Lychas srilankensis Lourenço, 1997, Lourenco, 1997

Kovařík, František, Lowe, Graeme, Ranawana, Kithsiri B., Hoferek, David & Š, V. A., 2016, Scorpions of Sri Lanka (Scorpiones Buthidae, Chaerilidae, Scorpionidae) with description of four new species of the genera Charmus Karsch, 1879 and Reddyanus Vachon, 1972, stat n, Euscorpius 220, pp. 1-133: 48-56

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Lychas srilankensis Lourenço, 1997


Lychas srilankensis Lourenço, 1997  

( Figs. 13, 152–192, 198, 251, 407–408, 550)

Lychas srilankensis Lourenço, 1997: 831–836   , figs. 1–9; Lourenço & Huber, 1999: 26; Fet & Lowe, 2000: 168; Kovařík & Ojanguren, 2013: 209, 364, figs. 1462–1470.

= Lychas ceylonensis Lourenço & Huber, 1999: 23–26   , figs. 1–7 (syn. by Kovařík & Ojanguren, 2013: 209).

TYPE LOCALITY AND TYPE REPOSITORY. Sri Lanka, Northern Province, Mannar District, Occapu Kallu, Wilpattu   ; MHNG.

MATERIAL EXAMINED. Sri Lanka, Northern Province, Jaffna District , 09°42'51.6"N 080°04'44.8"E, 19 m a.s.l. (Locality 15CJ, Fig. 586), 26. –27.IV.2015, 1♂ after 5th ecdysis ( Figs. 152–153, 158, 160, 162–168, 174–180, 182, 198, 407) 1♀ ( Figs. 154–155, 159, 161, 169–173, 181, 408) 1im. ♂, FKCP, 1♂, UPSL, leg. Kovařík et al GoogleMaps   .; North Central Province, Puttalam District, Eluwankulam , 08°12'35.1"N 079°51'32"E, 52 m a.s.l. (Locality 15CN, Fig. 591), 28.IV.2015, 1♂ after 3rd ecdysis ( Figs. 183–186, 189, 550) 1♂ after 4th ecdysis 1♀ ( Figs. 191–192), FKCP, leg. Kovařík et al GoogleMaps   .; North Central Province, Puttalam District, Eluwankulam , 08°17'15"N 079°50'38.7"E, 38 m a.s.l. (Locality 15CO, Fig. 592), 28.IV.2015, 2♂ ( Figs. 156–157, 251) 1♀, FKCP, 1♀ 1juv, UPSL, leg. Kovařík et al GoogleMaps   .

DIAGNOSIS. Total length 38–65 mm. Sternum type 1, subpentagonal, exhibiting horizontal compression. Metasoma approximately the same length in both sexes, or male with slightly longer metasoma. Sixth row of granules on both movable and fixed fingers of pedipalps with out external and internal granules. First through third metasomal segments with 10 carinae, fourth with eight carinae. Lateral inframedian carinae of second and third metasomal segments may be incomplete. Fingers and manus of pedipalps identically colored, light and spotted. Manus of pedipalps smooth without granules in females and usually finely granulated in males. Pectinal teeth number 21–25.

HEMISPERMATOPHORE ( Figs. 183–186). Trunk broad, short, only slightly longer than capsule region. Capsule region broad. Flagellum short, laminiform, with broad hyaline fin along internal margin of cylindrical core. Median lobe broad, with thin dorsal carina near internal margin. Basal lobe strongly developed, a broad, blunt hook-like process arising dorsally at base of median lobe carina.

