Compsobuthus eritreaensis Kovařík, Lowe, Plíšková et Šťáhlavský, 2016

Kovařík, František, Lowe, Graeme, Plíšková, Jana & Šťáhlavský, František, 2016, Scorpions of the Horn of Africa (Arachnida: Scorpiones). Part VI. Compsobuthus Vachon, 1949 (Buthidae), with a description of C. eritreaensis sp. n., Euscorpius 226, pp. 1-21 : 3-11

Compsobuthus eritreaensis Kovařík, Lowe, Plíšková et Šťáhlavský , sp. n.

( Figs. 5–14, 27–44, 47–60, 77, Table 1) http://www.zoobank.org/urn:lsid:zoobank.org:act:63

3AEAE4-4650-4099-B572-62C7EE3341C1

? Compsobuthus abyssinicus: Kovařík & Whitman, 2005: 107 (in part).

TYPE LOCALITY AND TYPE REPOSITORY. Eritrea, near Massawa , 15°36'58.7"N 39°22'32.8"E, 74 m a.s.l., 4.- 5.XI.2015, (Locality 15 EI, Fig. 56) , first author’s collection ( FKCP).

TYPE MATERIAL. Eritrea, near Massawa , 15°36'58.7"N 39°22'32.8"E, 74 m a.s.l., 4.-5.XI.2015, (Locality 15 EI,

Fig. 56), 7♂ 12♀ (holotype and paratypes, Figs. 27–44, 47–55), leg. F. Kovařík; Dese Island , 15°26'39.2"N 39° 45'32.7"E, 8 m a.s.l., 5.-7.XI.2015, (Locality 15 EJ, Fig. 59), 2♂ 8♀ 1juv. (paratypes, Figs. 57–58), leg. F. Kovařík; near Massawa, 15°36'55"N 39°24'22"E, 30 m a.s.l., 8.XI.2015, (Locality 15 EK) , 1♀ (paratype), leg. F. Kovařík; route Massawa to Gahtiela, 15°36'03.7"N 39° 16'38.4"E, 115 m a.s.l., 8.XI.2015, (Locality 15 EL, Fig. 60), 1♀ 1im., leg. F. Kovařík. All types are in the first author collection ( FKCP) .

ETYMOLOGY. Named after the country of occurrence.

DIAGNOSIS. Total length 26 (male) – 41 mm (female). Sexual dimorphism minor, adult males with chela of pedipalps broader and fingers of pedipalps slightly flexed proximally; there is no difference in length and width of metasomal segments. Base color uniformly yellow to yellowish brown with dark spot on fifth metasomal segment. Movable finger of pedipalp bears 10–11 rows of granules, all without external and with internal accessory granules ( acutecarinatus group of Levy & Amitati, 1980). Pedipalp chela length/width ratio 4.5 in males and 5.4 in females. Manus of chela shorter than fixed finger. Pedipalp chela length/movable finger length ratio 1.32–1.38 in both sexes. Trochanter of pedipalps with ten to twelve spiniform setae and two setae. Anterior margin of carapace bears 8 symmetrically distributed spiniform setae. First to third metasomal segments bear 10 carinae, fourth bears 8 or 10 carinae. All metasomal segments longer than wide. Pectinal teeth number 22–26 in males and 18–23 in females. Sternites and ventral surface of metasoma granulated, more so in males. Seventh sternite bears four crenulate carinae. Telson bulbous, aculeus shorter than vesicle. Subaculear tubercle present but not spinoid. Ratio of length vesicle/aculeus is 1.1–1.2.

DESCRIPTION. Total length 26–32 mm (male), 32–41 mm (female). The habitus is shown in Figs. 5–8. For position and distribution of trichobothria of pedipalps see Figs. 30–33 and 35. Sexual dimorphism minor, adult males with chela of pedipalps broader and fingers of pedipalps slightly flexed proximally ( Figs. 28 and 30); there is no difference in length and width of metasomal segments.

Coloration ( Figs. 57–58). The base color is uniformly yellow to yellowish brown, with dark spot on anterior half of the fifth metasomal segment; other spots missing or indicated only.

