is only slightly paler and there are clearly pale fringes to the tergites (STI 861).
16: Dorsal abdominal line, if present, form; single (0) (Fig.
17: Dorsal abdominal line, if present, form; continuous narrow line (0) (Fig.
Specimens were coded as “3” when the spots form part of a continuous pale posterior fringe to the tergites. In most instances of state “2”, the line is visible between all the spots but in some cases (e.g., Hyles tatsienluica), the line is visible only on T1 and T2 anteriorly, and T7 and T8 posteriorly. When the line is only vaguely visible on T7/T8 or T8 (e.g., H. t. tithymali 271939), or when the dorsal line is essentially ground colour, appearing paler in comparison to more lateral darker areas (e.g., H. dahlii 271419), specimens were coded as “3”. Hyles lineata was coded as “1” as the line is generally continuous and narrow, although on some tergites in some individuals it can be slightly interrupted on the posterior margins (where, also, there are no white spots). In some H. perkinsi (e.g., 271628), there is a diffuse band of whitish scales along the dorsum, with a slightly less diffuse patch in the fringes. As there is dark olive brown scaling lateral to this, before the black spots, these specimens were coded as “2”. In H. nervosa 271553, there are median spots on T5 and T6 only; in others, very weak spots are discernible; all coded as “3”. In two others, no spots can be seen. In H. dahlii 271424, there is a spot on T3 only (although the other segments are worn). In H. tithymali mauretanica 274431, there are a few (maybe < 5) pale scales on the margin of T7 only; this specimen was coded as “0”.
18: Median pair of black spots in posterior fringe of tergites of abdominal segments A3-6, presence; absent (0) (Fig.
Careful observation was required when coding characters 18–23 so as not to interpret the dark, heavily sclerotized scales along the edge of the tergites as black top-layer scales. The median pair of black spots is also present on A2 in Hyles lineata, H. livornica and H. livornicoides, but can be difficult to see in pale or greasy specimens, especially in H. livornicoides.
19: Black dorso-lateral spot on posterior part of abdominal segment A2, presence; absent (0) (Figs
The spots are present but very faint in Deilephila askoldensis.
20: Black dorso-lateral spot on posterior part of abdominal segment A3, presence; absent (0) (Figs
21: Black dorso-lateral spot on posterior part of abdominal segment A3, if present, size; A3; covering only a part of the segment, always leaving an anterior area of pale scaling (0) (Figs
Hyles livornicoides 272011 has a worn abdomen and although the presence of a black spot on A3 can be deduced from the few scales that remain, its extent cannot be determined; hence this specimen was coded as “?”.
22: Black dorso-lateral spot on posterior part of abdominal segment A4, presence; absent (0) (Fig.
This spot was coded as present even if it is restricted to the fringe of the tergite.
23: Black dorso-lateral spot on posterior part of abdominal segment A4, if present, size A4; covering posterior half of segment (0) (Figs
In Hyles nervosa 271553, this spot is weakly developed (black scales intermixed with some ground colour scales) but still stretches over about half the length of the segment, and so was coded as “1”. In the H. stroehlei male, the black fringe to A4 is visible; in the female, it would also appear to be present as determined from the pre-dissection photograph.
24: Black dorso-lateral spot on posterior part of abdominal segment A5, presence; absent (0) (Figs
25: Black dorso-lateral spot on posterior part of abdominal segment A6, presence; absent (0) (Figs
In Hyles annei 271815 and H. euphorbiarum 813596, this spot is very small; these were both coded as “1”. In H. annei 271811 and H. euphorbiarum 813551, the spot is a barely visible slightly darker shade; these were coded as “0”. In H. salangensis, the spots gradually become smaller and fainter from A2 to A6 and are sometimes not visible on the last of these segments. Although often small and faint on A5 and A6, they are still present, resembling in form those on A4 in H. nervosa 271553.
26: Dorso-lateral pale scales in fringes of tergites A4-6, presence; absent (0) (Fig.
These scales form a pale cream or white posterior fringe to the tergites in the taxa that have them. In some outgroup taxa, they are restricted to a pair of dorso-lateral spots.
