Moema apurinan, Costa, Wilson J. E. M., 2004

Costa, Wilson J. E. M., 2004, Moema apurinan sp. n. and Aphyolebias boticarioi sp. n. (Teleostei: Cyprinodontiformes: Rivulidae): two new annual killifishes from the Rio Purus basin, Brazilian Amazon, Zootaxa 707, pp. 1-12 : 3-7

Moema apurinan new species

( Figs. 1–2 )

Holotype. UFRJ 5980, male, 52.5 mm SL; Brazil: Estado do Acre: Porto Acre, temporary pool within forest, Rio Acre floodplains, Rio Purus drainage, Rio Amazonas basin (9o35’12.2”S 67o31’50.6”W; altitude 132 m); W. J. E. M. Costa, S. Lima and A. Pinto, 10 June 2003.

Paratypes. UFRJ 5981, 4 males, 50.2–55.4 mm SL, 5 females, 42.7–51.1 mm SL; UFRJ 5982, 4 males, 48.2–54.4 mm SL, 3 females, 46.8–47.9 mm SL (c&s); collected with holotype.

Diagnosis: The new species differs from all other species of the genus in having fewer caudal­fin rays (30–31, vs. 32–35). It is similar to M. staecki (Seegers) , and distinguished from all other congeners by possessing contact organs on scales of the flank of the male (vs. contact organs absent), caudal fin acuminate (vs. rounded to subtruncate), fewer pectoral­fin rays (14, vs. 15–17), fewer vertebrae (33–35, vs. 36–39), and narrower rostral cartilage (width about 75–80% of rostral cartilage length, vs. 90–100% in the remaining species of the genus, except in M. ortegai Costa , about 145%). The new species differs from M. staecki by having a longer pectoral fin (tip reaching between the base of 8th and 13th anal fin rays, vs. reaching urogenital papilla), and wider basihyal (width about 75% of basihyal length, vs. 55 %).

Description: Morphometric data given in Table 1 . Male larger than female, largest male 55.4 mm SL. Dorsal profile gently convex from snout to end of dorsal­fin base, approximately straight to slightly concave on caudal peduncle. Ventral profile slightly convex on head, almost straight from anterior portion of venter to end of anal­fin base, nearly straight on caudal peduncle. Body slender, subcylindrical anteriorly, deeper than wide, to compressed posteriorly. Greatest body depth at level of pelvic­fin base. Jaws long, snout pointed.

Tip of dorsal fin pointed, with short filamentous ray in male, rounded to slightly pointed in female. Anal fin approximately rectangular, longer than deep; tip pointed, long, reaching vertical through middle of caudal fin in male, rounded and short in female. Caudal fin long, acuminate, with short posterior filamentous rays in male, short and elliptical in female. Pectoral fin lanceolate, terminating in long tip, reaching between base of 8th and 13th anal fin rays in male, slightly pointed and short, reaching between pelvic­fin base and anus in female. Pelvic fin rounded, tip reaching between base of 1st and 3rd anal­fin rays in male, and between anus and urogenital papilla in female. Pelvic­fin bases in close proximity. Dorsal­fin origin on vertical through base of 9th or 10th anal­fin ray, and between neural spines of 20th and 22nd vertebrae. Anal­fin origin between pleural ribs of 16th and 17th vertebrae. Dorsal­fin rays 10–11; anal­fin rays 16–17; caudal­fin rays 30– 31; pectoral­fin rays 14; pelvic­fin rays 7.

Scales large, cycloid. Body and head entirely scaled, except anterior ventral surface of head. Body scales extending over caudal­fin base; no scales on dorsal and anal fins. Frontal squamation E­patterned; E­scales not overlapping medially; scales arranged in irregular circular pattern around A­scale without exposed margins. Longitudinal series of scales 34– 35; transverse series of scales 8; scale rows around caudal peduncle 16. Ctenii­like contact organ on each scale of median ventral portion of male flank. Supraorbital neuromasts 3 + 3.

Interhyal vestigial, not ossified. Rostral cartilage longer than wide, width 75­80% length. Basihyal subtriangular, width 75% length; basihyal cartilage 45% basihyal length. Six branchiostegal rays. Second pharyngobranchial with no, one or two small teeth. Gillrakers of first branchial arch 1 + 10. Vomerine teeth 4–11. Ventral process of posttemporal present. Total vertebrae 33–35.