Carapace and mesosoma ( Figs. 9–12). The entire carapace is covered by granules of different sizes. The carinae are moderately to strongly developed and granular. The anterior margin of the carapace is almost straight, medially weakly concave, and bears eight symmetrically distributed spiniform setae. The tergites are granulated. Tergites I–VI bear very strong, denticulate lateral carinae. Each carina terminates in a spiniform process that extends well past the posterior margin of the tergite. Tergite VII is pentacarinate, with lateral pairs strong, serrato-crenulate and the median carina moderate, crenulate and present only in the proximal half. The pectinal tooth count is 22–26 (1x22, 9x23, 1x24, 2x25, 1x26) in males and 18–23 (1x18, 12x19, 15x20, 9x21, 1x22, 3x23) in females. The pectine marginal tips extend to half of the fourth sternite in the female and to onethird of the fifth sternite in the male. The pectines have three marginal lamellae and seven to eight middle lamellae. The lamellae bear numerous dark setae, each fulcrum with three or four dark setae. All sternites are finely granulated. The sixth and seventh segments bear four ventral crenulate carinae, which are more strongly developed on the seventh segment. The other sternites bear two cari-nae.

Metasoma and telson ( Figs. 39–44). The first to third segments bear 10 carinae, the fourth segment bears 8 or 10 carinae and the fifth segment bears five carinae. Intermediate carinae of the fourth segment are often replaced by isolated granules that may also form carinae. All segments are sparsely setose and densely granulated. Accessory rows of granules are present on dorsal surfaces of segments as well as on the ventral surface of the fifth segment. The telson is bulbous, with the aculeus a little shorter than the vesicle. The ratio of length vesicle/aculeus is 1.1–1.2. A subaculear tubercle is present and short.

Pedipalps ( Figs. 27–36). The pedipalps are granulated and hirsute. The femur bears five carinae. The patella bears seven granular carinae. The chela bears five carinae. The movable and fixed fingers bear 10–11 rows of granules, all without external and with internal granules. Pedipalp chela length/width ratio 4.5 in males, and 5.4 in females. Manus of chela shorter than fixed finger. Pedipalp chela length/movable finger length ratio 1.32–1.38 in both sexes. The trochanter of pedipalps bears ten to twelve spiniform setae and two setae.

Legs ( Figs. 37–38). Legs III and IV bear tibial spurs. Retrolateral and prolateral pedal spurs are present on all legs. The tarsomeres bear two rows of macrosetae on the ventral surface and several macrosetae on the other surfaces. Bristlecombs are absent. The femur bears four carinae and the patella bears four to six carinae. The femur and patella bear only solitary macrosetae and are granulated except for external lateral surfaces which are smooth.

Measurements. See Tab. 1.

Hemispermatophore ( Figs. 47–51). Flagelliform, elongate and slender, with trunk 4.8 times length of capsule region. Flagellum is well separated from the external lobe, unfolded, slightly longer than the trunk, the proximal 70% of its length with narrow lamina running along internal side of cylindrical core. Distal 30% of flagellum without lamina, narrower, coiled. Capsule region with 4 lobes at base of flagellum, conforming to 3 + 1 configuration prevalent in Buthus group (Kovařík et al., 2016) ( Fig. 47). External lobe longest, apically acuminate with symmetric vertex; median lobe shortest, apically truncate with acuminate internal vertex. Median lobe carina not well developed. Internal lobe acuminate with long thin vertex, slightly shorter than median lobe. Basal lobe strongly developed, broad, hamate, about same size as median lobe. External and basal lobes darker, more sclerotized than other lobes.

