Centroptiloides ornatus, Gillies, 2001

Gillies, M. T., 2001, New species of Baetidae (Ephemeroptera) from the Upper River Sigi, Usambara, Tanzania, Journal of Natural History 35 (1), pp. 23-32 : 26-28

Centroptiloides ornatus sp. n.

(®gures 12±14, 17, 19±25, 27±29)

Centroptiloides sp. n., Gillies, 1998: 53.

Male imago (in life). Turbinate eyes black. Thorax generally sandy-brown, mesonotum mustard; fore femur reddish brown, tibia chocolate, this becoming more intense apically; tarsus 1 black, 2±4 clear except for apical 1/4 which is dark grey, tarsus 5 grey; mid and hind legs cream, femora diOEusely tinged with red. Fore wing (®gure 12), costal and subcostal areas yellowish brown, rest of wing ®eld hyaline, all cross-veins black, the pigment spreading out on to adjacent wing membrane. Abdomen conspicuously marked in chocolate on a cream background, lateral margins of II±IX diOEusely maroon; forceps dark grey, tails greyish brown with red annulations.

(In spirit). Turbinate eyes ovoid, contiguous, purplish black. Thorax generally pale buOE, metanotum orange-yellow. Fore femur yellowish, tibia (®gure 17) medium brown turning to umber at apex, tarsus I umber, tarsi II±IV clear, dark brown at apices giving a ringed eOEect, tarsus V dark brown. Wings (®gures 12, 13). Abdomen, tergal markings (®gure 19), venter entirely pale except for dark grey colour of long forceps segment (®gure 20). Cerci pale grey.

Female imago (in spirit). Thorax pale buOE: fore femur, tibia and tarsus I dark brown, femur paler at base, tarsus 2±5 pale. Wings (®gure 14) as male but pigmented spots larger. Abdomen, terga II±VII with postero-median margins dark brown, the dark areas narrower on posterior segments, terga II±III, V±IX with dark median streak; venter pale.

Subimago. Wing membrane dark brown with extensive pale windows giving a dappled eOEect. Abdominal terga II±VII broadly dark-banded posteriorly and with a broad, dark, lateral stripe; sterna pale, unmarked.

Body: male 9±9.5 mm, female 9.5 mm. Wing: male 9 mm, female 10 mm.

Larva. Body pale brown, without obvious markings. Mouthparts (®gures 21±25). Labrum deeply excavated in midline, upper surface with a uniform covering of short setae; canines of mandibles sharply pointed, molar surface reduced to a single broad tooth, right prostheca a stout bi®d process; maxillary palp two-segmented, apical teeth of galea-lacinia stout, sharp, subapical setae stout; labial palp very broad, with two segments, distal segment strongly ¯exed.

Fore leg (®gures 27, 28) short and broad, setation con®ned to short, stout hairs along anterior margins of tibia and tarsus and ®ner hairs along basal half of posterior margin of femur, tarsal claw stout with a double row of six or seven blunt teeth; tibio-patellar seam absent from fore leg, present on mid and hind legs.

Gill lamellae on segments I±VII (®gure 29) palette-shaped with well-developed basal lobe not forming a distinct basal ¯ap. Posterior margins of abdominal terga with uniform, closely packed teeth. Paraprocts with 15±20 marginal spines. Median caudal ®lament about two-thirds length of cerci.