Cloeodes nigrohumeris, Kluge, 2017

Kluge, Nikita J., 2017, Contribution to the knowledge of Cloeodes Traver 1938 (Ephemeroptera, Baetidae), Zootaxa 4319 (1), pp. 91-127 : 114-121

Cloeodes nigrohumeris sp. n.

( Figs 92–125 )

“Genus nr. Neocloeon ”: Roback 1966: 133, Pl. 3: Figs 37–40 (larva).

Etymology. The adjective nigrohumeris refers to pair of black lines on anterolateral parts of imaginal mesonotum (“shoulders”).

Material examined. Holotype: L-S-I ♂ {specimen [XIX](3)2013}, PERU, Region Loreto, Provincia Ucayali, Pampa Hermosa, Quebrada Huanganaico , 7°12'S, 75°22'W, 18.VIII.2013, coll. N. Kluge & L. Sheyko . Paratypes: the same locality and collectors, 18–20.VIII.2013: 5 L-S-I ♂, 1 L-S ♂, 9 L-S-I ♀, 3 L-S ♀, 3 L/S ♂, 2 L/S ♀, 1 larva. Provincia Ucayali, 17 km NNE Contamana, Aguas Termales , 7°11'S, 74°57'W, 26.VII–4.VIII.2013, coll. N. Kluge & L. Sheyko: 3 L-S-I ♂, 1 L-S/I ♂, 2 L-S-I ♀, 1 L-S ♀, 3 L/S ♂, 1 L/S ♀, 7 larvae . Provincia Maynas, Quebrada El Sabalo (right tributary of Rio Itaya ) between Puente Itaya (57 km from Iquitos ) and San Joaquin (at Rio Amazon ), 4°16'S, 73°27'W, 1–16.II.2006, coll. N. Kluge: 1 L-S-I ♂, 7 L/S ♂, 5 L/S ♀, 33 larvae .

Descriptions. Larva. CUTICULAR COLORATION: Cuticle partly colorless, partly light brownish. Most part of head colorless. Pronotum and/or mesonotum either with colorless, light brownish and darker brow areas ( Figs 94 , 103 ), or at most part colorless with few small brown markings. Mesothorax and metathorax with contrasting brown macula adjacent to dorsal coxal articulation; in some individuals this macula occupies most part of episternum on metathorax and smaller part of episternum on mesothorax; remainder cuticle of thoracic pleura and sterna colorless ( Fig. 102 ). Legs light with or without diffusive darker macula at middle of femur, knee articulation, tibia just distad of patella-tibial suture and/or base of tarsus ( Fig. 102 ). Abdominal terga at most light, with few contrasting brown maculae ( Figs 96 , 100–101 ): tergum I at most brown; tergum II with anterior-median part and pair of submedian myo-sigilla brown; terga III–V at most colorless, tergum VI at most brown, tergum VII with unpaired medio-anterior brown macula, tergum VIII colorless, tergum IX often with lateral parts brown, tergum X light with brownish maculae. Abdominal sterna and paraprocts at most colorless. Caudalii light, often with brown band near apex ( Fig. 92–93 , 100–101 ).

HYPODERMAL COLORATION: Abdominal terga of mature and immature larvae of both sexes with contrasting reddish or brown maculae well visible through cuticle: terga II–VII with median macula and pair of transverse stripes on posterior margin; terga II, V and VI, beside this, with pair of lateral maculae (as in imago) ( Figs 92, 93, 95 ).

SHAPE AND SETATION: Frontal suture pointed, rectangular; face relatively long; in female larva eyes brought together (as in Fig. 6 ). Labrum equally wide at base and at middle, with pair of submedian long setae and one pair of sublateral long setae ( Fig. 106 ). Prostheca of left mandible with 3 blunt processes and 3 pointed processes; median margin of left mandible proximad of prostheca straight or slightly convex, smooth ( Fig. 104 ). Prostheca of right mandible directed medially-proximally, bifurcate, with longest branch directed proximally; median margin of right mandible proximad of prostheca convex or nearly straight, smooth or with serration, without seta-like processes ( Fig. 105 ). Stipes of maxilla proximally with 4–5 setae on ventro-medial side. Maxillary canines and distal dentiseta similar, all hooked medially ( Fig. 109 ). Maxillary palp 2-segmented, either reaching apex of lacinia, or slightly shorter, or slightly longer ( Roback 1966: Fig. 38 ). Labium with glossae and paraglossae subequal, both narrowed apically ( Fig. 108 ). Glossa dorsally with 1–2 stout pointed setae near apex and with 10–12 setae in dorso-lateral row; ventrally with irregularly arranged setae in proximal part and 5–7 setae forming ventro-median row. Paraglossa with latero-apical setae forming one regular row and few (2–4) setae just dorsad of it; with 4–5 setae in ventro-median row; with 4 setae in dorso-median row. Distal segment of labial palp widened apically, with median margin slightly shorter than lateral margin ( Fig. 108 ; Roback 1966: Fig. 40 ).

