Taxonomic notes , a new species , and a key to Indian species of the click beetle genus Cryptalaus Ȏhira , 1967 ( Coleoptera : Elateridae : Agrypninae )

Cryptalaus alveolatus sp. nov. is described and illustrated from India. The species has unique morphological characters: conspicuous longitudinal median ridge on pronotum, elytral interstria II more depressed than interstriae I and III. The Indian fauna of the genus Cryptalaus Ȏhira, 1967 is updated and represented by seven species: C. alveolatus sp. nov., C. assamensis (Schwarz, 1902) comb. nov., C. eryx (Candèze, 1874), C. lynceus (Candèze, 1874), C. nodulosus (Waterhouse, 1877) comb. nov., C. sculptus (Westwood, 1848) and C. sordidus (Westwood, 1848). Genitalia and terminalia of male and female C. sordidus are also illustrated. A key to the Indian species of Cryptalaus is given.


INTRODUCTION
Cryptalaus Ȏhira, 1967 was established as a subgenus of Alaus Eschscholtz, 1829 to include species with the presence of mesometaventral junction. Eventually, it was elevated to generic level and Paracalais Neboiss, 1967 was synonymized with it by Ȏhira (1990).  reported 15 species from the Palaearctic region, five of which, namely, C. cenchris (Candèze, 1857), C. eryx (Candèze, 1874), C. lynceus (Candèze, 1874), C. sculptus (Westwood, 1848) and C. sordidus (Westwood, 1848), were from the North Indian region. Only two, C. lynceus (Candèze, 1874) and C. sculptus (Westwood, 1848), are represented from India by the type locality. Chandra et al. (2018) catalogued two more species, C. berus (Candèze, 1865) and C. griseofasciatus (Schwarz, 1902), from the Indian Himalayan region. The present knowledge on Cryptalaus species from the Indian region is scarce because it is based mainly on the above recent checklist or catalogue. Therefore, this study aims to evaluate and validate the actual presence of Cryptalaus species from the Indian subcontinent, describe a new species, and provide an identification key to the Indian species of this genus.

