Alboglossiphonia buniana Jueg, 2023

Jueg, Uwe, 2023, Alboglossiphonia afroalpina sp. nov. and Alboglossiphonia buniana sp. nov. - two new leech species from Africa and revision of the genus Alboglossiphonia Lukin, 1976 in Africa, Evolutionary Systematics 7 (1), pp. 1-34 : 1

Alboglossiphonia buniana Jueg sp. nov.

Material.

A total of 25 specimens from two localities in Bunia in the Democratic Republic of Congo were examined, and are deposited in the Royal Museum of Central Africa in Tervuren ( Belgium). They were labeled Glossiphonia disjuncta Moore, 1939 .

Holotype: 1 specimen, Democratic Republic of Congo, Ituri Province , Bunia, near the border with Uganda at Lake Albert , Jardin de Peres , leg. Courtois et Dr. Masse, 02.03.1952 (in Sciacchitano 1952 as Glossiphonia disjuncta Moore , 1939), on Lymnaea natalensis succinoides et Biomphalaria ruppellii (= Radix natalensis ( Krauss , 1848) and Biomphalaria pfeifferi ( Kraus , 1848)); deposited at the Royal Museum of Central Africa in Tervuren ( Belgium), Coll.-No.: RMCA_VERMES_43662 (specimen 1 in Table 2 ).

Paratypes: 19 specimens with the same locality as the holotype .

Paratype 1: RMCA_VERMES_43663 (specimen 2 in Table 2 )

Paratype 2: RMCA_VERMES_43664 (specimen 3 in Table 2 )

Paratype 3: RMCA_VERMES_43665 (specimen 4 in Table 2 )

Paratype 4: RMCA_VERMES_43666 (specimen 5 in Table 2 )

Paratype 5: RMCA_VERMES_43667 (specimen 6 in Table 2 )

Paratype 6: RMCA_VERMES_43668 (specimen 7 in Table 2 )

Paratype 7: RMCA_VERMES_43669 (specimen 8 in Table 2 )

Paratype 8: RMCA_VERMES_43670 (specimen 9 in Table 2 )

Paratype 9: RMCA_VERMES_43671 (specimen 10 in Table 2 )

Paratype 10: RMCA_VERMES_43672 (specimen 11 in Table 2 )

Paratype 11: RMCA_VERMES_43673 (specimen 12 in Table 2 )

Paratype 12: RMCA_VERMES_43674 (specimen 13 in Table 2 )

Paratype 13: RMCA_VERMES_43675 (specimen 14 in Table 2 )

Paratype 14: RMCA_VERMES_43676 (specimen 15 in Table 2 )

Paratype 15: RMCA_VERMES_43677 (specimen 16 in Table 2 )

Paratype 16: RMCA_VERMES_43678 (specimen 17 in Table 2 )

Paratype 17: RMCA_VERMES_43679 (specimen 18 in Table 2 )

Paratype 18: RMCA_VERMES_43680 (specimen 19 in Table 2 )

Paratype 19: RMCA_VERMES_43681 (specimen 20 in Table 2 )

Additional material.

5 specimens; Democratic Republic of Congo, Ituri Province , Bunia, with Biomphalaria adowensis (= Biomphalaria pfeifferi (Kraus, 1848)), leg. Courtois et Dr. Masse , 1952 (in Scacchitano 1952 as Glossiphonia disjuncta Moore, 1939); deposited at the Royal Museum of Central Africa in Tervuren ( Belgium), Coll. No. : 28950-28954

Type locality.

Democratic Republic of Congo, Ituri Province, Bunia, Jardin de Pères, near the border with Uganda at Lake Albert, leg. Courtois et Dr. Mass, 2nd March 1952 (in Sciacchitano 1952, 1954 as Glossiphonia disjuncta Moore, 1939)

Diagnosis.

