Trichodactylidae

The red freshwater crab Dilocarcinus pagei, from here.

Belongs within: Heterotremata.

The Trichodactylidae are a family of crabs found in rivers and lakes of South America, with some species in Mexico and Nicaragua.

Characters (from Rodríguez 1992): Penis lodged in penial groove located across middle of 8th sternite. First male gonopod conical or flask-shaped, with distal portion armed with strong conical spines; gonopore large V-shaped, open caudally, or narrow, slit-like, open distally and flanked by one or two corneous lamellae. Second male gonopod of equal length or much longer than first gonopod, exceptionally reduced to short flagellum. Efferent openings large, restricted below only by endopod of first maxilliped. Endopod of first maxilliped with inner ('portunoid') lobe. Exopod of third maxilliped, including flagellum, always well developed. Antennae usually with basal article expanded into outer lobe which, together with occlusive tooth, closes orbit near yugal angle. Podomeres of walking legs flattened, without spines, with rows of long hairs on upper and lower margins of propodus and dactylus, propodus of fifth pair widened. Carapace subcircular or subhexagonal, moderately wider than long (cb/cl = 1.05-1.25) with 1-12 relatively large lateral teeth; cervical grooves absent.

<==Trichodactylidae
    |  i. s.: Trichodactylus Latreille 1828 H86
    |           |--T. bidens Bott 1969 H86
    |           |--T. mensabak Cottarelli & Argano 1977 H86
    |           `--T. quinquedentatus Rathbun 1893 MT08a
    |         Sylviocarcinus devillei MT08b
    |--Valdiviini MT08b
    |    |--Valdivia gila [incl. V. cururuensis] MT08b
    |    `--Rotundovaldivia Pretzmann 1968 MT08b
    |         `--R. latidens (Milne-Edwards 1869) (see below for synonymy) MT08b
    `--Dilocarcinini MT08b
         |--Moreirocarcinus Magalhães & Türkay 1996 MT08a
         |--Goyazana Bott 1969 MT08a
         |    `--G. castelnaui (Milne Edwards 1853) [=Dilocarcinus castelnaui] MT08a
         |--Poppiana Bott 1969 MT08a
         |    |--*P. dentata (Randall 1840) (see below for synonymy) MT08a
         |    |--P. argentiniana (Rathbun 1905) (see below for synonymy) MT08a
         |    `--P. bulbifer (Rodriguez 1992) [=Dilocarcinus bulbifer] MT08a
         |--Bottiella Magalhães & Türkay 1996 MT08a, MT08b
         |    |--*B. medemi (Smalley & Rodríguez 1972) [=Dilocarcinus (Dilocarcinus) medemi] MT08b
         |    |--B. cucutensis (Pretzmann 1968) [=Valdivia (Rotundovaldivia) niceforei cucutensis] MT08b
         |    `--B. niceforei (Schmitt & Pretzmann 1968) (see below for synonymy) MT08b
         `--Dilocarcinus Milne Edwards 1853 MT08a
              |--D. septemdentatus (Herbst 1783) (see below for synonymy) MT08a
              |--D. laevifrons DC06
              |--D. pagei Stimpson 1861 (see below for synonymy) MT08a
              `--D. truncatus Rodríguez 1992 MT08a

Bottiella niceforei (Schmitt & Pretzmann 1968) [=Trichodactylus (Valdivia) niceforei, Dilocarcinus (Dilocarcinus) niceforei, Valdivia (Rotundovaldivia) niceforei, V. (R.) niceforoi (l. c.)] MT08b

Dilocarcinus pagei Stimpson 1861 [=D. page (l. c.); incl. D. (Dilocarcinus) pagei cristatus Bott 1969, D. (D.) pagei enriquei Pretzmann 1978, D. p. enricei (l. c.)] MT08a

Dilocarcinus septemdentatus (Herbst 1783) [=Cancer septemdentatus; incl. *D. spinifer Milne Edwards 1853, D. castelnaui guayanensis Pretzmann 1968] MT08a

Poppiana argentiniana (Rathbun 1905) [=Trichodactylus (Dilocarcinus) argentinianus, Dilocarcinus (Poppiana) argentinianus; incl. D. argentinianus apaluensis Pretzmann 1968, Trichodactylus (Dilocarcinus) bachmayeri Pretzmann 1968, Poppiana bachmayeri, T. (Valdivia) boliviensis Parisi 1923] MT08a

*Poppiana dentata (Randall 1840) [=Orthostoma dentata, Dilocarcinus dentatus, Trichodactylus (Dilocarcinus) dentatus; incl. D. dentatus cayennensis Pretzmann 1968, D. multidentatus von Martens 1869, D. dentatus trinidadensis Pretzmann 1968] MT08a

Rotundovaldivia latidens (Milne-Edwards 1869) [=Sylviocarcinus latidens, Valdivia (Rotundovaldivia) latidens, V. (Valdivia) serrata latidens; incl. Trichodactylus (V.) bourgeti Rathbun 1905, V. (Rotundovaldivia) bourgueti (l. c.), T. (V.) bourgueti (l. c.) falcipenis Pretzmann 1968, Rotundovaldivia falcipenis] MT08b

*Type species of generic name indicated

REFERENCES

[DC06] Daniels, S. R., N. Cumberlidge, M. Pérez-Losada, S. A. E. Marijnissen & K. A. Crandall. 2006. Evolution of Afrotropical freshwater crab lineages obscured by morphological convergence. Molecular Phylogenetics and Evolution 40 (1): 227-235.

[H86] Holthuis, L. B. 1986. Decapoda. In Stygofauna Mundi: A Faunistic, Distributional, and Ecological Synthesis of the World Fauna inhabiting Subterranean Waters (including the Marine Interstitial) (L. Botosaneanu, ed.) pp. 589-615. E. J. Brill / Dr. W. Backhuys: Leiden.

[MT08a] Magalhães, C., & M. Türkay. 2008a. Taxonomy of the Neotropical freshwater crab family Trichodactylidae, IV. The genera Dilocarcinus and Poppiana (Crustacea, Decapoda, Trichodactylidae). Senckenbergiana Biologica 88 (2): 185-215.

[MT08b] Magalhães, C., & M. Türkay. 2008b. Taxonomy of the Neotropical freshwater crab family Trichodactylidae, V. The genera Bottiella and Rotundovaldivia (Crustacea, Decapoda, Trichodactylidae). Senckenbergiana Biologica 88 (2): 217-230.

Rodríguez, G. 1992. The Freshwater Crabs of America: family Trichodactylidae and supplement to the family Pseudothelphusidae. IRD Editions.