Cathorops festae (Boulenger 1898)

Marceniuk, Alexandre P., Marchena, José & Betancur-R, Ricardo, 2016, Cathorops festae (Boulenger 1898) (Siluriformes; Ariidae), a valid species from Ecuador and Peru, Zootaxa 4170 (1), pp. 137-148 : 139-146

Cathorops festae (Boulenger 1898)

Figure 1 and 2 , Table 2 and 3

Arius festae Boulenger, 1898:5 (original description; Naranjal, western Ecuador).— Kailola & Bussing, 1995:866 (as status uncertain).—Marceniuk & Ferraris in Reis et al. 2003:453 (list, as species inquirenda).—Betancur-R. & Acero P., 2004:13 (as species inquirenda).— Ferraris 2007:56 (as species inquirenda).— Marceniuk & Menezes 2007:46 (as species inquirenda).— Marceniuk et al. 2009:274 (as species inquirenda).

Cathorops fuerthii (non Steindachner).— Sanchez, 2008:10, 20, 28 (list; in part).— Barriga, 2012: 113 (list; in part).— Moncayo & Noboa, 2014:2 (list; in part).— Jiménez-Prado et al., 2015: 399 (identification key; in part).

Diagnosis. Cathorops festae is distinguished from the eastern Pacific subcongeners by having a supraoccipital process broader on posterior portion (3.4−4.0% SL vs. 2.2−3.3% SL in all other representatives, excluded C. fuerthii ), longer nuchal plate (7.2−7.9% SL vs. 4.7−7.1% SL in all other representatives, excluded C. liropus , C. multiradiatus , C. taylori and C. tuyra ), and the edges of the distal third of the occipital process which present a marked anterior-posterior convergence (vs. parallel or subtly convergent in all other forms, except C. fuerthii and C. raredonae , Fig. 2 f,g). The species can be further differentiated as follows: from C. fuerthii , which ranges from Costa Rica to Panama, by its shorter distance between anterior nostrils (3.3−4.2% SL vs.4.4−6.0% SL), shorter distance between posterior nostrils (4.1−5.8% SL vs. 5.7−7.3% SL, rarely 5.8%), larger orbital diameter (4.1−5.4% SL vs. 3.2−4.1% SL, rarely 4.2%), longer supraoccipital process (12.0−14.1% SL vs. 10.4−11.9% SL), and longer caudal-fin upper lobe (31.3−32.8% SL vs. 28.3−30.7% SL); from C. hypophthalmus , which is found in Panama, by having 17-18 gill rakers on first brachial arch (vs. 37−40), 16−19 rakers on second brachial arch (vs. 37−40), narrower mouth (9.5−11.1% SL vs. 13.1−13.2% SL), shorter distance between anterior nostrils (3.3−4.2% SL vs. 6.9−7.1% SL), shorter distance between posterior nostrils (4.1−5.8% SL vs. 8.2−8.5% SL), deeper caudal-peduncle (7.8−9.0% SL vs. 7.3−7.5% SL), and caudal-fin lobes wide, rounded posteriorly (vs. narrow and pointed posteriorly); from C. liropus , which is found in Mexico, by caudal-fin lobes wide, rounded posteriorly (vs. narrow and pointed posteriorly); from C. manglarensis , which ranges from Colombia to Peru ( Fig. 3 ), by having 17−18 gill rakers on first brachial arch (vs. 13−16, Table 2), wider nuchal-plate (7.2−8.1 vs. 6.4−7.1, Fig. 4 a), and shorter anal-fin base (15.3−19.3% SL vs. 21.0−24.4% SL, Fig. 4 b); from C. multiradiatus , which ranges from Panama to Peru ( Fig. 3 ), by its longer distance from snout to dorsal fin (36.1−40.6% SL vs. 31.2−34.8% SL, Fig. 4 c), longer supraoccipital process (12.0−14.1% SL vs. 9.8−11.5% SL, Fig. 4 d), and shorter anal-fin base (15.3−19.3% SL vs. 20.0−23.2% SL, Fig. 4 b); from C. raredonae , which ranges from Mexico to El Salvador, by its longer supraoccipital process (12.0−14.1% SL vs. 8.7−10.5% SL), and wider nuchal-plate (7.2−8.1% SL vs. 5.9−7.1% SL); from C. steindachneri , which ranges from El Salvador to Panama, by its longer caudal-fin upper lobe (31.3−32.8% SL vs. 25.1% SL), longer caudal-fin lower lobe (29.7−32.8% SL vs. 23.8% SL), and caudal-fin lobes wide, rounded posteriorly (vs. narrow and pointed posteriorly); from C. taylori , which ranges from Guatemala to El Salvador, by its longer supraoccipital process (12.0−14.1% SL vs. 9.4−10.6% SL), and caudal-fin lobes wide, rounded posteriorly (vs. narrow and pointed posteriorly); from C. tuyra , which is found in Panama, by having 23−25 anal-fin rays (vs. 19−20); 17−18 gill rakers on first arch (vs. 19−22); and deeper caudal-peduncle (7.8−9.0% SL vs. 5.8−7.8% SL). Additionally, Cathorops festae is differentiated from the subgenus Precathorops [currently monotypic with C. (P.) dasycephalus ] found in the eastern Pacific by having 17−18 gill rakers on first brachial arch (vs. less than 10), vomerine tooth plates absent (vs. present in Precathorops ), and accessory tooth plates bearing molariform teeth (vs. conical in Precathorops ).

