Cyclopes didactylus, (LINNAEUS, 1758)

Miranda, Flávia R., Casali, Daniel M., Perini, Fernando A., Machado, Fabio A. & Santos, Fabrício R., 2018, Taxonomic review of the genus Cyclopes Gray, 1821 (Xenarthra: Pilosa), with the revalidation and description of new species, Zoological Journal of the Linnean Society 183, pp. 687-721 : 700-704

CYCLOPES DIDACTYLUS ( LINNAEUS, 1758)

( FIG. 10)

[ Myrmecophaga ] didactyla Linnaeus, 1758: 35 . Type locality ‘America australi’, restricted to Suriname by Thomas (1911).

Mirmecophaga dydactyla Brongniart, 1792: 115 . Incorrect subsequent spelling of didactyla Linnaeus, 1758 .

Myrmecophaga monodactyla Kerr, 1792: 105 . Type locality unknown.

Myrmecophaga unicolor Desmarest, 1822: 375 , footnote. Type locality unknown. Name attributed to É. Geoffroy St.-Hilaire.

Eurypterna didactyla : Gloger, 1841: 112. Name combination.

Cyclothurus didactyla : Lesson, 1842: 152. Name combination.

Cyclothurus fulvus Macalister, 1875: 492 . Nomen nudum.

Mamcyclothurus didactylos Herrera, 1899: 19. Unavailable name ( Gardner 2007).

C [yclopes]. didactylus : Thomas, 1900 d: 302. First use of current name combination.

Cyclopes didactylus melini Lönnberg, 1928: 15 . Type locality ‘ S. Gabriel, Rio Negro’ , Amazonas, Brazil.

Cyclopes pygmaeus Cameron, 1939: 249 . Nomen nudum.

Holotype: As is usual for many species described by Linnaeus, C. didactylus lacks a holotype specimen. It is generally agreed that Linnaeus (1758) based his description on a plate by Albertus Seba (1734 –1765), although a specimen of the Museum Adolphi Frederici, described in a published catalogue of the Sweden King’s collection, is also referred to (see below). All material in this collection has been transferred to the Naturhistoriska riksmuseet ( NRM) in Stockholm, Sweden. An analysis of the skins and skulls of NRM did not locate the referred specimen. Therefore, no name-bearing type specimen is currently known for this species. The type locality assigned by Linnaeus (1758) was America australi (South America), but Thomas (1911) restricted it to Suriname. Therefore, we selected a specimen from this locality and designate it a neotype for C. didactylus , in accordance with Article 75 of the International Code of Zoological Nomenclature ( ICZN, 1999).

Neotype and type locality: Stuffed skin and skull of an adult female, housed at the Field Museum of Natural History , in Chicago, catalogue number 93175, collected by Harry A. Beatty in 29 September 1960, at the Kayser-Gebergte Airstrip, Suriname ( Figs 11, 26).

