Crassabwa, Lugo-Ortiz & McCafferty, 1996

Kluge, Nikita J., Gattolliat, Jean-Luc, Salles, Frederico F. & Novikova, Eugenia A., 2018, Revision of the Afrotropical genus Susua Lugo-Ortiz & McCafferty 1998 (Ephemeroptera: Baetidae: Protopatellata), Zootaxa 4434 (1), pp. 1-28 : 26-27

Key to larvae of Crassabwa /g1

1. Larva of Baetidae with the following combination of characters: Claw shallowly bent, with 2 rows of denticles ( Figs 19 , 70 ). Labial palp «chelate», i.e. with inner-apical projection of 2nd segment ( Figs 5 , 69 ). Hind protoptera present, i.e. winged stages have hind wings....................................................................................... 2

- Some of these characters absent: either claw sharply bent and/or with 1 row of denticles, or labial palp non-chelate (i.e., without inner-apical projection of 2nd segment), or hind protoptera absent or vestigial (i.e. winged stages have no hind wings)............................................................................................ other Baetidae .

2. Outer side of each femur, besides a row of stout setae, with 2 stout subapical setae brought together ( Kluge 2016: Figs 21, 25, 26 ). This combination of characters is present in the following taxa: (1) New World genus Paracloeodes Day 1955 , belonging to Baetovectata (in larva patella-tibial suture on fore leg present, in adult fore wing with 2 marginal intercalaries per space); (2) Old World genus Cheleocloeon Wuillot & Gillies 1993a , belonging to Anteropatellata-non-Baetovectata (in larva patella-tibial suture on fore leg present, hind protoptera only in male, in adult fore wing with 1 marginal intercalary per space); (3) Afrotropical genus Bugilliesia Lugo-Ortiz & McCafferty 1996c , belonging to Protopatellata (in larva patella-tibial suture on fore leg absent, in adult fore wing with 1 marginal intercalary per space); and (3) poorly known species Delouardus djabala Lugo-Ortiz & McCafferty 1999 in Madagascar. - Outer side of each femur, besides a row of stout spatulate setae, with 1 stout spatulate subapical seta ( Fig. 18 ). Members of Protopatellata: in larva patella-tibial suture on fore leg absent ( Figs 13–15 ), in adult fore wing with 1 marginal intercalary per space ( Fig. 50 ). Claw with two most distal denticles of each row enlarged ( Figs 19 , 70 ) ( Crassabwa /g1)................. 3

3. Tergalius I in proximal half with anal margin concave and armed by slender rib, without portion bent ventrally ( Figs 20 , 72 ). Abdominal terga II–VI either without denticles, or with irregular denticles alternating with scales ( Fig. 37 ) ( Susua )........ 4

- Tergalius I in proximal half with anal margin convex, not bordered by rib; in last larval instar its anal portion usually bent ventrally ( Kluge et al. 2017: Figs 23 , 84 ). Abdominal terga I–X with regular row of pointed denticles on posterior margin ( Kluge et al. 2017: Fig. 20 ) ( Crassabwa )......................................................................... 5

4. Tergalius I as long as tergalius II ( Figs 20–21 ). Mesonotum with sharply projected median ridge ( Fig. 41 ). Pronotum with 1 pair of tufts of spatulate setae, mesonotum with 2 or more pairs of tufts of spatulate setae ( Figs 28–31 ). Legs relatively slender ( Figs 13–15 ).............................................................................. Susua sigiensis

- Tergalius I much longer than tergalius II ( Figs 72–73 ). Mesonotum without prominent median ridge ( Fig. 78 ). Pronotum and mesonotum without tufts of spatulate setae ( Fig. 87 ). Legs relatively thick ( Figs 91–93 )............... Susua niandanensis

5. In last instar larva, cuticle of fore protopteron with dark lines corresponding to convex longitudinal veins only ( Kluge et al. 2017: Fig. 4 ). Mola of left mandible with even row of denticles ( Kluge et al. 2017: Fig. 8 )............... Crassabwa flava

- In last instar larva, cuticle of fore protopteron with dark lines corresponding to convex, concave and cross veins ( Kluge et al. 2017: Fig. 62 ). Mola of left mandible with tubercles bearing denticles ( Kluge et al. 2017: Fig. 81 )..................... 3

6. Claw relatively short, with portion from distal denticle to apex shorter than portion from distal denticle to base ( Kluge et al. 2017: Figs 66 , 95 )..................................................................... Crassabwa ludmilae

- Claw relatively long, with portion from distal denticle to apex longer than portion from distal denticle to base ( Kluge et al. 2017: Fig. 126)........................................................................ Crassabwa ameliae

Figures

FIGURES 17–27. Larva of Susua sigiensis. 17, base of tibia of fore leg, anterior view (setae on posterior side shown by interrupted lines); 18, apex of femur and base of tibia of middle leg, anterior view (setae on posterior side shown by interrupted lines); 19, claw; 20–26, tergalii I–VII; 27, paraproct.