The scales can be short (as in Hyles livornica and H. livornicoides) or rather long (as in H. annei). The spots are present but very faint in Deilephila elpenor. In Hippotion celerio and Basiothia charis, there are smaller silvery-white patches in the fringes that form part of the interrupted dorso-lateral longitudinal stripes. These are considered homologous with the dorso-lateral pale scales in other taxa and so coded as “1”. In B. schenki, there are white spots in the gold stripe on the fringes on T5 and T6 that are considered homologous the dorso-lateral pale scales in other taxa and so coded as “1”.Two Rhodafra marshalli have complete paler fringes (pale beige rather than white but were still coded as “1”) whereas R. marshalli 272081 lacks all pale scales, possibly because it is worn (and so was coded as “?”). In worn R. opheltes, the marginal lanceolate scales are somewhat golden and give the impression of a pale fringe; such specimens were coded as “0”. In Hyles lineata and H. euphorbiarum, there are some small white patches in the middle of T3-6 dorso-laterally, but none in the fringes, so these species were coded as “0”.
27: Dorso-lateral pale scales in fringes of tergites A4-6, if present, extending towards midline no further than mesal margin of black spots (0) (Fig.
In state 0, the median edges of the black spots and all pale patches and fringes are in line antero-posteriorly, leaving a broad median gap to the pale midline (if present). In some outgroup taxa, the pale scales are restricted to small spots, but these are not mesad of the inner margin of dorso-lateral longitudinal stripes (which occupy the same position as the black patches in other taxa). In state 1, the fringes extend further mesad by a distance about half way to the midline, leaving a narrow gap to the midline (if present). In state 2, the pale fringes are continuous across the entire tergite and include the midline pale spots (if present). In the Hyles stroehlei male, the white fringes clearly extend mesad of the inner edge of the black spots on A2 and A3; in the female they do not but this is because the black spots and associated white patches are also extended mesad by the same amount, making the mesal edges of all these elements appear in line. The female was thus coded as “1”.
28: Dorso-lateral pale scales in fringes of tergites A4-6, if present, colour; white, cream or pale yellow (0) (Fig.
In Hippotion celerio, there are smaller silvery-white patches in the fringes.
29: Dorso-lateral gold stripe, presence; absent (0) (Fig.
FOREWINGS
30: Black basal spot, presence; absent (0) (Figs
The basal spot is spot G of Derzhavets (1994). The base of vein Cu in Theretra oldenlandiae has some slightly darker scales but these are brown rather than black and do not constitute a clear spot; this species was coded as “0”.
31: Basal band, presence; absent (0) (Figs
The basal band (band F3 of Derzhavets 1994) occupies the basal third of the discal cell and the area posterior to vein Cu (Fig.
32: Antemedial band, anterior part in discal cell, presence; absent (0) (Figs
The antemedial band arises from the inner edge and traverses the wing across the discal cell halfway between the subbasal line and the apex of the cell as defined by the origin of vein M2. Specimens were coded as “-” if the middle of the discal cell and basal part of cell f (see below) are dark, even if the area posterior to cell f is pale and no line is seen; i.e., the antemedial band may exist only within the discal cell to costa (where it is too dark to be seen). A darker crossbar in the discal cell (e.g., in some Hyles gallii, notably H. gallii 813579) is interpreted as the remains of the antemedial line.
33: Antemedial band, anterior part in discal cell, if present, angle to costa; transverse (0) (Fig.
In state 0, the antemedial line curves to run transversely across the discal cell to the costa. In state 1, it runs parallel to the postmedial lines and through the discal spot.
34: Postmedial lines PM1+PM2, presence; absent (0) (Fig.
Postmedial lines PM1 and PM2 are visible as separate lines in Hippotion, Theretra and Xylophanes. In all other taxa in the present study in which they are discernible, PM1 and PM2 are fused into a single line (see character 35). Specimens are coded as “-” if the basal parts of cells a-b (see below) are dark, even if the area more towards the wing base is pale and no line is seen; i.e., PM1+PM2 may exist only within the basal parts of cells a-b where it forms the “comma mark” (see character 37) (Fig.
35: Postmedial lines PM1 and PM2, if present, fusion; not fused (0) (Figs
Postmedial lines PM1 and PM2 are considered fused if only a single, broad line is visible.
36: Postmedial lines PM1+PM2, if present, direction; running to apex (0) (Figs
In state 0, PM1+PM2 do not necessarily have to reach the apex, only run towards it. In state 1, the distal angle of curvature towards the costa is almost 90°.
37: Postmedial lines PM1+PM2, if distally curving to costa beyond M1, development; developed in nearly its entire length, from inner edge to costa (0) (Fig.
State 1 is the pattern element commonly referred to as the “comma mark” (Fig.