Gill rakers on the first gill arch 13 14 15 16 17 18 19 C. festae 1 3 C. manglarensis 1 2 4 2

C. multiradiatus 1 1 2 3 Cathorops festae is distinguished from the Western Atlantic subcongeners by having a supraoccipital process broader on posterior portion (3.4−4.0% SL vs. 2.0−3.2% SL in all other representatives, excluded C. arenatus and C. nuchalis ), and 17−18 gill rakers on first arch (vs. 14−16 or 19−24 in all other representatives, excluded C. arenatus , C. melanopus , C. spixii , and C. wayuu ). The species can be further differentiated from the Western Atlantic subcongeners as follows: from C. aguadulce , which is found in Mexico, by having 23−25 anal-fin rays (vs. 21); from C. arenatus , from mouth of the Orinoco River to Brazilian north coast, by having osseous medial groove long and progressively larger to posterior-anterior direction (vs. short and narrow at middle portion), shorter distance between anterior nostrils (3.3−4.2% SL vs. 4.1−5.8% SL, rarely 4.2%); from C. belizensis , from Belize, by having 23−25 anal-fin rays (vs.18−20), shorter distance between anterior nostrils (3.3−4.2% SL vs. 5.1−6.1% SL); from C. kailolae , which ranges from Mexico to Guatemala, by its wider cephalic shield ate supracleithrum area (17.7−19.8% SL vs. 15.3−17.3% SL), and longer nuchal-plate (7.2−7.9% SL vs. 5.3−6.9% SL); from C. mapale , which is found in Colombia, by its longer nuchal-plate (7.2−7.9% SL vs.6.8−7.1% SL, rarely 7.2%); from C. melanopus , which is found in Guatemala, by having 23−25 anal-fin rays (vs. 19−20); from C. nuchalis , which ranges from Venezuela to Guyana, by its shorter distance between anterior nostrils (3.3−4.2% SL vs. 4.3−5.5% SL, rarely 4.2% SL); from C. wayuu , which ranges from Colombia to Venezuela, by its shorter distance between anterior nostrils (3.3−4.2% SL vs. 4.1−5.2% SL, rarely 4.2%), and longer supraoccipital process (12.0−14.1% SL vs. 9.1−11.5% SL).

Description. Morphometric data in Table 3 . Head depressed, profile elevated posteriorly, straight at frontal and supraoccipital area. Snout short and transversely rounded. Anterior nostril round, with fleshy edge, posterior nostril covered by flap of skin; nostrils relatively close to one another and moderately close to orbit, not connected by fleshy furrow. Eye lateral and large; eyes distant to one another. Three pairs of moderately long teretiform barbels; maxillary barbel usually reaching or past base of pectoral-fin spine, lateral mental barbel reaching gill membrane edge, and mesial mental barbel not reaching gill membrane edge. Osseous bridge formed by lateral ethmoid and frontal long and slender, evident under skin. Cephalic shield exposed, rough and granulated; moderately long and large on lateral ethmoid, frontal, and supracleithrum areas. Anterior portion of dorsomedial groove of neurocranium fleshy, conspicuous and not continuous to level of posterior nares; posterior portion of osseous groove, deep and conspicuous, with straight margins, narrowing posteriorly. Supraoccipital process funnel-shaped, very long and wide on posterior portion, and profile straight. Nuchal plate crescent-shaped, very long and wide.

