Arrowhead Piculet vs Spotted Piculet

In short

Juvenile Arrowhead Piculet shows a plain brown crown and browner, more barred upperparts, while juvenile Spotted Piculet is duller overall but still shows some spotting. For adults, the most reliable field mark is the underpart pattern: Arrowhead Piculet has white underparts with a scaly look, while Spotted Piculet shows brown to rufous underparts with bold black and white spots. Both species have a black cap with a red patch on the male's forehead, but their upperpart and underpart patterns, as well as range, help separate them. Range is also a strong clue: Arrowhead Piculet is found in Suriname and adjacent Guianas, while Spotted Piculet is endemic to Brazil.

Identification tips

1. Juvenile crown: Juvenile Arrowhead Piculet has a plain brown crown, while juvenile Spotted Piculet is duller but retains some spotting; use this for birds lacking adult cap pattern.
2. Juvenile upperparts: Arrowhead Piculet juveniles show browner, more heavily barred upperparts; Spotted Piculet juveniles are dull but not as distinctly barred.
3. Adult underparts: Arrowhead Piculet has white underparts with a brownish buff tinge and a scaly appearance from dark feather fringes; Spotted Piculet has light to dark brown underparts, often with a rufous wash, and bold black and white spots. This is the most reliable adult field mark.
4. Upperparts (adults): Arrowhead Piculet's upperparts are olive brown with blackish wedge-shaped centers and thin black bars, plus a white spot near the feather tip; Spotted Piculet's are darker brown with black and white tips and a paler rump.
5. Flight feathers: Arrowhead Piculet's flight feathers are brown with light buffy edges, especially on secondaries and tertials; Spotted Piculet's are dark brown with buff or cinnamon-buff edges and tips.
6. Tail pattern: Both have blackish tails with white on the inner webs of the innermost pair and white on the outer feathers, but Spotted Piculet's outer two pairs have a white patch near the end, while Arrowhead's have a white stripe on the outer webs.
7. Cap and forehead: Both males have a black cap with a red forehead patch and white spots elsewhere; females lack the red. This is not diagnostic between species but helps with sexing.
8. Facial pattern: Both species have a mostly dark brown face with white feather tips and a white line behind the eye (Arrowhead). Not a strong separator.
9. Chin/throat/neck: Arrowhead Piculet shows whitish with blackish bars; Spotted Piculet has a variable black and white pattern.
10. Rump: Arrowhead's rump is plainer; Spotted's is paler than the rest of the upperparts.
11. Geographic range: If seen in Suriname or the Guianas, expect Arrowhead Piculet; in Brazil, expect Spotted Piculet. This is often the deciding factor.
12. Sex differences: In both species, only males have the red forehead patch; this does not help with species separation but is useful for sexing.
13. Size: Both species are the same size (9–10 cm); do not use size for identification.
14. Behavior: No behavioral differences are noted; do not rely on behavior for separation.
15. Voice: No vocal differences are described in the sources; do not use voice for separation.

Size

Both species are nearly identical in size, each about 9–10 cm (3.5–3.9 in) in length. Arrowhead Piculet weighs 11–16 g, while Spotted Piculet's weight is not specified but is likely similar. Size is not a reliable separator in the field.

Plumage

• Juveniles: Arrowhead Piculet juveniles have a plain brown crown and browner, more heavily barred upperparts, with duller and less distinct underpart patterning. Spotted Piculet juveniles are generally duller than adults, with less distinct spots, but still show some spotting on the underparts.

• Adults: Both species have a black cap with a red forehead patch in males (absent in females), and a dark brown face with white feather tips. Arrowhead Piculet's upperparts are olive brown with blackish wedge-shaped centers and thin black bars, with a white spot near the feather tips; Spotted Piculet's upperparts are darker brown with black and white tips and a paler rump. The Arrowhead's underparts are white with a brownish buff tinge and a scaly look from brownish-black feather fringes, while Spotted Piculet has light to dark brown underparts, often rufous-tinged, with large, bold black and white spots. Arrowhead's flight feathers are brown with light buffy edges, while Spotted's are dark brown with buff or cinnamon-buff edges and tips. Tail patterns are similar but Spotted Piculet's outer tail feathers have a white patch near the end, while Arrowhead's have a white stripe on the outer webs.

Behaviour

No behavioral differences are noted in the sources that would reliably separate these two species in the field.

Habitat

Arrowhead Piculet is found in Suriname and possibly French Guiana and Guyana, while Spotted Piculet is endemic to Brazil. Habitat overlap is unlikely, so geographic context is a strong clue: if you are in Brazil, Spotted Piculet is the default; in Suriname or the Guianas, Arrowhead Piculet is expected.