COMMENTS. The taxonomic position of this species is not clear. L. srilankensis   is very similar to L. tricarinatus (Simon, 1884)   and there is a real possibility that further study of L. tricarinatus   (type locality India, Pondichéry) could reveal that these two species are synonyms. Lourenço did not compare these two species and only compared L. srilankensis   with L. shoplandi (Oates, 1888)   and L. feae (Thorell, 1889)   (= L. shoplandi   ) from Myanmar in the original description ( Lourenço, 1997: 831–836, figs. 1–9). The description is superficial with several errors (e.g. compare Fig. 179 with fig. 6 in Lourenço 1997: 833, which depicts a spurious additional trichobothrium between d 4 and d 5; and the shape and densely hirsute setation of tarsomere II of leg IV in Fig. 165 with fig. 8 in Lourenço 1997: 833, which depicts same setation for tarsomeres I and II). Kovařík et Ojanguren (2013: 196) cited a difference in the length of the metasoma in males, but our study of new Sri Lankan specimens shows that there is little or no significant difference. Both species L. srilankensis   and L. tricarinatus   have the metasoma approximately the same length in both sexes, or the male has a slightly longer metasoma.

In the original description, L. ceylonensis   was characterized as having the terminal accessory granules on the movable finger of the pedipalp modified into another (seventh) row of granules (see fig. 7 in Lourenço & Huber, 1999: 24). The authors (p. 26) distinguished L. ceylonensis   from L. srilankensis   as follows: "... the presence of 7 oblique rows of granules on the movable finger of pedipalp, instead of 6 as in L. srilankensis   . The row of granules on the extremity of the finger is normal, and not represented merely by 3 or 4 accessory granules as it is in L. srilankensis   ". This is incorrect. The male holotype of L. ceylonensis   only has a right movable finger (the left is missing), and this finger only bears six rows of granules and three external accessory granules on its distal extremity (see Fig. 1465 in Kovařík & Ojanguren, 2013: 364), which is the normal condition for the genus Lychas   (see genus diagnosis), including L. srilankensis   .


Genus Reddyanus Vachon, 1972   stat. n. ( Figs. 14, 199, 201–220, 225–236, 245–250, 254–402, 409–420, 551–554, 561–570, Tables 3–5)

Isometrus (Reddyanus)   : Vachon, 1972: 176–177, figs. 14, 16, 18, 20; Vachon, 1982: 90–101, 108–110, figs. 47–67, 88–91; Fet & Lowe, 2000: 150–154; Kovařík, 2003: 5–14, figs. 1–8; Kovařík & Ojanguren, 2013: 184–193, 347–354, 357–360, figs. 1265–1367, 1384–1409.

Isometrus   ( Raddyanus   [sic]): Tikader & Bastawade, 1983: 254–311 (in part), figs. 727–770, 841–895.

TYPE SPECIES. Isometrus acanthurus Pocock, 1899   .

DIAGNOSIS. Medium sized buthids, adults 19–75 mm. Sternum type 1, triangular in shape. Pedipalps orthobothriotaxic, type Aβ. Chelal trichobothrium db located between et and est. Three to five pairs of lateral eyes. Tibial spurs absent on all legs. Pedipalp movable finger with six rows of granules, several accessory granules and external and internal accessory granules. Pedipalp fixed finger with seven rows of granules and six external and seven internal accessory granules. Cheliceral fixed finger with a single ventral denticle. Third and fourth legs with tibial spurs. Tibia and tarsomeres of legs I–III with setae not arranged into bristle combs on dorsal surfaces. Tarsomere II of leg IV with two sparse rows of <20 spiniform setae on ventral surface. Mesosoma dorsally with one median carina. Telson with subaculear tooth pointed or more often rounded. Males of most species have longer metasomal segments and often also a wider pedipalp chela manus than females.