38: Postmedial line PM3, presence; absent (0) (Figs
This line runs within the pale medial band. If PM3 and PM4 are fused (as in Basiothia schenki), both are coded as present.
39: Postmedial line PM4, presence; absent (0) (Figs
This line runs within the pale medial band. If PM3 and PM4 are fused (as in Basiothia schenki), both are coded as present.
40: Postmedial line PM6, presence; absent (0) (Fig.
41: Postmedial line PM5, degree of development; curving costad distal to Rs4 (0) (Fig.
Postmedial line PM5 is present in all specimens studied and so was not coded as a separate presence/absence character. In state 0, PM5 curves towards the costa distal to Rs4, meeting it nearly at right angles. In state 1, PM5 curves in the opposite direction, running to the wing apex, and generally merging with the apical stripe (Fig.
42: Postmedial lines PM5 and PM6, relative orientation; subparallel from apex to inner margin (0) (Fig.
The critical element of this character is the divergence of the two lines, not the colour between them. In Rhodafra opheltes and most Hyles, the colour between the divergent PM5 and PM6 is a characteristic olive-green to olive-brown and forms the distinctive triangular postmedial pattern element. PM5 and PM6 are divergent in several other taxa and the colour between the lines varies: Deilephila elpenor (khaki), D. porcellus (mustard yellow), D. askoldensis (pinkish-brown), Hyles vespertilio (slightly darker grey with a slight yellowish tinge), Chaerocina dohertyi (brown) and C. jordani (slightly darker yellowish green).
In R. marshalli, PM6 is entirely absent and so is coded as “-” for this character.
43: Postmedial lines PM5 and PM6, coloration between PM5 and PM6; uniform from apex to inner margin (0) (Figs
In specimens coded as “1”, the pale section can extend basally from CuA1 as far as CuA2 (in Hyles perkinsi, H. wilsoni and some H. n. orientalis, PM6 is absent distal to CuA1/CuA2).
In R. marshalli, PM6 is entirely absent and so is coded as “-” for this character.
44: Postmedial line PM5, if present, shape; straight or evenly curved (0) (Figs
45: Postmedial line PM5, if present, between CuA1 and the inner margin, shape; straight or slightly concave (0) (Figs
This character captures the degree to which PM5 runs straight to the inner margin at an acute angle (Figs
46: Postmedial line PM6, if present, shape between CuA2 and inner margin; straight or slightly convex (0) (Figs
This character was coded using the same protocol as for character 45 but the straight edge is placed between the points where PM5 crosses CuA2 and where it meets the inner margin.
47: Veins between PM1 and PM6, colour; concolorous with background along whole length (0) (Figs
When the veins are paler, sometimes the bases of the veins can be dark, especially Rs4. Vein M2 can be dark due to the presence of very strong spots in cells c and d. Hyles robertsi elisabethae 4314 is worn but those scales that are left suggest that the veins are concolorous with the background.
48: Veins across postmedial band, if concolorous with pale medial band, extent; paler at least distally, along a few veins (0) (STI 1339) / paler along at least half of some veins and paler in the position of the middle of the band (1) (Fig.
49: Postmedial line PM7, presence; absent (0) (Figs
This line is often referred to as the submarginal line. Individuals in which PM7 appears to be indicated by a broad, diffuse shade were coded as “0”, because this is not a clearly demarcated line. In Hyles calida, PM6 appears to fade out into that shade, which makes it difficult to determine, but such specimens were nevertheless coded as “1”.
50: Postmedial line PM7, if present, sharpness; distinct line (0) (STI 2856) / indistinctly defined line (1) (STI 1303).
51: Postmedial line PM8, presence; absent (0) (Figs
This line is often referred to as the marginal line.
52: Inner margin between PM5 and PM6, fringes, colour relative to area bounded by PM5, CuA2, PM6 and inner edge of fringes; concolorous (0) (Fig.
53: Line of white scales in basal third of cell between costa and radius, presence; absent (0) (Fig.
54: Line of white scales in basal half of discal cell, along anterior margin, presence; absent (Fig.
The degree of development of this line of white scales is variable from the wing base to the middle of the cell; if any white scales at all were observed, the specimen was coded as “1”.
In Rhodafra opheltes, the discal cell basally has a linear patch of cream scales along the posterior margin, the same colour as the pale medial band. As these scales are not white, this species was coded as “0”. In Hyles perkinsi, and to a lesser extent in H. wilsoni, there are scattered white scales over almost the entire wing upperside. However, as this do not form a line, these species were coded as “0”.
