taxonID	type	description	language	source
03ABA119FF95FFBA5808ED004415FA3E.taxon	materials_examined	Type Species: Hypostomus barbatus Valenciennes 1840 Synonyms: Lithoxancistrus Isbrücker, Nijssen, and Cala 1988 Guyanancistrus Isbrücker 2001 Includes: P. barbatus (Valenciennes 1840)	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF95FFBA5808ED004415FA3E.taxon	description	P. brevispinis (Heitmans, Nijssen, and Isbrücker 1983) P. coquenani (Steindachner 1915) P. depressus (Günther 1868) P. genisetiger Fowler 1941 P. guentheri (Regan 1904)	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF95FFBA5808ED004415FA3E.taxon	diagnosis	Diagnosis: Pseudancistrus is not diagnosed by any unique characteristics. Characteristics considered as synapomorphies for Pseudancistrus from Armbruster (2004) are: no suture between pterotic­supracleithrum and hyomandibula (34 ­ 0, reversal), no contact of the hyomandibula with the prootic (35 ­ 1), straight, spoon­shaped anterior process of metapterygoid (58 ­ 1), nasal bone not much wider than laterosensory canal running through it (105 ­ 0), sphenotic not contacting posteriormost infraorbital externally (117 ­ 1), and a short ventral ridge on the pelvic basipterygium (172 ­ 1, lost in some species). Pseudancistrus can be separated from the Corymbophanini and the Hypostomini by having hypertrophied odontodes on the cheek; from most of the Rhinelepini by having an adipose fin and a dorsal flap of the iris and from Pogonopoma wertheimeri by having few or no plates on the abdomen (vs. abdomen fully plated); and from the Pterygoplichthini by lacking an enlarged, respiratory stomach and by lacking or nearly lacking plates on the abdomen (vs. abdomen fully plated in adults), and from Pterygoplichthys by having seven dorsal­fin rays (vs. nine or more). Within the Ancistrini, Pseudancistrus can be separated from Ancistrus, Dekeyseria, Exastilithoxus, Hopliancistrus, Lasiancistrus, most Lithoxus, Neblinichthys, and Pseudolithoxus by having 4 – 5 plate rows on the caudal peduncle (vs. 3); from Baryancistrus, Spectracanthicus, and Parancistrus by not having a membranous connection of the posterior end of the dorsal fin with the adipose fin; from some Hemiancistrus, Hypancistrus, Panaque, and Peckoltia by having 10 + odontodes on the opercle (vs. usually 0, but up to 10, odontodes); from Acanthicus, Leporacanthicus, Megalancistrus, and Pseudacanthicus by lacking hypertrophied keel odontodes on the lateral plates; from Ancistrus and Chaetostoma by having plates on the edge of the snout; and from Chaetostoma, Cordylancistrus, Dolichancistrus, and Leptoancistrus by having the spinelet and the nuchal plate of the dorsal fin supporting odontodes (vs. skin covering the spinelet and nuchal plate in all but adult male Dolichancistrus). Pseudancistrus can be separated from the Neopleostominae, Hemipsilichthys, and most of the Hypoptopomatinae by having a V ­ shaped dorsal­fin spinelet (vs. dorsal­fin spinelet rectangular or absent); from all of the Hyopotopomatinae by lacking odontodes on the ventral surface of the pectoral girdle; from the Loricariinae by having four or five rows of plates on the caudal peduncle (vs. three) and by having an adipose fin; and from Delturus and Hemipsilichthys (a new subfamily; Armbruster 2004) by having a single (rarely two) median, preadipose plates (vs. three or more).	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF95FFBA5808ED004415FA3E.taxon	description	Description: Member of subfamily Hypostominae, tribe Ancistrini as diagnosed by Armbruster (2004). Small to large loricariids. Ventral surface from anus to head largely naked in adults. Lateral plates unkeeled except ventral plate bent to form keel­like ridge on caudal peduncle, inframedian plate row bent from pectoral­spine insertion to above pelvic fin forming ridge, and dorsal plate row bent, forming ridge from insertion of dorsal­fin spine to posterior end of adipose­fin spine (ridges on either side converging at posterior end of adipose­fin spine). Cheek plates with numerous hypertrophied odontodes, longest odontode reaching almost to posterior edge of cleithral process; cheek odontodes and supporting plates evertible at an angle greater than 75 ° from head primitively although advanced species may not have evertible cheek plates, 15 – 60 evertible cheek odontodes. Frontal, infraorbitals, nasal, opercle, preopercle (in some species), pterotic­supracleithrum, and suprapreopercle supporting odontodes. Caudal fin emarginate to forked, lower lobe longer than upper. Lower surface flat. Head moderate in length with horizontal distance between anterior of eye and tip of snout long. Head dorsoventrally flattened. Body depth increasing slowly, in broad arc from tip of snout to insertion of dorsal fin. Body depth decreases very little to dorsal procurrent