A systematic appraisal of the types of ten species of Otostigmus (Parotostigmus) (Scolopendromorpha, Scolopendridae, Otostigminae)
Author
Chagas-Jr, Amazonas
text
Zootaxa
2016
4147
1
36
58
journal article
10.11646/zootaxa.4147.1.2
b0e2f296-95a9-4ffc-92d8-ca46a49997c2
1175-5326
262564
4CBE20C2-2851-4B16-8626-26C373413E1A
Otostigmus
(
Parotostigmus
)
scabricauda
(
Humbert & Saussure, 1870
)
(
Figures 26–33
)
Branchiostoma scabricaudus
Humbert & Saussure, 1870
: 203
;
Saussure & Humbert, 1872
: 121
, Pl. 6,
Fig. 15
;
Otostigmus appendiculatus
Porat, 1876
: 23
(Synonymised by
Attems, 1930
);
Branchiotrema scabricauda
Kohlrausch, 1881
: 75
;
Otostigma brasiliense
Meinert, 1886
: 119
(Synonymised by
Attems, 1930
);
Otostigmus scabricaudus
Kraepelin, 1903
: 123
, Fig. 61;
Otostigmus
(
Parotostigmus
)
scabricauda
Attems, 1930
: 159
, fig. 191;
Bücherl, 1974
: 117
;
Otostigmus
(
Androstigmus
)
scabricauda
Bücherl, 1940
: 221
; 1942: 58.
Type
material examined.
Holotype
NHMW
1015
,
Rio de Janeiro
, 1864,
Tosh
leg.
Diagnosis.
Tergites 13–21 with scattered tubercles; tergites 5–20 more densely tuberculate laterally. Sternites 2–20 with a rounded anterior medial depression; sternites 4–13 with two small longitudinal rounded depressions in the middle; sternites 2–15 with three small transversal rounded depressions at the posterior margin. Legs 2–16 with one tarsal spur. Prefemur of ultimate legs of males with a digitiform appendix slightly shorter than the prefemur, and slightly flattened dorsoventrally; digitiform appendix with a tuft of hairs at the tip.
Redescription (male).
Length:
70 mm
from the anterior margin of the cephalic plate to the posterior margin of tergite 21. Antennae with 17 articles, the two basal articles glabrous. Cephalic plate smooth, without sutures and depressions, wider than long (
Fig. 26
). Coxosternal tooth-plates wider than long; with 4+4 teeth, the two inner teeth closer to each other than to the external teeth; with a strong seta in the middle of each tooth-plate (
Fig. 28
). Coxosternite with transverse and short longitudinal sutures at the base of the tooth-plates; the transverse suture is bifurcate laterally (
Figs 27 and 28
). Forcipular trochanteroprefemoral process larger than tooth-plates, the margin with one medial denticle (
Fig. 28
).
Tergite 1 overlying the posterior margin of the cephalic plate; tergites 1–4 without sutures; tergites 5–20 with complete paramedian sutures; tergites 5–21 marginate; tergites 1–12 smooth; tergites 13–21 with scattered tubercles; the number of tubercles on the tergites gradually increases from tergites 13–21; tergites 5–20 with gradually increasing lateral longitudinal rugosity; tergite 21 longer than wide, the posterior margin slightly convex; with slight longitudinal depression (
Fig. 29
).
Sternites smooth, longer than wide; sternites 2–20 with a rounded anterior medial depression; sternites 4–13 with two small longitudinal rounded depressions in the middle; sternites 2–15 with three small transversal rounded depressions at the posterior margin; sternite 21 shorter than the preceding sternite, converging posteriorly; posterior margin of sternite 21 slightly concave and with a weak longitudinal depression (
Fig. 30
).
Coxopleuron without spines, slightly prolonged posteriorly; pore-field covers almost all coxopleuron, only the posteromedian and posterolateral end poreless (
Fig. 30
).
Legs 1 with one femoral, one tibial and two tarsal spurs; with two accessory pretarsal spines, and legs 2–16 with one tarsal spur. Prefemur of ultimate legs with a digitiform appendix slightly shorter than the prefemur (
Fig. 31
); with a tuft of hairs at the tip (
Fig. 32
) and slightly flattened dorsoventrally (
Fig. 33
).
FIGURES 26–28
.
Otostigmus
(
P
.)
scabricauda
. Type NHMW 1015, male.
26
. Cephalic plate.
27
. Forcipular segment and sternite 1.
28
. Forcipular coxosternal tooth-plates and trochanteroprefemoral process. Scale bars 1 mm.
Remarks.
O. scabricauda
was briefly described by
Humbert and Saussure (1870)
in the genus
Branchiostoma
Newport, 1845
. Eleven years later,
Kohlrausch (1881)
transferred it to the genus
Branchiotrema
Kohlrausch, 1878
.
Kraepelin (1903)
redescribed
O. scabricauda
in detail and returned it to
Otostigmus
. Kraepelin’s redescription is very similar to this description of the
type
of
O. scabricauda
, so I think that he described the same specimen.
O. scabricauda
is widely distributed in
Brazil
, and was also recorded from
Colombia
,
Ecuador
and
Peru
(
Bucherl 1974
).
Chagas-Jr
et al
. (2014)
excluded the Colombian record because of misidentifications and lack of the species in the examined collections.
O. scabricauda
is one of the several species of
Parotostigmus
in which the males have a digitiform appendix on the prefemur of the ultimate legs. As it was one of the first known species with this sexually dimorphic character, all other
Otostigmus
subsequently described with this feature were compared to it. However, as showed by
Chagas-Jr (2012)
, the digitiform appendix is not exclusive to Brazilian
Otostigmus
, being also present in the males of other Neotropical and West African species; and at least among Brazilian
Otostigmus
, the morphology of the digitiform appendix is species-specific (for more details see
Chagas-Jr 2012
). The digitiform appendix of the
holotype
of
O. scabricauda
is almost the same length as the prefemur, slightly flattened dorsoventrally, and with a tuft of hairs right at the tip. Its tip is rounded. In studied specimens of
O. scabricauda
from
Rio de Janeiro
, the
type
locality, the digitiform appendix is similar to the
holotype
in shape and length, but the tuft of hairs emerges from a terminal concavity. The morphology of this appendix and its function need further investigation.