Drymoluber dichrous Peters 1863

Drymoluber dichrous (Peters, 1863) Herpetodryas dichroa Peters, 1863. Monatsberichte der königlich Akademie der Wissenschaften zu Berlin, 29, p. 284. Syntypes: ZMB 1661, ZMB 1662, ZMB 2603. Herpetodryas occipitalis Günther, 1868. Annals and Magazine of Natural History, Fourth Series, 1, p. 420. Holotype: BMNH 1946.1. 14.61, formerly 1867.9. 17.28. Spilotes piceus Cope, 1868. Proceedings of the Academy of Natural Sciences of Philadelphia, 20, p. 105–106. Holotype: ANSP 3920. Coluber dichrous— Boulenger, 1894. Catalogue of the Snakes in the British Museum (Natural History). Volume II. British Museum of Natural History, London, p. 30–31. Elaphe dichrous— Gomes, 1918. Memórias do Instituto Butantan, 1, p. 67. Drymoluber dichrous— Amaral, 1930. Memórias do Instituto Butantan, 4, p. 337. Lectotype (here designated in accordance with Article 74 of the International Code of Zoological Nomenclature): Museum für Naturkunde Berlin ZMB 1661, adult of undetermined sex (probably a male), SVL 585 mm, TL 242 mm, collected in Brazil during the first half of the 19 th century by Georg Wilhelm Freyreiss. Specimen examined by photographs. Although we do not know specifically where specimen ZMB 1661 was collected, the itinerary of its collector is known, and this information leads us to designate it as the lectotype, instead of the syntype ZMB 2603, which was listed as “probably from Suriname ” or ZMB 1662 which has a broken tail. Paralectotypes: Museum für Naturkunde Berlin ZMB 1662, adult of undetermined sex, SVL 568 mm, TL 237 +N mm (broken tail), collected in Brazil during the first half of the 19 th century by Georg Wilhelm Freyreiss; ZMB 2603, adult of undetermined sex (probably a female), SVL 623 mm, TL 225 +N mm (broken tail), supposedly bought in Suriname. This same information about the collection site of ZMB 2603 is recorded in the catalogue of the Museum für Naturkunde Berlin and on the oldest label of the specimen. However, a newer label (with the name Drymoluber dichrous) indicates “ Brasilien Becker ”. The reason and source for the adjusted locality is unknown even to the current curator (M. O. Rödel, pers. com.). We examined the specimens from photographs. About the type locality: There is no information about the dates of collection, shipment to Europe or arrival at the Museum für Naturkunde Berlin of the type series of D. dichrous (M. O. Rödel, pers. com.). Thus, the type locality of D. dichrous was reported as “ Brazil and Surinam ” (e.g. Peters & Orejas-Miranda 1970). Since the lectotype designated above (ZMB 1661) is the new name-bearing type of D. dichrous, its place of collection is the type locality. Despite the lack of detailed information as to where the specimen was collected, we consider the type locality to be the area traveled by its collector, G.W. Freyreiss, in Brazil (Fig. 13 and text below). Freyreiss was born in Frankfurt on 12 July 1789. In 1813 he left St. Petersburg bound for Brazil, starting his expeditions in June 1814. He departed from the province (currently state) of Rio de Janeiro and travelled south to Minas Gerais, along the Caminho do Proença, a path of the ancient royal road to Vila Rica (currently the municipality of Ouro Preto) (Freyreiss 1907; Papavero 1971) (Fig. 13, localities 1–12). In September 1814, Freyreiss explored the region around the Abaeté, Indaiá and São Francisco Rivers, later returning to Vila Rica (Freyreiss 1907; Papavero 1971) (Fig. 13, localities 12–18 – 12). In December 1814 he began a second trip to study Indian tribes, travelling from Vila Rica to the vicinities of Presídio São João Batista (currently the municipality of Visconde do Rio Branco) (Fig. 13, localities 12–23). Later he returned to Vila Rica, and then (January 1815) to Rio de Janeiro, leaving no records of his path in this part of the voyage (Freyreiss 1907; Papavero 1971). In July 1815, Maximilian Alexander Philipp, prince of Wied-Neuwied (also known just as Wied) arrived in Brazil, and in August began a natural history trip together with Freyreiss and Friedrich Sellow (Wied 1989; Papavero 1971). From the city of Rio de Janeiro they headed north to Espírito Santo and Bahia