caudal­fin spines; body depth increases slightly from posterior adipose­fin insertion to insertion of upper caudal­fin spine. Dorsal surface of head between eyes moderately concave. Supraoccipital crest not raised, posterior edge of supraoccipital rounded. Eye large (Table 1) with well­developed dorsal flap of iris. Gill opening restricted. Dorsal­fin spine short (table 1); dorsal fin reaching posterior edge of preadipose plate when depressed in all species except Pseudancistrus sidereus where the dorsal fin does not reach preadipose plate. Depressed pectoral­fin spine reaching beyond base of pelvic­fin rays; depressed pelvic­fin spine typically reaching anterior insertion of anal fin (sometimes slightly beyond). Dorsal fin II 7, caudal fin I 14 I, anal fin I 4 – 5, pectoral fin I 6, pelvic fin I 5. Lips papillose, forming oval disk about as wide as head. Maxillary barbel short, thin, and pointed. Buccal papilla short, narrow. Teeth long, thin with pointed cusps, lateral cusp about half length of medial cusp, 45 – 89 dentary teeth, 38 – 94 premaxillary teeth. Color: Generally dark gray, lighter on abdomen. Some species with light spots or blotches on the sides. Some species with the body mottled gray or brown. Fins generally colored as sides, but some species with bands in the caudal fin, or with orange to red edging on the dorsal and / or caudal fins. Sexual Dimorphism: Most species with hypertrophied odontodes along the snout in both males and females, but males generally with longer snout odontodes. Pseudancistrus sidereus may have hypertrophied odontodes on the lateral plates (see description below). Some specimens with hypertrophied odontodes on tip of pectoral spine, but it is unknown if these are dimorphic. Ecology: Found in swift flow among gravel, cobble, and boulders. Range: Found around the Guyana Shield in the Guyanas, Venezuela, and Brazil. Also found in northeastern Brazil in the Rio Jaguaribe and Rio Grande do Norte.	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF96FFB75808EBB2437AF9A6.taxon	materials_examined	Holotype: VENEZUELA, Amazonas, Ro Orinoco dr.: MCNG 26125, 175.6, Río Siapa from 10 to 15 km downstream, Río Casiquiare – Río Negro dr., 01.50000 °, ­ 065.71667 °, ABD and F. Morillo, 20 April 1991. Paratypes. VENEZUELA, Amazonas, Río Orinoco dr.: MCNG 48261, 1, 1 CS, 149.8, AUM 37562, 1, 148.7, same data as holotype. FMNH 105294, 4, 149.5 ­ 176.7, Río Orinoco ca. 5 h above Atabapo by falca; at rocks and beach, B. Chernoff, A. and D. Machado, and J. Wheeler, 23 January 1991.	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF96FFB75808EBB2437AF9A6.taxon	diagnosis	Diagnosis: Pseudancistrus sidereus is diagnosed by a unique modification of the ventral plates on the caudal peduncle. In loricariids, the plates of the ventral row on the caudal peduncle are typically bent at an approximately 90 ° angle to follow the contour of the body. The bend is often the site of a slight keel formed from one or more rows of slightly longer odontodes. In P. sidereus, the keel is accentuated by having the dorsal laminae of the plates strongly concave. Although some loricariids may have the dorsal laminae slightly concave, it is much more pronounced in P. s i d e re u s. Pseudancistrus sidereus can be separated from all other species of the Ancistrini by the presence of the keel mentioned above and by the presence of a single large white to yellow spot located at the center of the posterior lateral plates. The only species with a similar coloration are some Hypancistrus and some Panaque, both of which have far fewer than 25 teeth per jaw ramus (vs. much more than 25 teeth), some other species of Pseudancistrus which have hypertrophied odontodes along the snout in males and females (vs. no hypertrophied snout odontodes), and have the dorsal fin reaching at least the preadipose plate when depressed (vs. about two plates anterior to preadipose plate); and some Hemiancistrus and Peckoltia which generally have the spots much more diffuse (vs. borders of spots distinct) and have the dorsal fin reaching at least the preadipose plate when depressed (vs. about two plates anterior to preadipose plate).	