Anolis nitens (Wagler)

Myers, C. W. & Donnelly, M. A., 2008, The Summit Herpetofauna Of Auyantepui, Venezuela: Report From The Robert G. Goelet American Museum-Terramar Expedition, Bulletin of the American Museum of Natural History 2008 (308), pp. 1-147 : 102-107

Status of Anolis nitens (Wagler)

Draconura nitens Wagler (1830) was named with a brief four-line description in Latin (see below for the original description and translation). The type locality ‘‘America’’ is uninformative, and no other author seems to have examined the lost type specimen. Only seven years after its description, Duméril and Bibron appeared unable to diagnose the species for inclusion in the Erpétologie générale —the great herpetological synthesis of the time. Duméril and Bibron (1837: 91) placed Draconura nitens with a question mark in the synonymy of their new Anolis refulgens (type locality, ‘‘Surinam’’), a Schlegel label name. The new Anolis chryso- lepis was named a few pages later (Duméril and Bibron, 1837: 94–95).

A. A. Berthold, at the Zoological Museum in Göttingen, unsuccessfully tried to make some sense of the taxonomy under the subheading ‘‘Ueber das Genus Draconura Wagl’’. ( Berthold, 1840: 899; 1842: 17–21; ‘‘ 1843 ’’ [ 1842?]: 61–65).28 In recognizing Draconura, Berthold accepted refulgens over nitens , without concern for priority (not an established concept in those days), and added two additional species, chrysolepis and his new 12-striata, the last of which is now recognized as a synonym of Anolis or Norops auratus (a species which Wagler had placed in the monotypic genus Norops immediately following the description of Draconura ).

Several other 19th-century authors simply overlooked or ignored Duméril and Bibron’s ‘‘?’’ in the Erpétologie générale and accepted nitens (Wagler) without question and with little or no discussion as the senior synonym of refulgens (Wiegmann, 1834: 16; Gray, 1840: 114; 1845: 207; Fitzinger, 1843: 69; Peters, 1863: 142; Bocourt, 1874: pl. 16, fig. 25; Boulenger, 1885: 91–92).

Use of either nitens or refulgens as a valid specific name in most of the secondary 19thcentury references above are simple listings of little taxonomic importance, although Bocourt (1874) added head and digit drawings of the Paris Museum holotype of refulgens . During all this time, Anolis chrysolepis Duméril and Bibron (1837: 94–95) also was recognized as a valid species by most of these and other authors.

In the Catalogue of the Lizards in the British Museum, Boulenger (1885: 89–90) identified 15 specimens as Anolis chrysolepis but none as A. nitens . Boulenger’s account for A. nitens (pp. 91–92) appears to have been paraphrased from Duméril and Bibron’s (1837: 91–94) original description of A. refulgens . (Boulenger correctly translated the symbols 99 and 999 used by Duméril and Bibron for cm and mm, but comparison

28 The first Berthold citation is only a brief synopsis, given for completeness; the remaining two citations are differently paged preprint and journal versions of the same paper. See Myers and Böhme (1996) for a summary and bibliography of the herpetological part of ‘‘Berthold’s rich and varied scientific career’’.

of head, body, and tail measurements show that Boulenger’s ‘‘108’’ mm total length is a misprint for 180 mm.) Boulenger’s Catalogue provided the starting point for several 20th-century authors who were to deal with actual specimens from Venezuela and British Guiana (now Guyana).

In the early 20th century, Fowler (1913: 171–172) described as a Venezuelan subspecies Anolis nitens bondi . 29 Lidth de Jeude (1917: 46) mentioned Anolis nitens in Suriname, and Barbour (1934: 143) followed Boulenger in listing it as a senior name over refulgens . Finally, field experience with living animals was provided by Beebe (1944), who recognized both Anolis chrysolepis and Anolis nitens as the most abundant anoles at Kartabo, British Guiana, and Caripito, Venezuela. Anolis chrysolepis was considered an usually striped species with ‘‘infinite variation’’, whereas A. nitens was characterized mainly by ‘‘a series of posteriorly pointed V-shaped markings on the back from shoulder to beyond the base of the tail’’.

