Hemiancistrus subviridis, Werneke & Sabaj & Lujan & Armbruster, 2005

Werneke, David C., Sabaj, Mark H., Lujan, Nathan K. & Armbruster, Jonathan W., 2005, Baryancistrus demantoides and Hemiancistrus subviridis, two new uniquely colored species of catfishes from Venezuela (Siluriformes: Loricariidae), Neotropical Ichthyology 3 (4), pp. 533-542: 538-541

publication ID

http://doi.org/ 10.1590/S1679-62252005000400011

publication LSID

lsid:zoobank.org:pub:71C4BB92-E049-4145-BBD6-08D71B190961

persistent identifier

http://treatment.plazi.org/id/51F7380B-0B73-4DF3-9E0C-8E4E0C4EEFAA

taxon LSID

lsid:zoobank.org:act:51F7380B-0B73-4DF3-9E0C-8E4E0C4EEFAA

treatment provided by

Carolina

scientific name

Hemiancistrus subviridis
status

new species

Hemiancistrus subviridis   , new species

Figs. 1c View Fig and 4 View Fig

Holotype. MCNG 54032, 133.5 mm SL, Venezuela, Amazonas, río Orinoco 117 km W of La Esmeralda, 03.28998°, -066.60004°, 29 Mar 2005, N. K. Lujan, M. Arce, T. E. Wesley, M. B. Grant, E. L. Richmond, J. Valadez, D. Brooks, F. Brito, & O. Santaella   . Paratypes. VENEZUELA, Amazonas, río Orinoco drainage: ANSP 162167 View Materials , 1 View Materials (1, 149.5 mm SL), río Orinoco at rocks 1 km above La Esmeralda, 14 Mar 1987, W. G. Saul, J. Fernandez, O. Castillo, & M. E. Antonio. ANSP 162178 View Materials , 1 View Materials (1, 134.8 mm SL), río Orinoco , backwater behind sandy beach 1/2 hr upstream from Isla Tremblador , 10 Mar 1987, W. G. Saul, H. Lopez, J. Fernandez, O. Castillo, M. E. Antonio, & J. Moreno. ANSP 180229 View Materials , 4 View Materials (1, 93.4 mm SL), AUM 39228 View Materials , 4 View Materials (1, 106.9 mm SL), MCNG 54033 View Materials , 3 View Materials (1,82.3 mmSL), ríoOrinoco, CucueAmerindian Village 60 km E of San Fernando de Atabapo, 03.97380°, - 067.15821°, 3 Apr 2004, M. H. Sabaj, N. K. Lujan, D. C. Werneke, & L. S. deSouza. AUM 39231 View Materials , 2 View Materials , 1 View Materials c&s, río Ventuari beach across the river from Picua Village 34 km ENE of Macuruco 104 km E of San Fernando de Atabapo, 04.11534°, -066.76457°, 5Apr 2004, M.H.Sabaj, N.K. Lujan, D. C.Werneke, L. S. de Souza, & O. León. ANSP 180230 View Materials , 2 View Materials (2, 77.2–103.6 mm SL), AUM 39244 View Materials , 2 View Materials (2, 89.4–105.6 mm SL), MCNG 54034 View Materials , 2 View Materials (2, 58.2–103.7 mm SL), río Ventuari 23 km NE of Macuruco 94 km E of San Fernando deAtabapo, 04.08042°, -066.86513°, 5 Apr 2004, N. K. Lujan, D. C. Werneke, M. H. Sabaj, L. S. deSouza, & O. León. ANSP 180231 View Materials , 2 View Materials (2,97.4–125.2 mmSL), AUM 39283 View Materials , 3 View