Prosopistoma coorgum Balachandran and Anbalagan

Balachandran, Chellapandian, Anbalagan, Sankarappan, Kannan, Mani, Dinakaran, Sundaram & Krishnan, Muthukalingan, 2016, A new species of Prosopistoma Latreille, 1833 (Ephemeroptera: Prosopistomatidae) from South India, Zootaxa 4178 (2), pp. 289-294 : 290-294

publication ID	https://doi.org/ 10.11646/zootaxa.4178.2.7
publication LSID	lsid:zoobank.org:pub:3DDDC24E-8312-4304-9230-1DE4A2E96195
DOI	https://doi.org/10.5281/zenodo.6074308
persistent identifier	https://treatment.plazi.org/id/3701896C-8B02-FFD3-FF6F-FB7C0CD9FE71
treatment provided by	Plazi
scientific name	Prosopistoma coorgum Balachandran and Anbalagan
status	sp. nov.

Treatment

Prosopistoma coorgum Balachandran and Anbalagan , new species

( Figs. 2–4 View FIGURE 2 View FIGURE 3 View FIGURE 4 )

Type series. Holotype (deposited in ethanol): 1 mature nymph, INDIA, Kaveri River, Kushalnagar , Coorg district , Karnataka state, 18-I- 2015, 829 m (12º44′.80″ N, 75º96′.97″E), collected by S. Anbalagan & C. Balachandran . Paratypes (deposited in ethanol): 1 mature nymph on slide and 8 mature nymphs, same data as holotype; 4 nymphs, India, Kaveri River, Madikeri, Coorg district , Karnataka state, 19-I-2015, 1020 m (12º42′N, 75º73′E) (Coll. S. Anbalagan & C. Balachandran, Department of Environmental Biotechnology, Bharathidasan University, Catalogue number: PS012). GoogleMaps

Description. Mature Nymph ( Fig. 2 View FIGURE 2 ). Body length 3.4–3.8 mm, excluding caudal filaments. Head yellow dorsally with a U-shape brown marking encompassing median ocellus. Epicranial sutures evident, passing through anterior margin of lateral ocelli, and between compound eyes and antennal bases, continuing to lateral margin of head. Carapace ( Figs. 2 View FIGURE 2 A, 2C) general coloration medium brown, light yellowish brown around edges of carapace along flange, width 1.1 times longer than length measured along median suture; four distinctive orange markings present on each side of the midline: one on lateral region and three close to the mid line; proportional lengths of anterior, middle and posterior markings 1.00:.0.44:0.16. Cuticle of carapace finely punctuated. Distal end of carapace concave over exhalent notch ( Figs. 2 View FIGURE 2 A, 2C).

Head. Width 4.5 times longer than length. Antennae ( Fig. 3 View FIGURE 3 A) composed of 6 segments, slightly longer than distance from antennal base to anterior margin of head; segment (scape) usually retracts into head capsule, making it invisible; segment III the longest, about 2.4–3.2 times the combined length of segments IV–VI. Labrum ( Fig. 3 View FIGURE 3 B) protrudes apicomedially with surface punctated, approximately 2.9 times wider at its midpoint than long, anterior margin fringed with dense fine setae. Left and right mandibles similar. Outer canine of mandibles ( Fig. 3 View FIGURE 3 C) slightly longer than inner canine with three apical teeth, outer tooth small and outer margin serrated near apex with 2–3 small short spines, inner tooth larger with margin serrated near apex with 3 small spines; inner canine ( Fig. 3 View FIGURE 3 D) with two apical teeth, inner tooth a little larger, outer margin smooth; inner margin serrated near apex with 2–3 spines; two long serrated bristles arising from base of inner canine; a single stout seta present lateromedially on each mandible. Maxillae ( Fig. 3 View FIGURE 3 E) crowned by rigid canine and three subequal dentisetae; three long feathered setae with stout bristles arising from base of apical canine and dentisetae on galea-lacinia. A single unserrated bristle arising about two-thirds of way down the sclerotized section of galea-lacinia. Maxillary palpi ( Fig. 3 View FIGURE 3 E) 3- segmented, segments II the longest, length ratio of maxillary palp segments from basal one to apical: 3.3:4.8:1. Labium composed of pre and postmentum ( Fig. 3 View FIGURE 3 F & G); prementum trapezoid, cutting edge with fine teeth; scalelike structures present along basal margin of postmentum. Labial palpi ( Fig. 3 View FIGURE 3 F) 3-segmented, length ratio of labial palpus segments from basal one to apical 2:2.5:1.

Legs ( Figs. 4 View FIGURE 4 A). Dorsal margin of fore femur with 8–10 simple, short setae; ventral margin of fore tibia with 6–8 pectinate setae ( Fig. 4 View FIGURE 4 A). Mid and hind tibia each with one pair of stout distal setae, one pectinate seta, and a smooth seta ( Fig. 4 View FIGURE 4 B). Ventral and basal half surface of all femora with dense scale-like structures ( Fig. 4 View FIGURE 4 A); mid and hind femora with scale-like covering along the dorsal and ventral surface. All claws slender and smooth without denticles.

Abdomen. Abdominal gills as in figures 4C–F. Gill I with long lamellate with bifurcate upper portion, lower portion divided into ribbons, many of which branch dichotomously ( Fig. 4 View FIGURE 4 C); gill II leaf-like and cleft ( Fig. 4 View FIGURE 4 D), covering the gills III–V ( Figs. 4 View FIGURE 4 E & F), gill VI tiny, unbranched. Posterolateral projections of abdominal segments VII–IX broad, apex pointed ( Fig. 2 View FIGURE 2 A). The three caudal filaments are short and retractile as in all Prosopistomatidae .

Imago. Unknown.

Etymology. The species is named after the place of collection, Coorg.

Habitat. P. coorgum sp. n. nymphs were associated with boulders and pebbles, and they coexist with nymphs of Choroterpes Eaton, 1881 , Thalerosphyrus Eaton, 1881 and Platybaetis Muller-Liebenau, 1980 .