Coloration: Male: Side of body greenish golden, with three purplish brown stripes alternating with narrow dark golden stripes; dark red crimson dots simultaneously arranged both in longitudinal rows, on two dorsalmost purplish brown stripes, and in oblique rows crossing flank. Dorsum light brown with brown dots, venter white. Side of head greenish golden with dark brown blotches. Jaws light brown. Infraorbital region and ventral surface of head white. Iris yellowish green, with dark brown bar crossing center of eye. Dorsal fin pale greenish yellow with small dark reddish brown spots. Anal fin light greenish yellow, basal region light blue, with small dark reddish brown spots. Caudal fin pale greenish yellow with small dark reddish brown spots on dorsal portion and short brown stripes or dots parallel to fin rays on median portion; broad light orange stripe with bright yellow dorsal contour, dorsally outlined by dark brown stripe, on ventral margin of fin. Pelvic fin light greenish yellow, with transverse rows of small brown spots. Pectoral fin yellowish hyaline.

Female: Side of body light metallic green, with six longitudinal rows of brown dots. Dorsum light brown with brown dots, venter white. Side of head pale metallic green with faint brown spots. Jaws gray. Infraorbital region and ventral surface of head white. Iris yellow, with pale brown bar crossing center of eye. Dorsal and anal fins pale greenish yellow with small dark brown spots. Caudal fin pale greenish yellow with small dark brown spots on dorsal portion, and faint small gray spots on middle. Paired fins hyaline.

Distribution: Known only from the type locality, Rio Acre floodplains, Rio Purus drainage, Rio Amazonas basin, northwestern Brazil ( Fig. 3 ).

Habitat notes: The type series was collected in a temporary pool within the forest. The pool was small, about 7 m of long and about 3 m wide, shallow, about 0.40­0.60 m deep. The water was dark brown. No aquatic vegetation.

Etymology: The specific name apurinan (Apurinã) is the Portuguese name of an indigenous tribe of people, also known as Ipurinã, Popingaré and Kangitê, with own language derived from the linguistic group Aruak, inhabiting lands drained by the Rio Purus basin in the region of the type locality of the new species.

Figures

FIGURE 1. Moema apurinan, UFRJ 5980, male, holotype, 52.5 mm SL (one day after collection); Brazil: Acre: Porto do Acre: Rio Purus basin.

FIGURE 2. Moema apurinan, UFRJ 5981, female, paratype, 44.4 mm SL (one day after collection); Brazil: Acre: Porto do Acre: Rio Purus basin.

FIGURE 3. Geographic distribution of species of the genus Moema.

Tables

TABLE 1. Morphometric data of Moema apurinan. H: holotype.

			males	females
	H			paratypes (UFRJ 5981)
Standard length (mm)	52.5	55.4	53.8	53.3 50.2 51.1 46.3 45.3 44.4	42.7
Percents of standard length
Body depth	21.0	21.5	21.7	21.7 21.4 22.9 22.1 23.1 21.4	22.1
Caudal peduncle depth	14.1	15.2	15.2	14.9 14.7 13.7 13.8 14.5 13.2	14.0
Predorsal length	73.5	69.9	71.9	71.6 73.8 73.6 73.5 75.4 75.8	74.9
Prepelvic length	48.6	49.2	50.7	50.9 50.1 52.1 50.8 53.1 52.7	52.3
Length of dorsal­fin base	11.7	11.1	10.6	9.9 10.6 9.1 9.2 9.2 8.4	9.7
Length of anal­fin base	21.2	22.2	22.6	21.7 21.9 18.6 19.7 18.5 18.7	19.0
Caudal­fin length	52.7	­	64.6	62.2 58.2 41.1 42.8 44.7 44.3	41.5
Pectoral­fin length	41.7	­	46.6	37.8 48.1 26.4 25.0 25.7 29.6	24.5
Pelvic­fin length	14.4	15.0	15.9	14.6 15.7 12.9 12.3 12.5 13.6	11.8
Head length	26.3	25.8	25.9	25.0 25.4 25.9 26.7 26.9 28.5	26.8
Percents of head length
Head depth	66.0	69.6	67.6	67.9 67.5 70.7 65.3 68.1 63.3	67.3
Head width	63.1	66.8	65.5	65.3 67.0 72.7 69.9 70.9 66.7	70.3
Snout length	15.0	14.5	16.0	15.8 15.1 14.5 14.0 14.2 13.5	12.3
Lower jaw length	25.9	23.6	25.1	25.1 25.0 23.9 23.0 24.0 23.4	23.8
Eye diameter	31.6	32.2	32.1	32.2 33.3 33.0 35.3 35.0 32.1	34.4