provinces (Wied 1989; Papavero 1971). In February 1816, the naturalists were in the Mucuri River, southern Bahia (Fig. 13, localities 1, 24– 37). There, Freyreiss decided to return to Espírito Santo, while Wied continued his travel northward (Wied 1989, p. 186). In Espírito Santo, Freyreiss visited again the localities of São Mateus and Linhares (Fig. 13, localities 35 and 36), and in May 1816 he travelled back to Mucuri (Fig. 13, locality 37) to visit Wied (Wied 1989, p. 162, 170, 201). While Freyreiss and Sellow stayed in Mucuri, Wied continued travelling toward the north. In Ocotber 1816, Wied returned to Mucuri to visit Freyreiss and Sellow, with whom he spent three weeks before heading north again (Wied 1989, p. 273). There is no itinerary of the voyages of Freyreiss after that, but it is known that in Bahia he also visited the localities of Caravelas, Canavieiras (Wied 1989, p. 330) and Salvador (Fig. 13, localities 39, 40 and 41), and contributed to the foundation of a German colony, Colônia Leopoldina, currently part of the municipality of Nova Viçosa (Papavero 1971) (Fig. 13, locality 38). There are some inconsistencies related to the place of death of Freyreiss, in 1825. Löfgren (1902) and Papavero (1971) wrote that the German naturalist died in Colônia Leopoldina, while Rocha (1972 “ 1973 ”) stated that he died in Europe. Wied described the species collected during his travels, and his collections are now in the American Museum of Natural History. Even though the type series of D. dichrous is in Germany, we believe that if Freyreiss collected the specimens of D. dichrous during the trip from Rio de Janeiro to Bahia, it probably was done at times when he was not with Wied’s expedition. It is known that from his trips through Espírito Santo and Bahia, Freyreiss sent three shipments of collected specimens to Europe (Papavero, 1971), but, as we have written above, there is no information about the dates when the type series of D. dichrous was collected, shipped to, or arrived in Europe. Additionally, we have record of a single shipment of specimens sent to Europe from his trip through Minas Gerais, when he stated that his collections were sent to Rio de Janeiro on 30 July 1814 (Freyreiss 1907, p. 167). As his travels continued, he certainly made other shipments, of which we have no information. Diagnosis: Drymoluber dichrous is distinguished from D. brazili and D. apurimacensis by the following combination of characters: a) 15 - 15 - 15 dorsal scale rows with two apical pits; b) 157–173 ventrals in males, 160– 180 in females; c) 87–110 subcaudals in males, 86–109 in females; d) 19–26 maxillary teeth. See Table 5. Comparisons: Drymoluber brazili has 17 - 17 - 15 dorsal scales rows, and D. apurimacensis has 13 - 13 - 13. Apical pits are absent in D. apurimacensis. Drymoluber brazili has 182–200 ventrals in males and 185–202 in females, 109–127 subcaudals in males and 109–126 in females. Drymoluber apurimacensis is not distinguishable from D. dichrous based on ventrals and subcaudals counts, having 158–164 ventrals in males and 166–182 in females, 84–93 subcaudals in males and 87–91 in females. Drymoluber apurimacensis has 14–16 maxillary teeth. Small specimens of D. dichrous have dark crossbands 1.5–7 scales wide (mean 3.6) and light interspaces 0.5– 2.5 scales wide (mean 0.8), while in D. apurimacensis the dark crossbands are 1–2 scales wide, and the pale interspaces are 2–3 scales wide. Juvenile specimens of D. brazili have dark crossbands of similar width to those of D. dichrous (2–6 scales; mean 3.6), but the pale interspaces are wider (0.5–5 scales; mean 1.6). The hemipenes of D. dichrous tend to have more calyces than D. brazili, smaller spinulated flounces, and no spines in the lobular region. The walls of the sulcus spermaticus tend to have more ornamentation, at least in the lobular region, with small jagged papillae. The spines of the asulcate face are generally larger than those of D. brazili, especially those most proximal. The hemipenial morphology of D. dichrous and D. apurimacensis is similar and of little value in differentiating these species. Description of the lectotype (Fig. 14): Snout-vent length 