Description of two new species of Bujurquina (Teleostei: Cichlidae) from the Bolivian Amazon

Abstract Two new species of Bujurquina are described from the Bolivian Amazon basin. The first new species inhabits the Beni River drainage and is distinguished from its congeners in the combination of the following characters: longer snout, deeper head, body and caudal peduncle, shorter pectoral fin, more scales in the E1 series, discontinuous longitudinal band, bars 5 and 6 not fused, preopercular spot and coloration pattern on flank scales absent. The second new species inhabits the Mamoré and Iténez river drainages, and differs from its congeners in the combination of the following characteristics: longer and deeper head, longer snout and pectoral fin, deeper caudal peduncle, fewer scales in the E1 series and lower lateral line, preopercular spot absent, bars 6 and 7 separated from longitudinal band and discontinuous longitudinal band. An identification key for species reported from Bolivia and complementary morphological data for B. oenolaemus and B. vittata are presented.


INTRODUCTION
Bujurquina Kullander, 1986 is distinguished morphologically from similar genera by the presence of a uniserial predorsal scale pattern, a dorsal notch in the ceratohyal for the hyoid artery, accessory lateral line scales between caudal-fin rays D1 and D2, an oblique lateral band running from the opercular cleft toward the end of the soft dorsal fin, and a headband across the nape that is usually attached to the lateral band (Kullander, 1986).It is phylogenetically considered a monophyletic group, which alongside Andinoacara Musilová, Říčan &Novák, 2009 andTahuantinsuyoa Kullander, 1986, comprises the BAT clade, within the Tribe Cichlasomatini of the subfamily Cichlinae (Ilves et al., 2018).
Recent field collections and examination of material deposited in Bolivian museums revealed undescribed species of Bujurquina inhabiting foothills and lowlands of the Beni and Mamoré river drainages, which are main tributaries of the upper Madeira watershed in the Amazon.In this article, two new species of Bujurquina are described, together with a review of Bolivian species of the genus and a resulting key of identification.
The morphological variables corresponded to those proposed by Kullander (1980aKullander ( ,b, 1986)), except for two additional characters: pre-anal length (from the tip of the snout to the origin of the anal fin; point-to-point measurement) and length of the first ventral spine, were added (Fig. 1).The meristic variables were the number of scales in the E1 line; number of predorsal and circumpeduncular scales; number of upper and lower lateral line scales; number of spines and soft dorsal rays; number of spiny and soft anal rays.Counts indicated by an asterisk belong to the holotype.Coloration variables (Fig. 2) were suborbital band (absence vs. presence), nape band (absence vs. presence), interorbital band (absence vs. presence), preopercular spot (absence vs. presence), caudal spot (absence vs. presence), opercular spot-longitudinal band (united vs. separated), buccal spots (presence vs. absence), bar 6-longitudinal band (united vs. separate), bar 7-longitudinal band (united vs. separate), bar 7 (single vs. bifurcated bar), bar 7-dorsal fin (united vs. separate), bars 5-6 (united vs. separate), longitudinal band (continuous vs. discontinuous) and longitudinal band-caudal peduncle (posterior branch of longitudinal band ends at dorsal fin vs. caudal peduncle).Available photographs from Kullander (1981Kullander ( , 1986Kullander ( , 1987) ) and Arbour et al. (2014) were examined to consider coloration variation.
Descriptions and publications used for comparison were Heckel (1840), Regan (1905), Eigenmann, Kennedy (1903), Eigenmann (1922), Kullander (1981Kullander ( , 1986Kullander ( , 1987)), Arbour et al. (2014), Hablützel, Huanto (2020).For the development of the diagnoses and the identification key for Bolivia, our results and the previously cited literature were combined.Diagnostic variables were corroborated using ImageJ software (Schneider et al., 2012).The procedure consisted in obtaining morphometric data of holotypes from photographs available in descriptions (Arbour et al., 2014;Kullander, 1981Kullander, , 1986Kullander, , 1987)).The specimens examined in this study were also subjected to the same procedure for comparisons with different holotypes under equal conditions.Description.Measurements summarized in Tab. 1.No apparent sexual dimorphism.Head slightly wider ventrally than dorsally.Body moderately elongated, lateral profile more convex dorsally than ventrally.Dorsal profile of head ascending, straight from tip of snout to posterior margin of orbit, convex to insertion of dorsal fin; dorsal-fin base ascending, convex to about 4 th dorsal-fin spine, descending convex to end of soft dorsal fin.Dorsal and ventral caudal peduncle profile straight to caudal-fin base.Ventral profile of head descending, slightly convex from lower lip to isthmus, slightly concave at isthmus, convex to insertion of pelvic fin, straight to insertion of anal fin, ascending anal fin slightly convex.Jaws isognathous, thick lips.Mouth small, maxilla does not reach vertical line from anterior margin of orbit.
Teeth in outer hemiseries conical, unicuspid, progressively smaller posteriorly.Three rows of smaller teeth behind.Dentary hemiseries with conical, recurved, and unicuspid teeth, three to four rows of smaller teeth behind.Nine external rakers in first-gill arch.Vertebrae 12+12, three of the 12 caudal vertebrae contained in the caudal peduncle.