MATERIALS AND METHODS
The study is based on the materials examined from the following collections: BNHS-Bombay Natural History Society, Mumbai, India FRI-Forest Research Institute, Dehradun, India ZKJSSC-Zoology Department, K.J. Somaiya College, Mumbai, India This study was carried out by examining the adult morphology of Cryptalaus species. The definition of Cryptalaus follows Ȏhira (1967,1990) and Johnson (2001). Morphological terminology used for the study follows Calder (1996), Casari (2008), and Costa et al. (2010). The limits of the Oriental and Australian regions are based on Johnson (2001).
Materials from BNHS and ZKJSSC were examined under a Dewinter Zoomstar II stereomicroscope, while materials from FRI were observed under an E. Leitz Wetzlar microscope. As there are very few specimens of C. assamensis, C. eryx, C. nodulosus, and C. sculptus representing Indian region, it was not possible to prepare genitalia for the examination. Photographs of the new species and C. sordidus were taken using Nikon D3200, Nikon D5300, and Nikon AF105 macro lens with Kenko extension tubes. Photographs of the type(s) and non-type specimens provided by various museums were also used in the study to confirm descriptions and keys from the original and subsequent publications as well as to correlate with the materials examined from the abovementioned collections.
Body length was measured from the anterior edge of frons to the apices of elytra. Body width was measured near half of its length, usually before the middle of elytra. Pronotum length was measured at midline and width at the half. The elytral length was measured from anterior margin of an elytron to its apex and width at the half. Aedeagus was measured along the midline from the apex of the median lobe to the apical margin of the basal piece. For genitalia preparation, the abdomen was severed from the body and kept overnight in cold 5% KOH for a male and 10% KOH for a female. The male and female genitalia and terminalia were then removed, washed with water followed by a short treatment in 90% alcohol. Terminalia and male genitalia were preserved in alcohol, while female genitalia were stored in glycerol.
Under each species taxon, we provide literature (citing Indian localities) with relevant information on the taxon, type locality, information on type material with its depository, Indian material examined, distribution within India, measurements (given in range), diagnostic characters and remarks, wherever applicable. Under the 'Distribution in India' section, actual localities of the specimens physically examined are provided and the localities given in the literature, for which specimens were not available, are mentioned in parenthesis. The data labels are quoted verbatim with a single slash (/) separating each data label under the specimen. Within the data label section, additional information and current geographic names are provided in square brackets.
Types of the newly designated species were marked with red labels denoting their type status (holotype or paratype), gender, name of the species, and the authors.
The acronyms used for museums with the type specimens are as follows: NHM
This species resembles C. lynceus (Candèze, 1874), which is known only from North India, in general appearance and characters: pronotum longer than wide, anterior edge of pronotum with two teeth-like projections, disc of pronotum with longitudinal median region raised. However, the new species differs from it by the following combination of characters: body pitchblack, anterior 1/3 of pronotum with yellow-brown scales, while posterior 2/3 with brown-black, large elytral patch of black pubescence around eight interstriae wide in its mid-length, sides of pronotum sinuous, pronotum with conspicuous longitudinal median ridge, elytral interstria II more depressed than interstriae I and III, elytral apices emarginate with prominent sutural and lateroapical spines.
Description: Holotype, female (ZKJS 10): Body elongate (Image 1) 26 mm long, 6.8 mm wide, pitchblack, with antennomeres I-III and maxillary palpi redbrown; dorsum densely covered with white, black to several tonalities of brown, decumbent scale-like setae; head, anterior 1/3 of pronotum with yellow-brown scales gradually fading to brown-black scales in posterior 2/3 of pronotum, with two pitch-black discal spots medially; elytral interstria I with alternate black, white to light brown bands, two white to light brown blotches in posterior half of elytra sandwiched between three black blotches covering interstriae around III-X; ventrally (Image 2) with sparse white setae medially, laterally more yellow-brown to black; abdominal ventrite V with transverse band of yellow-brown scales.
Head: Short (Image 4), slightly wider than long (length/width 0.76), including eyes 0.5 times as wide as pronotum; frons (Image 4) carinate over antennal insertion, with shallow triangular depression medially; punctures dense. Labrum transverse, narrow, around 6.5 times as wide as long, sparsely punctate, covered with yellow, long setae. Maxillary palpi with apical palpomere securiform. Antennae (Images 1, 4, 6) short, slightly reaching about half of pronotal length in dorsal view, serrate from antennomere IV. Length ratio of antennomeres II-IV is about 1.0 : 2.0 : 3.3. Antennomere II about 1.5 times as wide as long; antennomere III about 1.1 times as wide as long; antennomere IV about 1.1 times as long as wide; antennomere XI as long as antennomere IV, 1.4 times as long as wide.
Thorax: Pronotum (Image 5) 1.17 times longer than wide, and 1.24 times longer than wide including posterior angles. Anterior edge (Image 6) sinuous, raised medioanteriorly forming two teeth-like projections; anterior angles acute, slightly produced anteriad; sides sinuate, gradually narrowed anteriorly, and smoothly sloping towards posterior angles; posterior angles long, pointed, divergent, with carinae slightly reaching beyond base. Disc of pronotum (Images 5, 7) notably with raised longitudinal median ridge in its posterior 3/4 (visible in both dorsal and lateral view), with median basal tubercle slightly raised and rounded. Punctures dense, round to oval, shallow. Hypomeron (Image 8) with anterior angles acute; punctures dense, intervals between punctures on average smaller than diameter of one puncture. Prosternum (Images 7, 8) in front of procoxae about 4.9 times longer, 2.6 times wider at base of chin piece, 1.6 times wider before procoxae than diameter of procoxa; chin piece around 3.0 times wider than long with anterior edge arcuate, around 20 degrees below prosternal plane in lateral view; surface convex in ventral view, punctures less denser, slightly larger than on hypomeron, each puncture on average separated by about 0.5-1.0 times its diameter; prosternal process (Images 8, 9) about 3.0 times longer than diameter of procoxa, inclined considerably around 10 degrees behind procoxae in lateral view, underside with notable dent in middle. Mesoventrite (Image 2) 1.5 times wider than long. Metaventrite (Image 2) 1.34 times wider than long; metaventral discrimen (Image 21) touching anterior edge of metaventrite, deeply furrowed in about its posterior 1/3, almost touching posterior edge. Metacoxal plate about 5.2 times as wide as narrowest part, anterior edge oblique, posterior edge subparallel to anterior edge. Scutellar shield (Images 10-12) distinctly folded in two planes, anterior 2/3 in vertical plane, posterior 1/3 in horizontal plane; anterior edge slightly emarginate in middle; sides sloping in vertical plane, notably rounded near fold, again sloping in posterior plane; posterior edge with slight notch concealed under pubescence. Elytra (Images 11-13) almost twice as long as pronotum, 2.3 times as long as its combined width, together as wide as pronotum;  Male unknown. Etymology: The Latin word "alveolatus" means hollowed out like a trough. The specific epithet refers to depressed elytral interstria II (than interstriae I and III), which appears to be trough-shaped (see Image 12). (Schwarz, 1902) (Image 22) pitch-black with antennomeres I-III, trochanters redbrown; dorsum densely covered with grey to yellow decumbent scales intermingled with black spots; pronotum with two eye-like spots of black pubescence elongated oval, deviated towards central axis; elytral interstriae VII-VIII with elongate black patch near half of elytral length. Antennae short, slightly reaching half of pronotal length. Length ratio of antennomeres II-IV is about 1.0 : 1.6-2.0 : 3.0-3.6. Pronotum 1.18-1.19 times longer than wide and 1.28-1.30 times longer than wide including posterior angles, anterior edge with two teeth-like projections, anterior angles broad in dorsal view, sides narrowly convex to subparallel, posterior angles long, narrow, pointed and strongly divergent with carinae slightly reaching beyond base, disc with slightly raised median longitudinal surface glabrous, punctures denser laterally than on median longitudinal surface, with weakly developed transverse median carina near base. Scutellar shield almost as long as wide. Elytra 1.88-2.03 times as long as pronotum, 2.21-2.24 times as long as its combined width, apex emarginate with slightly produced sutural and lateroapical spine.