585 mm, and tail length 242 mm; head distinct from the body, 24.6 mm length (4.2 % of the SVL); greatest width of head 12.9 mm (52 % of its length); width of head at the supraoculars 9.3 mm; internasal distance 5.1 mm; eye diameter 4.45 mm; eye-nostril distance 4.5 mm. The morphometric measurements were taken by Christoph Kucharzewski, Museum für Naturkunde Berlin. Smooth dorsal scales in 15 - 15 - 15 rows, with two apical pits; 161 ventrals and 1 preventral (sensu Peters 1964); cloacal shield entire; tail intact, with 96 divided subcaudals and one terminal spine; rostral wider than high, visible from above; internasals and prefrontals slightly wider than long; each prefrontal contacting the frontal, supraocular, internasals, posterior nasal, preocular and loreal; frontal about 1.5 times longer than wide; supraoculars longer than wide; parietals about 1.5 times longer than wide; nasal divided above and below the naris, mainly in contact with the first supralabial, but also with the second; loreal slightly longer than high, contacting the second and third supralabials; one preocular; two subequal postoculars; three anterior temporals (one upper and two lower) and two posterior temporals (one upper and one lower) on the right side (1 / 2 + 1 / 1); four anterior temporals (two uppers and two lowers) and two posterior temporals (one upper and one lower) on the left side (2 / 2 + 1 / 1); eight supralabials, the fourth and the fifth contacting the eye; mental triangular, wider than long; nine infralabials, the first pair in contact behind the mental; first to fifth infralabials in contact with the first pair of chinshields; fifth and sixth infralabials in contact with the second pair of chinshields; sixth to ninth infralabials contacting the gulars; first pair of chinshields about the half of the length of the second. FIGURE 13. Itinerary of the travels made by Georg Wilhelm Freyreiss in Brazil, in the 19 th century, when the lectotype (ZMB 1661) and one paralectotype (ZMB 1662) of Drymoluber dichrous were collected. The inset map shows South America, highlighting in gray the current states of Rio de Janeiro (RJ), Espírito Santo (ES), Minas Gerais (MG) and Bahia (BA), visited by Freyreiss. For easy viewing, only the main localities are represented in the main map. For complete lists of localities, see Freyreiss (1907) and Wied (1989), Bokermann (1957) and Papavero (1971). When the old and current names of a toponym are different, the later is written inside brackets. 1 = Praia dos Mineiros, Rio de Janeiro; 2 = Porto Estrela (Magé); 3 = Fazenda Mandioca (Magé); 4 = Fazenda do Padre Correia (Corrêas, Petrópolis); 5 = Fazenda das Sebollas (Inconfidência, Paraíba do Sul); 6 = Rio Paraibuna; 7 = Matias Barbosa; 8 = Juiz de Fora; 9 = Chapéu D’Uvas (Juiz de Fora); 10 = Barbacena; 11 = Congonhas do Campo (Congonhas); 12 = Villa Rica (Ouro Preto); 13 = Ponte das Almoreiras (Ponte das Almorreimas, Brumadinho); 14 = Fazenda São Joanico (Maravilhas); 15 = Pompeu; 16 = Rio São Francisco; 17 = Fazenda do Comandante de Indaiá (Quartel Geral); 18 = Quartel do Assunção (Córrego dos Tiros, Tiros); 19 = Mariana; 20 = Santana dos Ferros (Guaraciaba); 21 = Santa Rita (Viçosa); 22 = Serra de S. Beralde (Serra de São Geraldo, São Geraldo); 23 = Presídio de São João Batista (Visconde do Rio Branco); 24 = S. Gonzalves (São Gonçalo); 25 = Freguesia de Maricá (Maricá); 26 = Araruama; 27 = Cabo Frio; 28 = Villa de S. João de Macahé (Macaé); 29 = Villa de S. Salvador dos Campos dos Goytacazes (Campos dos Goytacazes); 30 = Itapemerim; 31 = Povoação de Piuma (Piúma); 32 = Nossa Senhora da Victoria (Vitória); 33 = Vila Nova do Almeida (Nova Almeida, Serra); 34 = Quartel do Riacho (Riacho, Aracruz); 35 = Linhares; 36 = Barra do São Mateus (São Mateus); 37 = Rio Mucuri (Mucuri); 38 = Colônia Leopoldina (Nova Viçosa); 39 = Caravelas; 40 = Canavieiras; 41 = Salvador. Dashed line = Travel from Rio de Janeiro to Quartel do Assunção (Tiros), in 1814 (Localities 1 –12, 12–11, 11– 18); Dotted line = Travel from Villa Rica (Ouro Preto) to the vicinities of Presídio São João Batista (Visconde do Rio Branco), from December 1814 to January 1815 (Localities 