Shreve (1947: 524) saw through the extensive color variation and synonymized Anolis chrysolepis under Anolis nitens , closing the argument with field notes for two Venezuelan specimens ‘‘taken in copulation, the female having the light vertebral streak [a common female color morph of some anoles] of chrysolepis , the male presenting the nitens pattern of chevrons, their apices directed posteriorly’’. But Shreve also is the first author to question the adequacy of Wagler’s (1830) description of nitens :

As the original description of nitens is not very diagnostic, there appears to be some doubt about the applicability of the name. If it cannot be used, then chrysolepis , which was much better diagnosed, can be employed. (Shreve, 1947: 524)

Subsequent use of nitens as the valid name for Venezuelan specimens (Roze, 1958a: 246; Test et al., 1966: 13–14; Donoso-Barros, 1968: 112) derived from Shreve’s action, but chrysolepis

29 Fowler’s bondi was ‘‘described from a very poorly preserved type that displays no discernibly distinctive characters’’ according to Vanzolini and Williams (1970: 85), who corrected the type locality and synonymized it under A. c. planiceps based on better preserved specimens from a nearby locality.

was not universally discarded and both it and nitens were continued as valid species in the Catalogue of the Neotropical Squamata (Peters and Donoso-Barros, 1970: 51, 61).

Thus the stage was set for Vanzolini and Williams to make order out of 140 years of confusion. In formulating their concept of Anolis chrysolepis (Duméril and Bibron, 1837) as a polytypic species, Vanzolini and Williams (1970: 83–86) considered the 13 specific names that were available (only four of which are mentioned above). The oldest name is Draconura nitens Wagler, 1830 , which they concluded ‘‘is probably, but hardly with certainty, applicable to some member of the chrysolepis group’’.

The type is lost, the type locality (‘‘America’’)

insufficiently defined, and the usage of the name

extremely confused, having been used primarily

for one of the color morphs possible to

chrysolepis group animals in Surinam (Boulen-

ger, 1885) or British Guiana ( Beebe, 1944) or

Venezuela (Shreve, 1947). Such a name could be

employed only arbitrarily, and we therefore set

it aside. (Vanzolini and Williams, 1970: 84)

Draconura nitens was viewed by Vanzolini and Williams (1970: 84) not as a verifiable senior synonym of chrysolepis but as a name of ‘‘uncertain application’’ (i.e., a nomen dubium). By this time, the 1837 name Anolis refulgens had become a nomen oblitum (a ‘‘forgotten name’’, rejected under Article 23b of the Code edition then in force; see also ICZN, 1999: 111 and art. 23.12). Because of that and as first revisers, Vanzolini and Williams (1970: 85) selected Anolis chrysolepis Duméril and Bibron (1837) as ‘‘the earliest satisfactory name for any member of the group’’, noting that it fortuitously was also the ‘‘most familiar name in the complex’’.

Hoogmoed (1973, 1979b) followed the nomenclature of Vanzolini and Williams, but thought that none of the reasons given

is sufficient to discard this name [ nitens ], for the

original description is completely valid and the

name has been in use until recently, alongside

the now accepted name A. chrysolepis Duméril

and Bibron which was more widely used

[emphasis added]. The only means of discarding

nitens Wagler and ensuring nomenclatural

stability is to ask the International Commission

on Zoological Nomenclature to use its plenary

powers to suppress nitens Wagler. A suggestion

to this end has been made by me to Vanzolini and Williams. ( Hoogmoed, 1973: 124)

