lNi.yriapodolo9ica

A SERIES OF OCCASIONAL PAPERS PUBUSHED AT RADFORD UNIVERSITY

ISSN 0163-5395

Vol- 1, No. 3

September 15, 1979

Chelodesmid studies. XV. The identity and status of
the generic name Strongyhsomides Attems^

BY RICHARD L. HOFFMAN

In an early paper describing new polydesmoids belonging to the Hamburg
Museum, Graf Attems (1901) proposed to divide the genus Lepfodesmus into
three subgenera: the nominate subgenus, Rhachidomorpha de Saussure, and
Strongy/osom/des, proposed as new. These taxa have had erratic subsequent
histories. Leptodesmus itself became a very large and heterogeneous aggregation
whose dismemberment and reclassification has only recently been undertaken.
Rhachidomorpha as conceived by Attems was based on the characteristics of a
Brasilian species he misidcntified as R. tarascus (dc Saussure, 1859); the two
forms are in fact not even confamilial, Attems subsequently realized this error and
in 1931 provided the new generic name Corna/atus for the Brasilian species,
which, inexplicably, he continued to call tarascus. Corna/atus automatically
became a junior objective synonym of Rhachidomorpha, of which tarascus is the
tyi>e species by monotypy. Some years later (1938) Attems renamed the Brasilian
species as Cornalatus permutatus so that it finally acquired its own identity even
though too late to validate the generic name. “Corna/atus” permutatus does
require separate generic status, but resolution of that problem is deferred for a
later occasion.

This leaves Strongy/osomides, based on a small Brasilian chelodesmid —
named petropoUtes after its type locality — in which the paranota are reduced to
small lateral ridges and the collum is narrower than the head (a result of its lateral
ends being directed ventrad). in 1926 Attems elevated the name to generic rank,
and in 1931 he included it in a key to chelodesmoid genera and provided also a
diagnosis and gonopod drawing. Lastly, in 1938 Attems gave a formal treatment of
the genus in Lief. 69 of the Tierreich series, at which time a second species,
Leptodesmus ci/lindricus (Brolemann, 1902) was added. Subsequently, aside from
passing mention in several papers by Otto Schubart, Strongy/osomides has
languished in obscurity.

‘A contributbn from studies supported by gremt DEB 77-13471 from the National Science Foundation. All
views expressed are those of the author and not of the Foundation.

Scanned with permission by Virginia Tech Insect Systematics Group 2014 (www.jointedlegs.org)

20

M\^riapodologica

One might justly write “well-deserved obscurity” because the exact status of S.
petropolites has never been adequately established. The original description was
reasonably detailed, and included some drawings of gonopod structure. The
latter, unfortunately, were prepared from an aspect which prevented them from
being compared with gonopods of other chelodesmids drawn from the standard
medial position. Attems had removed both gonopods from the holotype and
flattened them into a dorsal orientation in his microscope preparation, so that all of
his figures were drawn from this single atypical position. In 1979 1 was fortunate in
locating the poorly made and labeled preparation (the original mounting medium
of which had almost entirely dried and disappeared) and was able to salvage the
gonopods in fairly good condition. Thus an evaluation of Sfrongyfosomides
became possible nearly eight decades after the name was first published.

Although the genus cannot be confidently assigned to a particular tribe at this
time, it nonetheless is desirable to establish Strongy^losomides as a valid and easily
recognizable taxon composed of numerous species described from southeastern
Brasil.

The material on which this paper is based is located in the Zoologisches
Museum Hamburg and I express my thanks to Dr, Gisela Rack for placing the
collections under her care at my disposal.

Strongylosomides.

Sfrongy/osomides Attems, 1901, Mitt. Naturh. Mus. Hamburg, vol. 13, p. 89.
Proposed as a subgenus of Leptodesmus. Monobasic with a new sp>ecies, L,
(S.) petropolites, from Brasil.

