Tityus tayrona Lourenço, 1991

Teruel, Rolando & Roncallo, César A., 2010, Rare or poorly known scorpions from Colombia. IV. Additions, synonymies and new records (Scorpiones: Buthidae, Scorpionidae), Euscorpius 105 (105), pp. 1-15 : 4-8

Tityus tayrona Lourenço, 1991

Figs. 3–7 , 12

Tityus tayrona Lourenço, 1991a: 275 , 279–281, figs. 3– 4, tabs. 1–2; Rojas-Runjaic & Armas, 2002: 63; Botero-Trujillo & Fagua, 2007: 129–130, 132–133, figs. 11–15.

Tityus erikae Lourenço, 1999: 1–6 , figs. 1–7, tab. I. New synonym.

Diagnosis (emended): species of small size (males 33–41 mm, females 35–38 mm) for the genus. Body light yellowish brown, very densely spotted with light to medium brown, tergites with three very irregular dark stripes (better defined in females and juveniles); metasomal segments I–V similarly colored (i.e., V not conspicuously darkened), telson dark reddish brown; pedipalp fingers densely spotted, in adult males with basal portion subtly infuscate. Pedipalp chela and metasomal segment V inflate and moderately globular in larger males. Sternite V with a smooth whitish patch in both sexes: always small and flat in the adults (smaller in females), but expanded and bulky in juvenile males. Dorsolateral carinae of metasomal segments II–IV with distal tooth not conspicuously enlarged. Telson vesicle feebly granulose; subaculear tubercle large and rhomboidal, with two large dorsal granules. Pedipalp fixed finger with 13–14 principal rows of granules, movable finger with 14–15; basal lobe/notch combination vestigial in males, absent in females. Pectinal tooth count 16–19 in males, 14–18 in females; basal middle lamella not dilated.

New Records: COLOMBIA: Bolívar Department, Turbaco, Urbanización La Granja, 31 December 2008, leg. C. A. Roncallo, R. Roncallo & J. A. Vargas, 1♂, 1♀ (Sco-0413); Turbaco Botanical Garden, 7 October 2008, leg. C. A. Roncallo & R. Roncallo, 1 juvenile (Sco- 0414) .

Remarks: the adult specimens were collected among rocks and rotten logs during a night search with UV light (02:30 hrs), in an area which had been cleared for building purposes at an altitude of 100 m a.s.l. The juvenile was found among bracts of Heliconia flowers.

In a previous paper, Teruel & García (2008b: 10– 12) commented on the deep taxonomic problems of the Colombian members of the “ Tityus clathratus ” speciesgroup, and made a special reference to inadequate or unreliable diagnoses of most species, including T. tayrona and T. erikae . Additional specimens studied herein allow updating and correcting the diagnosis of the former according to the current taxonomy of this group. It is worth to note here that the presence of a smooth patch in sternite V is now confirmed for both sexes of T. tayrona , as previously suggested by Teruel & García (2008: 12). This patch is small and flat in the adult male ( Fig. 4d ), and even less conspicuous in adult female ( Fig. 6d ); thus, it is obvious that it was simply overlooked by these authors in their specimens; this is even demonstrated in the paper by Botero-Trujillo & Fagua (2007), where this patch is explicitly stated to be absent in text page 133, but is in turn clearly shown in the figures 13 and 15 of the same paper.

On the other hand, Tityus erikae was described by Lourenço (1999) on the basis of a single juvenile male, and it was originally separated from T. tayrona on the basis of only three supposedly diagnostic characters: “... a more intense and darker pigmentation generally, a greater distance between median eyes, [...] and the presence of a smooth and shining expanded zone on the posterior region of sternite V ...” (Lourenço, 1999: 2; italics herein added). Juvenile Tityus have no taxonomic value at all, because they lack secondary sexual dimorphism which is critical to diagnose closely related species, and this fact alone renders both Lourenço’s diagnosis and selection of the holotype of T. erikae useless. Apart from this, the first two characters used by Lourenço are largely known to vary from juvenile through adult instars in all species of Tityus and thus cannot be used as diagnostic, so we are only left with character 3 to separate T. erikae from T. tayrona . The examination of the additional specimens of T. tayrona herein recorded (which are all clearly conspecific) confirmed that the smooth patch of sternite V is also present in T. tayrona , and that it is ontogenetically variable: in males it is expanded and bulky in the juvenile instars (see our Fig. 7c , which shows a patch identical to that depicted in Lourenço [1999: fig. 6] for the holotype of T. erikae ), and it becomes much smaller and flat in the adult instar (see our Figs. 4d and 6d ). Apart from this, the juvenile male T. tayrona studied herein matches every point of the original description and figures of T. erikae exactly and the distribution of both taxa is also coincident, demonstrating that the holotype of the latter is merely a juvenile T. tayrona . Thus, the following synonymy is herein established: Tityus tayrona Lourenço, 1991 = Tityus erikae Lourenço, 1999 , new synonym.

On the other hand, some wrong information that has been published on T. tayrona needs to be corrected. First, Rojas-Runjaic & Armas (2002: 63) stated that “ ... male [...] has metasoma with the fifth segment [...] blackish... ” (original text in Spanish, translation and italics added), but this is incorrect according to the original description (Lourenço, 1991a: 280–281, figs. 3– 4), additional illustrated papers (Lourenço, 1997: 66, figs. 3–4; Botero-Trujillo & Fagua, 2007: 132–133, figs. 12–15), and our specimens ( Figs. 3a–b , 4f ).

Second, Botero-Trujillo & Fagua (2007: 133) stated that “ ... this species is characterized by the presence of 14–17 pectinal teeth... ”, but this only applies to females as given in the original description by Lourenço (1991a: 281; tab. 2), which also gives a range of 16–19 for males; our specimens confirm Lourenço's original data, and also allow to know that females may present up to 18 pectinal teeth.

Figures

Figure 3: Adult male of Tityus tayrona from Turbaco: a) entire dorsal view; b) entire ventral view.

Figure 4: Adult male of Tityus tayrona from Turbaco: a) carapace; b) pedipalp, dorsal view; c) sternopectinal region; d) sternite V; e) metasomal segments I–III, lateral view; f) metasomal segments IV–V and telson, lateral view.

Figure 5: Adult female of Tityus tayrona from Turbaco: a) entire dorsal view; b) entire ventral view.

Figure 6: Adult female of Tityus tayrona from Turbaco: a) carapace; b) pedipalp, dorsal view; c) sternopectinal region; d) sternite V; e) metasomal segments I–III, lateral view; f) metasomal segments IV–V and telson, lateral view.

Figure 7: Juvenile male of Tityus tayrona from Turbaco: a) entire dorsal view; b) entire ventral view; c) sternite V.

Figures 12–13: 12 (top). Geographical distribution of Tityus tayrona: previous records (black squares), new record (white square), records previously assigned to T. erikae (white squares with black dot). Abbreviations for Departments: Atl. = Atlántico, Magd. = Magdalena. 13 (bottom). Geographical distribution of Tarsoporosus macuira: previous records (black squares), new record (white square).