New cases of anatomical malformations in scorpions

  

There have been quite a few articles documenting anatomical malformations in scorpions (teratology). In a recent article, Danniella Sherwood and co-workers document three more cases of anatomical malformations in a Lychas C.L. Koch, 1845 species from Australia and Parabuthus raudus (Simon, 1888) from Botswana (both Buthidae).

Abstract:
Three cases of tergite malformation are described: two in Parabuthus raudus (Simon, 1888) from Botswana and one in Lychas sp. from Australia. One adult female P. raudus had tergite IV almost split into two parts, an anomaly that also affected tergites II–III. In another female P. raudus, a longitudinal depression presented across tergites I–IV. In Lychas sp., tergites I–II are strongly constricted transversely, exposing the adjacent pleural membrane dorsally.

Reference:
Sherwood D, Jessnitz V, Tang V. Three more cases of tergite malformation in two buthid scorpion species revealed from citizen science data (Scorpiones: Buthidae). Revista Iberica de Arachnologia. 2025(46):135–7. [Full text available by authors]

Thanks to Danniella for sending me their article!

Another discovery of a scorpion with a double stinger

 

Malformations in scorpions are well-known, but in a recent research note Salah Eddine Sadine presents one of the more special malformations: The presence of a a double aculeus. This was seen in a female Androctonus amoreuxi (Audouin, 1826) (Buthidae) from Algeria. The female was normal except for the double stinger and this special malformation is probably not a handicap for the scorpion.

Abstract:
An adult female of the buthid scorpion Androctonus amoreuxi (Audouin, 1826) from a palm grove of Ghardaïa region (central Algeria) having a bifid aculeus (double aculeus) is recorded. This type of malformation of the telson has not been previously reported for this species.

Reference:
Sadine SE. A remarkable bifid aculeus in Androctonus amoreuxi (Audouin, 1826) from central Algeria (Scorpiones: Buthidae). Revista Iberica de Arachnologia. 2021(38):191-2.

Thanks to Dr. Sadine for sending me his article!

A scorpion with four pectines and other anomalies

Morphological anomalies of scorpions are rare, but a few case have been reported. In a recent papers, Rolando Teruel and José Guadalupe Baldazo-Monsivaiz report of a specimen of Mesomexovis punctatus (Karsch, 1879) (Vaejovidae) from Mexico with a combination of hermaphroditism, gynandromorphism, and pectinal duplication (i.e., presence of four pectines).

Abstract:
In the present note, we describe in detail an aberrant anomalous specimen of the scorpion Mesomexovis punctatus (Karsch, 1879) (Vaejovidae). This strange individual is an adult and exhibits a combination of hermaphroditism, gynandromorphism, and pectinal duplication (i.e., presence of four pectines); the latter represents the first report ever made of such teratology. It was collected by the authors in northeastern Guerrero State, Mexico.

Reference:
Teruel R, Baldazo-Monsivaiz JG. Hermaphroditism, Gynandromorphism, and Four Pectines: an Extreme Case of Developmental Anomaly in Scorpions (Scorpiones: Vaejovidae). Euscorpius. 2015 (197):1-7. [Open Access]

Thanks to Rolando for sharing this very special discovery with me a few weeks ago!

Two-tailed scorpions

Two-tailed female Centruroides nitidus with scorplings on her back.

Body malformations and anomalies in scorpions are reported from time to time. One of the most famous cases was Pepe - The two-tailed scorpion (a Centruroides excilicauda with two tails). In a recent article, Michael Seiter and Rolando Teruel report of two more cases of metasomal duplication (two-tailed scorpions). Interestingly, the female Centruroides nitidus (Thorell, 1876) with two tails grew up, mated and got offspring.

Abstract:
Herein we report two further cases of metasoma duplication in buthid scorpions: a second instar juvenile Tityus obscurus (Gervais, 1843) and an adult female Centruroides nitidus Thorell, 1876. Both individuals were born in captivity; the former died after its first ecdysis, but the latter reached adulthood and reproduced normally. This represents the first published record of the occurrence of such an anomaly in either species.

Reference:
Seiter M, Teruel R. Two new cases of metasomal duplication in scorpions, with notes on their reproductive biology (Scorpiones: Buthidae). Revista Iberica de Arachnologia. 2014 (24):127-9.

Thanks to Rolando for sending me his article!

A seven-legged scorpion

David David has recently published a paper describing a leg absence anomaly in a female Scorpio maurus fuscus (Ehrenberg, 1829) (Scorpionidae) found in Israel. This is a birth defect and not an injury.

Abstract:
A teratological leg absence anomaly is reported and discussed in a Scorpio maurus fuscus (Scorpionidae) specimen from Israel. In this scorpion, the third right leg is completely missing, and the fourth right leg has a deformed coxa, which abuts the entire lateral edge of the sternum. The area anterior to the sternum is visibly curved to the right. This is the first leg absence anomaly reported in scorpions.

Reference:
David D. A Seven-Legged Scorpion: the First Teratological Leg Absence Found in Scorpio maurus fuscus (Scorpiones: Scorpionidae). Euscorpius. 2012 (151):1-4. [Free full text]

Abnormal pectines in a Vaejovis

Sometimes scorpions with abnormal body parts are discovered. Pepe - The Two-Tailed scorpion is probably one of the most "famous" examples. Richard Ayrey now reports about a Vaejovis lapidicola (Vaejovidae) with abnormal pectines.

Abstract:
Among specimens of Vaejovis lapidicola Stahnke, one female was found to have abnormally shaped pectines, both with only distal pectinal teeth. This rare, possibly teratological anomaly is documented and discussed.

Reference:
Ayrey RF. An anomaly of pectinal organs in Vaejovis lapidicola (Scorpiones: Vaejovidae). Euscorpius. 2011(130):1-6. [Free fulltext]

Body malformations in a few Iranian scorpions

Body malformations and anomalies in scorpions are reported from time to time. One of the most famous cases was Pepe - The two-tailed scorpion (a Centruroides excilicauda with two tails).

Jahanifard and co-workers have now reported cases of pedipalp and telson anomalies in a few Iranian scorpions.

Abstract:
The developmental anomalies are reported in this study. The first and second abnormally are presented in right pedipalps of Paraorthochirus and Orthochirus (Buthidae) while Paraorthochirus pedipalp just includes coxa, trochanter and without other parts (femur, patella, movable and fixed finger). The right pedipalp of Orthochirus specimen has abnormally too; it has all parts of pedipalp except complete fixed finger. In both of scorpions, the left pedipalp is normal. Another case is present in venom vesicle of Hemiscourpius (Hemiscorpiidae). Pictures and morphometric measurements for three specimens are given.

Reference:
Jahanifard E, Navidpour S, Masihipour B. Pedipalps and venom vesicle anomalies in two families of scorpions (Scorpiones: Hemiscorpiidae, Buthidae) from Iran. Pakistan Journal of Biological Sciences. 2008;11 (2):309-11. [Free fultext]