Savage and Guyer (1989: 111–112) listed chrysolepis as a valid species of anole but considered nitens as a species ‘‘of uncertain generic assignment and questionably valid’’, seemingly in agreement with Vanzolini and Williams (1970: 84). However, two years later Savage and Guyer (1991: 366) decided that

nitens had over 125 years of continuous [albeit not prevailing] usage for this species prior to 1970’’ and that Vanzolini and Williams’ action in setting aside nitens was not only contrary to the Code in effect at that time (and currently), but required destabilization of a long-accepted name. (Savage and Guyer, 1991: 366)

Hoogmoed (1973) and Savage and Guyer (1991) believed that the synonymy of nitens and chrysolepis had been established by usage and that, under the Code then (and now) in effect, ‘‘the valid name of a taxon is the oldest available name applied to it’’ unless a junior name is preserved by the Commission. There is arguable merit in this interpretation. Literal reading of Article 23 in earlier editions (1961, 1985) of the Code might be interpreted to mean that, once applied, even an unidentifiable or erroneously applied subjective senior synonym not in prevailing usage must be maintained as valid under the Principle of Priority. But it seems questionable that such a consequence was originally intended by the Commission, which subsequently clarified the issue.

As a first underlying principle, the Code ( ICZN, 1985, p. xiii; 1999, p. xix) ‘‘refrains from infringing on taxonomic judgment, which must not be made subject to regulation or restraint’’, and the Commission elucidated this issue in the current edition (Article 23.3.6), whereby a junior synonym ‘‘may be used as the valid name of a taxon by an author who considers the synonymy to be erroneous’’.

Except for continuing to use Anolis over Norops, Ávila-Pires (1995) accepted Savage and Guyer’s suggestion that Anolis nitens corresponded to A. chrysolepis planiceps of Vanzolini and Williams. She stated that

Considering the argumentation by [Savage and Guyer], and the fact that up to the present no application was made to the International Commission on Zoological Nomenclature to suppress nitens , I think there is no reason not to adhere to the well-established rule of priority. Even considering that the type of nitens is lost, the name has been consistently linked to one taxon by several [emphasis added] authors, with no discrepancy between the taxon and the original description. Although some specimens from ‘‘Suriname’’ were identified as A. chrysolepis planiceps (see Hoogmoed, 1973) and A. nitens by some authors, generally the name nitens was associated with specimens from Guyana and Venezuela. This area corresponds to the distribution area of A. c. planiceps as used by Vanzolini & Williams (1970). Thus, in agreement with former usage and with the proposal of Savage & Guyer (1991), I consider the taxon occurring in Guyana and Venezuela as the nominal subspecies of Anolis nitens . (Ávila-Pires, 1995: 88)

However, problems are created in arbitrarily assigning the name nitens to a particular geographic area for purposes of fixing the nominotypical subspecies. The name nitens was used by 19th century authors for at least two species from ‘‘Surinamia [and] Brasilia’’ ( Fitzinger, 1843), from ‘‘Surinam’’ (e.g., Gray, 1845; Bocourt, 1874; Boulenger, 1885), and from Pebas on the upper Amazon (O’Shaughnessy, 1875: 277). Not until the 20th century was the name applied to specimens explicitly from Venezuela and Guyana (e.g., Fowler, 1913; Beebe, 1944). Selection of any area without neotype designation is equivalent to the unsanctioned concept of ‘‘restriction of type locality’’—the inventing or hypothesizing (versus justifiable correction) of a type locality that is not binding nomenclaturally and therefore without practical value (Myers and Böhme, 1996: 18).

Somewhat amazingly, only a few authors (Shreve, 1947; Vanzolini and Williams, 1970; Myers and Donnelly, 1997) appear to have been explicitly aware of the inadequacy of the original description of nitens . To illustrate this point, Wagler’s (1830: 149) complete description is given below, followed by an English translation.

DRACONURA . Drachenschweif.

Vertex et nares Dactyloae; gula plica longitudinali subinflabili; digiti prope articulationes subincrassati; cauda teres, basi incrassata, teretiuscula. (America.)

