Dendrophidion graciliverpa CADLE, 2012
Can you confirm these amateur observations of Dendrophidion graciliverpa?
|Higher Taxa||Colubridae, Colubrinae, Colubroidea, Caenophidia, Alethinophidia, Serpentes, Squamata (snakes)|
|Synonym||Dendrophidion graciliverpa CADLE 2012|
Drymobius dendrophis — BOULENGER 1894: 16 (part)
Dendrophidion percarinatum — DUNN 1944: 477 (part)
Dendrophidion graciliverpa — WALLACH et al. 2014: 225
Type locality: 3 km E Pasaje, 30 m elevation, El Oro province, Ecuador [03°20’S, 79°49’W].
|Types||Holotype: AMNH 110584 (Figs. 20, 21, 23, 26A in Cadle 2012).|
|Diagnosis||Diagnosis. Dendrophidion graciliverpa is characterized by (1) dorsocaudal reduction from 8 to 6 occurring anterior to subcaudal 28 (range, 7–27); (2) divided anal plate; (3) subcaudal counts >=120 in males and females; (4) subadults with narrow pale bands (<1 dorsal scale width on the neck) or transverse rows of ocelli; adults retain bands or become predominantly brown or green (pale bands usually separated by fewer than three dorsal scale rows on the neck; total number of pale bands on the body >55); (5) ventrals immaculate or with narrow trans- verse dark lines across the anterior border of each ventral plate; (6) in life, head greenish brown to green and body brownish, olive, or grayish; and (7) everted hemipenis of the ‘‘gracile’’ morphology, with an exceptionally long, slender hemipenial body proximal to an expanded distal portion, which bears spines, calyces, and other apical ornamentation (retracted hemipenis nearly always to sub- caudal 10 or greater); total number of enlarged spines on hemipenis >80 (81, 84, and 116 in three studied organs).|
‘‘Gracile’’ hemipenial morphology will distinguish D. graciliverpa from all other species of Dendrophidion except D. prolixum described herein and perhaps D. bivittatum (see above comments where the gracile morphology is described). Dendro- phidion bivittatum has a different color pattern (greenish dorsum with blackish longitudinal stripes).
Dendrophidion graciliverpa differs from species of the D. dendrophis species group (D. dendrophis, D. atlantica, D. nuchale auctorum, D. apharocybe, D. crybelum, D. vinitor) in having a reduction in the dorsocaudal scales anterior to subcaudal 30 (posterior to subcaudal 30 in the D. dendrophis group except occasional females). A divided anal plate will distinguish it from D. apharocybe, D. crybelum, and D. vinitor (anal plate nearly always single in these species). Dendrophidion dendrophis and D. nuchale auctorum may have either single or divided anal plates but have different color patterns (see Duellman, 1978: 236–237, 2005: pl. 175; Savage, 2002: 654, pls. 413–415), attain greater body sizes, and have different hemipenial morphologies (robust morphology and enormously enlarged spines in D. dendrophis and D. nuchale). Dendrophidion graciliverpa differs from D. boshelli in having 17 midbody scale rows (15 in D. boshelli).
Dendrophidion graciliverpa has previous- ly been confused with D. percarinatum, and these species cannot be distinguished by traditional scutellation features other than a few mean character differences (Table 1). These two species differ in (1) color pattern: greenish head and anterior body, and venter either immaculate or with dark transverse lines (D. graciliverpa) vs. head and body primarily browns to grays, and venter immaculate (D. percarinatum); (2) hemi- penial morphology: gracile (graciliverpa) vs. robust (percarinatum); retracted hemipenis nearly always to subcaudal 10 or greater (D. graciliverpa) vs. ,10 subcaudals (D. percarinatum); total number of enlarged spines on the hemipenis .80 (D. graciliverpa) vs. fewer than 45 (D. percarinatum); (3) relationship between the posterior suprala- bials and temporals as discussed above: G pattern most commonly (D. graciliverpa) vs. P pattern most commonly (D. percarinatum). Dendrophidion graciliverpa has a greater number of pale bands on the body and different overall coloration than D. prolixum (see account for the last species and Table 4 for details) [from CADLE 2012].
|Comment||Distribution: (Fig. 27 in Cadle 2012) Dendrophidion graciliverpa occurs in the lowlands of western Ecuador from Esmeraldas and Imbabura provinces in the north to Loja province in the south. The upper elevational record, 1,750 m, is based on a juvenile male and female from Cotopaxi province (MCZ 163968–69, referred specimens). These specimens have typical graciliverpa banding patterns, and the retracted hemipenis of the male extends to the proximal suture of subcaudal 15 (potential confusion with D. brunneum is possible in this area, but gracile hemipenial morphology is decisive for identification).|
Habitat: partly arboreal (Harrington et al. 2018).
|Etymology||The specific name is a feminine noun in apposition derived from the Latin words gracilis (slender or gracile) + verpa (penis). The name refers to the long, slender hemipenis of this species in comparison specifically to Dendrophidion percarinatum, with which it has been confused, but also more generally to hemipenes of most other species of Dendrophidion.|