Sfrongyfosomides (as genus): Attems, 1931, Zoologica, vol. 30, heft 79, p. 51; 1938,
Das Tierreich, lief, 69, p, 97. — Schubart, 1955, Arq. Mus. Nac. Brasil, vol. 42,
p. 510.

Diagnosis: Very small to small chelodesmids (length of males ca. 12-30 mm) in
which the paranota are reduced to low longitudinal ridges or, if larger, strongly
depressed ventrad imparting a strongly convex aspect to the animal, their anterior
and lateral edges forming a continuous even curve; ozoporcs in normal sequence,
opening laterally in ovid posterior expansion of peritremata; metaterga smooth
and polished, without transverse sulcus. Epiproct small, conical, apically
somewhat decurved; paraprocts and hypoproct unmodified. Pleurosternal
carinae usually present and visible as far back as 17th segment. Sterna posterior to
gonopods broad, flattened, glabrous or nearly so, without subcoxa! spines or
other modification. Legs relatively short and stout, usually unmodified but
subtarsal tibia) pads and apical prefemoral knobs present in a few species. Color
uniformly dark maroon to black, without colorful paranotal or median dorsal
spots.

Sterna of segments 4, 5, and 6 of males with paramedian conical or somewhat
transverse processes, their form varying in individual species. Legs of these
segments without femoral glands or processes. Gonopods of moderate size, set in
oval aperture. No trace of median sternal remnant, coxae abut along a long
sinuous line of contact (Fig. 6). Acute slender coxa) apophysis present, with

Hoffman: Strongs/hsomides

21

Fig. 1. Strongytosomides petropoHtes (Attems). Telopodite of left gonopod of
male holotype, mesal aspect. Scale represents 1.0 mm.

(usually) a single dorsal macroseta at its base; no setae subtending cannula on
medium side. Cannula unmodified. Telopodite relatively short and robust, set
against coxa at nearly a right angle; prefemur with targe process, apically
expanded and partially enclosing acropodite; latter simple, with distinct trace of
cingulum on lateral side at about midlength, apically with small slender
solenomerite and tibiotarsal process of generally similar size and shape; no trace of
torsion. Prostatic groove visible for its entire length, running obliquely from its
base to ventral surface of prefemur, thence abruptly reflexed dorsad across
prefemur and proceeding to solenomerite along dorsemedian edge of acropodite
(Fig- 7).

22

Myriapodologica

Distribution: Southeastern Brasil, from vicinity of Rio de Janeiro to the
northeastern municipalties of Sao Paulo, at moderate to high elevations.

Referred species: Eight, listed below. Some of these may perhaps be shown to
be subspecifically related. Many additional species are to be expected.

Commentary: Sfrongy/osomides was really based primarily upon the reduced
state of the paranota in its type species, an adaptive character of somewhat
marginal taxonomic importance. Attems’ assignation of Lepfodesmus cylindricus
to the genus in 1938 was made for the same reason, and was only fortuitously
correct. In 1951 Schubart described a close relative of petropolites from Est. RJ,
Brasil, with the perceptive remark ‘The little black L. manfimus possesses
likewise short keels. As to the structure of the gonopods it forms withL. azeuedoi
and L. soaresi a well distinguished group, characterized by the curvature of the
sperm canal, the division between the femur and postfemur, and the peculiar form
of the prefemoral process.” Curiously Schubart overlooked the fact that
Brolemann’s good drawings of c\^lmdricus show the same configuration; had he
placed more emphasis on gonopods and less on superficial body-form characters
Schubart might have come thirty years ago to the very same conclusions
presented in this paper.

These are, in summary, that Sfrongy/osomidcs is a valid and easily recognized
taxon made up of small to very small, dark-colored millipeds having a similar body
form, sternal ornamentation, and basic gonopod pattern, all confined to a compact
and continuous geographic range generally between the cities of Rio de Janeiro
and Sao Paulo.

