Pachybolidae

Pachybolidae, Cook, 1897, is a diverse millipede family with around 69 genera totaling upwards of 312 different species spread across 4 subfamilies: 

1. Centrobolinae Hoffman, 1980, 

2. Pachybolinae Cook, 1897, 

3. Spiromiminae Brölemann, 1913, 

4. Trigoniulinae Attems, 1909.

Pachybolidae has a worldwide distribution, with concentrations in India, Myanmar, Thailand, Laos, Cambodia, Malaysia, Philippines, and Indonesia. The family is also found in West Africa, South Africa, and Madagascar, the United States, the Caribbean, and the northern half of South America (Pachybolidae in GBIF Secretariat, 2021). 

The diagnostic features for Pachybolidae are posterior gonopods connected by a sclerotized sternite, and the absence of long, slender apodemes on the telopodite and coxite of the anterior gonopod. The sternal apodemes are absent or very small, while the tracheal apodemes of the posterior gonopods are large, sometimes just as large as the posterior gonopods themselves. 

References: 

1. Purkart, A. (2021). Epibolus pulchripes. Pachybolidae Family Page. Photograph. Permission granted solely to TMED. 

2. Cook, O. F. (1897). New relatives of Spirobolus giganteus. Brandtia (A series of occasional papers an Diplopoda and other Arthropoda), 18: 73-75

3. Sierwald, P.; Spelda, J. (2021). MilliBase. Pachybolidae Cook, 1897. Accessed at: http://www.millibase.org/aphia.php?p=taxdetails&id=888755 on 2022-01-22

4. Sierwald, P.; Spelda, J. (2021). MilliBase. Centrobolinae Hoffman, 1980. Accessed at: http://millibase.org/aphia.php?p=taxdetails&id=888832 on 2022-01-22

5. Sierwald, P.; Spelda, J. (2021). MilliBase. Pachybolinae Cook, 1897. Accessed at: http://www.millibase.org/aphia.php?p=taxdetails&id=888875 on 2022-01-22

6. Sierwald, P.; Spelda, J. (2021). MilliBase. Spiromiminae Brölemann, 1913. Accessed at: http://www.millibase.org/aphia.php?p=taxdetails&id=888890 on 2022-01-22

7. Brölemann, H. W. (1913). Un nouveau système de Spirobolides [Myriapoda. Diplopoda]. Bulletin de la Société entomologique de France. 1913(19): 476-478. Paris., available online at http://biodiversitylibrary.org/page/9201316

8. Hoffman, R. L. (1980). Classification of the Diplopoda. 1-237. Genève.

9. Pachybolidae in GBIF Secretariat (2021). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2022-01-23.