Cephalaeschna patrai Dawn 2021, sp. nov.
Creators: name: Dawn, Prosenjit
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Odonata
Aeshnidae
Cephalaeschna
Cephalaeschna patrai

description: Cephalaeschna patrai sp. nov.
Holotype: Male (Fig. 1F), near the trail from Thulo Dhunga River to Aloobari forest camp, Neora Valley National Park, Darjeeling district, West Bengal, India (27.1195°N, 88.7173°E, alt. 2,306 m a.s.l.), collected when passing by in flight, 6.x.2018, Prosenjit Dawn leg.
Paratype (allotype): 1 female (Fig. 3C), small valley near the way from Chowdaphery Forest Camp to Lava (27.0851°N, 88.6996°E, alt. 2,324 m a.s.l.), collected when patrolling in flight, 10.x.2018, Prosenjit Dawn leg.
Etymology: The specific name ‘patrai’ is coined to honour Mr. Shubhankar Patra, a very dedicated naturalist of West Bengal, associated with documentation of floral and faunal resources for more than 30 years and inspiring many people including the author in nature study and conservation since more than two decades.
Description: Dark brown to black dragonfly marked with light apple green and yellow.
Head. Compound eyes blue, brownish near the junction of each. Posterior margin of the eye bright yellow (Fig. 1C). Face green and yellow shaded with light brown (Fig. 1A). Face roundish in shape, width more than ½ of the width of head including compound eyes (Fig. 3A). Labrum greenish yellow with black band at the edge, labium entirely black (Fig. 1B). Anteclypeus light brown with yellowish shade towards base. Postclypeus yellow at sides, greenish yellow in the middle and light brownish toward the base. Dorsal side of frons light brown, slightly elevated at crest with a blunt tubercular appearance in the middle in the anterior view. Anterior frons light brown with a palest greenish yellow tinge, laterally yellow margin continues from the postclypeus. Whole face covered with prominent long hairs all around and in the middle of the postclypeus.
Thorax. Prothorax light brown in the middle and yellow at sides. Pterothorax dark brown to black marked with apple green to yellow. Antehumeral stripe apple green, gradually tapering anteriorly. Two spindle shaped spots near the antealar ridge. Dorsal carina as prominent ridge with a pointed projection. Dorsal markings of the thorax shown in Fig. 1D. Two lateral stripes broad and apple green, becoming yellow ventrally; the anterolateral (humeral) stripe broken into two spots, the lower one of which is bigger, connected with the upper with a fine line (Fig. 1E). A small triangular green spot present near the subalar ridge, under a quadrangular spot at forewing base. A small oval shaped yellowish green spot beneath metastigma. Metepimeron with a broad triangular band mostly yellow, separated by a fine line from a green spot at hindwing base. Legs dark brown to black, except for proximal half of all femora brown.
Wings hyaline with very light brown tint overall and little darker at the tip. Discoidal cell in forewing three celled (both right and left), 5-celled in right hindwing and 4-celled in left hindwing. Anal membrane white and rudimentary; six cells in anal triangle and eight cells in anal loop for both right and left hindwing. Pterostigma covering 2–3 cells, black in color. Arc in forewing is at the level of distal primary antenodal nervure (Fig. 1G & 2E). Nodal index: 19 antenodals and 17 postnodals in left forewing and 20 antenodals and 14 postnodals in right forewing; 15 antenodals and 17 postnodals in both hindwings. Median space of all wings with four crossveins except the left hindwing having three.
Abdomen. Dark brown to black abdomen marked with light green and yellow (Fig. 1F & 1H). S1 with a dorsal narrow sky-blue to greenish band and a quadrangular greenish patch on each side; S2 with a dorsal narrow bluish green band broken in the middle, a pair of narrow dorsolateral triangular marks in the same level of oreillets, which are bright yellow with black posterior margin. The dorsal longitudinal band extended to become narrow green line at the distal border of the segment. S3 to S7 marked dorsally with green in more or less similar manner as follows: dorsal carina with a fine green line interrupted in the middle of the segment and posteriorly connected with a ring near posterior end of each tergum; a pair of elongated triangular middorsal thin marks separated by the carina in the middle. S3–S9 with lateral yellow spot at anterior end of each segment, that of S3 is triangular, S4–S7 elongated oval in shape and reducing to small round spots on S8 and S9 (Fig. 1F & 2B). S8 and S9 with a pair of dorso-lateral oval greenish yellow spots at the distal end and only fine remnants of yellowish line in the anterior end. S10 with two round yellow spots at the posterior border adjacent to the base of the anal appendages and brownish yellow remnant spot at the antero-lateral margin (Fig. 2A).