Mouth subterminal to terminal, relatively large; lower jaw arched. Lips moderately thick, lower lip as thick as upper lip. Vomerine tooth plates absent. One pair of oval shaped accessory tooth plates, variable in size, closer to one another anteriorly, with molariform teeth. Premaxilla relatively long and narrow, with sharp teeth. Dentary separated at midline, with posterior expansion and sharp teeth on anterior portion, molariform teeth on posterior portion and some conical teeth interspersed. Gill membranes fused, attached to isthmus. Seventeen to 18 acicular gill rakers on first arch, 16–19 spike-shaped gill rakers on second arch. Mesial surfaces of all gill arches with developed gill rakers, lateral and mesial surfaces of first and second gill arches lacking fleshy papillae intercalated with gill rakers.

Body width greater than depth in pectoral girdle area, progressively more compressed from pectoral fin to caudal peduncle. Lateral line sloping ventrally on anterior one-third, extending posteriorly to caudal peduncle, bending abruptly onto dorsal lobe of caudal fin. Dorsal-fin spine moderately long and thick; anterior margin with granules; posterior margin with serrations along almost its entire length. Seven soft dorsal-fin rays. Pectoral-fin spine moderately long, shorter than dorsal-fin spine; anterior margin with granules on basal two-thirds and distal one-third with short serrations; posterior margin straight on basal one-fourth, distal three-fourths with serrations. Ten soft pectoral-fin rays. Posterior cleithral process exposed, smooth and triangular shaped, short and pointed posteriorly. Pelvic fin deep and long at base, with six rays. Adipose-fin base short, less than one-half the length of anal-fin base, anterior origin at level of anterior half of anal fin. Anal fin deep and moderately long at base, with 23–25 rays and distal margin slightly concave. Caudal peduncle relatively high. Caudal fin forked, dorsal and ventral lobes moderately long, wide and rounded posteriorly; dorsal lobe longer than ventral lobe.

Coloration. Grayish to dark brown on dorsum, silvery on flanks and white on abdomen. In alcohol, dark brown on dorsum, flanks brownish to silvery and white on venter; fins brownish. Maxillary barbel dark, mental barbel lighter ( Fig. 1 a,b, 2a,b).

Sexual dimorphism. Sexual dimorphism was not observed in the specimens examined (159–179 mm SL).

Distribution and habitat. Cathorops festae has been described from freshwater environments in Ecuador. The new specimens collected (LBP 19381) indicate that the species also occurs in the estuaries of northern Peru ( Fig. 3 ).

Size. The largest examined specimen had a standard length of 179 mm (LBP 19381).

Molecular evidence and phylogenetic relationships. Based on the relationships among the 16 Cathorops species inferred from the mitochondrial sequences using the maximum likelihood approach in RAxML and Bayesian Inference, C. festae from Ecuador and Peru are conspecific and together with C. multiradiatus , found from Pacific Panama to Ecuador, represent the most basal group in the subgenus Cathorops ( Fig 5 ).

Remarks. Arius festae Boulenger, 1898 was originally described from Naranjal, western Ecuador, remaining for a long time known only from the holotype (MZUT 1479), with its taxonomic status being considered uncertain ( Kailola & Bussing, 1995), or as a species inquirenda ( Marceniuk & Ferraris, 2003; Ferraris 2007; Marceniuk & Menezes 2007, Marceniuk et al. 2009). Its status has been challenged on the basis of third-party examination and photographs of the holotype, as well as molecular data obtained from specimens collected near the type locality ( Marceniuk et al., 2009, Betancur-R., et al., 2012). In the present study, Cathorops festae is recognized as a valid species, distinct from the other members of the genus found in Ecuador and Peru, based on the analysis of the holotype and other, non-type specimens, in which the profile of the distal third of the occipital process is characterized by the marked anterior-posterior convergence of the edges ( Fig. 2 a,b,f), the wider nuchal plate, the shorter base of the anal fin, the greater distance between the snout and the dorsal fin, and the greater length of the occipital process ( Fig. 4 ). Differences in morphometric ratios between the holotype from Ecuador (83 mm SL) and non-type specimens from Peru (159-179 mm SL) are probably the result of ontogenetic variation, which is common in other species of Cathorops .

Material examined. Type-specimen: holotype, MZUT 1479 , Naranjal , Ecuador . Non-type specimens: LBP 19381 (4, 159−179), Tumbes, Peru, in November 2014.

Figures

FIGURE 1. Body in lateral view. A. Cathorops festae, holotype MNHN 2002 - 0871, 83 mm SL; B. Cathorops festae, LBP 19381, 179 mm SL; C. Cathorops equatorialis, holotype USNM 53470, 158 mm SL; D. Cathorops multiradiatus, neotype USNM 79408, 192 mm SL; E. Cathorops manglarensis, holotype USNM 286392, 164 mm SL.