Cryptalaus assamensis
Male unknown. (  Diagnostic characters: Female: Body (Image 24) red-brown with pronotal longitudinal median region, hypomeron and prosternum, maxillary palpi pitchblack; dorsum densely covered with white to light brown decumbent scales intermingled with black spots and patches; pronotum with two eye-like spots of black pubescence oval; two interstriae wide semicircular ring-like black patch on elytral interstriae VII-IX at near half of elytral length, ring-like patch anteriorly never touching interstriae IX-X, posteriorly touching interstriae X rarely. Antennae short, slightly reaching half of pronotal length. Length ratio of antennomeres II-IV is about 1.0 : 1.6-2.3 : 2.0-2.6. Pronotum 1.12-1.18 times longer than wide and 1.21-1.28 times longer than wide including posterior angles, anterior edge with two teeth-like projections not raised, anterior angles acute in dorsal view, sides evenly convex and narrowly sinuous before posterior angles, posterior angles short, narrow, pointed and divergent with carinae just reaching beyond base, disc with longitudinal median carina obliterating in prominent transverse median carina near base. Scutellar shield 1.2-1.5 times as long as wide, subpentagonal. Elytra 1.90-2.35 times as long as pronotum, 2.10-2.35 times as long as its combined width, interstriae flat, apex narrowly emarginate with slightly produced sutural spine.

Cryptalaus eryx
Male similar to female in shape, size and appearance. Antennae reaching well beyond half of pronotal length, not reaching base of posterior angles. Length ratio of antennomeres II-IV is about 1.00 : 1.67-1.80 : 2.5-2.8. ( Diagnostic characters: Female: Body (Image 26) dark brown; dorsum densely covered with grey and dark brown decumbent scales mixed with black spots and patches; pronotum with two eye-like spots of dark pubescence large and rounded; elytral large patch of dark pubescence about five interstriae wide. Pronotum longer than wide, anterior edge with two teeth-like projections, sides evenly convex and narrowly sinuous before posterior angles, posterior angles short, narrow, pointed and divergent, disc with longitudinal median region raised. Scutellar shield oblong, uniformly declivous. Elytra less than twice as long as pronotum, apex rounded.

