Pseudopannota camerunense ( Ulmer 1920 ) Ulmer, 1920

Kluge, Nikita J. & Novikova, Eugenia A., 2016, New tribe Labiobaetini tribus n., redefinition of Pseudopannota Waltz & McCafferty 1987 and descriptions of new and little known species from Zambia and Uganda, Zootaxa 4169 (1), pp. 1-43 : 20-28

Pseudopannota camerunense ( Ulmer 1920) comb. n.

( Figs 3 , 11–13 , 18 , 21–22 , 59–90 )

Pseudocloeon camerunense Ulmer 1920: 57 (♂ imago);

Pseudocloeon sp. A: Kimmins 1955: 855 (larva; Nyasaland) ; Agnew 1963: 43 ( South Africa and Southern Rhodesia) ; Ophelmatostoma kimminsi Waltz & McCafferty 1987: 97 (larva; Malawi and Senegal);

Ophelmatostoma camerunense: Gillies, Elouard & Wuillot 1990: 116 (♂ and ♀ imago and larva; West Africa; = O. kimminsi ).

Material examined. ZAMBIA: river Luangwa near Luangwa Bridge , 2–8.VIII.2014, coll. N. Kluge & L. Sheyko: 11 female ultimolarvae , 2 female penultimolarvae; river West Lunga near Mwinilunga , 14–21.VIII.2014, coll. N. Kluge & L. Sheyko: 3 L-S-I ♂, 1 L-S/I ♂, 2 L-S-I ♀, 29 ultimolarvae, 4 penultimolarvae ; river Mudanyama in Mwinilunga , 14–21.VIII.2014, coll. N. Kluge & L. Sheyko : 4 I ♂, 13 I ♀, 1 ultimolarva; river Zambezi near Victoria Falls , 25–31.VIII.2014, coll. N. Kluge & L. Sheyko: 1 IƋ, 1 ultimolarva.

Descriptions. Larva. CUTICULAR COLORATION. Head brown with unpaired longitudinal blank along occipital suture and transverse blank in front of ocelli. Legs of each pair light with following brown bands: two bands on femur, one band on proximal part of tibia, sometimes one band on proximal part of tarsus ( Figs 59, 60 ). Tergalii light brownish, with margins lighter ( Fig. 62 ). Caudalii unicolor light brownish.

Cuticular coloration of thorax and abdomen markedly different in different larval instars. In ultimolarva, dorsal side brown with integral unpaired wide longitudinal blank stretching from head to tip of abdomen ( Figs 60–62 ): pronotum brown with unpaired median longitudinal blank and colorless lateral margins; mesonotum brown with unpaired median longitudinal blank and pair of very mall round lateral blanks; metanotum and abdominal terga I– IX brown with unpaired median longitudinal blank bordered by dark brown areas; abdominal tergum X lighter than others or colorless. This coloration is more contrasting in specimens from rivers West Lunga and Zambezi, and less contrasting in specimens from river Luangwa.

In penultimolarva, dorsal side brown with lighter and darker areas not forming integral longitudinal line ( Figs 63, 64 ): pronotum brown with several paired blanks and colorless lateral margins; mesonotum with paired and unpaired blanks; metanotum and abdominal terga I, III–V and VII–IX light brown with or without unpaired median longitudinal blank; abdominal terga II and VI brown with median part entirely dark brown; abdominal tergum X colorless.

HYPODERMAL COLORATION. Absent; only in mature larva ready to molt to subimago, subimaginalimaginal coloration of abdominal terga can be visible through larval cuticle.

STRUCTURE. Body relatively slender ( Figs 59, 60 ). Frons between antennae bases flat and bordered by pair of ridges; frontal suture blunt-angled ( Fig. 72 ). Distal margin of frons sharply projected above clypeus ( Fig. 59 ; Waltz & McCafferty 1987: Fig. 2 ).

Labrum with lateral margins straight, with numerous long setae on lateral margins and on outer side close to lateral margins ( Figs 74–76 ); distal margin [soft, with numerous fine setae—see Pseudopannota (1)] with poorlyexpressed median incision; inner side with paired row of spine-like setae, with asymmetric sclerite [see Pseudopannota (1)]. Incisor of left and right mandible represented by one small denticle [see Pseudopannota (2)]; protuberance proximad of right prostheca blunt [see Pseudopannota (3)] ( Figs 77–79 ). Maxilla as characterized above [see Pseudopannota (4, 5)], widest in distal half ( Fig. 12 , 70 ).