Species: Draconura nitens . Virescens supra, nitore cupreo-aureo, subtus albo-virens, argenteo-splendens; cauda tota aureo-viridi, maculis supra os sacrum duabus arcuatis obscuris; femoribus digitisque obsolete fasciatis.

DRACONURA . Dragon’s Tail.

Crown and nostrils of Dactyloa [the preceding genus]; with somewhat inflated longitudinal throat fold; digits somewhat thickened near articulations; tail smooth, thickened and a little rounded at the base. (America.)

Species: Draconura nitens . Green [see fn. 32] above, with a coppery gold sheen; below, whitish green with a silvery brilliance; tail totally golden green, with two bowlike dark spots above the sacral bone; thighs and digits weakly banded.

Without a specific type locality and without a known holotype, Anolis nitens can be identified only by the original description above. Furthermore, as stated by Vanzolini and Williams (1970: 84), nitens ‘‘could be assigned, if at all, only on the basis of color characters’’; the generalized morphology might exclude some taxa but does not provide species-specific characters. Therefore, Wagler’s portrayal of a brightly colored lizard must be assumed accurate—there is nothing else to go on and there are no objective grounds for concluding that some taxonomically critical item of coloration was omitted.

CHARACTERS CONSISTENT WITH A. CHRY- SOLEPIS: A conspicuous sheen is emphasized in the original description of nitens and in the name,30 suggestive of the metallic sheen seen in some anoles, including occasional specimens of chrysolepis (see below). The pair of dark sacral spots seems to be the only character really suggestive of the chrysolepis complex, but their presence is variable and they are not confined to A. chrysolepis . The indistinct thigh pattern seems relatively uninformative.

CHARACTERS INCONSISTENT WITH A. CHRYSOLEPIS : The fact that Wagler took the trouble to mention the sacral markings and the obsolete 31 thigh banding indicates that the animal was otherwise patternless. If

30 The specific name nitens is the present participle of Latin niteo and means ‘‘shining’’, ‘‘glittering’’, or ‘‘glossy’’.

31 This is a Latin adverb derived from obsoletus, meaning ‘‘rudimentary’’, ‘‘hard-to-see’’, or ‘‘scarcely apparent’’.

so, the absence of all head markings, tail banding, vertebral stripe or dorsal chevrons or rhomboids, lateral marbling, or other such pattern elements is inconsistent with what is known of the normal variation of Anolis chrysolepis . (An occasional old, poorly preserved and faded specimen of chrysolepis might conceivably lack describable pattern, but neither should such a specimen show the bright colors attributed to nitens .)

As previously stated (Myers and Donnelly, 1997: 59), the green dorsal coloring ascribed to nitens is inconsistent with Anolis chrysolepis , which is a variably patterned, basically brown or gray lizard. This requires additional elaboration.

‘‘GREEN’’ IN THE COLOR VARIATION OF ANOLIS CHRYSOLEPIS : Beebe (1944) indicated the great range of colors and color patterns of his composite A. chrysolepis / A. nitens at study sites in Venezuela and Guyana, including a specimen of chrysolepis having a general ground color of ‘‘olive with a strong greenish yellow tinge’’ and another one ‘‘grayish olive’’. A search of Myers’ field catalog reveals a few specimens having a slight greenish cast in the basic ground colors in life, including a ‘‘greenish gray’’ juvenile (EBRG 2902) and a ‘‘greenish gray’’ adult (AMNH R-140217) from Auyantepui and a ‘‘pale greenish brown’’ adult female from Cerro Guanay.

Such pale greenish casts, washes, or suffusions are not rare in the normal variation of brown or gray-colored reptiles and amphibians, but they disappear more quickly than normal greens in preservative and often are photographically elusive as well (e.g., Lynch and Myers, 1983: 522, 540). Nonetheless, under certain light, a pale bluish gray or pale greenish gray ground color can be seen on the lower sides or venters of some preserved Auyantepui specimens (AMNH R-140214–140217), although, in life, a greenish gray color was evident in only one of these (AMNH R-140217).

