Parastacus, Huxley, 1879

Huber, Augusto Frederico, Araujo, Paula Beatriz & Ribeiro, Felipe Bezerra, 2022, The hole is deeper: description of two new species within the Parastacus brasiliensis (von Martens, 1869) species complex with an integrative taxonomy approach, Zootaxa 5168 (3), pp. 251-284 : 275-276

Uptaded key to Parastacus

The following key is modified from proposed in Rogers et al. (2020) with the addition of Parastacus macanudo , P. gomesae sp. nov. and P. guapo sp. nov.. The modifications of the original key and new steps start in step number eight (8) and these were elaborated according to information from Ribeiro et al. (2016; 2017; 2020) and Huber et al. (2018; 2020).

1 Telson with lateral spines............................................................................... 2

1’ Telson without lateral spines, maxilliped III exopod flagellum surpassing ischium distal margin............................................................................................... Parastacus nicoleti ( Philippi, 1882)

2(1) Postorbital carina proximal edge ending in a strong spine; uropod protopod proximal lobe bearing a spine; areola delimited by carinae.............................................................................................. 3

2’ Postorbital carina proximal edge not ending in spine; uropod protopod lobe lacking spine; areola not delimited by carinae.. 4

3(2) Cheliped merus, carpus, and propodus medially with tufts of long setae; maxilliped III ischium ventral margin with longitudinal spine row................................................................ Parastacus varicosus Faxon, 1898

3’ Cheliped merus, carpus, and propodus medially glabrous; maxilliped III ischium ventral margin with longitudinal tubercle row...................................................................... Parastacus saffordi Faxon, 1898

4(2’) Telson distal margin rounded........................................................................... 5

4’ Telson distal margin acute.................................... Parastacus buckupi Huber, Ribeiro & Araujo, 2018

5(4) Cheliped carpus distally glabrous; epistome anteromedian lobe hexagonal or pentagonal............................ 6

5’ Cheliped carpus distally with tufts of long and simples setae; epistome anteromedial lobe heptagonal........................................................................... Parastacus pilicarpus Huber, Ribeiro & Araujo, 2018

6(5) Cheliped dactyl and pollex cutting edges obscured by long setal tufts............................................ 7

6’ Cheliped dactyl and pollex cutting edges visible............................................................. 8

7(6) Postorbital carinae prominent.......................................... Parastacus pilimanus ( von Martens, 1869)

7’ Postorbital carinae obsolete....................................... Parastacus laevigatus Buckup and Rossi, 1980

8(6) Chelipeds with globose palm............................................................................ 9

8’ Chelipeds with flattened palm.......................................................................... 11

9(8) Cervical groove U-shaped.................... Parastacus caeruleodactylus Ribeiro and Araujo in Ribeiro et al., 2016

9’ Cervical groove V-shaped.............................................................................. 10

10(9’) Rostral carinae reaching postorbital carinae proximal edge.......................... Parastacus defossus Faxon, 1898

10’ Rostral carinae surpassing postorbital carinae proximal edge...................... Parastacus pugnax (Poeppig, 1835)

11(8’) Telson subrectangular................................................................................ 12

11’ Telson subtriangular.............................. Parastacus fluviatilis Ribeiro and Buckup in Ribeiro et al., 2016

12(11) Cheliped palm dorsal surface with tubercles irregularly distributed or with irregular tubercle rows.................... 13

12’ Cheliped palm dorsal surface with three well-defined tubercle rows....................................................................................... Parastacus tuerkayi Ribeiro, Huber and Araujo in Ribeiro et al., 2017

13(12) Cheliped ventral surface bearing one row of squamose tubercles............................................... 16

13’ Cheliped ventral surface bearing two rows of squamose tubercles.............................................. 14

14(13’) Telson lateral margins with large spines................................................................... 15

14’ Telson lateral margins with small spines............................................ Parastacus gomesae sp. nov.

15(14) Cephalon postorbital carinae prominent in anterior and middle portions..................... Parastacus guapo sp. nov.

15’ Cephalon postorbital carinae weakly prominent....... Parastacus macanudo Huber, Rockhill, Araujo and Ribeiro, 2020

16(13) Cheliped palm medial margin with medial area tuberculate, groove U-shaped.................................................................................................. Parastacus promatensis Fontoura & Conter, 2008

16’ Cheliped palm medial margin smooth; groove weakly V-shaped............ Parastacus brasiliensis ( von Martens, 1869)