Since it is virtually impossible to verbalize subtle differences in gonopod
structure in an intelligible way, reference to drawings is required for the
identification of species. For this reason I forego attempting to prepare a
traditional dichotomic key. Following a chronologically structured list of species, I
append some comments on apparent species-groups, however.

Strongylosomides petropolites Attems. — Fig. 1.

Leptodesmus (Strongylosomides) pefropo/rfes Attems, 1901, Mitt. Mus.

Hamburg, vol. 13, p. 89, figs. 13-15, 36. Holotype (body apparently lost, only the

gonopods are now extant) Zool. Mus. Hamburg, from Petropolis, Mun.

Petropolis, Edo. Rio de Janeiro, Brasil, Dr. F. Ohaus leg.

Strongy/osomides pefropo/rtes: Attems, 1931, Zoologica, vol. 30, heft 79, p. 51, fig.

74; 1938, Das Tierreich, lief. 69, p. 98, fig. 114.

As remarked in a previous paragraph, Attems’ original drawings of the
gonopods of this species are entirely accurate but made from a dorsal aspect in

which a number of important details are not evident. Figure 1 shows the left
gonopod telopodite in mesal aspect and dearly presents characters shared with
the seven other referred species. From Attems’ noncommital description of leg
and sternum structure it may be presumed at least that tibial pads are probably not
present in this species.

Attems could not determine the length of the holot\/pe, but stated its width to be
2 mm. Judged from the proportions of related species, males of pet ropo/rtes must
be about 12 mm. long, a dimension which ranks the species among the smallest
known chelodesmids (Trichomorpha reducta Carl is only 19 mm. long and 1.2
mm. wide).

Hoffman: Strongylosomides

23

Strongylosomides virgulatus (Attems), comb, nov, — Figs. 2-8,

Lep^o(iesmus virgulatus Attems, 1901, Mitt. Naturh. Mus. Hamburg, vol. 13, p. 91,
figs. 19-21. Male lectotype and two lectoparatypes, Zoo!. Mus. Hamburg, from
Petropolis, Mun. Petropolis, Est. Rio de Janeiro, Brasil; Dr. F. Ohaus leg. 1898).
Leptodesmus (Leptodesmus) virgulatus: Attems, 1938, Das Tierreich, lief. 69,
p. 24 (description only; the gonopod shown in fig. 22 is that of Cornafafus
permutatus Attems, 1938, the result of some kind of transposition).

The accompanying figures are made from the lectotype to show details of
gonopod and peripheral structure. To be especially noted is the occurrence of
small, acute, apical prefemoral spines (Fig. 5), not previously remarked for this or
other species and therefore requiring future inspection.

Strongylosomides cylindricus (Brolemann)

Leptodesmus cytindricus Brolemann, 1902, Revista Mus. Paulista, vol. 5, p. 71,
figs. 50-55. Male holotype (?Mus. Zool. Univ. Sao Paulo), from Piquete, Mun.
Piquete, Est. Sao Paulo, Brasil; January 1897 [H. von Ihering, leg.?].
Sfrongy/osomides cy/indncus: Attems, 1938, Das Tierreich, lief. 69, p. 98, fig.
115,“Schubart, 1955, Arq. Mus. Nac., vol. 42, p. 510.

Brolemann’s detailed description and precise illustrations leave nothing to be
desired. His figures 52 and 53 show very clearly the apparent segmentation of the
gonopod acropodite on the lateral side. S. cy/indrfeus is one of the few members of
the genus with prominent apical tibia! pads and is also unusual in having the
peritremata and posterior edge of the metazona reddish.

Strongylosomides cognatus (Brolemann), comb. nov.

Leptodesmus cognatus Brolemann, 1902, Revista Mus. Paulista, vol. 5, p. 73, figs.
56 60. Male and female syntypes (Mus. Zool. Univ. Sao Paulo) from “Alto da
Serra” [=Paranapiacaba], Mun. Sto. Andre, Est. Sao Paulo, Brasil.
Camptomorpha cognata: Attems, 1938, Das Tierreich, lief. 69, p. 72, fig. 84.-“
Schubart, 1955, Arq. Mus. Nac., vol. 42, p. 511.