FIGURE 2. Head in dorsal view. A. Cathorops festae, holotype MNHN 2002 - 0871, 83 mm SL; B. Cathorops festae, LBP 19381, 159 mm SL; C. Cathorops equatorialis, holotype USNM 53470, 158 mm SL; D. Cathorops multiradiatus, neotype USNM 79408, 192 mm SL; E. Cathorops manglarensis, holotype USNM 286392, 164 mm SL; F. medial groove and occipital process of Cathorops festae; G. medial groove and occipital process of Cathorops manglarensis and Cathorops multiradiatus.

FIGURE 3. The Pacific coast of Central and South America, showing the geographic distribution of Cathorops festae (light blue), Cathorops manglarensis (red), and Cathorops multiradiatus (yellow).

FIGURE 4. Plots of standard length versus nuchal plate width (A), anal fin base length (B), distance from snout to dorsal fin (C), and supraocciptal process length (D), in Cathorops festae (open square = type specimen; solid squares = non type specimens), C. manglarensis (solid triangle = holotype; open triangles = paratypes; open diamond = specimen from Peru), C. multiradiatus (solid circle = neotype; open circle = non-type specimens), and the Tachysurus equatorialis holotype (asterisk).

FIGURE 5. A, Cathorops clade extracted from the Ariidae tree of Betancur-R. et al. (2012), including one individual of C. festae (shown in bold). The complete time tree was estimated using a Bayesian analysis of five mitochondrial and six nuclear gene fragments and 19 calibration points (both inside and outside Ariidae). B, RAxML tree estimated with expanded specimen sampling for Cathorops (including two individuals of C. festae, shown in bold), but based on the analysis of only two mitochondrial genes (Cyt b and ATPase 8 / 6). Nodal numbers indicate bootstrap support values. Two letter country codes follow ISO- 3166.

Tables

TABLE 3. Morphometrics for Cathorops festae. Standard length is expressed in millimeters, other measurements are percents of standard length. Range include non-type specimens only.

Cathorops festae	holotype	N	Mean	Range
Standard length (mm)	83	4		159−179
Head length	25.3	4	27.5	26.5−28.2
Snout length	8.4	4	7.7	7.0−8.6
Distance between anterior nostrils	3.3	4	4.0	3.9−4.2
Distance between posterior nostrils	5.2	4	5.1	4.1−5.8
Distance between anterior nostril and orbit		4	7.0	6.2−7.7
Distance between posterior nostril and orbit		4	5.1	4.4−5.8
Orbital diameter	5.4	4	4.3	4.1−4.4
Interorbital distance	12.3	4	14.4	13.4−15.0
Maxillary barbel length	30.4	4	28.1	26.5−31.0
Lateral mental barbel length	26.7	4	22.0	18.8−24.5
Mesial mental barbel length	19.4	2	13.7	12.4−14.9
Mouth width	9.5	4	10.4	9.7−11.1
Width of cephalic shield at lateral ethmoid area	13.8	4	12.6	12.0−13.3
Width of cephalic shield at frontals area	7.8	4	6.3	6.2−6.5
Width of cephalic shield at epioccipital area		4	12.7	12.4−13.2
Width of cephalic shield at supracleithrum area	17.7	4	19.5	19.1−19.8
Supraoccipital process length	12.0	4	13.2	12.7−14.1
Supraoccipital process width		4	3.7	3.4−4.0
Nuchal-plate length	7.2	4	7.5	7.3−7.9
Nuchal-plate width	7.2	4	7.8	7.6−8.1
Body depth	16.2	4	19.0	18.1−19.9
Body width	19.0	4	22.6	21.7−23.2
Distance from snout to pectoral fin	21.7	4	24.3	23.1−26.5
Distance from snout to dorsal fin	36.1	4	39.3	37.9−40.6
Distance from snout to pelvic fin	48.2	4	53.1	51.6−54.1
Distance from snout to adipose fin	70.0	4	79.5	77.8−80.8
Distance from snout to anal fin	66.3	4	71.9	71.3−72.4
Caudal-peduncle height	7.8	3	8.5	8.2−9.0
Pectoral-fin spine length	18.3
Dorsal-fin spine length	20.6
Pelvic-fin base length	4.2	4	4.3	3.7−4.9
Pelvic-fin height	13.1	4	15.5	13.9−16.4
Adipose-fin base length		4	7.1	6.4−7.6
Adipose-fin height		4	3.9	3.3−4.6
Anal-fin base length	19.3	4	15.9	15.3−16.5
Anal-fin height	17.2	4	12.9	12.1−13.7
Caudal-fin upper lobe length		4	31.9	31.3−32.8
Caudal-fin lower lobe length		4	30.6	29.7−32.8