Referred specimens: Neotype: FMNH (993175), Suriname; Brazil: MNRJ (17294), Maceió, Alagoas, MZUSP (7523, 19942), Manimbu, Alagoas; MNRJ (17295), Rio São Francisco, Alagoas; MNRJ (17293), Viçosa, Alagoas; MNRJ (20593), Ilha do Brigue, Amapá; MZUSP (4679, 4699, 19933), Itacoatiara, Amazonas; MZUSP (7120), Lago do Batista , Amazonas; FMNH (34248, 34249), Manaus, Amazonas; INPA (191, 4075), Manaus, Amazonas; MPEG (1481), Santa Izabel do Rio Negro (left margin of Rio Negro ), MZUSP (3176, 3177, 3178), Humberto de Campos , Maranhão; MNRJ (2351, 2352, 2354), Abaeté, Pará; MNRJ (2350), Araguaia River , Pará; AMNH (96470, 96471), Baiao, Pará; MVZ (121210), Belém, Pará; AMHN (37474, 203377), Belém, Pará; MPEG (425, 427, 2333, 2410), Belém, Pará; MZUSP (8680, 8681, 24137), Belém, Pará; MZUSP (4696), Bravo, Pará; AMHN (96444, 96445, 96446, 96448, 96449, 96450, 96451, 96452, 96453, 96454, 96455, 96456, 96457, 96458, 96459, 96460, 96461, 96462, 96463, 96464, 96465, 96466, 96467), Cametá, Pará; FMNH (50907), Cametá, Pará; MNRJ (2349, 5966), Cametá, Pará; MPEG (33940, 33941), Cametá, Pará; MZUSP (4675, 4676, 4677, 4678, 4680, 4681, 4682, 4683, 4684, 4685, 4686, 4687, 4689, 4690, 4691, 4692, 4693, 4694, 4695, 4697, 4698, 4701, 4702, 4703, 19932), Cametá, Pará; MPEG (2335), Castanhal, Pará; AMHN (95506), Igarapé do Amorim , Pará; FMNH (24796, 34247), Ilha das Onças , Pará; MNRJ (2345), Ilha das Onças , Pará; AMHN (133505), Ilha de Marajó , Pará; MNRJ (4910), Ilha de Marajó , Pará; MNRJ (2347), Ilha do Mosqueiro ; MPEG (38374), Jurití, Pará; AMNH (96468, 96469), Macajuba, Pará; MPEG (38181), Marabá, Pará; MPEG (716, 1190), Marambaia, Pará; MNRJ (23968), Santarém, Pará; MPEG (1955), Tomé-Açu, Pará; INPA (393), Trombetas, Pará; MPEG (12406), Tucuruí, Pará; FMNH (19500), Pará; MNRJ (2346, 2348), Pará; USMN (545910), Pará; MZUSP (8451), Mamanguape, Paraíba; French Guiana: FMNH (21719), Cayenne; AMNH (1998, 48388); Suriname: FMNH (993175), Zuid River ; Trinidad and Tobago: AMNH (30744), Aripo; AMNH (186442), Cumana; AMNH (130107); AMNH (174172, 174173, 174183), Ilha de Maingot ; FMNH (61853, 61854); USNM (102083, 270995); Venezuela: USNM (406494), Acanana; AMNH (77354, 77355), Atabato; AMNH (16129), Bolivar; USNM (296611, 296612), Caicara; AMNH (77356), Esmeralda; USNM (282157), Monagas; AMNH (16956, 16957), Raul Leoni; USNM (143740, 143741), Suapure.

Distribution: Cyclopes didactylus appears to have a disjunct distribution in South America. It occurs in the northern Amazon Forest, left margin of Negro, Uaupés and at both sides of Orinoco Rivers, towards northern Venezuela, and the Guianas, including also the island of Trinidad. It also occurs on the right side of the Amazon River, in northeastern Amazon of Brazil (Pará State) towards the Brazilian states of Maranhão and Piauí, with a disjunct population in the northeastern Atlantic Forest, including the states of Rio Grande do Norte, Paraíba, Pernambuco and Alagoas ( Fig. 27).

Diagnosis: General colour brownish-yellow in dorsal and ventral views, rump, legs and tail grey. Dorsal stripe irregular, but distinctive, dorsal and ventral black stripes evident. Fronto-nasal region of the skull is depressed, with a concave profile. External aperture of the ear directed anteriorly. Naso-maxillary sutures divergent proximally, with very short fronto-maxillary suture. Fronto-parietal suture with trapezoidal shape and pterygoid bone partially overlaps tympanic bulla.

Comparisons: Cyclopes didactylus is the only Cyclopes species with both dorsal and ventral dark stripes clearly marked. Cyclopes xinguensis sp.nov. also have both stripes, but the ventral stripe is faint and irregular. Besides, the coloration of C. xinguensis is greyish, in contrast with the yellowish tone of the dorsum and grey limbs of C. didactylus . However, some populations of C. didactylus may have an indistinct ventral stripe or lack it entirely (see below), which is similar to C. dorsalis . However, the dorsal stripe of C. dorsalis is paler, and the body coloration is more brightly yellow than C. didactylus .