12–23); Dashed-dotted line = Travel from Rio de Janeiro to Mucuri, from July 1815 to 1816 (Localities 1, 24– 38). Localities 39–41 are not linked by lines because of the lack of information about the itinerary took by Freyreiss when visiting them. Tropical and subtropical moist forests; Tropical and subtropical savannas; Deserts and xeric formations; Mangroves; Tropical and subtropical dry forests. Habitat types follow Olson et al. (2001). Coloration of the lectotype: Peters (1863) described the coloration of Herpetodryas dichroa as: “Dorsum olive-brown, the sides, including the lateral edges of ventral plates; subcaudals olive-green; the whole venter to the tip of the tail of yellow color; a black stripe bordered by the yellow (darker than that of the belly) supralabials on both sides of the head, becoming suddenly wider behind the eyes.”. After almost 200 years of preservation, the dorsum is uniformly brownish-blue. Supralabials, gular region and venter are uniformly creamish colored, the lateral edges of ventrals and subcaudals are the same color as the dorsum. The upper margins of some supralabials, especially the last two, have the color of the dorsum. The dark lateral stripe of the head is indistinct. Coloration of preserved adults: The dorsal coloration of adult specimens after fixation is usually darker than the lectotype, with bluish-gray or dark-blue colors. Faint crossbands that formed the juvenile color pattern are visible in smaller specimens. The venter of most specimens is immaculate cream, with lateral edges of ventral plates having the same color as the dorsal scales (n= 203; 95 %). In some cases (n= 3; 1.5 %) the dark dorsal coloration continues into the ventral region from the lateral edges of ventral plates. There are specimens with a creamish venter with small black marks (n= 3; 1.5 %). The venter of some specimens is the same color as dorsal scales or a little paler (n= 3; 1.5 %). One specimen (0.05 %) has a yellow venter, with the lateral and the posterior edges of ventral plates darkened. The ventral part of the tail usually is creamish with lateral edges of subcaudals darkened (n= 207; 97 %), with little variation. The lateral edges may not be darkened (n= 1; 0.05 %), the subcaudals may have small black dots, in larger numbers in the posterior region (n= 1; 0.05 %), or be completely black along the whole tail (n= 4; 2 %). The gular region is pale and immaculate in most specimens (n= 153; 72 %). Some of them, however, have dark marks in the posterior edges of infralabials, and sometimes on the chinshields (n= 60; 28 %). The lateral edges of supralabials (especially the last ones) in most specimens are dark colored (n= 166; 78 %), sometimes (n= 14; 6.5 %), with strong and thick marks. Supralabials can also be completely dark (n= 15; 7 %) or totally cream, without marks, or with inconspicuous marks (n= 18; 8.5 %). Coloration of adults in life: Based on descriptions in the literature (e.g. Cunha & Nascimento 1978; Martins & Oliveira 1998; Bartlett & Bartlett 2003; Argôlo 2004 a) and some photographs (Fig. 15), we noted some variation in the color pattern of adult specimens of D. dichrous in life—but unrelated to the geographic distribution. The dorsum varies between brown, olive-brown, green, dark-green and gray-bluish. In some snakes the dorsal color changes posterior to the first third or the half of the body. The dorsum of head is sometimes a little paler than the body. A barely distinguishable black stripe from the preocular to the end of the posterior temporal may be present. Supralabials, gular region and the venter vary between yellow and white, with the lateral edges of ventrals and subcaudals of the same color or little paler than the dorsals. The supralabials also may be dark along their upper and lateral edges. Coloration of preserved juveniles: The number of dark crossbands along the body varies between 31 and 52 (mean 40; SD= 4.3; n= 49; 63 %). Specimens with indistinct bands on the posterior third of the body are common (n= 29; 37 %), and in seven small specimens (SVL 285–391 mm), the banded coloration has disappeared completely. The tail bands are rarely visible (only in some specimens with SVL