Materials (3, 51.5–121.0 mm SL), MCNG 54035 View Materials , 2 View Materials (2, 57.3–109.0 mm SL), río Parucito at raudales Salomon 2.7 km NE of San Juan de Manapiare, 05.34637°, -066.03347°, 16 Apr 2004, D. C. Werneke, N. K. Lujan, & O. León. ANSP 180236 View Materials , 3 View Materials (1, 121.0 mm SL), AUM 42117 View Materials , 3 View Materials (1,134.4 mm SL), MCNG 54036 View Materials , 1 View Materials , same data as holotype. ANSP 180233 View Materials , 3 View Materials (1, 60.3 mm SL), AUM 42124 View Materials , 3 View Materials (1,115.3 mm SL), MCNG 54037 View Materials , 2 View Materials (1,39.0 mm SL), río Orinoco 33.9 km W of La Esmeralda at Punto Piaroa , 03.14744°, - 065.85381°, 28 Mar 2005, N. K. Lujan, M. Arce, T. E. Wesley, M. B. Grant, E. L. Richmond, J. Valadez, & D. Brooks. AUM 42140 View Materials , 2 View Materials (2, 132.8– 134.2 mm SL), Pasaganado 38 km N of San Fernando de Atabapo, 04.38442°, -067.77444°, 1 Mar 2005, N. K. Lujan, D. C. Werneke, M. H. Sabaj, M.Arce, & T. E. Wesley. ANSP 180232 View Materials , 2 View Materials (1, 99.9 mm SL), AUM 42146 View Materials , 2 View Materials (1, 108.9 mm SL), ríoVentuari163 kmSEofSamariapo, 04.05736°,-066.93257°, 1 Apr 2005, N. K. Lujan, M. Arce, T. E. Wesley, E. L. Richmond, & M. B. Grant. AUM 42174 View Materials , 2 View Materials (2, 79.7–100.7 mm SL), río Orinoco 60 km E of San Fernando de Atabapo, 03.97401°, - 067.16276, 3 Mar 2005, N. K. Lujan, D. C. Werneke, M. H. Sabaj,& M.Arce. AUM 42212 View Materials , 2 View Materials (2, 36.9–108.8 mm SL), MCNG 54038 View Materials , 2 View Materials (1, 93.8 mm SL), río Ventuari near ornamental fish market in river, 04.07565°, -066.89285°, 3 Apr 2005, N. K. Lujan, M. Arce, E. L. Richmond, M. B. Grant, & T. E. Wesley. AUM 42929 View Materials , 1 View Materials (1, 108.3 mm SL), río Orinoco at Macuruco landing, 03.95820°, -067.03210°, 30 Mar 2005, N. K. Lujan, M.Arce, E. L. Richmond, M. B. Grant, J. Valadez, D. Brooks, & T. E.Wesley. AUM 42931 View Materials , 1 View Materials (1, 65.0 mm SL), río Orinoco beach and bedrock outcropping 50 km E of San Fernando de Atabapo, 03.97029°, -067.25506, 2 Mar 2005, N. K. Lujan, D. C. Werneke, M. H. Sabaj, M. Arce, R. Betancur, & T. E. Wesley. AUM 42932 View Materials , 1 View Materials (1, 140.2 mm SL), río Orinoco island W of Puerto Venado 4.5 km S of Samariapo 56.5 km SE of Puerto Ayacucho, 05.20708°, - 067.80900°, 28 Feb 2005, N. K. Lujan, D. C. Werneke, M. H. Sabaj, M. Arce, R. Betancur , and T. E. Wesley. MCNG 30361 View Materials , 1 View Materials (1, 112.0 mm SL), río Orinoco in front of Macuruco , 5 Aug 1994, A. Barbarino, I. Lopez, & R. Berrios   .