All thoracic terga without protuberances. Metanotum without vestiges of hind protoptera ( Fig. 102 ). Fore legs largest, middle legs smaller and hind legs smallest; on fore leg tarsus much longer than tibia, on middle and hind legs tarsus subequal to tibia; claws elongated, much longer than half of tarsal length ( Table 5; Fig. 102 ). Femur parallel-sided, with outer margin straight and inner margin slightly convex; apical projection equally short on femora of all leg pairs. Outer side of femur with 5–7 minute stout setae; apical projection with 2 larger spatulate setae. Inner and dorsal side of femur with few stout setae, which are subequal or smaller than setae on dorsal side. Patella-tibial suture and proximal arc of long setae with contiguous sockets equally developed on tibiae of all leg pairs; inner margin of tibia with irregular small stout pointed setae, apically with 2 larger setae (as in Fig. 16 ). Outer-apical seta blunt, reaching apex of tibia. Dorsal side of each tarsus in proximal half with long fine setae forming 2 longitudinal rows. Claw longer than 1/2 of tarsus length ( Fig. 102 ). Scales on abdominal terga and sterna numerous, short, triangular or semicircular, colorless and delicate ( Fig. 97 ).

Posterior margin of abdominal tergum I either entirely smooth, or with few irregular short denticles; posterior margins of terga II–X with regular long pointed denticles; on tergum IX, portion of posterior margin behind pair of submedian setae not markedly projected backward, either with diminished denticles ( Fig. 97 ), or without denticles. Posterior margins of abdominal sterna I–IV smooth or with minute denticles on sternum IV; posterior margins of sterna V–VIII with regular pointed denticles, shorter and lighter than denticles on terga. Each sternum II–VI with pair of regular transverse arched rows of long, fine, simple (not furcate) setae with closely contiguous sockets (as in Fig. 20 ). Tergalii I–VII long, lanceolate and pointed ( Figs 119–125 ). All tergalii with ribs only on proximal parts of costal and anal margins, without middle rib. Margins bearing costal and anal ribs smooth (not serrated); margin free of ribs slightly notched, with small seta in each notch. Paraprocts with anterior median apodeme poorly developed; each paraproct with unequal pointed denticles on posterior margin, with dense scales as on sterna and terga ( Fig. 107 ). Each swimming seta of caudalii divided into dark proximal part and colorless delicate distal part ( Fig. 101 ). Ventral and dorsal side of paracercus and lateral sides of cerci in middle part with one or several long pointed denticles on each 2nd segment.

DEVELOPING MALE GENITALS: In last larval instar, developing subimaginal gonostyli folded under larval cuticle in « Nigrobaetis -type» pose, with 2nd segment bent by convexity medially, and 3rd segment directed caudally ( Fig. 116 ).

RESPIRATORY MOVEMENTS: Larva is able to make respiratory vibrations by tergalii.

Subimago. CUTICULAR COLORATION: Cuticle with light brown and colorless areas. Head colorless, only antennae slightly tinged with pale brownish. Pronotum with light brown and colorless areas. Mesonotum at most light brownish, medioparapsidal suture colorless, other sutures darkened ( Fig. 98 ). Thoracic pleura with light brown and colorless areas; lateropostnotal crest narrowly colored by dark brown, diffusively bordered by light brown ( Fig. 99 ). Base of wing light brown, other wing cuticle lighter. Legs at most colorless; distal margin of each tarsal segment narrowly bordered by brown. Abdominal terga and sterna slightly colored with light brownish, microtrichiae brown. Cerci colorless.

HYPODERMAL COLORATION: As in imago.

TEXTURE: On all legs of both sexes last tarsal segment entirely covered by pointed microlepides; other tarsal segments at most part covered by blunt microlepides, apically by pointed microlepides ( Table 1).