Cryptalaus lynceus
Male unknown. Remark: There is only one specimen of this species in NHM collection and is marked with label "Type". We have followed recommendation 73F, article 73.2 and 73.2.1 of ICZN for considering the specimen as "Syntype". Diagnostic characters: Female: Body (Image 28) pitch-black with antennae red-brown; dorsum densely covered with yellow-brown decumbent scales mixed with black spots forming patterns; pronotum with two eye-like spots of black pubescence small and oval; elytral interstria IV with elongate paler band near base with black spots on either end, elytral interstriae VI-X with black patch near half of elytral length partially encircling brown pubescence. Antennae short, slightly reaching half of pronotal length. Length ratio of antennomeres II-IV is about 1.0 : 1.8-2.0 : 2.8-3.0. Pronotum 1.15 times longer than wide and 1.24 times longer than wide including posterior angles, anterior edge with two teeth-like projections raised, pointed and strongly produced anteriorly, anterior angles conspicuously broad in dorsal view, sides almost subparallel, posterior angles short, pointed and slightly divergent with weak carinae not reaching near base, disc with uniformly and widely raised longitudinal median surface terminating posteriorly with prominent transverse median carina, punctures uniformly dense. Scutellar shield slightly longer than wide, subpentagonal. Elytra 2.19 times as long as pronotum, 2.40 times as long as its combined width, apex emarginate with strongly produced lateroapical spine.
Male unknown.

Remark:
The locality label is missing from the syntype specimen. It is determined to be "Andaman Is.
[sic]" from the original description. Waterhouse (1877: 4) mentioned both male and female, but did not mention actual number of specimens examined in the description. There is only one female syntype specimen in NHM collection (pers. comm. with Michael Geiser, NHM on 13.ix.2019). In the description, Waterhouse states "Elytris ad apicem emarginatis; abdominis segmento quinto apice truncate" for male and "Elytris ad apicem vix truncatis; abdominis segment quinto apice rotundato" for female. But it is found that female has the typical dimorphic characteristic of genus Cryptalaus: abdominal ventrite V truncate posteriorly with dense spatulate setae. (Westwood, 1848) (Images 30, 31) Alaus sculptus Westwood, 1848: 72 (original description, type locality: Kasyah Hills = linguistically J TT 2.5-2.7. Pronotum 0.98-1.10 times as long as wide and 1.02-1.16 times as long as wide including posterior angles, anterior edge with two teeth-like projections slightly produced, anterior angles conspicuously acute in dorsal view, sides strongly and evenly convex, posterior angles short, broad, pointed and moderately to strongly divergent with carinae just reaching base, disc with irregular wrinkly surface, median basal tubercle raised in transverse ridge and with small transverse tubercular ridge posteriorly near base just before median basal tubercle, punctures irregularly arranged. Prosternum with groove on prosternal process between procoxae extending anteriorly, not reaching half of prosternal length and posteriorly to about half of prosternal process, prosternal process curved distinctly in lateral view. Scutellar shield folded in two planes, anterior half folded in vertical plane and posterior half in horizontal plane. Elytra 1.80-2.07 times as long as pronotum, 1.83-2.02 times as long as its combined width, apex truncate with slightly produced sutural region without spine giving appearance as to be narrowly emarginate.

Cryptalaus sculptus
Male (Image 30) similar to female in shape and appearance. Antennae reaching well beyond half of pronotal length, not reaching base of posterior angles. Length ratio of antennomeres II-IV is about 1.00 : 1.8-2.2 : 2.5-2.8.
Remark: There is only one specimen of this species in OUMNH collection and is marked with label "TYPE". We have followed recommendation 73F, article 73.2 and 73.2.1 of ICZN for considering the specimen as "Syntype". ( Male similar to female in shape and appearance. Antennae reaching well beyond half of pronotal length, not reaching base of posterior angles. Length ratio of antennomeres II-IV is about 1.0 : 1.6-2.0 : 3.3-3.6.