Coloration in alcohol.
Background color brownish yellow, darker dorsally.Chest, suboperculum, and interoperculum with pale coloration.Dorsally darker operculum.No dark spot on inside of pectoral axilla.Broad, straight, diffuse, or marked brown suborbital stripe, with extension towards anterior arm of preoperculum.Distinctive dark nape band.No preopercular spot.Broad brownish-gray interorbital band, with extension between orbits and nostrils.Mouth spots in large specimens.Iridescent green spots in live specimens on preoperculum and operculum (Fig. 4).Lateral bars faint but distinct, darker dorsally, reaching ventrally to lower edge of caudal peduncle level.Bars 1 to 3 straight, bars 4 to 6 curved above lateral band, bar 6 continuous or discontinuous with lateral band.Wide bar 7, around origin of dorsal fin, continuous or discontinuous with lateral band.Dark lateral band extending below upper lateral line to end of dorsal fin along upper edge of caudal peduncle.Lateral band continuous anteriorly with dark spot on operculum connecting with nape band.Lateral band discontinuous posteriorly between lateral bars, especially between bars 4-5 and 5-6.Mediolateral spot on bar 5 blackish, often larger than other spots in lateral band.In addition, horizontal rows of iridescent green spots on flanks of live specimens (Fig. 4).Dorsal-fin lobes grayish with 9/21 ni.bio.br| scielo.br/niMatías Careaga, Guido Miranda and Fernando M. Carvajal-Vallejos whitish edges.Dorsal fin with grayish background, without spots in spiny portion and with hyaline spots in last five membranes of soft portion.Anal fin grayish with dark lower edge and hyaline spots in rows on last two membranes.Caudal fin grayish with dark margins and some dark spots at its base.Pelvic fin grayish with white anterior border.In live specimens, fin rays with yellowish color.Small, vertically elongated, dark caudal spot above lower lateral line, without clear border.No coloration pattern on flank scales.Geographical distribution.Bujurquina beniensis is known from localities in the Río Beni drainage, a main tributary of the Río Madeira, Amazon basin (Fig. 5).
Ecological notes.This species inhabits streams and whitewater riverbanks in the foothills of the Río Beni drainage (Fig. 6).
Description.Measurements summarized in Tab. 1.No apparent sexual dimorphism.Head slightly wider ventrally than dorsally.Body deeper than B. beniensis, lateral profile more convex dorsally than ventrally.Dorsal profile of head ascending, straight from tip of snout to posterior margin of orbit, straight with minor upward slope to insertion of dorsal fin; dorsal-fin base ascending, convex to about 5 th dorsal-fin spine, descending convex to end of soft dorsal fin.Dorsal and ventral caudal peduncle profile straight to caudal-fin base.Ventral profile of head descending, slightly convex from lower lip to insertion of pelvic fin, straight to insertion of anal fin, ascending anal fin slightly convex.Jaws isognathous, thin lips.Small mouth, maxilla does not reach vertical line from anterior margin of orbit.
Teeth in outer hemiseries conical, unicuspid, progressively smaller posteriorly.Three rows of smaller teeth behind.Dentary hemiseries with conical, recurved, unicuspid teeth, three to four rows of smaller teeth posteriorly.Eight external rakers in first-gill arch.Vertebrae 11+12, two of the 12 caudal vertebrae contained in the caudal peduncle.

