Brotheina Simon, 1879

Soleglad, Michael E. & Fet, Victor, 2003, High-level systematics and phylogeny of the extant scorpions (Scorpiones: Orthosterni), Euscorpius 2003 (11), pp. 1-175 : 100-101

Subtribe Brotheina Simon, 1879 , new rank

Type Genus. Brotheas C. L. Koch, 1837

Composition. This new subtribe is established here. It includes three genera: Brotheas C. L. Koch, 1837 ; Broteochactas Pocock, 1893 (= Auyantepuia González-Sponga, 1978 ; = Taurepania González-Sponga, 1978 , syn. n.; = Cayooca González-Sponga, 1996 , syn. n.; = Guyanochactas Lourenço, 1998 , syn. n.); and Hadrurochactas González-Sponga, 1978 . The genera Cayooca , Guyanochactas , and Taurepania are here synonymized with Broteochactas for the reasons given below. The genus Brotheas remains as originally defined, and there are no changes to its species content. The content of the genus Broteochactas is changed here, as a large number of species are transferred from Broteochactas to the new genus Neochactas (subtribe Neochactina ), and at the same time all species formerly assigned to genera Cayooca , Guyanochactas , and Taurepania are transferred to Broteochactas . The following species are transferred to Broteochactas : from Cayooca : Broteochactas venezuelensis (González-Sponga, 1996) , comb. nov. (type species of Cayooca ); from Guyanochactas : Broteochactas gonzalezspongai (Lourenço, 1988) , comb. nov. (type species of Guyanochactas ); B. gougei Vellard, 1932 , comb. nov.; B. mascarenhasi (Lourenço, 1988) , comb. nov.; from Taurepania : Broteochactas manisapanensis (González-Sponga, 1992) , comb. nov.; B. porosus Pocock, 1900 , comb. nov. (type species of Taurepania ); B. trezzii (Vignoli & Kovařík, 2003) , comb. nov.; B. verneti (González-Sponga, 1992) , comb. nov.; B. vestigialis (González-Sponga, 1978) , comb. nov. The following three species remain in Broteochactas : Broteochactas nitidus Pocock, 1893 (type species), B. gollmeri (Karsch, 1879) , and B. scorzai Dagert, 1957 . Since we consider Hadrurochactas a valid genus (see below), we transfer to this genus three Brazilian species from Broteochactas : Hadrurochactas brejo (Lourenço, 1988) , comb. nov.; H. mapuera (Lourenço, 1988) , comb. nov.; and H. polisi (Monod & Lourenço, 2001) , comb. nov. In addition, one more species not listed in González-Sponga (1996a) and Sissom (2000a), H. machadoi González-Sponga, 1993 , belongs to Hadrurochactas .

Distribution. South America.

Diagnosis. Synapomorphies. Chela trichobothria Db situated close to palm midpoint, Dt well past palm midpoint, distal of trichobothrium Est; chelal trichobothrial series eb–et positioned on finger distal two-thirds; est–esb–eb juncture angles toward fixed finger edge, eb removed from finger edge; chelal Et 5 situated at base or on fixed finger. Important Symplesiomorphies. Neobothriotaxy Ch2 present on ventral surface of patella; neobothriotaxy Ch2 present on external surface of patella; pectinal middle lamellae composed of one or two plates, semi-fused with anterior lamellae, fulcra if present, quite reduced.

Discussion. The genus-level taxonomy of tribe Brotheini is uncertain due to the dubious definition of several genera, which attempt to organize the many species described in the last 25 years. To exasperate this situation, many of these species were defined from few specimens and few localities ( Sissom, 2000a). Although we are not in a position to determine the validity of the 75+ species comprising this subtribe, we do evaluate here the current characters now used to define the various genera comprising this subtribe. We briefly list the diagnostic characters currently used to identify these genera, most of which are derived from keys and diagnoses presented by González-Sponga (1996a), Lourenço (1998d), and Monod & Lourenço (2001).

Genus Brotheas C.L. Koch, 1837 : distinguished by its large, elongated stigmata (González-Sponga, 1996a and Lourenço, 1998d); carapace surface convex, covered with dense granulation and punctation (González-Sponga, 1996a); ventral surface of leg tarsus with well-developed, evenly positioned setal pairs (Lourenço, 1998d).

Genus Broteochactas Pocock, 1893 : distinguished by small, oval to round stigmata (González-Sponga, 1996a and Lourenço, 1998d); carapace surface flat, smooth and shiny (González-Sponga, 1996a); ventral surface of leg tarsus with numerous bristle-like, irregularly positioned setae (González-Sponga, 1996a and Lourenço, 1998d); pectinal teeth number 9–11 (González-Sponga, 1996a).

