Somalicharmus whitmanae Kovařík, 1998, Kovarik, 1998

Kovařík, František, Lowe, Graeme & Šťáhlavský, František, 2016, Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part IX. Lanzatus, Orthochirus, and Somalicharmus (Buthidae), with description of Lanzatus somalilandus sp. n. and Orthochirus afar sp. n., Euscorpius 232, pp. 1-38: 19-34

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4553AE99-6098-4764-8227-AAD8427739D6

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lsid:zoobank.org:pub:4553AE99-6098-4764-8227-AAD8427739D6

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http://treatment.plazi.org/id/DB2887AB-FFEA-E145-EFAD-F936FB71A264

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Felipe

scientific name

Somalicharmus whitmanae Kovařík, 1998
status

 

Somalicharmus whitmanae Kovařík, 1998  

( Figs. 78–122, 125–155, Table 2)

Somalicharmus whitmanae Kovařík, 1998: 116   , 119– 122, figs. 9–15; Fet & Lowe, 2000: 224; Kovařík, 2003: 135, 145; Fet et al., 2005: 14; Kovařík & Whitman, 2005: 112.

TYPE LOCALITY AND   TYPE REPOSITORY. Ethiopia (see comments below), El Meti   ; MZUF No. 534.

T YPE MATERIAL EXAMINED. Ethiopia, El Meti , 04°58'N 37°08'E, 1♂ (holotype), 1939, leg. E. Zavattari GoogleMaps   , MZUF No. 534.

ADDITIONAL MATERIAL EXAMINED. Ethiopia, Southern Nationalities and Peoples Region Federal State ( SNNPR), Turmi , 04°58'32"N 36°30'53"E, 908 m a.s.l. (Locality No. 16EA, Fig. 153), 17♂ 2juvs GoogleMaps   ., 9.-11. IV. 2016, leg. F. Kovařík, FKCP; SNNPR, 20 km SE Konzo , 05°14'33"N 37°32'06"E, 839 m a.s.l. (Locality No. 16EF, Fig. 154) GoogleMaps   , 14.-15. IV.2016   , 29♂ 2♀ (ecdysis 3. VI.2016) 2juvs., leg. F. Kovařík, FKCP.

ADDITIONAL DESCRIPTION (BOTH SEXES). Total length of males 18.5– 25 mm, females 19–23.5 mm. Pedipalps stout, movable chela finger shorter than manus in both sexes ( Figs 94 and 104). Manus of pedipalp chela and metasoma of male broader than in female ( Figs. 9 3–95, 102–105 and 78–81). Sternites smooth ( Fig. 122). Pectine teeth number 11–14 (5 x 11, 43 x 12, 36 x 13, 1 x 14) in males and 11–12 (1 x 11, 3 x 12) in females. Metasoma I with lateral carinae present only in females ( Fig. 87), and weakly developed or indicated in males ( Fig. 83). All metasomal segments with dorsal median trough and two lateral carinae composed of several large, non-contiguous, mutually distant granules whose size increases progressively with each consecutive segment.

C HELICERA. ( Figs. 125–128). Manus relatively slender, 1.5 times longer than wide, dorsal surface smooth, anterior area with scattered granules and 11 short and long, pale setae, anterior marginal and dorsointernal carinae absent. Dorsal surface of movable finger smooth, with 3 long and 3 short pale setae; dorsal surface of fixed finger with proximal dense brush of long setae with fluorescent bases. Ventral surfaces of manus, fixed and movable fingers bearing dense brush (scopula) of long setae with fluorescent bases ( Fig. 128), arranged in distinct wedge-shaped field with V-shaped proximal border on manus. Fingers elongated, with reduced dentition ( Figs. 125–126) departing markedly from typical buthid pattern (Vachon, 1963). Movable finger dorsal margin armed with 5 teeth: dorsal distal tine, subdistal, median, and 2 very small basal teeth not fused in bicusp; ventral margin unarmed except for ventral distal tine, which clearly exceeds dorsal distal tine in length. Fixed finger margin armed with 3 teeth: distal tine, subdistal, and basal, bicusp absent; all teeth sharp, conical, non- contiguous and well separated from each other. Ventral surface of both fixed and movable fingers unarmed.

HEMISPERMATOPHORE ( Figs. 129–133). Flagelliform, extremely long and slender, trunk ca. 18 times length of capsule region. Flagellum relatively short, unfolded length ca. 50% of trunk length, folded into pars recta and pars reflecta, cylindriform, gradually tapering, not distally dilated. Capsule region with 3 lobes at base of flagellum in 2+1 configuration (Kovařík et al., 2016c): median lobe (ml) narrow, tapering to sharp apex, with dark reddish-black well-sclerotized carina, well separated from base of flagellum; internal lobe (il) smaller, paler brown, deeply split from median lobe and even narrower, also finely tapered to a sharp point; basal lobe (bl) greatly enlarged, relatively broad, protruding vertically, sclerotized brown color, apically curled in forward (distal) direction, terminus blunt and rounded; margins of basal lobe stalk also curled forward forming concave scoop, with internal margin extending forward to connect with secondary sclerotized carina along internal margin of median lobe. The peculiar structure of the basal lobe is not an anomaly, as it was confirmed by examination of 10 hemispermatophores extracted from 5 males.