Maxillary palp ( Figs 11–13 , 70, 71 ) very slender, with primary first segment undivided, without intrinsic muscle. Proximal part of first segment entirely with membranous cuticle, on inner side with numerous campaniform sensilla. Distal part of first segment on outer side with cuticle sclerotized and colored with light grayish. Second segment on outer side with cuticle sclerotized and colored with light grayish; terminates by small slender portion with membranous cuticle, covered with numerous irregular soft colorless setae.

Labium greatly modified ( Figs 68, 69 ). Mentum spherically projected, with paraglossal muscle strengthened and running at most dorsoventrally, rather than longitudinally. Glossa in proximal part sharply bent; glossae and paraglossae unusually long, cylindrical, without any setae on cylindrical surface, each with roundish-conic apex surrounded by regular row of very long setae; setal row of glossa forms nearly integral ring with several long setae inside ( Fig. 69 ); setal row of paraglossa forms integral ring with few smaller setae in its center. Distal segment of labial palp [formed by fusion of 2nd and 3rd primary segments—see Pseudopannota (8)] slender, petiolate, thickened distally; its slender proximal part lacks setae; thickened distal part with stout setae on inner margin, sparse long irregular setae on ventral surface near outer margin and with numerous long and short setae on dorsal surface.

Mesonotum with antero-lateral corners projected anteriorly ( Figs 61, 62 ). Fore protoptera not fused ( Fig. 18 ). Vestiges of hind protoptera present ( Fig. 73 ).

Coxa of each leg with pointed lobe ( Figs 82, 83 ). Fore femur thickest proximally, middle and hind femora thinner ( Figs. 82, 83 ). Outer margin of each femur with sparse small pointed stout setae; fore femur, besides it, with pointed setae on anterior surface ( Fig. 83 ). No structures resembling femoral patch of Baetofemorata. Fore tibia with irregularly situated pointed setae on anterior surface ( Fig. 83 ). Tibiae of middle and hind legs and tarsi of all legs with small stout spine-like setae on inner side. Patella-tibial suture equally developed on all legs. Each claw with 4–7 small denticles of equal size ( Figs 21, 22 ).

Surface of abdominal terga and sterna without denticles, with scales in wide semicircular sockets. Posterior margin of each tergum I–X with regular denticles, shorter and blunt on tergum I, longer and pointed on other terga. Sterna I–V with posterior margin entirely smooth, sterna VI and VII with few small denticles on lateral parts of posterior margin, sterna VIII and IX with pointed denticles on posterior margin ( Fig. 80 ). Paraprocts with many short marginal denticles.

Tergalii oval, with anal margin more convex than costal margin; margin entirely bordered by well-developed rib, serrate; surface without denticles, with scales in wide semicircular sockets (as on terga); tracheae colored, well visible ( Fig. 62 ). Tergalius I shorter than 1/2 of tergalius II, tergalius IV largest.

Cerci somewhat shorter than body length, paracercus somewhat shorter than cerci ( Fig. 59 ). Posterior margins of segments of cerci and paracercus with equal triangular denticles, subequal to denticles on posterior margin of abdominal terga.

Subimago. CUTICULAR COLORATION. Cuticle at most colorless. Pronotum colorless. Mesonotum very light, partly colorless, with anterolateral scutal costa contrastingly bordered by dark brown (as in Fig. 29 ). Thoracic pleura at most colorless, with contrasting dark brown lines along prealar bridge, lateropostnotal crest and its junction with postsubalar sclerite and some other sclerites; anterior part of postsubalar sclerite colorless (as in Fig. 30 ). Legs entirely colorless. Abdomen, gonostyli and cerci entirely colorless.

TEXTURE. On fore leg of male 1st–4th tarsomeres covered by blunt microlepides, 5th tarsomere covered by pointed microlepides; on other legs of male and all legs of female all tarsomeres covered by pointed microlepides (see Table 2 ).

Imago, male ( Figs 65, 66 ). Head brown and ocher. Turbinate eyes widened apically, with facetted surface red, stem light reddish-orange. Thorax with brown and ocher areas; medial line of mesonotum dark brown. Wing membrane colorless, veins ocher. Pterostigma with few oblique incomplete veins (Gillies et al. 1990: Fig. 2 ). Hind wing absent. Legs unicolor ocher, slender, with tarsus relatively short; tarsus of middle and hind leg with 2 apical spines, on segments 1st+2nd and 3rd ( Fig. 84 ). Abdomen ocher with reddish-brown markings: terga II–IV with small paired markings; terga V–VIII either nearly entirely reddish-brown, or with median area lighter; terga IX and X reddish-brown in anterior part and lighter in posterior part. Cerci unicolor ocher.