Non-types. VENEZUELA, Amazonas, río Casiquiare drainage   : AUM 42201 View Materials , 1 View Materials (1, 73.3 mm SL), río Casiquiare 153 km NE of San Carlos de río Negro , 02.79877°, -066.00652°, 24 Mar 2005   . ANSP 180234 View Materials , 1 View Materials (1, 38.3 mm SL)   , AUM 42930 View Materials , 1 View Materials (1, 89.4 mm SL)   , MCNG 54039 View Materials , 1 View Materials (1, 51.7 mm SL), río Casiquiare left bank upstream from mouth of río Siapa , 02.15570°, -066.46377°, 19-22 Mar 2005   . ANSP 180235 View Materials , 2 View Materials ,   AUM 42933 View Materials , 2 View Materials (1, 146.9 mm SL), río Casiquiare bedrock riffle and outcrop 74.6 km NE of San Carlos de río Negro , 02.36280°, -066,56483°, 9 Mar 2005   . MCNG 12362 View Materials , 2 View Materials (2, 62.1–65.9 mm SL), raudal Cabarua approximately 5 km N of confluence with río Siapa , 02.11667°, -066.46667°, 18 Apr 1985   .

Diagnosis. Hemiancistrus subviridis   can be separated from all other hypostomines except Baryancistrus demantoides   by having a light gold-olive base color in life with goldenyellow spots, and from B. demantoides   by lacking a membranous connection between the dorsal and adipose fins and by having 9-29 left dentary teeth (vs. 34-51). Hemiancistrus subviridis   when preserved is very similar to the sympatric H. guahiborum   from which it differs by lacking an orange band at the edge of its dorsal and caudal fins and by having 9-29 left dentary teeth (vs. 28–72). The only other species of Hemiancistrus   with light spots are H. chlorostictos   , H. fuliginosus   , H. macrops   , H. meizospilos   , and H. votouro   . In addition to the light gold-olive base color (vs. dark gray base color), H. subviridis   can be separated from H. chlorostictos   , H. fuliginosus   , H. meizospilos   , and H. votouro   by having a forked caudal fin (vs. an emarginate caudal fin) and by having 9-29 left dentary teeth (vs. 41-86); and from H. macrops   by having the light spots restricted to the anterior half of the body (vs. all over).

In addition, Hemiancistrus subviridis   can be separated from all ancistrins except Baryancistrus   , other Hemiancistrus   , Hypancistrus   , Panaque   , Parancistrus   , Peckoltia   , and some Pseudancistrus   by lacking odontodes on the opercle; from Ancistrus   , Dekeyseria   , Lasiancistrus   , Neblinichthys   , and Pseudolithoxus   by having five rows of plates on the caudal peduncle (vs. three); from Hopliancistrus   by having more than 10 relatively straight hypertrophied odontodes on the evertible cheek plates (vs. usually less than five strongly recurved hypertrophied odontodes); from Exastilithoxus   and Lithoxus   by having oval lips (vs. round); from Acanthicus   , Chaetostoma   , Cordylancistrus   , Dolichancistrus   , and Leptoancistrus   , Leporacanthicus   , Megalancistrus   , and Pseudacanthicus   by having seven dorsal-fin rays (vs. eight or more); from Acanthicus   , Dekeyseria   , Leporacanthicus   , Megalancistrus   , and Pseudacanthicus   by lacking keels on the lateral plates; from most Pseudancistrus   by lacking hypertrophied odontodes around the snout; from Pseudancistrus sidereus   and P. megacephalus   by having spots only anteriorly on the body (vs. all over); from Baryancistrus   by not having the posterior portion of the dorsal-fin membrane expanded; from Parancistrus   , Spectracanthicus   , and most Baryancistrus   by not having the dorsal fin connected to the adipose fin; from Panaque   by having viliform teeth (vs. spoon-shaped teeth or elongated teeth); from Peckoltia   by having light spots (vs. dark spots or saddles); and from Hypancistrus   by having the teeth of the dentary and premaxillary of equal size (vs. dentary teeth longer than premaxillary teeth).

Description. A member of Subfamily Hypostominae   , Tribe Ancistrini   as diagnosed by Armbruster (2004). Morphometrics in Table 1. Medium-sized loricariids, largest specimen 149.5 mm SL. Body stout. Head sloped at approximate 30° angle to point above anterior portion of eye. Nape ascending slightly to insertion of dorsal fin. Dorsal slope decreasing to insertion of dorsal procurrent caudal rays then ascending to caudal fin. Body depth greatest below insertion of dorsal fin. Ventral profile flat to caudal fin. Caudal peduncle triangular in cross section with dorsal surface flattened. Body widest at insertion of pectoral fins, narrowest at insertion of caudal fin. Snout rounded.

Eyes moderately sized. Iris with dorsal flap. Interorbital space flat. Slight ridge formed between anterodorsal margin of orbit and nares. Supraoccipital pointed posteriorly, not elevated above nuchal plate. Infraorbitals, frontal, nasal, pterotic, and supraoccipital supporting odontodes. Preopercle and opercle not supporting odontodes.

Lips covered with short, wide papillae. Lower lip wide, upper lip narrow. Maxillary barbel only barbel present, reaching more than one third of distance to gill opening.

Median plates 23–25 (mode = 24). Plates unkeeled. Five caudal peduncle plate rows. Plates on all surfaces of body except for small naked upside down V-shaped wedge on the anteroventral margin of snout, throat, and abdomen behind pectoral. Some small embedded plates ventral to pectoral girdle and along ventromedial insertion of pectoral fin. Evertible cheek plates supporting hypertrophied odontodes that can be everted perpendicular to head. Cheek odontodes 17–74 (mode = 60). Longest evertible cheek odontode reaching cleithrum. Hypertrophied cheek odontodes relatively weak. Slightly longer odontodes present along dorsal-, adipose-, pelvic-, caudal-, and pectoral-fin spines; larger individuals with hypertrophied odontodes at tip of pectoral spine.