Coloration in alcohol.
Background color brownish yellow, darker dorsally.Chest, suboperculum, and interoperculum with pale coloration.Operculum dorsally darker.Suborbital stripe straight and broad, diffuse or marked brown, with extension towards anterior arm of preoperculum.Faint nape band.No preopercular spot.Broad brownishgray interorbital band, between orbits and nostrils.Absence of stripes or buccal spots.Live specimens with iridescent green spots on preoperculum and operculum.Lateral bars faint but distinct, darker dorsally, with ventral extension to lower edge of caudal peduncle Matías Careaga, Guido Miranda and Fernando M. Carvajal-Vallejos especially between bars 4-5.Mediolateral spot on bar 5 blackish, often larger than other spots on lateral band.Live specimens with iridescent green spots in horizontal rows on flanks.Gray lobes in dorsal fin with whitish edges.In live specimens, orange coloration above whitish border on dorsal-fin end.Grayish dorsal fin with row of hyaline spots on its upper part.Spiny dorsal fin immaculate in most specimens, but some with dark spots at base of fin.Soft part of dorsal fin with hyaline spots on its last five membranes.Grayish anal fin with dark lower edge and hyaline spots in rows on last three membranes.Caudal fin grayish immaculate with some dark spots at its base.Pelvic fin grayish with whitish anterior border.Small, vertically elongated, dark caudal spot above lower lateral line, without clear No coloration pattern on flank scales (Fig. 8).

Geographical distribution.
Bujurquina mabelae is known from different localities in the Río Iténez and Río Mamoré drainages (Fig. 5).These drainages are important tributaries of the Río Madeira, which flows to the Amazon basin.
Ecological notes.This species inhabits streams and riverbanks of white and clear water in the headwaters (i.e., piedmont; Fig. 9) of the Río Mamoré and Río Iténez drainages.In addition, records of this species have been obtained in lagoons of fluvial and tectonic origin in the middle of the Río Mamoré drainage.
Etymology.The species is named in honor of Mabel Maldonado Maldonado for her valuable contributions to the studies of fish ecology and aquatic environments, and continued support to systematics studies of fishes in Bolivia.A noun in a genitive case.Two new species of Bujurquina from Bolivia coloration variables considered diagnostic within Bujurquina may be difficult to observe in preserved specimens (e.g., fin coloration patterns) or doubtful (e.g., union of bars 5 and 6, a diagnostic character for B. cordemadi, present in some specimens of B. mabelae).Therefore, we have considered all possible coloration variables, keeping only the persistent ones.Finally, having additional morphological data for each of these species would be important, particularly for B. mariae, B. vittata, and B. zamorensis, since their descriptions are short and lack photographs.
Conservation status.Bujurquina beniensis was collected from different tributaries of the Río Beni drainage, corresponding to an Extent of Occurrence (EOO) of approximately 8,900 km 2 .No specific threats were detected, this species can be classified as Least Concern (LC) according to the International Union for Conservation of Nature (IUCN) categories and criteria (IUCN Standards and Petitions Subcommittee, 2022).
level.Bars 1 to 3 straight, bars 4 to 6 curved above lateral band, bar 6 discontinuous with lateral band.Bar 7 broad, around origin of dorsal fin, discontinuous with lateral band.Dark lateral band extending below upper lateral line to end of dorsal fin along upper edge of caudal peduncle.Lateral band continues anteriorly with dorsal spot of operculum and nape band.Lateral band discontinuous posteriorly between lateral bars, 15/21 ni.bio.br| scielo.br/ni Conservation status.Bujurquina mabelae is distributed in different tributaries of the Río Iténez and Río Mamoré drainages, with an Extent of Occurrence (EOO) of approximately 54,500 km 2 .Since no specific threats are detected, this species can be classified as Least Concern (LC) according to the International Union for Conservation of Nature (IUCN) categories and criteria (IUCN Standards and Petitions Subcommittee, 2022).

TABLE 1 |
Morphometry of BolivianBujurquina species.Measurements are presented as percentages of SL, except SL (mm).N = number of specimens; SD = Standard deviation. B