Alboglossiphonia species up to 7.1 mm long and up to 3.1 mm wide; elongate oval with a strongly wavy to jagged body edge, outermost area hyaline; Head barely set off, but with a pronounced upper lip; cranial sucker small in front, round at the rear, channel-shaped towards the front (pear shaped), small pinprick-shaped mouth pore; flat caudal sucker small-medium, circular with thick walls and wide attachment point (<1/3 of the maximum body width); Base color unknown, definitely light; 30-36 thin longitudinal stripes (muscle strands); smooth surface, no prominent tubercles or papillae, but small sensory papillae, especially lateral; eye position typical of the genre, but with constant fusion of the first pair of eyes and the left and right eyes of the second and third pair, thus only three eyes visible; barely discernible gonopores spaced by two annuli; crop caeca 6, the first 5 simple to slightly bifurcated, 6th pair with 5 small side lobes; further internal anatomy unknown.

Description.

A total of 25 specimens were examined, of which all external characteristics were recorded. Regarding the internal anatomy, the crop caeca could only be examined in backlight.

Body form and size. The body is oblong oval with a length of 7.1 mm. The maximum width in the second half of the body is 3.1 mm. The dorsal side is slightly curved, the ventral side is flat. The head is only vaguely separated, the body tapers towards the tip of the body. There is a mouth lobe on the head, often visible as a narrow extension dorsally, similar to Alboglossiphonia heteroclita (Linnaeus, 1761). The rear edge is bluntly rounded. The side edges, which are wavy to jagged, are striking and typical of the species (Fig. 14 ).

Annulation. Circa 70 annuli were counted. The first six annuli are in the head area. All annuli have the same width value. In the area of the midbody, the three annuli per segment are clearly visible on the outer edge because they are separated by a deeper marginal furrow.

Suckers and mouth. The cranial sucker is small and pear-shaped (Figs 15 , 16 ) with a maximum width and length of 2.1 mm. However, only the rear part is slightly wider. The cranial sucker merges into a rather narrow furrow that runs on the underside of the mouth flap. The edge is thin. In the center of the flat cranial sucker is a small, pinprick-shaped but clear mouth opening. The caudal sucker is almost circular with a length of 0.59 mm and a width of 0.60 mm (max. 0.95 and 0.95 mm). The width of the caudal sucker is on average less than one third of the maximum body width. The caudal sucker, which is ventrally oriented and has a wide base, is flat with strong edges.

Colour and pattern The living animal is certain to have a light base color, probably light brown or yellowish. The ventral side is lighter. There are no spots or patterns. There are 30 to 36 thin stripes (muscle strands) recognizable as faint longitudinal lines, especially in the middle and rear part. The outer edge is a hyaline area that is more or less pronounced (Fig. 17 ).

Papillae and tubercles. The entire body is smooth. There are no warts or prominent papillae. Only tiny, evenly spaced, sensory papillae are visible at high magnification. At the margins, these papillae appear to be more concentrated where the hyaline outer lobes protrude.

Eyes. At first glance, the consistently three eyes are not typically formed for the genus Alboglossiphonia . In three of the 25 specimens available, it was evident that two eyes had fused together. These almost always result in circular structures. The original six eyes and their arrangement are therefore typical of the genus. The eyes do not differ in size. The first, medially fused, pair lies on annulus 4 and the longitudinally fused left and right eyes of the second and third pairs are found on annulus 5. As with all Alboglossiphonia species, there are variations in the arrangement (Fig. 18 ). Eye reductions are not recognizable.

Sciacchitano (1954) already pointed out the merging of the eyes (specimens No. 21-25), so that only three eyes can be seen instead of six (three pairs) of eyes. One specimen is even said to have a complete fusion of all six eyes, but this could not be confirmed in the present revision. Some specimens were curled and severely hardened so that the eyes were not visible.

Gonopores Both gonopores are very small and inconspicuous to almost invisible. Gonopores can only be seen in five specimens from a body length of 5.9 mm, mostly only very faintly. The distance between the male and female gonopore is two annuli. Sometimes the furrow between them also appears somewhat darker, giving the appearance of three gonopores. However, this remains unconfirmed.

Crop caeca. Crop caeca are only visible in a few animals (Fig. 14 ). There are 6 pairs of crop caeca. The first 5 are simple, of which the back ones often split in two in the last third. The edges appear wavy. The 6th pair of ventricles has 5 small side branches, which also have wavy borders.