However, it is difficult imagining that anyone would describe such subtle hues as ‘‘green’’ without qualification.32 We earlier

32 Both English and Latin are rich in terms for shades of olive and greenish gray (e.g., olivaceous, olivaceoniger, olivaceo-griseus, viridi-olivaceous, viridi-griseus). The present participle virescens, used by Wagler for Draconura nitens , is one of several ‘‘more or less accurate’’ synonyms of viridis (green) fide Stearn (1983: 248). puzzled over the green in Wagler’s description:

Green coloring usually is lost quickly in lizards or snakes that are fixed in formalin prior to being stored in alcohol (a modern method of preservation). One might wonder whether the color green persisted longer in some of the spirits used for field preservation in Wagler’s time, or whether he knew that green often turns blue and was extrapolating from that color, or whether he had a color description from the collector. In any case, there is more than one way for an anole to be green and not all species change to blue in preservative (e.g., Myers, 1971: 11), which renders speculation rather pointless.

Therefore we cannot explain away the green coloring claimed in Wagler’s description …. (Myers and Donnelly, 1997: 59)

A slight metallic bronzy or golden sheen sometimes is evident in living A. chrysolepis (fig. 229 in Ávila-Pires [1995] seems to show this) and especially in preserved specimens. However, reasons for presence of a sheen, sometimes in association with a greenish hue, are not evident to us. Duméril and Bibron (1837: 91, 93–94) described the holotype of Anolis refulgens as having a ground color of ‘‘gris verdâtre doré [golden greenish gray, or ‘greyish…with metallic gloss’ as rendered by Boulenger, 1885: 92]’’ above and ‘‘blanche, glacée de verdâtre [white with a greenish glaze]’’ below, with dark head marbling, oblique bars, and crossbands on limbs and tail. Perusal of AMNH material revealed a specimen of A. chrysolepis scypheus (AMNH R-97359) having a tan ground color replaced by irregular areas of pale metallic blue-green on the posterior dorsum and left side, but oblique blackish brown lateral bars are well developed even in the blue-green area. The metallic shine in these few specimens is reminiscent of Wagler’s description of nitens , which, however, seems to have had a patternless body and tail.

SUMMARY COMMENTS ON ANOLIS NI- TENS: No author has argued that Wagler’s (1830) description of nitens demonstrably applies to chrysolepis , only that the name has priority and has been applied to that species. However, despite perceived shortcomings of Wagler’s description, his portrayal of color is so vivid that the name nitens probably could be assigned if a virtually patternless, green lizard were found matching the description—but would the hypothetical animal prove to be a rare color-pattern variant of a known species (e.g., A. chrysolepis ) or a representative of a rare or geographically restricted species not currently recognized (i.e., A. nitens sensu stricto)?

The name nitens is a nomen dubium that cannot unambiguously be assigned to any known lizard. Article 23.3.6 allows authors who reject the synonymy to use the junior name chrysolepis as valid. However, although never in prevailing usage historically, nitens remains in competing use with chrysolepis because of prior (and arguable) interpretation of Article 23.

Until Ávila-Pires (1995), the body of work comprising the continuous usage of nitens was not impressive, inasmuch as the name had been mentioned mostly in lists and had been applied in print only to a few dozen specimens by 1970, compared with 761 specimens later assigned by Vanzolini and Williams (1970: 13) to the better known name chrysolepis . Studies using the name nitens subsequent to Ávila-Pires (1995) include Gorzula and Señaris (1999), Glor et al. (2001), and McDiarmid and Donnelly (2005).

Because of the confusion that has been engendered, we now agree with Hoogmoed (1973) that stability will best be served by petitioning the International Commission on Zoological Nomenclature to suppress nitens . A proposal for suppression was submitted by the first author in December 2007. Meanwhile we use the name Anolis chrysolepis as allowed by Article 23.3.6 ( ICZN, 1999).