Heterometrus Differentiation

[Terrena Laxamentum]

Is there a way to differentiate between Heterometrus longimanus and laevigatus? Is it by the pattern of granulation on the carapace?

 

[The Snark]

My method - so far - still learning. Red or deep almost black reddish telson, Longimanus. Always black telson, Laevigatus. They must be mature to go by color. This applies only to telling these two species apart.

@Joey Spijkers Some help here?

 

[Outpost31Survivor]

Is there a way to differentiate between Heterometrus longimanus and laevigatus? Is it by the pattern of granulation on the carapace?

Okay I will bite:

The 2020 revision made two corrections, H. cimrmani (Kovařík, 2004) is a junior synonym of H. laevigatus, the same is true for H. minotaurus, hence Heterometrus minotaurus (Plíšková et al., 2016) = Heterometrus laevigatus (Thorell, 1876), syn. nov


H. laevigatus:
Malaysia (Langkawi)
Myanmar
Thailand

H. longimanus:
Brunei
Andaman Islands
Indonesia
Malaysia (mainland, Borneo, Tinggi)
Philippines
Singapore

2020 taxonomic key:

1)

Carapace rostrolateral margin distinctly incised adjacent to posterior lateral ocelli; median ocelli relatively large, distance between them less than an ocellus width (fig. 23B, C); pedipalp patella proventral carina with prominent spiniform granule (fig. 186); pedipalp chela manus dorsal surface (adult ) depression proximal to fixed finger present and distinct (fig. 187B); legs I and II tibiae, pro- and retrolateral surfaces with scattered, setiform macrosetae, not arranged in definite row; legs I–IV telotarsi, pseudonychium (dactyl) prominent and acuminate (fig. 50E–H)......................... ..........2 (Heterometrus Ehrenberg, 1828)

2)

longimanus: Telson dark reddish brown, paler than metasomal segment V........................3

laevigatus: Telson blackish, as dark as metasomal segment V..................................5

3)

longimanus: Pedipalp () long, FLCW ≥ 0.80 and FL:CL ≥ 0.76 (figs. 159, 174); chela movable finger, second (subproximal) lobe () similar to or barely larger than other lobes on movable finger (figs. 162A, 177B, D); leg II basitarsus proventral surface, macroseta st usually spiniform (fig. 52B, F) . . . . . . . . . . . . . 4

5)

laevigatus: Pedipalp () long, FLCW ≥ 0.80 and FL:CL ≥ 0.76 (figs. 164, 189A, B); legs I and II basitarsi proventral surfaces, macroseta st spiniform (figs. 50A, B, 53A, B). . . . . . . . . . 6

4)

longimanus: Carapace interocular surface () granular along median longitudinal and anterior bifurcated sulci only (fig. 22C); posterolateral surfaces () smooth or nearly so (fig. 22D); pedipalp chela manus dorsal surface smooth or nearly so (fig. 177A, B); leg III basitarsus retroventral surface, macroseta sb setiform (fig. 52G). . . . . . . . . . . . . . . . . . . . . . ... Heterometrus longimanus (Herbst, 1800)

6)

laevigatus: Carapace interocular surface entirely smooth () (fig. 23A) or granular along median longitudinal and anterior bifurcated sulci only () (fig. 23B); pedipalp chela manus promedian carina () absent or obsolete; chela movable finger, second (subproximal) lobe () more strongly developed than other lobes on movable finger, with correspondingly well-developed notch in fixed finger (figs.
167B, 168B)....................................... Heterometrus laevigatus

 

[Terrena Laxamentum]

This does help me quite a bit, I'm going to check my pair when I get home later today. Maybe I'll get decent shots of their carapace and post them.

 

[Outpost31Survivor]

This does help me quite a bit, I'm going to check my pair when I get home later today. Maybe I'll get decent shots of their carapace and post them.

They both have sexual dimorphism taxonomic characteristics shared and different.