Tarsal spines of subimago and imago. Tarsus of fore leg in male and female without apical spines. Tarsus of middle and hind leg of both sexes with 1 apical spine on initial 3rd tarsomere (next after 1st+2nd tarsomere) ( Table 1).

Imago, male. COLORATION ( Figs 110–113 ). Head ocher. Turbinate eyes either unicolor dull-orange or ocher-yellowish, or with proximal half darker and distal half lighter. Thorax ocher; mesonotum with pair of anterolateral contrasting dark brown or black stripes bordering mesonotum anteriad of wing bases and including antelateroparapsidal scutal sutures. Wing membrane colorless; veins at most ocher or light brownish, basal parts of veins C, Sc, MA, MP and CuA darkened with brown. Femora of all legs ocher, with brown or reddish subapical band (hypodermal coloration); fore femur also with brown macula apically ( Figs 112–113 ). Tibiae, tarsi and claws of all legs pale ocher. Abdominal segments I–VI colorless, segments VII–X pale yellowish, tergites I–VII with following larger or smaller contrasting reddish or brown markings: tergite I with transverse line bordering posterior margin; tergites II–VII with unpaired median spot near anterior margin and pair of transverse stripes near posterior margin; tergites III, V and VI, besides it, with pair of short oblique stripes on lateral parts. Lateral tracheal trunks and bases of sternal tracheae either colorless, or partly colored by black or brown. In proximal part of cercus, middle part of each segment ocher, area around each segment colorless; distal part of cercus entirely colorless.

STRUCTURE. Turbinate eyes with facetted surface wider than stem ( Figs 110, 113 ). Pterostigma with 3–5 oblique veins. Two marginal intercalaries nearly in each space (except few posterior ones), length of most intercalaries less than distance between adjacent longitudinal veins (as in Fig. 32 ). Hind wing absent. Middle and hind tarsus long (about 0.7 of tibia length), its 1st+2nd segment subequal to 3rd, 4th and 5th segments together ( Table 5). Genitals as in Fig. 118 : surface between unistyligers striated; gonovectes sharply bent; median sternostyligeral muscle slender, consists of pair of separate bunches, which are convergent V-shaped.

Imago, female. COLORATION ( Figs 114–115 ). Head ocher. Thorax ocher; mesonotum without pair of anterolateral dark stripes characteristic for male. Coloration of wing veins as in male, but somewhat darker. Coloration of legs as in male. Abdomen ocher, with contrasting reddish or brown markings arranged as in male.

STRUCTURE. Eyes relatively large, elevated above head surface ( Figs 114–115 ). Wing with one marginal intercalary in some spaces and no one marginal intercalary in other spaces; in other respects wing venation as in male.

Egg. Oval, 0.1 mm length. Chorion irregularly crumpled, without relief (as in Figs 145, 146 ).

Dimension. Fore wing length: male 4.0– 4.1 mm; female 4.2 mm.

Distribution. Peruvian Amazonia.

Comparison. Larva of Cloeodes nigrohumeris sp. n. is similar to C. spaceki by long claws, shape of distal dentiseta of maxilla, widened distal segment of labial palp and cuticular coloration of abdomen; judging by the photo of mature larva ready to molt to subimago ( Massariol et al. 2013: Fig, 7), male subimago and imago of C. spaceki has a pair of contrasting dark stripes on mesonotum as in C. nigrohumeris sp. n. Larva of the new species C. nigrohumeris sp. n. differs from C. spaceki by constant presence of reddish hypodermal markings on abdomen ( Figs 92–93 ) and by peculiar subapical seta on dorsal side of glossa ( Fig. 108 ). Tergalius IV of C. spaceki is figured as rounded apically ( Massariol et al. 2013: Fig, 42b), while tergalii of C. nigrohumeris sp. n. are pointed ( Fig. 122 ). This difference can be either species-specific, or caused by poor condition of tergalii in the type series of C. spaceki (F.F. Salles, personal communication).

Figures

FIGURES 92 – 97. Cloeodes nigrohumeris sp. n. 92, immature last instar male larva; 93 – 96, mature last instar male larva ready to molt to subimago: 93, intact condition; 94, its detached cuticle of pronotum and mesonotum; 95, its extracted abdomen with hypodermal coloration; 96, its detached cuticle of abdomen. 97, middle of posterior margin of abdominal tergum IX. Abbreviations: I – X, abdominal segments I – X.