Cryptalaus sordidus
Additional description: Hind wing-(Image 47, ZKJS 66A) 2.7 times as long as wide, apex slightly pointed; radial cell long, about five times as long as wide; r3 extending about 0.3 times as long as radial cell. Abdomen-Female (ZKJS 66A): Tergite VIII (Image 38) 1.17 times as wide as long; anterior edge strongly concave, sides anteriorly narrower than posterior end, posterior edge strongly arcuate, medially slightly emarginate; rows of short setae arising from mediolateral region to posterior edge, gradually with row of much longer setae on posterior edge; sparsely covered with punctures; colorless median area distinctly shaped with inner lateral margins wavy and posterior margin arcuate. Sternite VIII (Image 37) 1.34 times as wide as long; sclerotized area horseshoe shaped with anterior margin subtrapezoidal, posterior margin deeply incurved in middle; rows of numerous short to long setae on mediolateral edge; spiculum ventrale almost twice as long as sternite VIII, touching tip of sclerotized area. Male (ZKJS 67A): Tergite VIII (Image 43) U-shaped, about 1.22 times as wide as long, anterior edge concave; medially and apicolaterally punctate with bristle-like setae. Sternite VIII (Image 41) subtriangular, about 1.47 times as wide as long, colorless median area with sparse punctures, posterior margin with dense pubescence of varying length, apex widely rounded without any setae. Tergite IX and X (Image 44) connected with membrane; tergite IX twice as wide as long, anterior margin almost linear, slightly emarginate medially, sides curving towards apex, posterior margin deeply incurved forming wide inverted V; tergite X small, V-shaped. Sternite IX (Image 42) elongate, twice as long as wide, apically rounded with sparse pubescence in middle. Genitalia-Female (Image 39, ZKJS 66A): Ovipositor 0.70 times length of abdomen (measured medially); coxites (Image 40) finely punctured, covered with long, lightly sclerotized setae, apically covered with densely arranged shorter setae at the tip; paraprocts 6.3 times as long as coxites, 0.86 times length of ovipositor. Colleterial glands five times as long as wide. Bursa copulatrix twisted but not coiled, two spermathecae on anteriormost section lightly sclerotized; single extension of long, tubular sac-like structure arising sub-apically on bursa copulatrix. Male (Images 45, 46, ZKJS 67A): Aedeagus more than twice as long as wide; median lobe gradually narrowed towards apex, apex narrowly rounded; basal struts moderately short, about 0.33 times as long as aedeagus. Parameres abruptly constricted behind subapical hook with small setae near constriction; apical lobe of paramere with pointed apex, outer margin slightly rounded medially with more setae on dorsal side than on ventral, sinuate just before subapical hook; subapical hook sharp.
Remark: There are 25 specimens of C. sordidus from India in FRI collection [all with Acc. No. 4398]. Only six specimens spanning different Indian states have been studied and mentioned under 'Indian material examined' section. There is only one specimen of this species in OUMNH collection and is marked with label "TYPE". We have followed recommendation 73F, article 73.2 and 73.2.1 of ICZN for considering the specimen from OUMNH as "Syntype". The female syntype specimen (Image 32) has a remarkable deformity as stated by Westwood (1848: 72): "The specimen figured is a singular monstrosity; the middle leg on the right side having the coxa and trochanter of the normal form, followed by three femora conjoined together at the base, each with its perfect tibia, and with one imperfect and two perfect tarsi".

Ecology of Indian Cryptalaus species
Four Indian species are represented only from females: C. alveolatus, C. assamensis, C. lynceus, and C. nodulosus. Except for C. alveolatus all the above species are known from a limited number of specimens. Cryptalaus larvae are predaceous on immature woodboring longhorn beetles.  reports larvae of C. sculptus as predaceous on Sal tree, Shorea robusta, and cerambycid, Hoplocerambyx spinicornis (Newman). According to the data label under a specimen at FRI, (the larva of) C. sordidus is predaceous on Neoplocaederus obesus (Gahan) (= Plocaederus obesus). For brief insights on ecology of some Cryptalaus species and bionomics of C. sordidus see Beeson (1941: 297, 298). Besides C. sordidus, very little knowledge is available about the larval stages and biology of other Indian Cryptalaus species.

DISCUSSION
The species of the genus Cryptalaus Ȏhira are widespread in the Oriental and Australian regions. In India, however, the presence of the genus was mainly from the northern part. The recent checklists by  and Chandra et al. (2018) were the only source of knowledge for Indian Cryptalaus. A few species from these checklists such as Cryptalaus berus, C. cenchris, C. eryx, C. griseofasciatus, and C. sordidus were described originally from Japan, Oriental India (Eastern India; Laos, Myanmar), Laos, Borneo, and Sri Lanka, respectively. In this study, only the presence of C. eryx and C. sordidus from the Indian subcontinent is confirmed and a new species, inhabiting the Western Ghats and central India, is discovered. During the examination of Cryptalaus species, a single specimen each for species Alaus assamensis and Alaus nodulosus was discovered from the museum collection and transferred to Cryptalaus. This study confirms the following seven Cryptalaus species from India: C. alveolatus sp. nov., C. assamensis comb.
The present study also finds that the characters like the length ratio between antennomeres II-IV, anterior angles of pronotum and hypomeron vary significantly between the species. Thus, these characters, along with others, can be used for distinguishing the congeners. Future studies on Cryptalaus species based on ecological, molecular, and additional morphological data are essential to better our understanding of all congeners.