Camptomorphoides cognata: Schubart, 1962, Rev. Brasil. Biol., vol. 22, p. 254.

This species likewise appears to be known only from the original material. As in
cy/indrfeus the tibiae are provided with apical pads. The gonopods are very similar
to those of S. petropofites except for loss of the tibiotarsal process (a presumably
secondary reduction shared with S. uirgu/atus).

Strongylosomides azevedoi (Schubart), comb. nov.

Leptodesmus azevedoi Schubart, 1945, Pap. Avuls. Dept. Zool. S. Paulo, vol. 6,
p. 306, figs, 4, 5. Male holotype (Mus, Zool. Univ. Sao Paulo), from Monte
Alegre, Mun. Amparo, Edo. Sao Paulo, Brasil; O. Schubart leg. 1 November
1943.

24

Myriapodo/ogica

Strongylosomides maritimus (Schubart), comb, nov.

Lepfodesmus marifimus Schubart, 1951, Bol. Mus. Nac. (N.S.) no. 101, p. 7,
figs, 3, 4. Male holotype (Mus. Nac. Brasil.) from Ilha Grande, Edo. Rio de
Janeiro, Brasil, H. Sick leg. 14 June 1944.

Strongylosomides soaresi (Schubart), comb. nov.

Leptodesmus soaresi Schubart, 1946, An. Acad. Brasil. Cienc., vol. 18, p. 175,
fig. 6. Male holotype (Mus. Zool. Univ. Sao Paulo), from Fazenda Florcsta,
Ipiabos, Mun, Barra de Pirahy, Edo. Rio de Janeiro, Da. L. M. Morais leg. 11
September 1944.

In many respects this is a somewhat disjunct sp>ecies, whose status vis-a-vis
other members jof the genus is discussed in the following section. In the original
description Schubart remarked that “Esta especie merece talvez um subgenero,
por causa dos gonopodios estranhos do tipo normal. Existe alem do prefemur com
o processo prefemoral um femur nitidamente separado do postfemur.” This
observation is entirely accurately when sooresf is compared to the other eleven
species described in the same paper, but Schubart overlooked that the characters
he mentioned as “estranhos” occur also in S. cyfindrfcus, which following Attems
he himself admitted to Strongy/osomides.

Strongylosomides nuptae (Schubart), comb, nov,

Leptodesmus nuptae Schubart, 1955, Arq. Mus. Nac., vol. 42, p. 524, fig. 21. Male
holotype (Mus. Zool. Univ. Sao Paulo) from Veu das Noivas, Itatiaia, Mun.
Rezende, Est. Sao Paulo, Brasil; Da Jandira Schubart leg. 17 November 1945.

SPECIES GROUPS

On the basis of their overall appearance, the gonopods of the eight species
enumerated above suggest that four groups may be recognized, and to a large
extent these distinctions are confirmed by the occurrence of peripheral
characters.

All but one of the species are generally very similar in gonopod structure, as
exemplified by Figs. 1 and 7 of this paper. The exceptional form is S. soaresi, in
which the coxa is provided with only a rudimentary dorsal apophysis, the apical
elements of the acropodite are curved about 90° dorsad, and the separation of
femoral and postfemoral regions is emphasized by a proximad reflexion.
Moreover, this species is yellowish dorsally and the 6th sternum of the male lacks
paramedian processes. Collectively these differences set soaresi apart as the most
disjunct member of the genus, in its own monobasic group.

S. c^lindricus is unusual in that the prefemoral process of the gonopod is
appreciably shorter than the acropodite. Apical elements of the latter are also
directed dorsad at about a 45° angle. While cy/indricus is basically dark in dorsal
color, it differs from the other six sombre species in having the peritremata and
transverse metazonal bands reddish. While generally not so deviant as sooresf,
cylindricus may still merit assignment to its own group.

