Neosarmatium Serène & Soh, 1970

Ragionieri, Lapo, Fratini, Sara & Schubart, Christoph D., 2012, Revision Of The Neosarmatium Meinerti Species Complex (Decapoda: Brachyura: Sesarmidae), With Descriptions Of Three Pseudocryptic Indo-West Pacific Species, Raffles Bulletin of Zoology 60 (1), pp. 71-87 : 83-84

Key to species of Neosarmatium Serène & Soh, 1970

(modified from Davie, 1994; Schubart & Ng, 2002; Rahayu & Davie, 2006)

1. Lateral carapace margins more or less straight, without clear antero- and posterolateral separation .................................... 2

– Lateral carapace margins more or less sinuous, antero- and posterolateral margins relatively clearly demarcated ........... 3

2. Carapace rectangular, lateral margins weakly convergent posteriorly; anterolateral margin with distinct tooth behind exorbital angle; dorsal margin of cheliped dactylus with 4 evenly spaced tubercles; chelipeds subequal ............ N. leave

– Carapace trapezoidal, lateral margins strongly convergent posteriorly; anterolateral margin without tooth; dorsal margin of cheliped dactylus with 4 large submedian tubercles and row of numerous small granules along proximal margin; chelipeds distincly unequal ....................................................... N. tangi

3. Anterolateral margin entire, or if a low angular tooth behind exorbital angle then not separated by deep notch from rest of margin (exorbital breadth subequal to length of carapace; male unknown) ............................................................. N. integrum

– Side of carapace with 1 or 2 anterolateral teeth (second often reduced to angular projection) .............................................. 4

4. Dactylus of male cheliped with strong chitinous teeth on dorsal margin .................................................................................... 5

– Dactylus of male cheliped either without strong chitinous teeth on dorsal margin, or bearing small, sharp, chitinous spinules only ...................................................................................... 13

5. Dactylus of male cheliped with 2 teeth on dorsal margin ... 6

– Dactylus of male cheliped with 3–5 teeth on dorsal margin .. ................................................................................................ 9

6. Male chela with protruding basal shelf on outer face of fixed finger below gape; 1 dactylar tooth placed medially, other subproximally ........................................................ N. indicum

– Male chela without protruding basal shelf on outer face of fixed finger below gape .................................................................. 7

7. Inner surface of palm without strongly raised, granular, vertical crest (4 or 5 granules may be prominent on large males but are not raised onto a protruding crest); dorsal dactylar tubercles restricted to proximal quarter; distal-most tooth placed dorsal to large subproximal tooth on cutting margin; first tooth placed halfway towards base of dactylus .................... N. bidentatum

– Inner surface of palm with a strongly raised, granular, vertical crest; dactylar tubercles otherwise positioned ...................... 8

8. Distal tooth on upper surface of dactylus placed close to middle; upper surface of palm of cheliped with strong longitudinal rim marking outer edge; carapace 1.15–1.25 times longer than wide .............................................................. N. malabaricum

– Distal tooth on upper surface of dactylus placed clearly less than half-way to tip; longitudinal rim present on upper surface of palm of cheliped but not strongly differentiated; carapace 1.25–1.35 times longer than wide ..................... N. punctatum

9. Dactylus of male cheliped with 3 tubercles (one may be smaller, non-chitinous) on dorsal margin ......................................... 10

– Dactylus of male cheliped with 4 or 5 teeth on dorsal margin ......................................................................... N. rotundifrons

10. Carapace distinctly vaulted, more or less rectangular (1.2–1.28 times wider than long); carapace dorsal surface almost smooth, setae present as very short, small tufts, hardly discernible; somite 6 of male abdomen not markedly elongated (much wider at base than long) ............................................................................. 11

– Carapace squarish (less than 1.2 times wider than long); carapace dorsal surface with prominent tufts and rows of setae; somite 6 of male abdomen markedly elongated (length equal to width) .............................................................................................. 12

11. First anterolateral carapace tooth sharply angular, prominent, anteriorly directed, separated from exorbital angle by deep V-shaped notch; dorsal surface of dactylus typically with 3 chitinous teeth on proximal half .............................. N. daviei

– First anterolateral carapace tooth low, blunt, separated from exorbital angle by broad U-shaped sulcus; dorsal surface of dactylus bearing 3 teeth on proximal third, a pair of closelyset chitinous teeth, and 1 very small, proximal, non-chitinous tooth ..................................................................... N. papuense

12. Dactylar teeth truncate, spaced evenly over proximal half ..... ................................................................................... N. smithi

– Dactylar teeth acute, set close together over proximal twofifths ................................................................. N. trispinosum

13. Dactylus of cheliped smooth, unarmed (walking legs relatively slender, length of merus of third walking leg 2.6–2.7 times width; male first gonopod short, with distal portion not strongly narrowing, and strongly twisted) ........................................ 14

– Dactylus of cheliped armed with small, sharp, chitinous spinules (length of merus of third walking leg 1.9-2.1 times width; male first gonopod straight and distally curved inward with outer margins convex; apex of gonopod moderately fold towards medial plane of body ........................................................... 15

14. Inner angle of carpus of cheliped unarmed; inner face of palm with vertical row of granules behind gape ............. N. inerme

– Inner angle of carpus of cheliped armed with acute granular projection; inner face of palm with a patch of granules ventrally but not extending as a vertical row behind gape ..................... .......................................................................... N. spinicarpus

15. Male chela ca. 1.6 to 1.7 times longer than high; chelar dactylus spinules in a single row, vertical granular row on inside of chela relatively strong ................................................................... 16

– Male chela ca. 1.8 times longer than high; lower margin straight behind fixed finger; chelar dactylus spinules numerous, not confined to a single row; vertical granular row on inside of chela relatively low ........................................ N. fourmanoiri

16. Carapace borders gently concave in middle section without indication of second anterolateral tooth; chelar dactylus spinules evenly spaced in a single row, extending only to about two-thirds length of dactylus; a single vertical granular row on inside of chela strongly developed ..................................................... 17

– Carapace borders straight or convexly rounded with second anterolateral tooth weakly marked; chelar dactylus spinules in a single row, extending to the tip of dactylus .................... 18

17. Male abdomen with male abdominal somite 6 width 1.29 its length, telson length 1.15 times width ................. N. meinerti

– Male abdomen with male abdominal somite 6 width 1.35 times length, telson length 1.24 times width .............. N. africanum

18. Carapace border straight; male chela ca. 1.7 times longer than high; double row of weak granules on inside of chela; male abdomen with abdominal somite 6 width 1.13 times length, telson length 1.1 times width ............................. N. asiaticum

– Carapace border convexly rounded; male chela ca. 1.6 times longer than high; single row of weak granules on inside of chela; male abdomen with abdominal somite 6 width 1.14 times length, telson length 1.2 times width ............. N. australiense