Remarks: The species was described by Linnaeus (1758) as Myrmecophaga didactyla , described as ‘ M[anibus]. palmis didactylis, palmis tetradactylis ’, referring to the two digits on the manus and four on the pes. Linnaeus based his description on a plate by Albertus Seba (1734 –1765: pl.XXXVII, fig. 3) ( Fig. 12). Linnaeus also refers to a specimen of the Museum Adolphi Frederici, described in a published catalogue of the Sweden King’s collection as:

{Magnitudo Sciuri aut Felis minoris. Color griseus . Aures parvae. Pedes omnes, ursi instar,

talis incedentes. Palmis unguibus duobus exteriore duplo majore. Plantis unguibus quat-

uor aequalibus, digitis coadunatis. Cauda longitudine fere corporis, pilis brevibus, ut corpus, vestita, non vero vulpina aut pilosa}.

The type locality assigned by Linnaeus was America australi (South America), but Thomas (1911) restricted it to Suriname, based on the description of Seba’s plate, and since he usually received his material from Suriname, it is considered a plausible origin for the specimen that is illustrated in the Thesaurus. Oldfield Thomas also pointed out that Linnaeus’ description was based on the specimen at the Adolphi Frederici Museum, referring to the previously mentioned catalogue.

Following Linnaeus tenth edition of Systema Naturae (1758), the name Myrmecophaga didactyla is recognized as the first valid species name for C. didactylus . Brongniart (1792) misspelled it as Myrmecophaga dydactyla . In the same year, Kerr (1792) discussed differences between the drawings of Buffon (1763: pl. XXX) and Thomas Pennant (1793: pl. XCV) in respect of the number of toes on the manus of Myrmecophaga didactyla : the former depicted the animal with a single claw and the latter with two. Although Kerr (1792) states that he could not elucidate the reason for this difference and that the drawing of Buffon could represent a mutilated dry skin, he suggests the possibility of the existence of a second species and that it would deserve the name Myrmecophaga monodactyla . However, Buffon’s illustrations clearly refer to a two-clawed specimen, as depicted in plate XXXII and, specially, in plate XXXIII ( Buffon, 1763), where the limb skeletons of Myrmecophaga didactyla are depicted, clearly showing two digits ( Fig. 13A–C).

Desmarest (1822), in a footnote, attributes to É. Geoffroy Saint-Hilaire the name Myrmecophaga unicolor , while specifically mentioning the presence of a dorsal stripe in Myrmecophaga didactyla . According to Desmarest, É. Geoffroy Saint-Hilaire considered specimens that lack the dorsal band to be a different species. No specific citation was provided to confirm this assertion. Myrmecophaga unicolor is mentioned in some later works, such as in Lesson (1827), where it is postulated that in Cayenne ( French Guiana) the stripeless variety is considered the female of Myrmecophaga didactyla , and in Smith (1827), where the name is attributed to a manuscript (possibly meaning unpublished) by É. Geoffroy.

Different name combinations, such as Myrmecolichnus didactylus ( Reichenbach, 1836) , Eurypterna didactyla ( Gloger, 1841) and Cyclothurus didactyla ( Lesson, 1842) , were proposed, but always referred to the type originally described by Linnaeus (1758). Oldfield Thomas (1900) was the first to use the current name combination, Cyclopes didactylus , while describing a new subspecies. Macalister (1875) mentions the dissection of a Cyclothurus fulvus , which he compares with Cyclothurus didactylus , but without further elaboration. The name itself does not appear anywhere else in the literature and is thus considered a nomen nudum. Cameron (1939), in a study about parasites from Trinidad, mentions the name of the species Cyclopes pygmaeus , even stating that C. didactylus would be synonymous, but no further comments are made. It is also considered here a nomen nudum.

In 1928, Lönnberg described the subspecies C. didactylus melini , with the holotype from São Gabriel da Cachoeira, Rio Negro, Brazilian Amazon. The description provided and the holotype conforms well with C. didactylus , with the yellowish body, grey limbs and dorsal stripe. However, the specimen lacks a ventral stripe. Given that other characters, including characters from the skull, agree more with a C. didactylus identity, we consider C. didactylus melini as synonymous with C. didactylus . Other specimens here attributed to C. didactylus also have an indistinct or absent ventral stripe (Supporting Information, File 33); therefore, its absence is attributed to a variation within the species, pending further data.