Lamontichthys maracaibero Taphorn & Lilyestrom, 1984

Lamontichthys maracaibero Taphorn & Lilyestrom, 1984 View in CoL Fig. 12

Lamontichthys maracaibero Taphorn & Lilyestrom, 1984a: 94-95 View in CoL , 98, fig.1, table 1 [original description; type locality: “ Venezuela, Zulia, Distrito Miranda, río Motatán in el

Table 2. Morphometric and meristic data for Lamontichthys llanero View in CoL and L. maracaibero View in CoL . SD = standard deviation. L. llanero View in CoL L. maracaibero View in CoL

Variable

N Range Mean SD N Range Mean SD

Standard length (mm) 37 32.4-162.5 104.1 9 63.4-210.2 150.0

Percents of standard length

Head length 37 17.4-23.2 19.0 1.4 9 16.7-21.4 18.0 1.6 Predorsal length 37 26.5-31.9 28.1 1.2 9 25.5-29.6 27.5 1.3

Postanal length 37 47.0-57.1 54.9 2.0 9 53.5-57.1 55.2 1.2 Abdominal lenght 36 13.7-15.8 14.6 0.5 9 13.7-16.3 15.0 0.9

Thoracic length 37 13.6-16.5 14.8 0.8 9 13.2-15.6 14.0 0.8 Dorsal-fin length 26 25.3-40.5 34.0 3.0 9 25.7-31.4 29.7 1.9 Pectoral-fin length 37 20.2-25.4 22.2 1.3 9 20.0-21.7 21.0 0.6 Pelvic-fin length 37 17.7-22.8 20.2 1.1 9 18.2-19.9 19.1 0.5

Anal-fin length 35 17.9-25.2 21.8 1.6 9 19.6-22.0 21.1 0.8

Body depth at dorsal-fin origin 37 9.6-13.6 11.5 1.0 9 11.4-15.1 13.6 1.5

Caudal peduncle depth 37 1.3-1.8 1.5 0.1 8 1.5-1.7 1.6 0.1

Body width at dorsal-fin origin 37 11.4-15.5 14.3 0.8 9 14.4-16.9 15.8 0.9

Body width at anal-fin origin 37 8.5-12.9 11.5 0.9 9 11.5-14.5 13.2 1.1

Body width at caudal-fin origin 37 2.3-3.1 2.8 0.2 9 2.3-2.8 2.5 0.2

Percents of head length

Head width 37 82.6-96.9 92.4 3.1 9 90-112.7 103.4 7.2 Interorbital distance 37 29.4-35.0 31.9 1.4 9 29.7-33.4 31.2 1.3

Orbital diameter 37 15.0-19.4 17.5 1.1 9 12.8-16.4 14.9 1.2

Snout length 37 54.8-61.8 59.3 1.4 9 57.7-64.2 61.5 2.0

Dentary length 37 11.7-15.6 13.6 0.8 9 13.0-19.1 16.9 1.8

Lower lip width 37 9.0-16.6 12.5 1.7 9 11.1-14.0 12.4 1.0

Meristic data

Lateral plates of median series 36 32-33 32.7 0.5 9 32-34 33.0 0.5

Lateral plates of mid-ventral series 36 15-17 15.9 0.6 9 18-20 18.9 0.8 Ventrolateral thoracic plates 36 5-10 8.2 1.1 9 5-6 5.3 0.5 Premaxillary teeth 34 33-75 58.2 9.8 9 58-100 84.8 15.5

Dentary teeth 32 27-60 47.3 7.4 9 57-91 75.3 11.4 Dorsal-fin rays 37 II,7 II,7 0.0 9 II,7-8 II,7 0.3 Pectoral-fin rays 37 I,7 I,7 0.0 9 I,7 I,7 0.0 Pelvic-fin rays 37 i,5 i,5 0.0 9 i,5 i,5 0.0

Anal-fin rays 37 i,5 i,5 0.0 9 i,5 i,5 0.0 Caudal-fin rays 36 i,12,i i,12,i 0.0 9 i,12,i i,12,i 0.0

Puente Tres de Febrero”; paratypes from río Motatán and río Ariguisá]; Taphorn & Lilyestrom, 1984b: 17, 29 [key and common name; lago Maracaibo, Venezuela]; Galvis et al., 1997: 88 [description, habits, common names, illustrations, río Catatumbo system in Colombia and Venezuela]; Provenzano et al., 1998: 11-12, 21, 23 [type listed]; Eschmeyer, 1998: 1014 [listed]; Mojica, 1999: 562 [listed]; Isbrücker, 2001: 29 [listed]; Ferraris Jr., 2003: 336 [listed]; Ferraris Jr., 2007: 264 [listed].

Diagnosis. Lamontichthys maracaibero differs from all congeners in the presence of a single plate ( vs. two plates) between the pelvic-fin base and the anterior margin of the anus ( Figs. 1 and 5).

Specimens of L. maracaibero larger than 150 mm SL possess a deeper body at the predorsal region (14.0-15.1%, n = 6, vs. 11.5-13.5%, n = 26) relative to the other species of Lamontichthys (except for L. parakana for which specimens larger than 150 mm SL were not available for comparison), forming a hump between the head and the dorsal-fin origin. Lamontichthys maracaibero is further distinguished from L. filamentosus and L. llanero by the semi-oval shape of the lower lip ( vs. semicircular) ( Fig. 9); and from L. llanero by the reduced number of lateroventral thoracic plates in specimens smaller than 50 mm SL (5 to 6 plates, vs. 7 to 10), and from L. stibaros , L. avacanoeiro , and L. parakana by having the snout totally covered with plates at its anterior tip ( vs. presence of an area lacking plates) and by the teeth with short cusps ( vs. long) ( Fig. 3). The specimens of Lamontichthys maracaibero larger than 100 mm SL also differs from L. stibaros , L. avacanoeiro , and L. parakana in the relatively shorter head (16.7-17.8%, vs. 19.8-23.0% SL) and shorter dentary (14.8-19.1%, vs. 18.4-23.4% HL). Morphometric and meristic data are presented in Table 2.

Geographic distribution. Lago Maracaibo basin ( Fig. 2).

Material examined ( 9 specimens; 63.4-210.2 mm SL): Colombia: ICNMHN 2166, 5, 149.1-210.2, Catatumbo, Santander, río Catatumbo , córrego La Gabarra . Venezuela: Trujillo: lago Maracaibo drainage: MCNG 3592 View Materials , 1 View Materials , 154.9 View Materials , holotype; MCNG 3593 View Materials , 1 View Materials (of 4), 63.4, 1 cs*, 83.8, paratypes, Betijoque, río Motatãn, bridge “Tres de Febrero”. Zulia: INHS 35473 About INHS , 1 About INHS , 131.3 About INHS , río Santa Rosa .