Grosphus, Simon, 1880

Lowe, Graeme & Kovařík, František, 2019, Review of Grosphus Simon 1880 with description of Teruelius gen n a new buthid genus from Madagascar (Scorpiones Buthidae), Euscorpius 281, pp. 1-128 : 5

Diagnosis of the ‘ Grosphus ’ group

The three buthid genera Grosphus Simon, 1880 , Neogrosphus Lourenço, 1995 , and Teruelius gen. n. comprise a distinct assemblage of Madagascar buthids (= ‘ Grosphus ’ group) sharing the following set of characters:

Carapace subrectangular, weakly trapezoidal or nearly parallel-sided, surface densely granular, carinae indistinct except for superciliary carinae; frontal region of carapace flat, not sloped towards anterior margin; median eyes large, median ocular tubercle prominent, located forward of the carapace centroid ( Figs. 165–180); 5 pairs of lateral eyes (3 large, 2 small) ( Figs. 227–230); chelicerae with typical buthid dentition on fixed and movable fingers ( Vachon, 1963), two enlarged denticles on ventral surface of fixed finger ( Figs. 231– 238); sternum type 1, subtriangular; tergites granular, tergites I– VI with single, weak median carina, tergite VII with weak median carina and 2 pairs of strong lateral carinae; metasoma moderately elongate, segments I– III with 8–10 carinae, IV with 8 carinae, V with 3–5 carinae; telson vesicle bulbous, ovoid or elongate, with or without subaculear tubercle ( Figs. 181–195); pectines with fulcra, 13–41 teeth, female with basal pectinal tooth dilated or elongated, lacking peg sensillae ( Figs. 40–51, 196–210); hemispermatophore flagellum thicker at base, narrowed proximally, thickened distally ( Figs. 52, 58, 60, 67, 71, 75, 78, 84); pedipalp chela elongate, smooth, carinae obsolete, surface typically with numerous short macrosetae ( Figs. 21–24); finger dentition composed of 8–15 discrete linear rows of granules or denticles, each slightly oblique with proximal ends directed externally; rows either non-overlapping or slightly imbricated, proximal 3 granules in each row enlarged, 2 of these slightly displaced outwards as ‘external accessory’ granules; series of large, dentate internal accessory granules present, offset from main rows; both chela fingers with enlarged apical teeth, 3–4 external subdistal granules; pedipalps sexually dimorphic, dentate margins of fingers weakly or strongly scalloped proximally in males, straight in females, manus of males broader than that of females; trichobothrial pattern orthobothriotaxic, type A ( Vachon, 1974), with femur d 1 - d 3 - d 4 in α-configuration ( Vachon, 1975), patella d 3 external to dorsomedian carina ( Fet et al., 2005); patella em much closer to est and et, than to esb 1 and esb 2, with em -est -et usually forming a compact triad ( Figs. 345, 481a); chela manus with Eb 1 - Eb 2 angled distally, Eb 1 - Eb 2 - Eb 3 acute angle opening in proximal direction (γ-configuration) ( Figs. 342, 478a); chela with db in proximal half to middle of fixed finger; legs III –IV with tibial spurs ( Figs. 211–226, 261–262, 318–319, 364–365, 414–417, 487–488, 514–515, 540–541, 578–579, 618–619), tarsi without bristle-combs.

REMARKS. In describing the first ‘ Grosphus ’ group species, Scorpio (Androctonus) madagascariensis, Gervais (1844 : pl. XI, fig. 3) illustrated the carapace showing forward placement of the median eyes, and also accurately depicted five pairs of lateral eyes, now recognized to be the prevalent buthid configuration ( Loria & Prendini, 2014; Yang et al., 2013). In spite of this, Fage (1929) incorrectly declared that Grosphus (sensu lato) only bore 3 pairs of lateral eyes, and Lourenço (1996b) cited only 3–4 pairs. Moreover, only 3 pairs were described for: Grosphus ambre , G. darainensis , G. garciai , G. goudoti , G. halleuxi , G. hirtus , G. madagascariensis , G. makay , G. mandena , G. mayottensis , G. polskyi , G. rossii , G. simoni , G. rakotoariveloi , G. tavaratra , G. voahangyae , Teruelius ankarana , T. ankarafantsika , T. bemaraha , T. bicolor , T. bistriatus , T. eliseanneae , T. feti , T. ganzhorni , T. intertidalis , T. limbatus , T. magalieae , T. mahafaliensis , T. olgae , T. sabineae , T. waeberi ( Lourenço, 1996b, 1999, 2001b, 2003c, 2005, 2012c, 2013b, 2014; Lourenço & Goodman, 2006, 2009; Lourenço & Wilmé, 2015a, 2015b, 2016; Lourenço et al., 2004, 2007a, 2009b, 2016c, 2017, 2018b). We confirm here that 5 pairs are indeed present in all species that we have examined: G. garciai (= G. hirtus ), G. goudoti , G. ‘ halleuxi ’, G. hirtus , G. sp. nr hirtus , G. madagascariensis , G. ‘ mandena ’, G. voahangyae , Neogrosphus griveaudi , Teruelius ankarafantsika , T. ankarana , T. annulatus , T. bistriatus , T. feti , T. flavopiceus , T. grandidieri , T. intertidalis , T. limbatus , T. mahafaliensis and T. olgae (e.g., Figs. 227–230). We found only a few individual deviations from the standard pattern, such as 2 large and 2 small ocelli, that we regarded as developmental anomalies. We predict that other ‘ Grosphus ’ group species will also comply with the 5-eye pattern. Although undercounting of lateral eyes is perhaps attributable to overlooking of the smaller posterior and upper ocelli, 10 of the published 3-eye counts post-date introduction of the 5-eye model by Yang et al. (2013, coauthor Lourenço) and Loria & Prendini (2014). Paradoxically, Lourenço et al. (2007a) claimed 3 lateral eyes in boilerplate descriptions of G. hirtus and G. polskyi , yet their figures clearly depict all 5 lateral eyes as being present in both species. Vachon (1969) correctly reported 5 “nettement visibles” lateral eyes, 3 large and 2 small, in both sexes of Neogrosphus griveaudi . Although 3 pairs were described for N. blanci and N. andrafiabe ( Lourenço, 1996b; Lourenço et al., 2015), we are skeptical that these counts are accurate.