55: Costal cell ground colour; concolorous with basal band (0) (Fig.
The costal cell is cell K of Derzhavets (1994). In state 1, there is a clearly visible change in the ground colour of the costal cell at the point level with distal edge of the basal band, and the basal section of the costal cell is usually concolorous with the basal band. Care had to be taken to ensure that it was the ground colour of the costal band either side of the subbasal line that was evaluated. The subbasal line itself, when it is visible in this area, is invariably darker than the costal band and this must be ignored. In Rhodafra opheltes, the costal cell is very pale basally and gradually becomes darker towards the apex. As it is essentially concolorous in the area in question this species is coded as “0”. In the Hyles tithymali group, which were coded as “1”, the colour difference can be seen although it is very slight and requires careful observation. This area of the forewings in Hyles robertsi robertsi 271539 is greasy and discoloured, and so the specimen was coded as “?”.
56: Discal cell between subbasal line and apex, colour; entirely dark (0) (Fig.
State 0 is equivalent to the presence of the basal part of spot F2 of Derzhavets (1994).
With regard to coding pale coloration in the discal cell, the area in question extends from the subbasal line distally to the origin of M2 (Fig.
57: Scaling in cell a (Fig.
This is the distal part of spot F1 of Derzhavets (1994) and is in cell Rs3-Rs4 (Fig.
58: Scaling in cell b (Fig.
This is the basal part of spot F1 of Derzhavets (1994) and is in cell Rs4-M1 (Fig.
59: Scaling in cell c (Fig.
This is the distal part of spot D of Derzhavets (1994) and is in cell M1-M2 (Fig.
60: Scaling in cell d (Fig.
This is the antero-distal part of spot D of Derzhavets (1994) and is in cell M2-M3 (Fig.
61: Scaling in cells e & f (Fig.
These are the antero-distal and postero-distal parts of spot F2 of Derzhavets (1994) and are in cells M3-CuA1 and cell CuA1-CuA2 (Fig.
H. dahlii 813555 is a generally dark moth but although there are darker scales in cells e and f, they are not the same colour as the area between PM5 and PM6; hence this specimen was coded as “0”.
62: Suffusion in the median area between PM2 and PM5 and M1 and CuA1 (Fig.
This suffusion is a wash of darker scales extending from the costa towards PM5 along the entire length of the wing, parallel to the costa. In Hyles, it usually results in the cream colour of the medial band becoming restricted to a narrow band along the basal edge of PM5 (e.g., H. annei, H. biguttata, H. calida). It is usually broader towards the inner margin of the wing and may even reach PM5 on the inner edge of the wing. Care had to be taken when coding pale specimens (mostly populations from arid or semi-arid habitats; e.g., H. nicaea orientalis), in which the suffusion may not be very dark. In state 0, there may be suffusion as far as PM2. This was not coded as presence because of observational difficulties in very spotty moths. If the wing is uniformly darker, this character is coded as “0” (e.g., H. wilsoni, H. perkinsi, H. vespertilio, some H. nicaea). In H. gallii MTD TW 4367, a particularly dark specimen, there is a slight suffusion between M3 and CuA1 only; this is coded as “0”.
There is a similar wash of darker scaling in Deilephila porcellus, D. elpenor and D. askoldensis 813599. These species were also coded as “1”. The general grey coloration in Hyles vespertilio is not interpreted as a suffusion and this species is coded as “?”. It is unclear whether the pattern in H. perkinsi and H. wilsoni involves a suffusion or not, and thus these are also coded as “?”. This area in H. nicaea lathyrus is heavily patterned with transverse striae but if these are ignored, then there is no suffusion. The gap between PM2 and PM5 in H. dahlii is very narrow but contains no suffusion. In H. t. tithymali 271939, there is some suffusion between M3 and CuA2, which is coded as “1”.
63: Dark shading of a similar colour and tone to the area between PM5 and PM6 in cells c and d, if present, apical shape; extending apically and filling width of both cells c and d (0) (Fig.