FIGURES 98 – 103. Cloeodes nigrohumeris sp. n. 98 – 99, subimaginal exuviae: 98, half of mesonotum; 99, part of meso- and metapleuron with postsubalar sclerite and lateropostnotal crest; 100 – 103, larval exuviae: 100 – 101, abdomen and caudalii; 102, left thoracic pleura, legs and half of metanotum; 103, half of pronotum and mesonotum (99, holotype).

FIGURES 104 – 109. Cloeodes nigrohumeris sp. n., larva. 104 – 105, left and right mandibles; 106, labrum (apical setae not shown); 107, paraprocts; 108, labium (left half in ventral view; right half in dorsal view); 109, apex of maxilla (104 – 106, 108 – 109, holotype). Abbreviations: ds 1, ds 2, ds 3, dentisetae.

FIGURES 110 – 115. Cloeodes nigrohumeris sp. n. 110, male imago and its enlarged wing margin; 111, male imago; 112, fore leg of male imago; 113, middle leg of male imago; 114, female imago and its enlarged wing margin; 115, female imago.

FIGURES 116 – 118. Cloeodes nigrohumeris sp. n. 116, subimaginal gonostyli extracted from mature larva; 117, exuviae of subimaginal genitals; 118, genitals of male imago (gonovectes shown by interrupted line; at right half gonovectal and gonostylar muscles shown by interrupted lines; median styligeral muscle shown by interrupted lines, areas of anterior attachment of median paraproctal muscles shown by dotted lines) (117 – 118, holotype). Abbreviations: 1, 2, 3, segments of gonostylus; m. IX-X, areas of anterior attachment of median paraproctal muscles (i. e., muscles going from sternum IX to common base of paraprocts); m. sg, median sterno-styligeral muscle; usg, unistyliger.

FIGURES 119 – 132. Cloeodes spp., tergalii. 119 – 125, tergalii I – VII of Cloeodes nigrohumeris sp. n.; 126 – 132, tergalii I – VII of Cloeodes auwe. For both individuals vertical line corresponds to length of abdominal segment IV.

FIGURES 37 – 57. Cloeodes spp., tergalii. 37 – 43, tergalii I – VII of Cloeodes vibratorius sp. n.; 44 – 57, tergalii I – VII of two individuals of Cloeodes redactus. For all three individuals vertical line corresponds to length of abdominal segment IV.

FIGURES 6 – 12. Cloeodes vibratorius sp. n., larva. 6, head of female larva; 7, maxilla; 8, apex of maxilla; 9 – 11, left and right mandibles; 12, labrum (apical setae not shown) (10, 12, holotype). Abbreviations: ds 1, ds 2, ds 3, dentisetae.

FIGURES 13 – 17. Cloeodes vibratorius sp. n. 13, labial palp; 14, labium (left half in ventral view with muscles shown by interrupted lines; right half in dorsal view); 15, paraprocts; 16, tibia of fore leg, anterior view (seta and suture on opposite side shown by interrupted lines; only two setae of proximal arched row are shown); 17, tarsus of hind leg, view from outer side (13, holotype).

FIGURES 18 – 25. Cloeodes vibratorius sp. n. 18 – 23, larval exuviae: 18, tergum IX; 19, paraprocts; 20, portion of sternum IV with setal row; 21, fore leg; 22, middle leg and half of metanotum; 23, hind leg; 24 – 25, subimaginal exuviae: 24, left half of mesonotum; 25, postsubalar sclerite and lateropostnotal crest (21 – 23, holotype).

FIGURES 32 – 36. Cloeodes vibratorius sp. n. 32, fore wing of male; 33, subimaginal gonostyli developing under larval cuticle; 34, exuviae of subimaginal genitals; 35, genitals of male imago (gonovectes shown by interrupted line; at right half gonovectal and gonostylar muscles shown by interrupted lines; median styligeral muscle shown by interrupted lines, areas of anterior attachment of median paraproctal muscles shown by dotted lines); 36, gonostylus (32, 34 – 35, holotype). Abbreviations: 1, 2, 3, segments of gonostylus; m. IX-X, areas of anterior attachment of median paraproctal muscles (i. e., muscles going from sternum IX to common base of paraprocts); m. sg, median sterno-styligeral muscle; usg, unistyliger.

FIGURES 145 – 146. Eggs. 145, Cloeodes vibratorius sp. n.; 146, Cloeodes redactus.