38
group 1
J-,
group 2
,6 I
group 3
o
0.1
0.2
0.3
0.4
ra.t:io p d / s l
Fig. 14. Graph illustrating the gap between the means of the ratio pdlsl (peduncle/standard length) of groups I & 2, and 2 & 3. Group I
included 98 specimens of six species with short peduncles; group 2 included 67 specimens of six species with intermediate peduncles; and group
3 included 286 specimens of 15 species with long peduncles. For each group, the means of the averages (vertical lines), a pooled within-group
standard deviation on each side of the mean (rectangle), and the range of the individual values (horizontal line ) are shown. The Streptocephalus
species included in the graph are: group 1, rothschildi, lamellifer, sudanicus, bidentatus, macrourus & vitreus; group 2, sealii, similis, cafer,
indistinctus, trifidus & sp. A; group 3, dichotomus, cladophorus, neumanii, proboscideus, ovamboensis, rubricaudatus, torvicornis, guzmani,
mattoxi, antillensis, dorothae, linderi, mackini, potosinensis & texanus. For data of the material see Maeda-Martinez et al. (1994; this volume).
Chihuahua, Coahuila, Durango, Nuevo Le6n, Oaxaca, San Luis Potosi, and Tamaulipas; and from the
Caribbean islands of Barbuda and Desirade (Packard
1883; Creaser, 1930; Mackin, 1942; Dexter, 1959;
Moore, 1966; Belk, 1975,1983; Spicer, 1982; MaedaMartinez, 1991).
Key to the New World species of
Streptocephalus
The sequence of the taxa does not necessarily show
their phylogenetic relationships. The key is limited to
adult males.
1a. Thumb with spur; finger with teeth ......... 2
1 b. Thumb without spur; finger without teeth.
S. kargesi Spicer (Fig. 1)
2a. Cercopods spinose on distal half ........... 3
2b. Cercopods setose along inner and lateral borders
........................................ 4
3a. Two teeth on finger; genitalia with a pair of linguiform outgrowths at outward base of penes
S. sealii Ryder (Fig. 2)
3b. Three teeth on finger, genitalia without a pair of
linguiform outgrowths ..................... .
S. similis Baird (Fig. 3)
4a. Genitalia with a pair of linguiform outgrowths at
the outward base of penes .................. .
S. woottoni Eng, Belk & Eriksen (Fig. 4)
4b. Genitalia without a pair of linguiform outgrowths ................................. 5
5a. Dorsal margin of thumb crenate or spinose
......................................... 6
5b. Dorsal margin of thumb inerm ............. 8
6a. Dorsal margin of thumb crenate ............ .
S. mattoxi n.sp. (Fig. 6)
6b. Dorsal margin of thumb spinose ........... 7
7a. Finger with a single hump-like tooth; dorsolateral side of base of hand, with long anteriorly
curved process ............................ .
S. moorei Belk (Fig. 11)
7b. Finger with two teeth; dorsolateral side of base
of hand, without a long process ............. .
S. antillensis Mattox (Fig. 7)
group 1
J-,
group 2
,6 I
group 3
o
0.1
0.2
0.3
0.4
ra.t:io p d / s l
Fig. 14. Graph illustrating the gap between the means of the ratio pdlsl (peduncle/standard length) of groups I & 2, and 2 & 3. Group I
included 98 specimens of six species with short peduncles; group 2 included 67 specimens of six species with intermediate peduncles; and group
3 included 286 specimens of 15 species with long peduncles. For each group, the means of the averages (vertical lines), a pooled within-group
standard deviation on each side of the mean (rectangle), and the range of the individual values (horizontal line ) are shown. The Streptocephalus
species included in the graph are: group 1, rothschildi, lamellifer, sudanicus, bidentatus, macrourus & vitreus; group 2, sealii, similis, cafer,
indistinctus, trifidus & sp. A; group 3, dichotomus, cladophorus, neumanii, proboscideus, ovamboensis, rubricaudatus, torvicornis, guzmani,
mattoxi, antillensis, dorothae, linderi, mackini, potosinensis & texanus. For data of the material see Maeda-Martinez et al. (1994; this volume).
Chihuahua, Coahuila, Durango, Nuevo Le6n, Oaxaca, San Luis Potosi, and Tamaulipas; and from the
Caribbean islands of Barbuda and Desirade (Packard
1883; Creaser, 1930; Mackin, 1942; Dexter, 1959;
Moore, 1966; Belk, 1975,1983; Spicer, 1982; MaedaMartinez, 1991).
Key to the New World species of
Streptocephalus
The sequence of the taxa does not necessarily show
their phylogenetic relationships. The key is limited to
adult males.
1a. Thumb with spur; finger with teeth ......... 2
1 b. Thumb without spur; finger without teeth.
S. kargesi Spicer (Fig. 1)
2a. Cercopods spinose on distal half ........... 3
2b. Cercopods setose along inner and lateral borders
........................................ 4
3a. Two teeth on finger; genitalia with a pair of linguiform outgrowths at outward base of penes
S. sealii Ryder (Fig. 2)
3b. Three teeth on finger, genitalia without a pair of
linguiform outgrowths ..................... .
S. similis Baird (Fig. 3)
4a. Genitalia with a pair of linguiform outgrowths at
the outward base of penes .................. .
S. woottoni Eng, Belk & Eriksen (Fig. 4)
4b. Genitalia without a pair of linguiform outgrowths ................................. 5
5a. Dorsal margin of thumb crenate or spinose
......................................... 6
5b. Dorsal margin of thumb inerm ............. 8
6a. Dorsal margin of thumb crenate ............ .
S. mattoxi n.sp. (Fig. 6)
6b. Dorsal margin of thumb spinose ........... 7
7a. Finger with a single hump-like tooth; dorsolateral side of base of hand, with long anteriorly
curved process ............................ .
S. moorei Belk (Fig. 11)
7b. Finger with two teeth; dorsolateral side of base
of hand, without a long process ............. .
S. antillensis Mattox (Fig. 7)