Type locality. Federal Highway 45, 10 mi N Jimenez,
Chihuahua, Mexico.
Material examined. Paratypes DB 062, 2 cf' cf' 14.4,
15.0 mm, 2 Cj) Cj) 12.0, 12.2 mm, and additional 15 Cj)
Cj) examined by D. Belk.
Diagnosis. Male. Peduncle of distal outgrowth of long
type, without pulvinus; a large conical protuberance,
ventrally directed, situated on inner side just at first
geniculation of peduncle; a series of c. 6 small conical protuberances, variable in size, situated on inner
side of distal part; a series of c. 8 vermiform protuberances on lateral side of distal part of peduncle,
near base of hand; dorsolateral side of base of thumb
with long subacuminate curved process, anterodorsally
directed, then curved ventrally; spur broad at base, narrow at middle, apex with dorsal rounded protuberance,
ending in subacuminate prolongation, anteroventrally
directed; lateral lamella with acute angle between distal
part of thumb and spur; inner lamella medioventrally
produced, forming a cavity; thumb very long, proximal two third slightly curved upward, last third curved
most; apex acuminate; dorsal margin with series of
unequal spiniform structures; finger bigeniculate, inner
dorsal side of proximal part, with single hump-like
tooth anteromedially directed; apex acuminate, with
subapical digitiform structure, ventrolaterally directed; frontal appendage short, distal part with a pair of
conical protuberances, in ventrolateral position; genitalia without linguiform outgrowths; cercopods separate, setose along inner and lateral borders; anus terminal.
Female. Ovaries biramous, variably extending
from thoracic segments 9-11 to abdominal segments
6-8; cysts sphaerical, ornamented by ribs forming
polygonal areas.
Differential diagnosis. Within the torvicornis group,
S. moorei exhibits the most complex distal antennal
outgrowth. (1) The large conical protuberance on the
inner side at the first geniculation of the peduncle, (2)
the series of c. 8 vermiform protuberances on the lateral
side of the distal part of the peduncle, and (3) the long
curved process on the dorsolateral side of the base of
the thumb, are unique features of S. moo rei. Other distinctive characters are the single hump-like tooth on the
finger, the subapical digitiform structure on the apex
of the finger, and the pair of conical protuberances,
ventrolaterally situated on the frontal appendage. For
a comparison with the other American species with
35
a spinose thumb, see the differential diagnosis of S.
antillensis.
Distribution. S. moorei is known only from its type
locality.
Streptocephalus potosinensis n. sp.
(Fig. 12 A-E)
Streptocephalus sp. D. Maeda-Martinez et ai. (1994;
this volume).
Type material. Holotype cf' 16.9 mm, allotype Cj) 15.1
mm, USNM 259680, 259681. Paratypes 20 cf' cf' 15.8
(l1.9-18.2)mm, 11 Cj)Cj) 14.5 (12.6-16.1)mm, USNM
259682-3, DB 725, collected 3 July 1961 by E. Liner.
Type locality. Pond at 6.1 km E Ciudad del Mar, San
Luis Potosi, Mexico.
Diagnosis. Male. Peduncle of distal outgrowth of long
type, without pulvinus, with a series of about 10 conical
protuberances variable in size, situated on inner side of
distal part; inner dorsal side of base of hand with stout
spiniform structure, anteriorly directed; spur bladeshaped and finishing subacuminate; lateral lamella
with an acute angle between distal part of thumb and.
spur; inner lamella medioventrally produced forming
a cavity; distal part of thumb, inerm, geniculate, with
ventral elbow, apex acuminate; finger bigeniculate,
two teeth on inner dorsal side of proximal part; distal
tooth broad at base, dorsally spatulate; proximal one
larger, subacuminate, anteromedially oblique; finger
at first geniculation with broad and prominent dorsal
lamella, narrow at second geniculation; apex of finger acuminate, armed with a subapical lateral lamella,
undulate at its anteroventral margin.
Female. Ovaries biramous, variably extending
from thoracic segment 7 -8 to abdominal segments 4-5;
brood pouch ends at segment 4; cyst sphaerical ornamented by ribs forming polygonal areas.
Differential diagnosis. As mentioned above, S. potosinensis exhibits a number of similarities with S. linderi
and S. texanus. For differences among these species,
see differential diagnosis of S. linderi.
