Atlantodesmus Hoffman, 2000

Bouzan, Rodrigo Salvador, Pena-Barbosa, João Paulo P. & Brescovit, Antonio Domingos, 2017, Taxonomic review of the genus Atlantodesmus Hoffman, 2000 (Polydesmida: Chelodesmidae), Zootaxa 4236 (2), pp. 269-290: 271

publication ID

https://doi.org/10.11646/zootaxa.4236.2.3

publication LSID

lsid:zoobank.org:pub:8A62CD73-AE84-47D1-8E31-9FD256086BF1

persistent identifier

http://treatment.plazi.org/id/2B5A8354-FF8B-EB26-FF57-6B8626C8F81D

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scientific name

Atlantodesmus Hoffman, 2000
status

 

Genus Atlantodesmus Hoffman, 2000 

Atlantodesmus Hoffman, 2000: 101  –113. Type species: A. eimeri ( Attems, 1898)  , by original designation. Iemanja Hoffman, 2000: 101  –113. Type species: I. teresa Hoffman, 2000  . New synonymy.

Justification of synonymy: Hoffman (2000) described two genera, similar in body features and gonopod structures: Atlantodesmus  and Iemanja  . Despite the similarities, Hoffman (2000) distinguished both genera through two features: presence of a cingulum and folds in the posterior margin of the gonopod opening in Iemanja  (see Hoffman, 2000, figs 2, 14).

Our examination of specimens of the genus Atlantodesmus  revealed that all species have folds at the posterior edge of the gonopod aperture, as well as a discontinuity in the transition zone between the prefemoral region and the acropodite region, indicating the presence of a cingulum in ectal view in all species. Hence, there is no reason to separate the species into two distinct genera.

Diagnosis. Males of Atlantodesmus  differ from other chelodesmid genera by the combination of the following characters: transition zone of the pre-femoral region to the acropodal region with a cingulum ( Fig. 7View FIGURE 7 C, 10C); acropodite branching proximally, forming long, thin falciform solenomere and a large acropodite process with a broadened apical region and overreaching the tip of the solenomere.

Description. Body length between 40 mm ( A. itapurensis  ) and 74 mm ( A. teresa  ). Coloration (specimens preserved in alcohol) variable among species, ranging from black to light brown. Head: face with three rows of bristles ( Fig. 1View FIGURE 1 A), shape of the Tömösváry organ suboval ( Fig. 1View FIGURE 1 B). Antenna: distal antennomere with invaginations between the four apical sense cones and spiniform basiconic sensilla ( Figs 1View FIGURE 1 C–E). Body rings: integument with small tubercles on the metazonite ( A. eimeri  ), rough in A. pintoi  and A. teresa  , and smooth in A. itapurensis  and A. pickeli  , all of them without bristles. Collum: anterior border arched and posterior border ranging from straight to slightly curved ( Figs 2View FIGURE 2 A–B). Segments with lateral projections ( Figs 8View FIGURE 8 B, 11B, 15A, 18B) dorsal to the stigma. Stigma oval ( Fig. 2View FIGURE 2 E). Sternite of fourth segment with two ventral projections in A. itapurensis  and A. teresa  ( Figs 11View FIGURE 11 A; 18A). Ozopore situated on the posterior edge of paranota. Ozopore arrangement: 5, 7, 9, 10, 12, 13, 15–19; ozopores surrounded by peritremata ( Figs 2View FIGURE 2 C–D). Paranota: prominent and long, wide and nearly horizontal, slightly elevated on sides, covering part of the legs, without bristles on the edges. Paranota form: anterior corners rounded, posterior edges acutely produced ( Fig. 2View FIGURE 2 C). Legs: without modifications, with thin and slightly elongated bristles ( Fig. 1View FIGURE 1 F). Telson: triangular ( Fig. 2View FIGURE 2 F), with five pairs of macrobristles on the dorsal side and two pairs in the apical region.

Male characters: Gonopore: located on the coxae of the legs of the third segment, coxae rectangular, with an apical pore ( Fig. 3View FIGURE 3 C). Gonopod aperture on seventh body ring: transversely oval, large; posterior edge with folds ( Figs 7View FIGURE 7 E–F). Central support of gonopods are sclerotized ( Fig. 7View FIGURE 7 E, arrow). Gonopods: Gonopod coxae width ( Fig. 3View FIGURE 3 A): equivalent to about half the length of the telopodite, often with spiniform process ( Fig. 3View FIGURE 3 B); coxae prominent in ectal view. Cannula ( Fig. 3View FIGURE 3 A): hook-shaped. Spermatic (prostatic) groove ( Fig. 3View FIGURE 3 A): runs along mesal side of the acropodite, does not change trajectory at the cingulum. Telopodite ( Fig. 3View FIGURE 3 A): elongated and inclined, divided into two parts: the prefemoral region ( Fig. 3View FIGURE 3 A) and the femoral region ( Fig. 3View FIGURE 3 A). Prefemoral process ( Fig. 3View FIGURE 3 A): long branch without projections, reaching almost tip of solenomere. Cingulum: delimiting the prefemoral region and femoral region ( Fig 3View FIGURE 3 B); conspicuous in A. itapurensis  and A. teresa  , and reduced in A. eimeri  , A. pickeli  and A. pintoi  . Cingulum difficult to observe even using a stereomicroscope in A. eimeri  and A. pintoi  . Solenomere ( Fig. 3View FIGURE 3 A): elongated and sickle-shaped, rising proximally from the femoral region; shielded by large and broad acropodite process ( Fig. 3View FIGURE 3 A); acropodite process shape species-specific. Female characters: Cyphopods: ovalshaped, situated directly behind the second pair of legs on the third segment; composed of three valves, all of them with bristles; two valves joined by a membrane, with a third apically, appressed against both larger valves ( Fig. 3View FIGURE 3 D).

Distribution. Known from the states of Bahia to Santa Catarina, occurring in the Atlantic rain forest and in the Cerrado area of Brazil ( Fig. 19View FIGURE 19).

Composition. Five species, Atlantodesmus eimeri ( Attems, 1898)  , A. itapurensis ( Schubart, 1943)  , A. pickeli ( Schubart, 1946)  , A. pintoi ( Schubart, 1946)  , A. teresa ( Hoffman, 2000)  , new combination.

Kingdom

Animalia

Phylum

Arthropoda

Class

Diplopoda

Order

Polydesmida

Family

Chelodesmidae

Loc

Atlantodesmus Hoffman, 2000

Bouzan, Rodrigo Salvador, Pena-Barbosa, João Paulo P. & Brescovit, Antonio Domingos 2017

2017
Loc

Atlantodesmus

Hoffman 2000: 101Hoffman 2000: 101