Tityus azari Lourenço, 2013

Teruel, Rolando, 2017, Some taxonomic corrections to the genus Tityus C. L. Koch, 1836 (Scorpiones: Buthidae) in Hispaniola, Greater Antilles, Euscorpius 242, pp. 1-9 : 5-7

publication ID

https://doi.org/ 10.18590/euscorpius.2017.vol2017.iss242.1

publication LSID

lsid:zoobank.org:pub:8DDAE09C-4DCD-4E29-A826-86A73BDD9F34

persistent identifier

https://treatment.plazi.org/id/280287CC-FFD1-FFA2-AF1E-AAF80121F9E5

treatment provided by

Carolina

scientific name

Tityus azari Lourenço, 2013
status

 

and Tityus azari Lourenço, 2013

Figure 5 View Figure 5

Type Data. " Dominican Republic. Precise amber mine not confirmed. Lower Oligocene to Upper Eocene" [sic], juvenile ♂ holotype of T. hartkorni (private collection of Joachim Hartkorn, not examined), juvenile ♂ holotype of T. azari (private collection of Jörg Wun- derlich, not examined). Note: Lourenço (2009: 4; 2013: 4) identically declared imprecise geographic and stratigraphic origins for both holotypes, as literally quoted above.

Remarks. The holotypes of both species were not available for study, but fortunately, their original descriptions include good-quality color photographs that allow a satisfactory interpretation of the main diagnostic characters. First, two of them warrant their membership in the "crassimanus" species-group: pedipalp fingers with 14–15 principal rows of denticles and pectines with 19–20 teeth. These counts are within the diagnostic ranges given for this group by Teruel & Armas (2006) and exclude them from the "quisqueyanus" speciesgroup as diagnosed by Armas & Abud Antun (2004): 11–15 principal rows of denticles and 19–20 pectinal teeth, vs. 10–12 principal rows of denticles and 8–15 pectinal teeth, respectively. Moreover, the elongateslender habitus (especially pedipalps, legs and metasoma) of both T. hartkorni and T. azari holotypes is also unambiguously diagnostic for the "crassimanus" speciesgroup, as opposite to the short-stocky habitus of the "quisqueyanus" species-group ( Fig 5 View Figure 5 ).

As pointed out elsewhere (Kovařík et al., 2016a–c; Lowe & Kovařík, 2016; Prendini, 2016) for other papers authored by Wilson R. Lourenço, both original descriptions are flawed by false and/or incorrectly described characters, plus drawings of an inadmissible, poor quality and thus, must be discarded as unreliable except for the photographs (when included). A perfect example is found here: the main character used by Lourenço (2009, 3013) to support these allegedly new taxa and their infra-generic relationships resides in the pectinal fulcra, being described as vestigial to obsolete in T. hartkorni and absent in T. azari . Even on this basis alone, Lourenço (2009) placed T. hartkorni in the strictly Amazonian, controversial subgenus Tityus (Brazilotityus) , without giving any biogeographical argument to support such an odd assignment. Nevertheless, when the photographs published by Lourenço (2009: fig. 8; 2013: fig. 2) are zoomed-in, the pectinal fulcra become clearly visible as normally developed at least in the right-side pecten of both T. hartkorni and T. azari holotypes.

The third fossil member of the genus known from Hispaniola is Tityus geratus Santiago-Blay et Poinar, 1988 , but it presents a very different situation. It was described also from a juvenile male holotype of similar size (apparently second-instars in all three cases), but as opposite to both previous cases, it has precise geographic and stratigraphic origins (La Toca amber mine, in Puerto Plata Province), and its description is correctly written, accurately discussed and satisfactorily illustrated. Thus, the only issue that remains to be addressed is its infra-generic assignment. Based upon the same characters discussed in the previous paragraph (see above), it is clearly another member of the "crassimanus" species-group: pedipalp fingers with 12– 14 principal rows of denticles, pectines with 18–19 teeth, and elongate-slender habitus (Santiago-Blay & Poinar, 1988).

Once the infra-generic position of these three taxa is established, it becomes clear that they closely match each other in all diagnostic characters such as size, degree of attenuation, carination and intercarinal sculpture of body and appendages, counts of principal denticle rows on pedipalp fingers and pectinal teeth. Therefore, the conclusion is obvious: all three holotypes are conspecific and the valid name corresponds to the oldest available synonym. Thus, the following synonymies are herein established: Tityus geratus Santiago- Blay et Poinar, 1988 = Tityus (Brazilotityus) hartkorni Lourenço, 2009 , new synonym = Tityus azari Lourenço, 2013 , new synonym.

It is worth to mention here that this discovery does not represent an isolate case. Recently, the amber-fossil arachnid fauna of Hispaniola has been shown to be actually overestimated and abundant synonymies have been demonstrated after detailed studies, see for example Penney (2001).

General Remarks

After these changes, the diversity and distribution patterns of the genus Tityus in Hispaniola are set as follow. First, the "quisqueyanus" species-group is typical from and well diversified in the Central Range with six species ( T. abudi , T. altithronus , T. bellulus , T. elii , T. kindli , and T. quisqueyanus ), but also has single-species' peripheral occurrences in the Neiba ( T. neibae ) and Northern Ranges ( T. portoplatensis ). On the other hand, the "crassimanus" species-group has a single allopatric species in every major mountain range: T. crassimanus in Bahoruco Range, T. ottenwalderi in the Central Range, and one still-undetermined species in the Northern Range (Armas & Teruel, 2006; R. Teruel, unpublished data).

In addition, the data personally gathered in the field by the present author revealed that their ecological preferences also differ markedly. All members of the "crassimanus" species-group are microhabitat-specific, but habitat-generalist: they are always strictly arboreal, but widespread across all altitude ranges and vegetation types. As opposite, the members of the "quisqueyanus" species-group are microhabitat-generalist, but habitatspecific: they occur indistinctly in the ground and trees, but only in particular vegetation types and altitude zones, i.e., T. abudi , T. elii , T. neibae , and T. portoplatensis live in lower, humid broadleaf forests (350– 2,400 m a.s.l.), while T. altithronus , T. bellulus , T. kindli , and T. quisqueyanus occupy mostly higher, drier pine forests (1,800 –3,185 m a.s.l.).

The Hispaniolan amber-fossil members of the genus have now decreased to a single species, which also belongs in the "crassimanus" species-group. This is also consistent with its chorology, i.e., this group is widespread in most main mountain ranges of the island, but composed of highly microhabitat-specialized taxa; such combination suggests a very ancient origin.

The present corrections set the list of extant and fossil Tityus species from this Greater Antillean insular territory to 10 and 1, respectively, plus another extant taxon that remains undetermined due to unavailability of adequate samples. It follows below, with the updated distribution of every species in each country (HA = Haiti, DR = Dominican Republic) and their upper-level political divisions (Départements in Haiti, Provinces in Dominican Republic); new records were marked in boldface and tentative records in question mark:

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Scorpiones

Family

Buthidae

Genus

Tityus

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