Genus Cayooca González-Sponga, 1996 : distinguished by eight trichobothria on the patella ventral surface (all characters from González-Sponga, 1996b); carapace broad and flat; ventral surface of leg tarsus with well-developed, evenly positioned setal pairs; stigmata small and oval.

Genus Guyanochactas Lourenço, 1998 : distinguished by oval to round stigmata (all characters from Lourenço, 1998d); ventral surface of leg tarsus with well-developed, evenly positioned setal pairs; 45–65 mm. in length.

Genus Hadrurochactas Pocock, 1893 : distinguished by a subaculear tooth on the telson vesicle (González-Sponga, 1996a and Monod & Lourenço, 2001)); telson vesicle very flat laterally (Monod & Lourenço, 2001); adults not exceeding 24 mm (González-Sponga, 1996a).

Genus Taurepania González-Sponga, 1978 : distinguished by absence of pectinal fulcra (all characters from González-Sponga, 1996a); carapace surface flat, smooth and shiny; ventral surface of leg tarsus with numerous bristle-like, irregularly positioned setae; pectinal teeth number 5–8.

By studying the diagnostic characters listed above, we see that Brotheas is unique with its large slit-like stigmata, a character unprecedented in the families Chactidae , Euscorpiidae , and Superstitioniidae , and only found elsewhere in the chactoids in family Vaejovidae . Therefore, within this special context, the slit-like stigma is an important character. Otherwise, the stigma shape of small, oval to round, cannot be used to separate other genera. Secondary characters distinguishing Brotheas are the granulated and convex carapace surface, and the well-developed evenly positioned setal pairs of the ventral surface of the leg tarsus. However, these two characters are also found in the genus Guyanochactas . Broteochactas is distinguished from Brotheas and Guyanochactas by its bristle-like, irregularly positioned setal pairs of the ventral surface of the leg tarsus, but this condition is also matched in genera Taurepania and Hadrurochactas . Taurepania is stated to have pectinal tooth counts ranging from 5–8, but in the individual species descriptions (González-Sponga, 1996a; Vignoli & Kovařík, 2003), we see a range from 4 to 12 (includes both genders). Also, all five species of Taurepania are lacking pectinal fulcra, potentially a good diagnostic character. However, González-Sponga (1996a) states that fulcra are optionally present in genera Brotheas and Broteochactas thus this cannot be used as a reliable character for Taurepania , especially between it and Broteochactas . Genus Cayooca is defined from a single species based on a single specimen, and its only distinguishable character is an extra accessory trichobothrium on the ventral surface of the patella. Considering its leg tarsus armature, Cayooca is indistinguishable from Guyanochactas , except for this extra trichobothrium. It appears that smaller species in this subtribe have a tendency for more numerous, thinner bristle-like, and irregularly positioned tarsal setae. In the larger species, exemplified by Brotheas , we see a lower number of stouter, more regularly positioned setal pairs. This same trend is also present in the subfamily Chactinae , where the setal pairs are very numerous and elongated in the small genus Vachoniochactas , which also exhibits a reduced to obsolete median spinule row. Genus Hadrurochactas is diagnosed by González-Sponga (1996a) by its small size and “subaculear tooth”. Yet in González-Sponga’s (1996a) figures, we see that H. odoardoi is lacking this structure. However, Monod & Lourenço (2001), referring to this genus as the “schaumii ” group within genus Broteochactas , considered it a legitimate taxonomic group. They included five species, Broteochactas polisi , B. schaumii , B. brejo , B. mapuera , and B. odoardoi . Their depiction of the “subaculear tooth” (their Figs. 5–8) is a much better description of this structure, where they define it as a granulated carina. In our specimen of H. schaumii , we see five delicate irregular granulated carinae extending along the ventral surface of the telson vesicle, the median carina with slightly elongated spines, extending to the vesicle/aculeus juncture, the so-called “subaculear tooth”. In addition to these granulated carinae, the vesicle of these species is quite flat when viewed laterally. Interestingly, we see an analogous situation with the equally small chactine genus Vachoniochactas which also exhibits a median carina on the ventral surface of the vesicle, terminating in a series of 1–2 pointed granules at the vesicle/aculeus juncture, also termed a “subaculear tooth” by González-Sponga (1978).

Based on the consistency within these unique characters across several species, we consider Hadrurochactas a valid genus as originally recognized by Pocock (1893) and listed in Sissom (2000a). In addition, we also recognize Brotheas and Broteochactas as valid, comprising the stem genera of this subtribe. However, we do not believe Guyanochactas (which is nothing but a large Broteochactas with well-developed tarsal setal pairs), Taurepania (which is not adequately separable from Broteochactas ), and Cayooca (which is based on a single specimen) are valid genera, and therefore synonymize all three with genus Broteochactas .