SUBORDINATE TAXA. Currently, 27 species are formally included under the genus (cf. Kovařík & Ojanguren (2013) for information about species not treated here): Reddyanus acanthurus (Pocock, 1899)   comb. n., Reddyanus assamensis (Oates, 1888)   comb. n., Reddyanus basilicus ( Karsch, 1879)   comb. n., Reddyanus besucheti (Vachon, 1982)   comb. n., Reddyanus bilyi ( Kovařík, 2003)   comb. n., Reddyanus brachycentrus (Pocock, 1899)   comb. n., Reddyanus ceylonensis Kovařík, Lowe, Ranawana, Hoferek, Jayarathne, Plíšková et Šťáhlavský   , sp. n., Reddyanus corbeti (Tikader et Bastawade, 1983)   comb. n., Reddyanus deharvengi (Lourenço et Duhem, 2010)   comb. n., Reddyanus feti (Kovařík, 2013)   comb. n., Reddyanus heimi (Vachon, 1976)   comb. n., Reddyanus jayarathnei Kovařík   , sp. n., Reddyanus jendeki (Kovařík, 2013)   comb. n., Reddyanus khammamensis ( Kovařík, 2003)   comb. n., Reddyanus krasenskyi ( Kovařík, 1998)   comb. n., Reddyanus kurkai ( Kovařík, 1997)   comb. n., Reddyanus loebli (Vachon, 1982)   comb. n., Reddyanus melanodactylus (L. Koch, 1867)   comb. n., Reddyanus navaiae ( Kovařík, 1998)   comb. n., Reddyanus neradi (Kovařík, 2013)   comb. n., Reddyanus petrzelkai ( Kovařík, 2003)   comb. n., Reddyanus problematicus ( Kovařík, 2003)   comb. n., Reddyanus ranawanai Kovařík   , sp. n., Reddyanus rigidulus (Pocock, 1897)   comb. n., Reddyanus tibetanus (Lourenço et Zhu, 2008)   comb. n., Reddyanus vittatus (Pocock, 1900)   comb. n. and Reddyanus zideki ( Kovařík, 1994)   comb. n..

COMMENTS. Vachon (1972: 177) described the subgenus Reddyanus   and distinguished it from the nominotypic subgenus Isometrus Ehrenberg, 1828   by the position of chelal fixed finger trichobothria (trichobothrium db located between dt and et in Isometrus   , between et and est in Reddyanus   ). Vachon also cited the different positions of the e 2 trichobothria on the femur (see figs 15, 16 in Vachon, 1972: 176). Subsequently, Vachon (1982) add- ed another character for distinguishing the two subgenera: Isometrus   has pedipalp fixed fingers with six rows of granules and six external and internal accessory granules ( Figs. 252–253 and figs. 64, 65 in Vachon, 1982: 100), and Reddyanus   has pedipalp fixed fingers with seven rows of granules and six external and seven internal granules ( Figs. 254–259 and figs. 66 and 67 in Vachon, 1982: 100). Here we propose two additional characters for distinguishing these taxa: (i) ventral aspect of tarsomere II of leg IV with two dense rows of> 30 longer, more filamentous setae in Isometrus   ( Figs. 196– 197), vs. two sparse rows of <20 shorter, thicker, more spiniform setae in Reddyanus   ( Figs. 199, 205–208); (ii) hemispermatophore with a relatively short, broad trunk, a short, broad, uncoiled flagellum, and a smaller, blunt basal lobe in Isometrus   ( Figs. 146–149), vs. a narrow trunk, a long, thin, coiled flagellum and a much enlarged, pointed basal lobe in Reddyanus   ( Figs. 283– 286). The form of the hemispermatophore of Isometrus   appears more similar to that of Lychas   ( Figs. 183–186), than to Reddyanus   . Differences in trichobothriotaxy, pedipalp finger dentition, tarsal setation and hemispermatophore structure provide characters that are useful for higher level classification of buthid scorpions (Kovařík, 2009; Lamoral, 1979; Sissom, 1990; Stahnke, 1972; Stockwell, 198; Vachon, 1952). Taken together, these differences support our taxonomic decision to elevate Reddyanus   to a genus distinct from Isometrus   .

DISTRIBUTION. Oriental region from India, China (Tibet) to Melanesia.


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Lychas srilankensis Lourenço, 1997

Kovařík, František, Lowe, Graeme, Ranawana, Kithsiri B., Hoferek, David & Š, V. A. 2016

Lychas srilankensis Lourenço, 1997: 831–836

LOURENCO 1997: 836