Male genital structure and development. Imaginal genitals as in Figs 3 , 81 , 85, 86 . Sterno-styligeral muscle completely absent. Each gonovectis with apex free end straight, not hooked and not bordering distal margin of membranous sack. Penial bridge forms prominent median projection rounded apically. Apical margin of each unistyliger medially with roundish projection directed distally. Gonostylus with 1st segment long and nearly parallel-sided, with inner margin projected as blunt angle; 2nd segment slightly widened toward apex; 3rd segment short.

Protogonostyli of male larva represent very shallow convexities of posterior margin of abdominal sternum IX. In mature larva ready to molt to subimago, subimaginal gonostyli are packed under larval cuticle in « Labiobaetis - pose»: second segments directed medially and bent ( Fig. 80 ).

Imago, female ( Fig. 67 ). Thorax and wings as in male. Tarsus of fore leg with 2 apical spines, on segments 2nd and 3rd; middle and hind legs as in male. All abdominal terga with contrasting ocher median area and reddishbrown lateral areas.

Eggs ( Figs 87–90 ). About 0.1 mm length. Oval or nearly spherical, with large irregular folds and irregular craters of variable size and shape.

Dimension. Fore wing length of male and female about 6 mm.

Discussion. Gillies, Elouard and Wuillot (1990) established synonymy between Ophelmatostoma kimminsi (originally described as larva) and Pseudocloeon camerunense (originally described as male imago) based on comparison of male imagoes reared from larvae with descriptions of these species. Drawing of genitals in the original description of P. camerunense contains such evidently wrong details as a line separating 1st and 2nd segments of gonostylus (wrongly named “Gleid II” and “Gleid III”) and median projection overlapping unistyliger from ventral side; shape of unistyligers and gonostyli is somewhat different from described above ( Ulmer 1920: Fig. 42 ). Syntypes of P. camerunense are deposited in the Zoologische Staatssammlung München. They are preserved in alcohol, but crumpled (probably, were dried out). Four of these syntypes were examined by us. Genitals of one of them were treated by alkali, that allowed to see that their structure is exactly the same as genital structure of the specimens reared from larvae in Zambia: medio-apical angle of unistyliger is slightly projected caudally-dorsally, first segment of gonostylus has angulate inner margin, apex of gonovectis is straight and pointed ( Figs 85, 86 ). This allow to confirm the synonymy of P. camerunense and O. kimminsi .

Kimmins (1960) reported male imagoes from Lake Victoria in Uganda, which he determined as Pseudocloeon camerunense , but noted some difference. Possibly, they are conspecific with imagoes from the same locality, which I presumably ascribe to Pseudopannota sp. U (see above).

Distribution. Guinea, Côte d'Ivoire, Mali, Nigeria, Senegal, Sierra Leone, Cameroon, Malawi (= Nyasaland), Zimbabwe (= Southern Rhodesia), South Africa ( Kimmins 1955; Agnew 1963; Elouard, Gillies & Wuillot 1990); Zambia (present study).

Figures

FIGURES 1 – 3. Labiobaetini, genitals of male imago, ventral view. 1, Labiobaetis tenuicrinitus (Kopelke 1980) (pair of median paraproctal muscles are visible through integument); 2, Pseudopannota pannota sp. n. (median paraproctal muscles removed, only their extreme bases retained); 3, Pseudopannota camerunense (Ulmer 1920) (median paraproctal muscles removed, only their proximal parts retained). Abbreviations: mIX-X, median paraproctal muscles (i. e. muscles going from sternum IX to common base of paraprocts)

FIGURES 8 – 15. Labiobaetini, maxillary palp. 8, ultimolarval exuviae of Labiobaetis tenuicrinitus (Kopelke 1980); 9, ultimolarva of Pseudopannota fusca sp. n.; 10, its exuviae; 11 – 13, Pseudopannota camerunense (Ulmer 1920): 11, penultimolarva; 12, penultimolarval exuviae; 13, ultimolarval exuviae; 14, ultimolarval exuviae of Pseudopannota pannota sp. n.; 15, ultimolarval exuviae of Pseudopannota sp. U. Abbreviations: 1, 2, primary first and second segments of maxillary palp; 1 d, 1 p, distal and proximal subsegments of primary first segment.