The shapes and relative dimensions of the capsule lobes are quite similar to those that have been described in other Compsobuthus species , including C. carmelitis Levy et al., 1973 , C. jordanensis Levy et al., 1973 , C. levyi Kovařík 2012 , C. nematodactylus Lowe, 2009 , C. polisi Lowe, 2001 , and C. werneri (Birula, 1908) ( Levy et al., 1973; Levy & Amitai, 1980; Lowe, 2001, 2009; Vachon, 1949, 1952). The Compsobuthus lobes differ significantly from the lobes of some other Buthus group genera. For example, the broad, robust basal lobe of Compsobuthus contrasts with the smaller basal lobes of Androctonus , Apistobuthus , Buthacus , Hottentotta , Leiurus , Odontobuthus and Vachoniolus (Levy & Amitai, 1980; Lowe, 2009 a, 2010a, 2010b, 2010c; Lowe et al., 2014; Vachon, 1949, 1952, 1958; Vachon & Stockmann, 1968). These consistent differences support the usefulness of hemispermatophore characters in the genus level taxonomy of buthids (Kovařík et al., 2016).

Karyotype ( Figs. 52–54). We analyzed one male paratype using standard cytogenetic methods (e. g. Kovařík et al., 2009). The diploid complement of this specimen is composed of 22 chromosomes ( Fig. 52). This diploid number has also been documented in one more species of this genus, C. matthiesseni (Birula, 1905) from Turkey (Šťáhlavský et al., 2014). The chromosomes of the analyzed C. eritreaensis sp. n. specimen gradually decrease in size from 6.70 % to 2.81 % of the diploid set. The chromosomes exhibit holocentric organization without localized centromere region and achiasmatic behavior during meiosis, these characters are typical for buthid scorpions (e. g. Mattos et al., 2013). Prominent constrictions are visible on one pair of large chromosomes during mitotic metaphase ( Fig. 52). These constrictions may correspond to the position of nucleolar organizing regions (NORs) as was documented also in Androctonus Ehrenberg, 1828 species ( Sadílek et al., 2015). Similar to this genus, the position of constriction is also approximately in one third of the chromosome in C. eritreaensis sp. n. During meiosis we found only bivalents in all observed pachytene ( Fig. 53) and all analyzed metaphases II exhibited the same number of chromosomes (n=11; Fig. 54).

AFFINITIES. The described features distinguish C. eritreaensis sp. n. from all other species of the genus. They are recounted in the key below. It differs from C. abyssinicus in having lighter colored tergites and metasoma, and longer pedipalp fingers mainly in male; and from C. somalilandus in the shape of the chela, and also in reduced or missing dark spots; shorter and non-spinoid subaculear tubercle; and longer aculeus of telson. A subaculear tubercle is present and variable in size in C. eritreaensis sp. n., but is never as long and spinoid as in C. somalilandus ( Figs. 13–14 versus Figs. 17–18). The aculeus of the telson is in C. eritreaensis sp. n. only a little shorter than the vesicle ( Figs. 13–14). The ratio of length vesicle/aculeus is 1.1–1.2 in C. eritreaensis sp. n., while in C. abyssinicus the ratio is 1.3–1.4 and in C. somalilandus is 1.55–1.6.

COMMENTS ON LOCALITIES AND LIFE STRATEGY. The first author visited the type locality 15EI ( Fig. 56) on 4 November 2015 and collected with UV light. C. eritreaensis sp. n. was commonly active immediately after sunset. At the locality, the first author recorded after sunset air temperature 31.5°C. In addition to C. eritreaensis sp. n., there was also recorded at this locality Neobuthus eritreaensis Lowe et Kovařík, 2016 (type locality). Between 5th and 7th November 2015 the first author visited the locality 15EJ ( Fig. 59) and collected two nights with UV light. C. eritreaensis sp. n. was commonly active immediately after sunset and was the most common scorpion species. At this locality, the first author recorded temperature 34.2 ºC– 28.8 ºC (minimum temperature at night) and humidity varied between 56% and 77%. In addition to C. eritreaensis sp. n. there was also recorded at this locality Microbuthus litoralis (Pavesi, 1885) and Pandinus magrettii Borelli, 1901 . On 8 November 2015 the first author stopped at the locality 15EK very near to 15EI and found another female paratype during the day under stones. In addition, there was recorded at this locality Neobuthus eritreaensis and Parabuthus abyssinicus Pocock, 1901 . On 8 November 2015 the first author stopped at the locality 15EL ( Fig. 60) very near to 15EI and 15EK localities and found two other paratype specimens during the day under stones, and in addition recorded at this locality Hemiscorpius sp.