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF96FFB75808EBB2437AF9A6.taxon	description	Description. Fairly large loricariids, largest specimen 176.7 mm SL. Body elongate, fairly narrow, and dorsoventrally flattened. Head and anterior part of trunk gently sloped from snout tip to dorsal­fin origin, dorsal profile of body straight to adipose fin with slight decrease in depth, dorsal profile of caudal peduncle very concave, shallowest at posterior insertion of adipose fin. Ventral surface flat. Head contours smooth. Slight, rounded ridge from anterolateral corner of nares, above orbit to posterior edge of pterotic­supracleithrum, dorsal margin of orbit higher than mesial portion of head. Mesethmoid slightly higher than lateral surface of head forming rounded ridge on snout, continued posterior to mesethmoid and terminating at level of posterior margin of orbits. Supraoccipital with slight posterior point medially. Following head bones supporting odontodes: frontal, infraorbitals, opercle, nasal, pterotic­supracleithrum, sphenotic, supraoccipital, and suprapreopercle. Lips wide, fairly thin. Upper lip with wide, thin papillae. Lower lip with small papillae anteriorly, a band of larger papillae, and then smaller papillae posteriorly, papillae fading towards posterior edge. Maxillary barbel only barbel present, not reaching base of evertible cheek plates. Mouth with small, narrow buccal papilla. Iris with small dorsal flap, not reaching ventral to center of pupil. 25 plates in median series. Ventral plates forming a right angle on caudal peduncle with dorsal margin of plates concave forming a strong keel along lower portion of caudal peduncle. Dorsal plate series bent between dorsal and adipose fins to form slight ridge, ridges on two sides converging just posterior to insertion of adipose­fin spine. Inframedian plate series bent in middle from cleithrum to insertion of pelvic­fin forming slight keel. Abdomen naked except for some small, embedded plates laterally between pectoral and pelvic fins. Five rows of plates on caudal peduncle. 18 – 39 (average = 28, N = 7) evertible cheek odontodes. Evertible cheek odontodes fairly short, longest reaches posterodorsal corner of opercular opening. Evertible cheek odontodes supported by plates than can be everted up to approximately 90 ° from the head. Hypertrophied cheek odontodes relatively weak. Single adult male with modestly hypertrophied odontodes on tip of pectoral­fin spine, females with odontodes on tip of pectoralfin spine slightly longer than those at base (Fig. 3). All fin spines and rays supporting odontodes. Dorsal fin II 7; dorsal­fin spinelet Vshaped, dorsal­fin lock functional; dorsal­fin spine elongated relative to other fin rays in some specimens making edge of fin emarginate; dorsal fin not reaching adipose fin when adpressed. Adipose fin with single median preadipose plate and fairly long curved spine. Caudal fin I 14 I; caudal fin forked, lower lobe longer than upper; usually six dorsal and five ventral procurrent caudal­fin spines. Pectoral fin I 6; pectoral­fin spine reaching posterior insertion of pelvic fin to slightly beyond base of pelvic fin when adpressed ventral to pelvic fin. Pelvic fin I 5; pelvic­fin spine reaching end of base of anal fin when adpressed. Anal fin I 4; unbranched anal­fin spine ray two thirds the length of the first branched ray. First anal­fin pterygiophore not exposed to form a platelike structure. Teeth very long and bicuspid with a longer, median lobe. 73 – 85 dentary teeth (median = 77, N = 7). 78 – 93 premaxillary teeth (median = 84, N = 7). Jaws very wide, dentaries forming a very oblique angle, premaxillaries forming a gentle arc. Color. Ground color dark brown dorsally and laterally, fading to tan on ventral half of inframedian plate series, tan ventrally. Head with small white spots (possibly yellow in life), spots getting larger posteriorly. Usually 2 – 3 spots per plate anteriorly and one posteriorly. Ventral spots lengthening dorsoventrally on inframedian and ventral plates series until fading into ventral coloration. Ventral surface of upper lip brown. Dorsal­fin membranes hyaline or with slight spotting; dorsal­fin spine and rays with oval spots. Adipose fin with weak spots or mottled. Caudal fin distinctly lighter ventrally; spots on ventral lobe fairly large and round and spots on dorsal lobe smaller and oval. Leading edge of pectoralfin spine light; pectoral­fin spine with or without spots; small round spots centered on pectoral­fin rays; color slightly fading posteriorly on pectoral fin. Pelvic fin with larger spots fading distally, spots on both rays and membrane. Anal fin tan or mottled. Sexual dimorphism. One potentially nuptial male examined with hypertrophied odontodes on the sides similar to Peckoltia and Panaque (Panaqolus), but shorter and sharper. Hypertrophied odontodes on pectoral­fin spine larger in the potentially nuptial male. Range: Known from the Río Casiquiare drainage and the upper Río Orinoco drainage of Amazonas, Venezuela (Fig. 4).	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
03ABA119FF96FFB75808EBB2437AF9A6.taxon	etymology	Etymology: From the Latin sidereus for starry. Named because the dark background makes the white to gold spots look like stars.	en	Armbruster, Jonathan W. (2004): Pseudancistrus sidereus, a new species from southern Venezuela (Siluriformes: Loricariidae) with a redescription of Pseudancistrus. Zootaxa 628: 1-15, DOI: 10.5281/zenodo.158521
