Belongs within: Eugnatha.
The Spirostreptidae are a family of often large millipedes. The lateral ends of the collum bear several parallel striations, and the lingual lamellae are not separated by any projection of the mentum or promentum (Hoffman 1990).
Characters (Hoffman 1990): Stipes of gnathochilarium widely separated by large central mentum, but lingual lamellae in contact, not separated by mentum or promentum; lateral ends of collum with several parallel engraved striations; sterna, pleura and terga coalesced into rigid cylindrical rings, with pleural sclerites completely coalesced with lower ends of terga, no suture line remaining; segment 3 without legs.
<==Spirostreptidae [Spirostreptidea]
| i. s.: Charactopygus frequensH02
| OrthoporusL62
| |--O. cobanusL62
| |--O. flaviorC90
| |--O. kiemi Loomis 1962L62
| |--O. luchicolensL62
| |--O. ornatusC90
| `--O. paxillicauda Loomis 1962L62
`--SpirostreptinaeK55
|--Spirostreptus ibandaH02
|--EpistreptusK55
| |--E. (Epistreptus)K55
| | |--*E. (E.) oscenus Silvestri 1897K55
| | `--E. (E.) silvestrii Kraus 1955K55
| `--E. (Microtrullius) vagans (Chamberlin 1922) (see below for synonymy)K54
`--Scaphiostreptus [incl. Andineptus Chamberlin 1941]K55
| i. s.: S. rugicepsK54
`--S. (Scaphiostreptus)K55
|--S. (S.) absconsus (Chamberlin 1922) [=Orthoporus absconsus]K54
|--S. (S.) apheles (Chamberlin 1941) [=Andineptus apheles]K55
|--S. (S.) broelemanni (Verhoeff 1941)K55
|--S. (S.) delectus (Chamberlin 1941) [=Andineptus delectus]K55
|--S. (S.) huallagae Kraus 1955K55
|--S. (S.) perditus (Chamberlin 1941) [=Andineptus perditus]K55
|--S. (S.) pongus (Chamberlin 1941) [=Andineptus pongus]K55
`--S. (S.) salvadoricus Kraus 1954K54
Epistreptus (Microtrullius) vagans (Chamberlin 1922) [=Gymnostreptus vagans; incl. G. pacificus Chamberlin 1922, Epistreptus (Microtrullius) pacificus]K54
*Type species of generic name indicated
References
[C90] Crawford, C. S. 1990. Scorpiones, Solifugae, and associated desert taxa. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 421–475. John Wiley & Sones: New York.
Hoffman, R. L. 1990. Diplopoda. In: Dindal, D. L. (ed.) Soil Biology Guide pp. 835–860. John Wiley & Sones: New York.
[H02] Hunt, D. J. 2002. The African Rhigonematoidea (Nematoda: Rhigonematida). 1. Trachyglossus quintus gen. n., sp. n. (Xustrostomatidae fam. n.) with redescription of Rhigonema multipapillatum (Skrjabin, 1916) and designation of a neotype. Nematology 4: 671–686.
[K54] Kraus, O. 1954. Myriapoden aus El Salvador. Senckenbergiana Biologica 35 (5–6): 293–349.
[K55] Kraus, O. 1955. Myriapoden aus Peru, III. Senckenbergiana Biologica 36 (3–4): 173–200.
[L62] Loomis, H. F. 1962. Two unusual Central American spirostreptid milliped species. Proceedings of the Biological Society of Washington 75: 47–52.