SETATION. Metasomal segments with sparse, long, dark macrosetae and short, fluorescent microsetae. Telson with numerous long, dark macrosetae, sparse short, fluorescent microsetae, and numerous long, pale, fluorescent setae concentrated on posterior ventral surface of vesicle ( Figs. 90–92). Pedipalp chela ( Figs. 110–111) with uniformly distributed cover of short fluorescent microsetae over surfaces of manus and fingers. Short dark setae also present but sparse, mostly located on pedipalp fingers. Pectines ( Fig. 112) with numerous longer, dark macrosetae mostly on marginal and basal middle lamellae. Numerous medium to short fluorescent setae on middle lamellae and most distal pectine tooth. Fulcra equipped with unusually dense array of ca. 15–30 fluorescent microsetae.

A FFINITIES. The genus name was originally coined to suggest that Somalicharmus   might have affinities with the Indian genus Charmus   , and its relative Thaicharmus (Kovařík, 1998)   , which like Somalicharmus   are small dark scorpions with robust metasoma and subpentagonal sternum. Fet et. al. (2005) grouped these three genera in the “ Charmus   ” group based on dorsal position of femur trichobothrium d 2. However, in our samples we have observed d 2 to also be found internal to the dorsointernal carina, a sufficient criterion for placement in the “ Uroplectes   ” group (Fet et. al., 2005). The telson of Somalicharmus   differs from that of Charmus   , but is similar to that of another small buthid in the “ Uroplectes   ” group, Butheoloides   , both being bulbous with a small, knob-like subaculear tubercle (but a similar tubercle occurs in Thaicharmus   ). However, Somalicharmus   differs from Butheoloides   in other characters (e.g. cheliceral finger dentition, placement of trichobothria db, dt and it on pedipalp fixed finger, form of pedipalps and metasoma). Also, unlike Somalicharmus   , both Charmus   and Butheoloides   have a hemispermatophore median lobe that is fused to the base of the flagellum ( Vachon, 1952; Kovařík et. al., 2016c). The absence of teeth on the ventral side of the cheliceral fixed finger of Somalicharmus   is shared with other buthid genera Nanobuthus   , Uroplectes   and Karasbergia   . The genus Nanobuthus   needs revision, but if, as some authors have presumed, it is close to Neobuthus   , then it would have femur trichobothria in the β -configuration and belong to the “ Buthus   ” group (Fet et. al., 2005) which excludes Somalicharmus   . On the other hand, Somalicharmus   is similar to Uroplectes   and Karasbergia   in having femur trichobothria in α -configuration and femur d 2 displaced internally (= “ Uroplectes   ” group), and a 2+1 layout of lobes of the hemispermatophore capsule, with the median lobe not fused to the base of the flagellum (Kovařík et. al., 2016; Lamoral, 1979). Uroplectes   differs from Somalicharmus   in its subtriangular sternum shape, trichobothrial pattern, pedipalp and metasomal structure. In Uroplectes   , it is the basal tooth of the female pectine that is enlarged, not the basal middle lamella. Karasbergia   shares several characters with Somalicharmus   : both have a subpentagonal sternum, pedipalp fixed finger with trichobothrium it at a non-distal location (near mid-finger in Karasbergia   ) and db and dt in proximal positions, and metasoma I–III with ventrolateral carinae joined to form a U-shaped posterior marginal carina (Hewitt, 1913; Lamoral, 1979; Prendini 2004). Karasbergia   differs in having 3 pairs of lateral eyes, pedipalp chela manus with trichobothrium V 2 internal to V 1, pedipalp fingers without external accessory granules, genital papillae absent in males, and chelicera with standard buthid pattern of carination and dentition ( Lamoral, 1979; Vachon, 1963). The strongly dilated basal middle lamella of female pectines in Somalicharmus   is an unusual condition also found in

Figures 134–148: Somalicharmus whitmanae   . Mitotic metaphases (134, 137, 140, 143, 146), postpachytenes (135, 138, 141, 144, 147), and ideograms (136, 139, 142, 145, 148) (y axis - % of the chromosome length of the diploid set, dark grey indicates chromosomes of multivalents) of males. Figures 134–136. Male from locality 16EA, 2n=20, 10II. Figures 137–139. Male from locality 16EA, 2n=20, 8II+CIV. Arrows indicate chromosomes of quadrivalent. Figures 140–142. Male from locality 16EF, 2n=16, 10II. Figures 143–145. Male from locality 16EF, 2n=20, 7II+CVI. Arrows indicate chromosomes of hexavalent and asterisk indicates extra large chromosome. Figures 146–148. Male from locality 16EF, 2n=21, 9II+CIII. Arrows indicate chromosomes of trivalent and arrowheads indicates extra small chromosome. Scale bar = 10 µm.