FIGURES 69–77. Susua niandanensis from Zambia. 69, labium (at left ventral view; at right dorsal view); 70, larval claw; 71, hind wing of female imago (interrupted line shows lost part of costal projection); 72–73, tergalii I–II; 74–76, tergalii V–VII; 77, paraproct.

FIGURES 5–9. Larva of Susua sigiensis. 5, labium (at left ventral view with muscles of glossa, paraglossa and palp shown by interrupted lines; at right dorsal view); 6, labrum (dorsal view); 7, apex of left maxilla; 8–9, biting edges of left and right mandibles. Abbreviations: ds1, ds2, ds3, dentisetae.

FIGURES 10–16. Exuviae of last instar larvae of Susua sigiensis. 10, caudalii; 11, right half of pronotum and mesonotum; 12, abdominal sterna, terga and caudalii; 13, fore leg; 14, middle leg with meso- and metathoracic pleura, half of metanotum and hind protopteron; 15, hind leg; 16, labium. Abbreviations: I–X, abdominal segments I–X; ppt, hind protopteron. Black triangle shows point where patella-tibial suture crosses inner margin.

FIGURES 47–51. Susua sigiensis. 47–48, female imago, dorsal and ventral view; 49, subimaginal exuviae of left pleuron; 50, male imago; 51, male imago with subimaginal exuviae.

FIGURES 34–40. Exuviae of abdomen of last instar larva of Susua sigiensis. 34, tergum I; 35, tergum II; 36, tergum V; 37, tergum VIII; 38, tergum IX (black triangle shows midline); 39, tergum X; 40, sternum VII.

FIGURES 78–86. Susua niandanensis from Zambia. 78–79, male larva of last instar; 80–81, exuviae of last instar female larva (80, right half of pronotum and mesonotum; 81, abdominal sterna, terga and caudalii); 82–84, parts of last instar male larva (82, pronotum and mesonotum; 83, metanotum; 84, abdomen); 85, subimaginal abdominal sterna and terga extracted from mature male larva; 86, abdominal terga and sterna of female imago (the same specimen as in Figs 80–81). Abbreviations: I–X, abdominal segments I–X.

FIGURES 41–46. Susua sigiensis. 41, anterior part of larva; 42, anterior part of female imago; 43–44, hind leg of imago and its subimaginal exuviae; 45–46, the same of another specimen. Abbreviations: R, unpaired median ridge on mesonotum; S, paired bunches of spatulate setae on pronotum and mesonotum.

FIGURES 28–33. Exuviae of left half of pronotum and mesonotum of last instar larva of Susua sigiensis. 28, general view; 29–31, bunches of spatulate setae on places shown by arrows; 32, scales on pronotum; 33, scales on posterior part of fore protopteron.

FIGURES 87–90. Exuviae of left half of pronotum and mesonotum of last instar larva of Susua niandanensis from Zambia. 87, general view; 88, scales on pronotum; 89, scales on mesonotum; 90, scales on posterior part of fore protopteron.

FIGURES 91–96. Susua niandanensis. 91–92, hind femora of two specimens from Guinea (type locality); 93–95, exuviae of last instar larva from Zambia: 93, hind leg (black triangle shows point where patella-tibial suture crosses inner margin); 94, tergum V; 95, tergum VII; 96, sternum IX.

FIGURES 1–4. Holotype of Susua sigiensis: 1, dorsal view; 2–3, genitalia; 4, larval exuviae.

FIGURES 62–68. Last instar larvae of Susua niandanensis from Zambia. 62, exuviae of labium; 63, base of labium with focus on ventral side; 64, the same with focus on dorsal side; 65, detached cuticle of mle head with labrum, mandibles and bases of antennae (with subimaginal antennae inside); 66, apex of maxilla (with focus on dentisetae and inner-dorsal row of setae); 67– 68, left and right mandibles. Abbreviation: d-l, dorso-lateral sclerite.