This character codes for the shape of spot D of Derzhavets (1994). Specimens were coded as “-” if the shading was absent from either or both cells c and d. The condition in which the dark shading in both cells is apically rounded (state 1; e.g., Hyles euphorbiarum) is easily recognizable. However, care had to be taken when coding the other two states, particularly with regard to cell c, in which either dark scales extend distally towards the position of PM1+2 and fill or nearly fill that area (state 0; e.g., H. lineata, H. livornica, H. t. tithymali), or the anterior-distal triangle of cell c is entirely pale (state 2; e.g., H. euphorbiae, H. nicaea, H. t. mauretanica). In the first case, there may also be long hair-like white scales overlying the dark scales that fill the anterior-distal triangle, giving the impression that the apex of the dark shading in cell c is rounded, and thus superficially resembling the condition coded for by state 2. These long white scales were ignored for the purposes of coding the present character. In some Hyles nicaea (e.g., H. n. nicaea 813544, H. n. castissima 813547, H. n. orientalis 271670 and H. n. orientalis 271666), the element in cell c is slightly divided apically, but these specimens were nevertheless coded as “2”. In Deilephila askoldensis, the rounded shape consists of dark scaling in cells b, c and d, but since the shape resembles the rounded element of cells c and d in Hyles species, Deilephila askoldensis was nevertheless coded as “1”. In Hyles biguttata 271823, the apex of the c-d spot is rather pale, giving the impression of state 1. However, the two spots are not as elongate as in those species with state 1 but are short as in species with state 2. In addition, the wings are worn and much of the pattern is less clear. Hence this specimen was coded as “2”. Hyles zygophylli is difficult to code as several specimens are apparently intermediate between states 1 and 2; they were coded as the state that they more closely resembled. Some H. nervosa (e.g., 271553) have a strongly developed PM1 +PM2 in cell c, which gives the impression that the dark pattern element reaches that far. However, this does not match the pattern coded as “1” in H. livornica and if PM1+PM2 is ignored, then these H. nervosa specimens are clearly state “2”.
64: Long hair-like scales on the inner wing margin near wing base, immediately distal to basal spot, colour; ground colour only (0) (Fig.
65: Additional long, hair-like scales, presence; absent (0) / present (1).
These long, hair-like scales are usually white, but they can be ground colour (e.g., Hyles centralasiae 271585, 271593, H. sammuti). They are additional to those scales coded in the previous character.
66: Anterior-distal triangle in cell c, if dark, apparent colour; as dark as rest of element (0) (STI 1310) / with overlying long pale hair-like scales that make it appear pale (1) (Fig.
In state 0, the anterior-distal triangle is as dark as the rest of the element more basal to it in the cell, and thus almost or completely reaches PM1+2. In state 1, this triangle is also dark but there are long, pale (usually white) scales overlying it that give the superficial impression that it is pale and thus appearing to obliquely truncate the element and superficially resemble state 2 of character 63. For taxa with states 1 or 2 for that character, character 66 is coded as “-”.
67: Longish white scales in distal half of discal cell, presence; absent (0) / present surrounding or immediately basal of the position of discal spot (1).
The degree of development towards the centre of the discal cell is variable. Hyles robertsi elisabethae 4314 was coded as “?” because the general degree of wear suggests that any white scales that may have been present have been lost. In H. nicaea castissima, the white scales are present but are difficult to observe against the general very pale beige ground colour. In H. siehei, some H. centralasiae, and H. e. euphorbiae 813554, the scales are present but beige or pinkish, rather than the usual white; these specimens were nevertheless coded as “1”.
68: Discal spot, presence; absent (0) (Fig.
The discal spot is situated just distal of the discal cell, posterior to vein M2. The apparently pale discal spots in Hyles vespertilio and H. perkinsi are due to long white scales at the apex of the discal cell and are not homologous with other white discal spots (e.g., Deilephila elpenor). These two species were thus coded as “0”.
69: Discal spot, if present, colour; dark (0) (Fig.
The colour of the discal spot in Hyles euphorbiarum is difficult to code because it is strongly reflective, the effect of which is to make it appear paler. However, the scales are darker than those surrounding them, and hence this species was coded as “0”.
HINDWINGS
70: Marginal band, colour compared to submarginal band; concolorous (0) (Fig.
This character was difficult to code in Deilephila elpenor because the medial and marginal bands are both pale pink and the submarginal band is only slightly darker pink. It was also difficult to code in D. askoldensis and Chaerocina jordani because the submarginal band is poorly developed (appearing only as a slight dark line distal of about M3). In Hyles siehei 271581, the submarginal band is a very broad pink shade. This specimen was coded as “2” because in H. sammuti 271694, there is a narrower shade of the same colour that was also coded as “2”. In H. gallii 4366, the marginal band between CuA2 and 1A+2A is paler with a distinct inner margin, whereas distal to CuA2 the marginal band absent (or at least very indistinct); nevertheless, this specimen was coded as “2”. In Hyles siehei ab. privata, the black submarginal band is absent and so this character and the two relating to its basal prolongations are all coded as “?”.