Etymology.

The newly described species is named after the place where it was found. Bunia is the capital of Ituri Province in the Democratic Republic of the Congo.

Differential diagnosis.

The placement in the genus Alboglossiphonia results from the position of the eyes and the distance between the gonopores. Eleven species are known from Africa, and only six from south of the Sahara (including this one). All characteristics from Table 2 can be used for differentiation.

The gonopores of the species Alboglossiphonia buniana sp. nov. have a distance of 2 annuli, differing from A. conjugata (Oosthuizen, 1978) and A. disuqi El-Shimy, 1990, where the distance is only 1 annulus, and from A. hyalina , which has only one common gonopore. Alboglossiphonia conjugata and A. disuqi also have papillae and warts as well as rows of spots. The location of the gonopores is identical in the following species: Alboglossiphonia afroalpina sp. nov., A. disjuncta (Moore, 1939), A. iberica Jueg, 2008, A. levis Gouda, 2010, A. macrorhyncha (Oosthuizen, 1978), A. namaquaensis (Augener, 1936) and A. polypompholyx Oosthuizen, Hussein & El-Shimy, 1988. The presence of warts and prominent papillae clearly distinguish Alboglossiphonia disjuncta , A. macrorhyncha and A. polypompholyx from A. buniana sp. nov. An important diagnostic feature is the crop caeca, of which there are 6 pairs. Only Alboglossiphonia macrorhyncha , A. hyalina and A. disuqi have the same number. These species differ in the distances between the gonopores (see above). The number of crop caeca in Alboglossiphonia afroalpina is not known. However, this species clearly differs from all others in its distinctive spotting and body shape. Alboglossiphonia macrorhyncha is most similar to A. buniana sp. nov., however, the latter differs in the shape of the anterior sucker with mouth opening, the smooth body surface and especially the wavy to jagged hyaline outer edge. The pairs of eyes fused into three eyes with a round cross-section seem to be typical of Alboglossiphonia buniana . Fusions to form three eyes also occur regularly in Alboglossiphonia polypompholyx and A. levis , but not in a circle but rather as clusters of pigment ( Oosthuizen et al. 1988; El-Shimy 1994; Gouda 2010). However, the position of the eyes can also be variable.

Ecology.

Not much can be said about the ecology because no information other than the host animals was recorded when the specimens were collected in 1952. Alboglossiphonia buniana has been found feeding on Biomphalaria pfeifferi and Radix natalensis . Both snail species are widespread in Africa in standing and slow-flowing waters. Radix natalensis prefers flat riparian areas with different substrates (e.g. submerged vegetation, rocks, mud).

Distribution.

Alboglossiphonia buniana sp. nov. is only known from Bunia, the capital of Ituri Province in the Democratic Republic of Congo. On the labels of the two tubes in the Central Africa Museum in Tervuren (Belgium) and in Sciacchitano (1952, 1954) there are no more detailed place names, except for Jardin de Pères ('Garden of the Fathers'; Sciacchitano 1952). It could be the park at a church or school (oral communication C. Allard, Tervuren). Bunia is located at about 1,250 m above sea level on the edge of the Blue Mountains (with elevations of up to 2,000 m above sea level) immediately west of Lake Albert on the border with Uganda. Several small rivers flow through Bunia, emptying into the Aruwimi, which in turn drains into the Congo.

Figures

Figure 14. Alboglossiphonia buniana sp. nov., habitus with jagged body edge and visible crop caeca, Paratype 16, Coll. - Nr. RMCA _ VERMES _ 43677, Photo: M. Jueg.

Figure 15. Alboglossiphonia buniana sp. nov., cranial sucker with mouth pore.

Figure 16. Alboglossiphonia buniana sp. nov., cranial sucker, Holotype, RMCA _ VERMES _ 43662, Photo: A. Henrard.

Figure 17. Alboglossiphonia buniana sp. nov., dorsal.

Figure 18. Eye positions of Alboglossiphonia buniana sp. nov., individual numbering corresponds to Table 2.