Hoffman: Strongj^^losomides

25

segment, dorsal aspect. 3, lateral aspect of same paranotum. 4, posterior
segments, dorsal aspect. 5, leg from midbody segment, showing small apicoventral
prefemoral spine. 6, coxa of right gonopod, dorsal aspect. 7, left gonopod, mesal
aspect. 8, left gonopod lateral aspect. Scale represents 2.0 mm for Figs. 2-5, 1.0
mm for Figs. 6-8. All drawings from holotype.

26

Myriapodologica

The remaining six species arc much more homogeneous, and appear to form a
third, equivalent group. Yet they can be segregated easily into two subgroups on
the basis of the prefemoral process, as seen in mesal aspect.

In the first of these the process tends to be relatively long, straight, and simple in
form, much as is shown in Figure 1. Species so distinguished arc petropolites,
azevedoi, and cognatus.

In the second, the prefemoral process is shorter, broader, more elaborate in
outline, and envelopes the acropodite to a greater extent, as shown by Figure 7.
One easily noted character is the common presence of a sharp retrorse subapical
projection on the dorsal side of the process. Included in this subgroup are the
species uirgu/atus, marittmus, and nuptae.

One member of each group fcognatus and uirgu/afus) differs somewhat in
lacking the usual tibiotarsal process. Weighing this character against the overall
appearance of the gonopods, I am inclined to consider it to be one reflecting
independent parallel reduction and of slight importance in indicating affinities.

Geographically the three members of the petropolites subgroup are located at
the extreme ends of the known generic range. The trio composing the uirgufotus
subgroup are more closely aggregated in the northeastern third of the area and are
close enough to suggest the possibility of their being found conspecific.

Since additional species doubtless remain to be discovered and documented in
this genus, the foregoing groupings must be regarded as provisional and subject to
dissolution or rearrangement.

REFERENCES

Attems, C. Graf von, 1901. Neue Polydesmiden des Hamburger Museums. Mitt.
Naturh. Mus. Hamburg, v. 18, pp, 85- 107, figs. 1-36.

— 1931. Die Familie Leptodesmidae und andere Polydesmiden. Zoologica
(Stuttgart) v. 30, heft 79, pp. 1-149, figs. 1-245.

— 1938. Fam. Leptodesmidae, Platyrhachidae, Oxydesmidae,
Gomphodesmidae, in Das Tierreich, lief. 69, pp. 1-487, figs. 1-509.

Brolemann, H. W., 1902. Myriapodes du Musee de Sao Paulo. Reyista Mus.
Paulista, vol. 5, pp. 35-237, figs. 1-271.

Schubart, Otto, 1945. Diplopodos de Monte Alegre (Municipio de Amparo, Est. de
Sao Paulo). Pap. Avuls, Dept. Zool. Sao Paulo, vol. 6, pp. 283-320,
figs. 1-15.

— 1946. Contribucao ao conhecimento do genero Leptodesmus (Fam. Lepto-
desmidae, Diplopoda). An. Acad. Brasil. Cienc., vol, 18, pp. 165-202. figs.
1 - 12 .

— 1951. Sobre alguns Leptodesmidae do Distrito Federal do Brasil e do
Estado do Rio de Janeiro. Bol. Mus. Nac. n. s., no. 101, pp. 1-15, figs. 1-18.

— 1955. Materials para uma fauna do Estado de Sao Paulo —
Leptodesmidae. Arq. Mus. Nac., vol. 42, pp. 507-540, figs. 1-30.

Address of the author: Department of Biology, Radford University, Radford,
Virginia 24142.

Manuscript review by Dr. Brent D, Opell, Department of Biology, Virginia
Polytechnic Institute & State University, Blacksburg, Vir^nia 24061.