71: Medial band, distinct cream or white spot on inner margin, presence; absent (0) (Fig.
The pale spot has to be distinctly differentially coloured from the medial band and has to be on the inner margin. It is faint in Hyles vespertilio but present. In Xylophanes tersa, the whole medial band is primrose yellow; in X. loelia, the inner margin is beige; in Basiothia charis, the inner margin is concolorous with the medial area but there is a small beige patch near the tornus. All these species were coded as “0”. In Hyles lineata, the pink/white scales of the anal area of the hindwing are relatively sparse and seem to be easily lost, whence the white under-layer becomes prominent. Such specimens were coded as “0”.
72: Medial band, colour intensity; concolorous between Rs and CuP (0) (STI 1320) / medial band between Rs and CuA2 distinctly paler than between CuA2 and CuP (1) (STI 1303). The disjunction in colour intensity has to be abrupt to be coded as “1”. If the medial band only gradually becomes paler towards to costa then it is coded as “0”.
73: Inner edge of submarginal band, prolongation towards base along veins, presence; absent (0) (STI 1303) / present (1) (STI 1344 from Madeira).
Such prolongations are only coded as “1” if they are clearly and regularly present along at least M1 to CuA2 (Fig.
74: Inner edge of submarginal band, prolongation towards base between each of veins M1 and CuA2, presence; absent (0) (Fig.
As for character 76, such prolongations are only coded as “1” if they are clearly and regularly present between all five veins. Specimens in which there are one or two short prolongations between two or three of the veins, often on one wing only (as in some Hyles wilsoni) were coded as “0”.
75: Underside, black tornal spot, presence; absent (0) (STI 1350) / present (1) (STI 1303).
Care had to be taken not to code elements of the dorsal wing pattern that show through to the underside. To be coded as “1”, there must be a distinct spot. In Hyles apocyni SMTD MTD TW 4537 and H. hippophaes hippophaes 813567, there are only a few scattered scales in this area of the wing that do not coalesce into a distinct spot; these specimens were coded as “0”. In some H. nicaea, there is a series of closely spaced brown striae arranged into a patch as large as in other Hyles that are coded as having a tornal patch. Although these appear to be the same structures that form the darker patch in other Hyles, they do not coalesce into a uniformly dense patch and so were coded as “0”. In H. nicaea nicaea 813544 and H. nicaea nicaea 813545, however, there is such a coalescence and these specimens were coded as “1”.
References:
Danner F, Eitschberger U, Surholt B (1998) Die Schwärmer der westlichen Palaearktis. Bausteine zu einer Revision (Lepidoptera: Sphingidae). Herbipoliana 4: 1–368 (Textband), 1–720 (Tafelband).
Derzhavets YA (1994) Phylogenetic interrelations of the sphinx moths of the genus Hyles Hbn. (Lepidoptera, Sphingidae). Entomological Review 73: 34–52.
Rothschild LW and Jordan K (1903) A revision of the lepidopterous family Sphingidae. Novitates Zoologicae 9 (supplement): cxxxv + 1–972.
Table S1
Data type: matrix of characters and character states
Explanation note: Matrix of 75 characters and character states derived from the external morphology of 218 Choerocampina individuals, with a focus on the genus Hyles.
Table S2
Data type: label data
Explanation note: Locality and other label data for the specimens coded in Table S1.
Table S3
Data type: species characters and character states
Explanation note: Character states analysed for the ancestral state reconstruction and the suite of inferred states used to produce the illustration of the proto-Hyles moth shown in Fig.
Figure S1
Data type: figure
Explanation note: (a) Strict consensus tree (SCT) of the 82166 MPCs of length 432 steps found by analysis of the 75 morphological characters under EW. (b) 50% majority rule consensus tree (MRCT) of the 82166 MPCs of length 432 steps found by analysis of the 75 morphological characters under EW.
Figure S2
Data type: figure
Explanation note: Strict consensus tree of the 37 most parsimonious (fittest) cladograms found by analysis of the 75 morphological characters under implied weighting (IW) (K = 16).