Anal appendages completely black, cerci slightly longer than dorsal length of S10 (Fig. 2A), spatulate in dorsal view (Fig. 2A), blunt rounded end distinctly curved upward to form a prominent tubercle which merges with continuation of the distinct median ridge. The blunt tubercles turn inward in dorsal view (Fig. 3B). From lateral view the cerci appear to gradually broaden towards tip and ends with the upcurving (Fig. 2B & 3C). Paraprocts almost 2/ 3 in length of the cerci, gradually upcurved, slightly bifurcated at the extreme tip and have two small blunt spines at apex. Cerci with many long fine hairs at the inner margin and small setae at the outer edges.
Secondary genitalia. Base of the penis dark brown, glans creamy white with a pair of commas shaped brown spots. Tip of the glans again darkened in dorsal view. Two almost transparent filaments of just double the length of glans gradually diverges towards the tip of the glans (Fig. 2C & 2D).
Measurements: Abdomen length (including anal appendages): 46 mm, Hind wing length: 38 mm.
Description of female. Body color more brownish than male (Fig. 4C). Similar facial and thoracic markings (Fig. 4A, B & D) with male’s, but most of black color parts in male are replaced by dark to light brown in female. Anterolateral stripe broken into two different patches, connected with the finest line. Rest of thoracic color patterns very similar to the male (Fig. 4D). Wings more tinted with light brown (Fig. 4E). Pterostigma dark brown. Triangle 5-celled in forewing, 4-celled in hindwing; anal loop 9-celled in both hind wings. Discoidal cell 5-celled in forewing and hindwing 4-celled. Median space with five cross-veins in right wings and four in left wings. Nodal index: 22 antenodals and 16 postnodals in left forewing and 20 antenodals and 17 postnodals in right forewing; 17 antenodals and 17 postnodals in left hindwing and 15 antenodals and 16 postnodals in right hindwing. Abdominal markings similar to those of the male but much inconspicuous. Dorsal markings on abdomen obscure but S3–S7 each with prominent oval shaped bright yellow spots laterally near the anterior border of the segment. Yellow antero-lateral spot on S8 restricted to a small round spot and lost on S9 and S10. No dentigerous plate on S10. Cerci just equal to the length of dorsal length of S10. The ovipositor as long as just reaching the level of lateral valves (Fig. 4F). Anal appendage black, S9 and S10, ovipositor brown and tip of the valve yellowish.
Measurements: Abdomen length (including anal appendages): 44.3 mm, Hind wing length: 39 mm.
Diagnosis: Cephalaeschna patrai appears to be allied to three Indian species: C. orbifrons, C. viridifrons and C. klapperichi in many morphological aspects. Cephalaeschna orbifrons is known to have more inflated frons and green eyes (Asahina 1981a) whereas C. patrai have comparatively less inflated frons and blue eyes lined with yellow. The shape of the cerci of this species separates it from C. orbifrons and C. viridifrons, the cerci of the C. orbifrons are not prominently broad towards tip and in C. viridifrons it is not completely rounded at tip (Asahina 1981a, b). In addition to the abdominal coloration the current species differs from C. klapperichi by having six cells in anal triangle and eight cells in anal loop, whereas both are five cells in C. klapperichi (Asahina 1981a, 1983). Among the species known from Vietnam, C. aritai Karube, 2003 shows most similarity with the new species with similar facial coloration, discontinuous anterolateral mesothoracic stripe broken into two separate patches, tip of the cerci prominently curved upwards and similar penile structure (Karube 2003); in contrast C. aritai has a constriction in cerci at 1/3 rd distance from base when seen laterally. Additional characters of C. aritai that contradict with C. patrai are the antehumaral stripes gently curved outwards, pterostigma brown instead of black; abdominal maculation different without prominent dorsal midline and comparatively shorter female cerci (Karube 2003). The ventral view of the secondary genitalia in situ associated with the abdominal tergites of S1 and S2 of C. patrai appears very similar to that of C. orbifrons, while the penis ex situ has close similarity with that of Gynacanthaeschna sikkima (Karsch, 1891) in the lateral view (Asahina 1983); though C. patrai is distinguishable by the shape of the cerci from the former species and by presence of 5 celled anal triangle from the later species. In brief, Cephalaeschna patrai is distinguishable from other species for its distinctive shape of the cerci; these appears to be uniformly broad towards end, without any constriction when viewed laterally (Fig 3C). Tip of the cerci are prominently upcurved to form blunt tubercle which appears to be bending inwards in the dorsal view (Fig 3B). Other distinctive features are the anterolateral thoracic stripe being broken into two separate patches, connected with a narrow line and S9 with two oval and S10 with two round yellowish spots on postero-dorsal margin.
description: Published as part of Dawn, Prosenjit, 2021, A new species of Cephalaeschna Selys, 1883 (Odonata: Anisoptera: Aeshnidae) from Neora Valley National Park, West Bengal, India, with notes on C. acanthifrons Joshi & Kunte, 2017 and C. viridifrons (Fraser, 1922), pp. 371-380 in Zootaxa 4949 (2) on pages 372-375, DOI: 10.11646/zootaxa.4949.2.10, http://zenodo.org/record/4636199