Dorsal fin II,7; dorsal spinelet V-shaped, dorsal-fin locking mechanism present, last ray of dorsal fin reaching insertion of adipose spine when adpressed. Adipose fin with single preadipose plate and moderately long spine. Caudal fin i,14,i; caudal fin forked, ventral lobe longer than dorsal lobe, dorsal procurrent caudal rays four, ventral procurrent caudal rays four. Pectoral fin I,6; pectoral-fin spine reaching beyond insertion of pelvic-fin spine when adpressed ventral to pelvic fin. Pelvic fin i,5; pelvic-fin spine extending beyond base of anal fin when adpressed. Anal fin i,4; anal-fin spine slightly shorter than first ray.

Teeth bicuspid with lateral lobe three-quarters length of medial lobe and distal tip of lateral cusp one-half width of tip of medial cusp. 9-29 left dentary teeth (mode = 17). 10–28 left premaxillary teeth (mode = 19).

Color in life. Adults with light golden-olive ground color on body and fins. Head, anterior sides and skin covering dorsalfin base with distinct round golden-yellow spots. Spots usually confined to portion of sides anterior to last dorsal-fin ray, but sometimes continuing on dorsolateral plates to below adipose fin or slightly beyond. Spots largest and more remotely spaced on anterior body below dorsal fin, becoming gradually smaller and more closely spaced towards and onto snout. Dorsal fin with distinct golden-yellow spots largely confined to basal two-thirds of spine and rays (lacking from membranes and distal portions of spine and rays). Pectoral fin with smaller golden-yellow spots largely confined to basal one-half to basal three-quarters of rays.

Color in alcohol. Adults with head, sides and fins nearly uniform light to medium gray-brown (becoming lighter posteriorly); plated undersurfaces tan, naked abdominal region white to cream-colored (without markings). Light spots on head and anterior sides clearly evident; light spots on head smaller, more numerous, and more tightly spaced; lateral plates anterior to dorsal fin usually with two to five light spots per plate; light spots also evident on skin along dorsal-fin insertion. Light spots on dorsal fin largely restricted to basal two-thirds of spine and rays, lacking on membranes. Light spots usually lacking on paired fins but sometimes evident on anterior membranes of pectoral fin. Juvenile coloration more or less as described for adults except light spots in fins lacking.

Range. Hemiancistrus subviridis   is known from the río Orinoco upstream of Atures rapids to río Iguapo, the río

Ventuari, and the río Casiquiare upstream of the río Siapa ( Fig. 3 View Fig ).

Etymology. From the Latin subviridis   meaning greenish in reference to the olive base color in life.

Gut morphology and ecology. Gastrointestinal tract brown with yellow-green fat deposits, loosely attached to intestinal wall. Esophagus turns 90° toward right upon entering peritoneal cavity, extends straight to right for short distance, turns 90° toward posterior before transitioning into proximal (cardiac) stomach. Cardiac stomach extends posteriorly for two thirds of length then transitions into distal (pyloric) stomach by making a 180° turn such that pyloric portion exits anteriorly and lies to right of cardiac portion. Total length of stomach approximately 15 mm. Proximal intestines exit the anterior-facing pyloric stomach, turn 180° to cross dorsally over esophagus, then continuing posteriorly towards anus. Near the anus, the proximal and distal ends of intestines begin a parallel, clockwise spiral toward the left with coils accruing ventral toward stomach and esophagus. Proximal intestines spiral clockwise for half of entire intestinal length, turn 180° at their middle, then distal portion spirals back to anus. Length of intestines and stomach from 15–17 times SL. External diameter of intestines ranges from 1–2 mm.

Hemiancistrus subviridis   were most frequently encountered in cracks and interstitial spaces of granitic rocks in flow. Gut contents of all individuals consisted largely of small grained (<0.001 mm diameter) mineral/organic matrix resembling clay, with some larger (~1.0 mm diameter) grains resembling silica sand. Organic material embedded in matrix of one individual ( AUM 39283 View Materials ) included pieces of a moss-like nonvascular plant (Bryophyta), intact mayfly larvae (Ephemeroptera), midge larvae ( Chironomidae   ), unidentified fly larvae ( Diptera   ), a clump of filamentous algae, a piece of lignified vascular plant, and an ingested tooth of presumed endogenous origin. Organic components of diet inAUM 42140 consisted of unidentifiable pieces of insect exoskeleton, pieces of unidentifiable plant matter, and ingested teeth of presumed endogenous origin (n=2). The only identifiable organic components in anterior gut of AUM 42124 View Materials were ingested teeth of presumed endogenous origin (n=13).

MCNG

Museo de Ciencias Naturales de la UNELLEZ en Guanare

T

Tavera, Department of Geology and Geophysics

AUM

Auburn University Museum of Natural History

R

Departamento de Geologia, Universidad de Chile