Isometrus   (fig. 558 in Kovařík et al., 2016c), Parabuthus   (fig. 62 in Kovařík et al., 2016b), Tityopsis   (fig. 49 in Teruel et Kovařík, 2012), and “ Tityus asthenes   ” complex (fig. 14 in Kovařík et al., 2013b), but these taxa are not closely related and this is probably a convergent character.

Unique traits of Somalicharmus   not known in any other extant buthids include: (i) absence of dentition on ventral margin of the cheliceral movable finger; (ii) absence of bicuspid dentition on base of cheliceral fixed finger; (iii) cheliceral manus without anterior marginal or dorsointernal carinae; (iv) pedipalp chela with trichobothrium it located at base of fixed finger (as far as has been documented; many species descriptions failed to map the location of it); (v) hemispermatophore capsule with tall, vertical, scoop-like basal lobe which is as long as the median lobe.

REMARKS ON THE KARYOTYPES (Figs. 134–148). Altogether we analyzed karyotypes of eight males of Somalicharmus whitmanae   from the two localities 16EA and 16EF ( Table 2). For chromosome preparations we used the “plate spreading” method already used for scorpions (e.g. Kovařík et al., 2009). The chromosomes were stained by 5% Giemsa solution in Sörensen phosphate buffer for 20 min. The relative length of the chromosomes of the diploid set was measured for each specimen using the software Image J 1.45r (http://rsbweb. nih.gov/ij) with the plugin Levan (Sakamoto & Zacaro, 2009) based on 10 postpachytene.

Seven males analyzed from both localities displayed 2n=20 (Figs. 134–145). We also detected fission of one chromosome in one male from locality 16EF (Fig. 147). This chromosomal aberration causes an increase in diploid number (2n=21) and the presence of a distinct small chromosome (Figs. 146–148). The chromosomes form bivalents during pachytene and postpachytene in the majority of males (Figs. 135 and 141). These chromosomes gradually decrease in length with the exception only of the last chromosome pair that is distinctively shorter than the previous one (Fig. 136, Table 2). This shorter pair of chromosomes is also evident in karyotypes of all other males with detected chromosomal rearrangements. In one male from 16EA, we observed a quadrivalent during postpachytene (Fig. 138). This is probably the result of reciprocal translocation between two chromosome pairs of larger length (Fig. 139). In one male from locality 16EF, we observed a hexavalent during postpachytene (Fig. 144), probably the result of several rearrangements. In the karyotype of this specimen, the rearrangements form one extra large chromosome (Figs 143–145). The karyotypes of S. whitmanae   show holocentric chromosomes, achiasmatic meiosis in males, and a lower number of chromosomes. These are attributes typical for scorpions of the family Buthidae   (e.g. Mattos et al., 2013).

COMMENTS ON LOCALITIES AND LIFE STRATEGY. The type locality has been confirmed to be in Ethiopia, thanks to Sarah Whitman who found that the label " Somalia: El Meti" is incorrect (Kovařík & Whitman, 2005: 112). The male holotype was collected by the Missione Biologica Sagan-Omo led by Edoardo Zavattari, which in 1939 explored the Borana region from Dolo westwards to Lake Stephanie and the Omo River ( Largen, 2001). According to Largen (2001), El Meti is located at 04°58'N 37°08'E, midway between localities 16EA and 16EF ( Fig. 155).

The first author visited locality 16EA ( Fig. 153) on 9–11 April 2016 and collected 17 males and 2 juveniles by UV detection. Here, the maximum recorded daytime temperature was 33.8 ºC, and the nighttime temperature shortly after sunset was 27.1 ºC, dropping to 24.3 ºC (minimum temperature) before sunrise, and the humidity varied at night between 55% and 72%. The minimum daytime humidity was 40%. In addition to S. whitmanae, The   first author also recorded at this locality Hottentotta trilineatus (Peters, 1862)   , Lychas obsti Kraepelin, 1913   , Parabuthus pallidus Pocock, 1895   , Uroplectes fischeri (Karsch, 1879)   , and Pandinurus exitialis (Pocock, 1888)   .

The first author visited locality 16EF ( Fig. 154) on 14–15 April 2016 and collected by UV detection 29 males, one gravid female which gave birth to 13 newborns on 9 July 2016 ( Figs. 151–152, these newborns completed their first ecdysis on 17 July 2016), and 3 juveniles of which one completed final ecdysis to a sexually mature female on 3 June 2016. At this locality, the maximum recorded daytime temperature was 34.7 ºC, and the nighttime temperature was 27.4 ºC shortly after sunset, dropping to 21.7 ºC (minimum temperature) before sunrise, and the humidity varied between 55% and 65%. In addition to S. whitmanae   the first author also recorded at this locality Hottentotta trilineatus   , Lychas obsti   , Parabuthus hamar Kovařík et al., 2016   (type locality), and P. pallidus   .

MZUF

Museo Zoologico La Specola, Universita di Firenze

T

Tavera, Department of Geology and Geophysics

VI

Mykotektet, National Veterinary Institute