Reinert et al. • NEST AND EGGS OF THE MARSH ANTWREN 
289 
TABLE 2. Nest measurements of the Marsh Antwren (Stymphalornis acutirostris) in Guaratuba Bay, Parana, 
southern Brazil. 
Nest characteristic 
Nest height, mm 
Incubation chamber depth, mm 
Minimum external diameter, mm 
Maximum external diameter, mm 
Minimum internal diameter, mm 
Maximum internal diameter, mm 
Nest material volume, cm 3 
Incubation chamber volume, cm 3 
Total dry mass, g 
Range 
Mean ± SD 
144 
40.0-130.0 
68.5 ± 13.7 
142 
20.0-80.0 
44.7 ± 9.2 
145 
35.0-90.0 
65.9 ± 9.5 
145 
53.1-120.0 
79.7 ±11.3 
145 
25.0-57.5 
45.3 ± 5.6 
145 
30.4-75.0 
54.7 ± 6.9 
138 
26.7-527.8 
156.1 ± 76.4 
138 
34.2-147.3 
72.7 ± 22.8 
39 
1.5-8.7 
3.8 ± 1.2 
attachment categories (H): top lip (n = 53), 
bottom multiple (vertical) (n = 22), or both 
simultaneously (n = 74). Twenty of the top lip 
nests were attached to a fork. 26 to parallel 
vegetation, and three were attached to the 
vegetation above the nest. Four top lip nests were 
attached to only one horizontal stem instead of 
wo horizontal parallel stems (Fig. IE), which 
does not fit any previously described category. 
Some nests of the Marsh Antwren could not be 
assigned to only one nest attachment category, 
using the categories lateral and single horizontal 
top lip ( n = 22) at the same time. 
The nests of the Marsh Antwren following S&P 
were low cup (n = 113) or a high cup (n = 29). 
The categories of support type (S&P) were fork (n 
= 46), lateral (n = 22), pensile (n = 3), and 
lateral and fork at the same time (n = 52) with the 
latter combination being previously unreported. 
The four nests that were attached to only one 
horizontal stem also do not Fit any described 
category (H or S&P). for which we propose the 
category: single horizontal top lip. 
Nests varied greatly in all measurements 
including dry weight, and volume ot nest material 
and incubation chamber (Table 2). The height 
TABLE 3. Frequencies (percent in parentheses) of plant species used as support for nests of the Marsh Antwren 
(Stymphalornis acutirostris ) in Guaratuba Bay. Parana, southern Brazil. Columns 1. 2, 3. and 4 refer to nests supporte y 
°ne. two. three, or four plant species, respectively. 
Number of supporting plant species 
Species 
Plant type 
1 oial frequency - 
(n = 157) 
1 tn = 95) 
2 (n = 50) 
3 (n = 10) 
4 (n = 2) 
rosticlium danaefolium 
herb 
49 (31.2) 
38 (40.0) 
10 (20.0) 
1 (10.0) 
Oadium jamaicense 
herb 
35 (22.3) 
19 (20.0) 
14 (28.0) 
2 (20.0) 
2 (100) 
hirew robusta 
herb 
29 (18.5) 
10 (10.5) 
11 (22.0) 
6 (60.0) 
''‘ hoenoplectus caUfbmicus 
herb 
26 (16.6) 
18 (36.0) 
6 (60.0) 
2(100) 
Cnnum americanum 
herb 
17 (10.8) 
10 (20.0) 
5 (50.0) 
2(100) 
1 Qlophyllum brasiliense 
tree 
14 (8.9) 
7 (7.4) 
7 (14.0) 
2 (20.0) 
2 (100) 
hinndorus grandiflorus 
herb 
12 (7.6) 
3 (3.2) 
5 (10.0) 
guncularia racemosa 
tree 
12 (7.6) 
4 (4.2) 
7(14.0) 
1 (10.0) 
Siruthanthus vulgaris 
mistletoe 
9 (5.7) 
2 (2.1) 
6 (12.0) 
1 (10.0) 
fulipariti pemamhucense 
shrub 
7 (4.5) 
5 (5.3) 
2 (4.0) 
S'igmaphyllon ciliatum 
V igna luieola 
liana 
5 (3.2) 
2 (2.1) 
3 (6.0) 
1 (10.0) 
liana 
4 (2.5) 
1 (l.D 
2 (4.0) 
Commeltna diffusa 
herb 
3 (1.9) 
1 (2-0) 
3 (30.0) 
Typha domingensis 
herb 
3 (1.9) 
2(2.1) 
Adenostemma brasilianum 
herb 
2(1.3) 
1 (2.0) 
1 (10.0) 
^Onicum cf. mertensii 
herb 
2(1.3) 
1 (l.D 
1 (10.0) 
Rhizophora mangle 
tree 
2 (1.3) 
1 (l.D 
1 (2.0) 
'\nnona glabra 
tree 
1 (0.6) 
1 (2.0) 
Knlboseboenus robust us 
herb 
1 (0.6) 
I (2-0) 