FIGURES 16 – 20. Labiobaetini: fore protoptera of immature ultimolarvae (hypoderm with veins visible through cuticle). 16, Labiobaetis tenuicrinitus (Kopelke 1980); 17, Pseudopannota pannota sp. n.; 18, Pseudopannota camerunense (Ulmer 1920); 19, Pseudopannota maculosa (Crass 1947); 20, Pseudopannota fusca sp. n.

FIGURES 21 – 25. Pseudopannota, larval claws. 21 – 22, P. camerunense (Ulmer 1920); 23 – 24, P. f us c a sp. n.; 25, P. pannota sp. n.

FIGURES 59 – 64. Pseudopannota camerunense (Ulmer 1920). 59 – 62, ultimolarvae from river West Lunga: 59, lateral view; 60, exuviae, dorsal view; 61, exuviae of left half of pronotum and mesonotum; 62, exuviae of abdomen; 63 – 64, penultimolarva from the same locality: 63, exuviae of pronotum and mesonotum; 64, exuviae of abdomen.

FIGURES 65 – 67. Pseudopannota camerunense (Ulmer 1920). 65, 66, male imago, lateral and dorsal view; 67, female imago, dorso-lateral view.

FIGURES 68 – 73. Pseudopannota camerunense (Ulmer 1920). 68, labium, ventral view (at left half, muscles shown by interrupted lines; long setae not shown, their bases shown by rings); 69, apex of glossa, dorsal view (long setae not shown, their bases shown by rings, setal bases on opposite side shown by interrupted lines); 70, left maxilla of ultimolarva (muscles shown by interrupted lines); 71, maxillary palp of penultimolarva; 72, head of female ultimolarva; 73, margin of ultimolarval metanotum with vestige of hind protopteron. Abbreviations: 1 d, 1 p, areas corresponding to distal and proximal subsegments of primary first segment of maxillary palp; 2, second segment of maxillary palp; ds 1, ds 2, ds 3, dentisetae.

FIGURES 74 – 79. Pseudopannota camerunense (Ulmer 1920). 74 – 76, labrum: 74, intact exuviae, view from outer side (outer and inner walls visible at the same time); 75, cuticle spread on slide (outer wall above, inner wall below); 76, enlarged distal part of inner wall; 77 – 79, left and right mandibles. Abbreviations: as, asymmetric sclerite on inner side of labrum; d, distal margin of labrum; i-d, inner side of distal membranous area; o-d, outer side of distal membranous area; in, incisor.

FIGURES 80 – 84. Pseudopannota camerunense (Ulmer 1920). 80, subimaginal gonostyli folded under larval cuticle (1, 2, 3, segments of gonostylus); 81, genitals of male imago (at left half, muscles shown by interrupted lines; places of attachment of median paraproctal muscles shown by dotted lines; 1, 2, 3, segments of gonostylus); 82 – 84, legs, anterior view (at the same scale): 82, larval middle leg; 83, larval fore leg; 84, imaginal middle leg (1, 2, 3, 4, 5, tarsomeres). Abbreviations: gv, gonovectis; pgs, protogonostylus (paired convexity on posterior margin of IX sternum of male larva); mIX-X, areas of anterior attachment of median paraproctal muscles (i. e., muscles going from sternum IX to common base of paraprocts); pb, median projection of penial bridge; usg, unistyliger.

FIGURES 85 – 90. Pseudopannota camerunense (Ulmer 1920). 85, genitals of syntype, treated by alkali, in water, ventrolateral view; 86, the same, focused on gonovectis; 87 – 90, eggs.

FIGURES 26 – 33. Pseudopannota pannota sp. n. 26 – 27, male imago, lateral and dorsal view; 28, female imago, dorsal view; 29, subimaginal exuviae of left half of mesonotum with left wing; 30, subimaginal exuviae of left pleurite with postsubalar sclerite and lateropostnotal crest; 31, ultimolarva, lateral view; 32, ultimolarval exuviae of left half of pronotum and mesonotum; 33, its exuviae of abdominal terga and sterna (29, 30, 32, 33, holotype).

FIGURES 38 – 49. Pseudopannota pannota sp. n., larva. 38, distal margin of labrum, with focus on inner side; 39, the same, with focus on outer side; 40 – 42, left and right mandibles; 43, exuviae of labium, with focus on fine setae on ventral side of distal segment of palp; 44, hypopharynx; 45, abdominal tergum VIII; 46 – 48, tergalii I, II and VII; 49, paraprocts (43, 49, holotype).