Heterometrus species with and without pronounced internal tubercle on patella

[Outpost31Survivor]

Six new Heterometrus species may have been discovered:

Heterometrus atrascorpius 2012 - India
Heterometrus liangi 2007**** - Vietnam
Heterometrus minotaurus 2016 - Thailand
Heterometrus telaganaensis 2010 - India
Heterometrus tibetanus 2005 - Tibet
Heterometrus yaleenis 2019 - Sri Lanka

**** As of 2017, species requires a confirmation of its validity. I can't wait for Prendini's update on the Heterometrus genus.

 

[Outpost31Survivor]

Yep I fudged some things in this thread and had to edit a couple of my posts. But its intent is to provide some references to AFS hobbyist anyways.

Heterometrus minotaurus (Thailand)

Differential diagnosis. The described features distinguish H. minotaurus sp. nov. from all other species of the genus. H. minotaurus sp. nov. from Thailand seems to be closest to H. longimanus (Herbst, 1800) from Indonesia (Java, Kalimantan and Sumatra), Singapore, Malaysia (Kalimantan) and Philippines. In published keys to the Heterometrus, the two species are categorized under the H. longimanus (Kovařík, 2009: 47–48, couplet 28). Males of the two species can be unequivocally separated by: 1) total length 90–140 mm in H. longimanus and 83 mm in H. minotaurus sp. nov.; 2) longer and more narrow metasoma in H. longimanus (ratio length to width the first metasomal segment is 0.96–1.04 in H. longimanus and 0.78 in H. minotaurus sp. nov.); 3) more densely granulated carinae on metasoma in H. longimanus (dorsalolateral carinae of the fourth metasomal segment consists of 12 or more granules in H. longimanus and 9 or less granules in H. minotaurus sp. nov.).

Male with fingers, chela, femur and patella of pedipalp narrow and long, ratio chela length manus width 3.42 in male. Chela not lobiform in male, smooth, sparsely tuberculate with pronounced partly incomplete carination. Patella smooth with seven obsolete carinae developed, with pronounced internal tubercle. Femur smooth, with four granulate carinae developed. Fingers long (ratio chela length movable finger length 1.78 in holotype male, curved and with straight rows of granules and internal and external denticles (Fig. 14).

 

[Outpost31Survivor]

Heterometrus liangi (Vietnam)

Diagnosis: Body length 82.20-98.00. This species is similar to H. laoticus in the shape of pedipalp chela, but the dorsal surfaces of carapace and mesosoma are granular (Fig. 1), they are smooth in H. laoticus; median-ocular carinae covered with granules (Fig. 1), median-ocular carinae smooth in H. laoticus; dorsointernal aspect of pedipalp chela manus with pointed granules (Figs. 15,23 ), it is smooth in H. laoticus; length to width ratio of chela 2.10-2.14 in males, 2.00-2.10 in females ( Table 1 ), the ratio is 2.00-2.30 in both sexes in H. laoticus. H. liangi sp. nov. differs from H. petersii in that the difference of chela movable finger is not noticeable in either sex (Figs. 14,15,22,23 ); chela movable finger of male exhibits a strong knob near the middle in the latter. Description (based on male holotype and one female paratype): Measurements in Table 1. Coloration: Body basically black to reddish black. Prosoma: carapace black to reddish black, posterior median and posterior lateral furrows yellowish brown. Mesosoma: black, tergites I-VI each with a pair of paler spots near center of anterior margins and with black spaces between the spots. Sternites blackish, sternites III-VI reddish brown in the middle of posterior half. Genital operculum yellowish brown and pectines yellowish. Metasoma: all segments blackish, carinae black. Telson: blackish to reddish brown on the dorsum, aculeus reddish brown at the base and blackish brown at the extremity. Pedipalp: femur and patella blackish brown, chela manus reddish brown with indistinctly reticulate stripes, but fingers blackish brown.

http://en.cnki.com.cn/Article_en/CJFDTotal-ZXXB200702007.htm

Basically it is granular where H.laoticus is smooth but lacks the sexual dimorphism of H.petersii.

 

[Outpost31Survivor]

H.petersii and H.laoticus closely resemble each and can be mistakenly identified for each other. Outside of the obviously male sexual dimorphism on the moveable chela finger (H.petersii), they are distinguishable.

Pic #1 H.laoticus is completely devoid of granulation on both the carapace and tergites.

Pic #2 H.petersii is granulated on both the carapace and tergites.

I know this is old news for most but there are frequent newcomers asking for their AFS to be IDed which I guesstimate 100% are H.petersii.

 

[Outpost31Survivor]

According to Collin Clary, Lorenzo Prendini's new revision of the Heterometrus genus should be out early 2020. I can't wait to get my paws on it.

The pic is not a preview of the Prendini revision just a cool pic.

 

[Outpost31Survivor]

Female H.longimanus and female H.spinifer can be very very difficult to tell apart. They can easily be misidentified.

Pic #1: The manus of H.longimanus is sparcely tuberculate but the manus of H.spinifer is smooth and punctate.

Pics #2-3: The manus of the chela in H.spinifer with carinae forming irregular reticulations.

 

[Outpost31Survivor]

This thread is to provide guidelines between common south-east Asian Heterometrus species. Such as the pronounced internal tubercle of the patella only occurs in several species of AFS. And that several species are sexually dimorphic. Breeder Dylan Keife opened my eyes to some details on H.cyaneus.

H.cyaneus is described as having a greenish-black (or bluish-black) sheen when placed directly under a light.

PICS #1&2: H.cyaneus is granulated all over, the carapace approaching the median eyes, the femur, patella, and manus. The telson may be reddish-brown. Patella of pedipalp without pronounced internal tubercle. No noticeable sexual dimorphism.

I hope Prendini will be alot more detailed than Kovarik was and more reliable than Couzjin was. But I am sure we will gain greater insights on the newly described species and less common species.

 

[Outpost31Survivor]

H.cyaneus (non-highlight pics):

 

[Outpost31Survivor]

H.petersii and H.laoticus closely resemble each and can be mistakenly identified for each other. Outside of the obviously male sexual dimorphism on the moveable chela finger (H.petersii), they are distinguishable.

Pic #1 H.laoticus is completely devoid of granulation on both the carapace and tergites.

Pic #2 H.petersii is granulated on both the carapace and tergites.

I know this is old news for most but there are frequent newcomers asking for their AFS to be IDed which I guesstimate 100% are H.petersii.

Dorsal pic of H.petersii with granule locations on carapace and mesasomal tergites highlighted in purple. H.laoticus is completely devoid of these. The latter has a clean slate.

A couple of distribution corrections:

H.bengalensis - India, West Bengal
H.latimanus - India, Pakistan

There could be more I am unaware of.

 

[Outpost31Survivor]

sorry post deletion.