Taxonomic review of the Amazonian millipede genus Parastenonia Hoffman, 1977 and description of a new species from iron-ore caves (Polydesmida: Chelodesmidae)
Author
Bouzan, Rodrigo S.
Author
Iniesta, Luiz Felipe M.
Author
de Souza, Claudio A. R.
Author
Zampaulo, Robson A.
Author
Brescovit, Antonio D.
text
Journal of Natural History
2020
2020-04-28
53
45 - 46
2781
2799
http://dx.doi.org/10.1080/00222933.2020.1749956
journal article
10.1080/00222933.2020.1749956
1464-5262
4608825
CCBEED10-DCB4-48C9-A71D-CED3462DD72A
Family
CHELODESMIDAE
Cook, 1895
Subfamily
CHELODESMINAE
Cook, 1895
Tribe
Priodesmini
Hoffman, 1977
Genus
Parastenonia
Hoffman, 1977
Parastenonia
Hoffman, 1977: 449
–
459
.
Type
species:
Priodesmus aurae
Schubart, 1947
[=
Priodesmus parae
Cook 1895
], by original designation.
Hoffman 1980: 152
;
Shelley et al. 2000: 120
.
Diagnosis
Males of
Parastenonia
differ from those of other chelodesmid genera by the combination of the following characters: metaterga granular and crossed by a transversal sulcus (
Figure 4
(d)), as in
Cypraeogona
,
Cayenniola
,
Cearodesmus
and
Brasiloschubartia
, from which however this genus differs in the shape of the gonopod; lateral edge of paranota trilobed by the presence of two deep sinuses (
Figure 4
(a,b)), as in
Priodesmus
and
Stenonia
, (see
Attems 1938
, figs 68
–
69;
Jeekel 1963
, figs 30
–
32) however without modifications on the walking legs; gonocoxae large, with a dorsal field of setae; a long slender acuminate process on acropodite and an elongated prefemoral process (
Figure 9
(a,b)).
Redescription
General measurements.
Body length between 32.30 mm (female of
P. parae
) and 22.60 mm (male of
P. carajas
sp. nov.
).
Colouration (in 70% ethanol).
Variable among species, ranging from reddish brown to ochre.
Head.
With scattered tubercles, some of which bearing setae (
Figure 2
(a
–
f)); shape of the
incisura lateralis
suboval. Antenna elongated, about 1.5x the width of midbody ring (
Figure 3
(a
–
d)).
Body rings.
Integument with small tubercles, without setae (
Figure 4
(a,b,d,e)). A transversal groove on the metazonite. Collum with the anterior border arched and posterior border straight. Spiracles oval. Sternites without modifications. Ozopores on trunk rings: 5, 7, 9, 10, 12, 13, 15
–
19 (the standard polydesmid pore formula), located at the tip of the intermediate paranotum; and surrounded by peritremata. Paranota: prominent and long, wide, covering part of the legs, without setae on the edges. Paranota divided laterally into three lobes:
-pro; -meso
and
-meta
(
Figure 4
(a,b)). Telson: triangular, wide and with tubercles (
Figure 4
(e)). Epiproct with five pairs of macrosetae projecting through the tubercles on the dorsal side and two pairs in the apical region; paraproct with two macrosetae on each valve; hypoproct with two macrosetae.
Legs.
Granulated; scattered setae along the entire surface (
Figure 4
(c)).
Male sexual characters.
Gonopore located on the coxae of the legs of the third body ring, coxae rounded, with a large apical pore (
Figure 9
(a)). Gonopod aperture large, rectangular-shaped; posterior edge slightly folded (
Figures 8
(a
–
b) and 9(b)). Gonopods: coxae (
Cx
;
Figures 6
(a) and 9(c,d)) equivalent to about half the length of the telopodite, without spiniform process, with several setae on dorsal side; coxae dorsally prominent in ectal view. Cannula (
C
;
Figure 9
(e)) robust and hook-shaped. Spermatic groove: runs along the mesal side of the acropodite in the entire length (
SG
;
Figure 6
(b)). Telopodite elongated, divided into two parts: the prefemoral region (
Figure 9
(d)) and the femoral region (
Figure 9
(d)). Prefemoral process (
Figure 9
(d)): branch long with stretch marks (
Figure 9
(f)). Acropodite long divided into two parts, the larger central branch is the solenomere carrying the spermatic groove with a thin elongated branch, rising proximally from the femoral region (
Figure 9
(d)).
Female sexual characters.
Cyphopods elongated, situated directly behind the second pair of legs on the third body ring; composed of valves and operculum, all densely setose; two valves joined by a membrane and operculum apically, appressed against both larger
valves (
Figures 6
(c
–
f) and 10(a
–
e)). A small projection of the valves with S-shaped curvature in the intermediate membrane (
Figures 6
(c,d) and 10(a)).
Included species
Two species:
Parastenonia parae
(
Cook, 1895
)
and
P. carajas
sp. nov.
Distribution
Known only from Amazon rainforest in the state of Pará,
Brazil
(
Figure 11
).