Distribution. S. potosinensis n.sp. is known only from
its type locality.
Chihuahua, Mexico.
Material examined. Paratypes DB 062, 2 cf' cf' 14.4,
15.0 mm, 2 Cj) Cj) 12.0, 12.2 mm, and additional 15 Cj)
Cj) examined by D. Belk.
Diagnosis. Male. Peduncle of distal outgrowth of long
type, without pulvinus; a large conical protuberance,
ventrally directed, situated on inner side just at first
geniculation of peduncle; a series of c. 6 small conical protuberances, variable in size, situated on inner
side of distal part; a series of c. 8 vermiform protuberances on lateral side of distal part of peduncle,
near base of hand; dorsolateral side of base of thumb
with long subacuminate curved process, anterodorsally
directed, then curved ventrally; spur broad at base, narrow at middle, apex with dorsal rounded protuberance,
ending in subacuminate prolongation, anteroventrally
directed; lateral lamella with acute angle between distal
part of thumb and spur; inner lamella medioventrally
produced, forming a cavity; thumb very long, proximal two third slightly curved upward, last third curved
most; apex acuminate; dorsal margin with series of
unequal spiniform structures; finger bigeniculate, inner
dorsal side of proximal part, with single hump-like
tooth anteromedially directed; apex acuminate, with
subapical digitiform structure, ventrolaterally directed; frontal appendage short, distal part with a pair of
conical protuberances, in ventrolateral position; genitalia without linguiform outgrowths; cercopods separate, setose along inner and lateral borders; anus terminal.
Female. Ovaries biramous, variably extending
from thoracic segments 9-11 to abdominal segments
6-8; cysts sphaerical, ornamented by ribs forming
polygonal areas.
Differential diagnosis. Within the torvicornis group,
S. moorei exhibits the most complex distal antennal
outgrowth. (1) The large conical protuberance on the
inner side at the first geniculation of the peduncle, (2)
the series of c. 8 vermiform protuberances on the lateral
side of the distal part of the peduncle, and (3) the long
curved process on the dorsolateral side of the base of
the thumb, are unique features of S. moo rei. Other distinctive characters are the single hump-like tooth on the
finger, the subapical digitiform structure on the apex
of the finger, and the pair of conical protuberances,
ventrolaterally situated on the frontal appendage. For
a comparison with the other American species with
35
a spinose thumb, see the differential diagnosis of S.
antillensis.
Distribution. S. moorei is known only from its type
locality.
Streptocephalus potosinensis n. sp.
(Fig. 12 A-E)
Streptocephalus sp. D. Maeda-Martinez et ai. (1994;
this volume).
Type material. Holotype cf' 16.9 mm, allotype Cj) 15.1
mm, USNM 259680, 259681. Paratypes 20 cf' cf' 15.8
(l1.9-18.2)mm, 11 Cj)Cj) 14.5 (12.6-16.1)mm, USNM
259682-3, DB 725, collected 3 July 1961 by E. Liner.
Type locality. Pond at 6.1 km E Ciudad del Mar, San
Luis Potosi, Mexico.
Diagnosis. Male. Peduncle of distal outgrowth of long
type, without pulvinus, with a series of about 10 conical
protuberances variable in size, situated on inner side of
distal part; inner dorsal side of base of hand with stout
spiniform structure, anteriorly directed; spur bladeshaped and finishing subacuminate; lateral lamella
with an acute angle between distal part of thumb and.
spur; inner lamella medioventrally produced forming
a cavity; distal part of thumb, inerm, geniculate, with
ventral elbow, apex acuminate; finger bigeniculate,
two teeth on inner dorsal side of proximal part; distal
tooth broad at base, dorsally spatulate; proximal one
larger, subacuminate, anteromedially oblique; finger
at first geniculation with broad and prominent dorsal
lamella, narrow at second geniculation; apex of finger acuminate, armed with a subapical lateral lamella,
undulate at its anteroventral margin.
Female. Ovaries biramous, variably extending
from thoracic segment 7 -8 to abdominal segments 4-5;
brood pouch ends at segment 4; cyst sphaerical ornamented by ribs forming polygonal areas.
Differential diagnosis. As mentioned above, S. potosinensis exhibits a number of similarities with S. linderi
and S. texanus. For differences among these species,
see differential diagnosis of S. linderi.
Distribution. S. potosinensis n.sp. is known only from
its type locality.