Research Article |
Corresponding author: Didier Vanden Spiegel ( dvdspiegel@africamuseum.be ) Academic editor: Robert Mesibov
© 2014 Didier Vanden Spiegel, Sergei Golovatch.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Vanden Spiegel D, Golovatch S (2014) The millipede genus Eviulisoma Silvestri, 1910 in Kenya, with descriptions of new species (Diplopoda, Polydesmida, Paradoxosomatidae). ZooKeys 459: 1-24. https://doi.org/10.3897/zookeys.459.8621
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The genus Eviulisoma, the largest among Afrotropical Paradoxosomatidae, currently encompasses 36 species or subspecies, including six new from Kenya: E. ngaia sp. n., E. ngaiaorum sp. n., E. taitaorum sp. n., E. taita sp. n., E. kirimeri sp. n. and E. kakamega sp. n. In addition, E. alluaudi Brolemann, 1920 and E. silvestre (Carl, 1909) are recorded for the first time beyond their type localities in Kenya and Tanzania, respectively, based on new material from Kenya. A key is given to all ten species of the genus presently reported from Kenya.
Diplopoda , Eviulisoma , taxonomy, new species, key
The genus Eviulisoma Silvestri, 1910 is the largest among Afrotropical Paradoxosomatidae, currently known to encompass 30 species or subspecies in central and eastern Africa (
The following checklist of Eviulisoma species or subspecies has been extracted from
1. E. cavallii (Silvestri, 1907), the type species, from Uganda and Rwanda;
2. E. alluaudi Brolemann, 1920, from Kenya;
3. E. boranicum Manfredi, 1939, from Ethiopia;
4. E. castaneum Attems, 1953, from the Democratic Republic of the Congo;
5. E. cervicorne (Attems, 1927), from an unknown locality in Africa;
6. E. congicolens (Chamberlin, 1927), from the Democratic Republic of the Congo;
7. E. cylindricum Attems, 1953, from the Democratic Republic of the Congo;
8. E. cylindricum simile Attems, 1953, from the Democratic Republic of the Congo;
9. E. dabagaense Kraus, 1958, from Tanzania;
10. E. debile Attems, 1938, from the Democratic Republic of the Congo;
11. E. egregium Attems, 1938, from the Democratic Republic of the Congo;
12. E. fossiger (Carl, 1909), from Tanzania;
13. E. graueri Attems, 1944, from the Democratic Republic of the Congo;
14. E. insulare Brolemann, 1920, from Zanzibar Island, Tanzania;
15. E. iugans (Chamberlin, 1927), from the Democratic Republic of the Congo;
16. E. iuloideum (Verhoeff, 1941), from Tanzania;
17. E. jeanneli Brolemann, 1920, from Kenya;
18. E. kwabuniense Kraus, 1958, from Tanzania;
19. E. lanceolatum Attems, 1953, from the Democratic Republic of the Congo;
20. E. muturanum Attems, 1937, from both the Democratic Republic of the Congo and the Republic of the Congo (Brazzaville);
21. E. obesum Attems, 1953, from the Democratic Republic of the Congo;
22. E. obscurum Attems, 1937, from the Democratic Republic of the Congo;
23. E. pallidum Attems, 1939, from Kenya;
24. E. schoutedeni (Attems, 1929), from the Democratic Republic of the Congo;
25. E. silvaticum Attems, 1953, from Rwanda;
26. E. silvestre (Carl, 1909), from Tanzania;
27. E. somaliense Ceuca, 1971, from Somalia;
28. E. tertalinus Manfredi, 1941, from Ethiopia;
29. E. tritonium Attems, 1937, from the Democratic Republic of the Congo;
30. E. ussuwiense (Carl, 1909), from Tanzania.
Prompted by the discovery of several new or poorly-known congeners in Kenya, eastern Africa, this paper focuses on their descriptions or records, as well as presenting a key to all Eviulisoma species currently known to occur in Kenya.
The material underlying the present contribution was taken in Kenya in 1999–2004. Most of the types are housed in the collection of the Royal Museum for Central Africa, Tervuren, Belgium (MRAC), a few paratypes have been donated to the Zoological Museum, Moscow State University, Moscow, Russia (ZMUM + entry number).
SEM micrographs were taken using a JEOL JSM-6480LV scanning electron microscope. After examination, SEM material was removed from stubs and returned to alcohol, all such samples being kept in MRAC.
Line drawings were very skillfully executed by Mrs Nadine Van Noppen (MRAC).
Holotype ♂ (MRAC 20799), Kenya, Ngaia Forest, N00°19', E38°02', ca 1070 m a.s.l., 2.XII.2002, leg. D. VandenSpiegel.
Paratypes: 3 ♂, 1 ♀, 1 juv. (MRAC 22634), 1 ♂ (ZMUM ρ2442), same data, together with holotype; 1 ♂ (MRAC 20703), same data, 3.XII.2002, leg. D. VandenSpiegel.
To emphasize the type locality, a noun in apposition.
Differs from all congeners but E. ngaiaorum sp. n. in the absence of a sternal excavation in ♂ segment 6, from E. ngaiaorum sp. n. in the absence of sternal cones in the ♂ and by the presence of a well-developed, phylloid, postfemoral process of the gonopod (Fig.
Length of holotype ca 16 (♂), of adult paratype ca 18 mm (♀), width of midbody metazonae 1.5–1.6 (♂) or 2.0 mm (♀). Coloration uniformly yellowish, often with an annulated pattern of slightly more intense yellowish to marbled reddish yellow metazonae. Legs usually slightly lighter to nearly pallid.
Body subcylindrical, metazonae only faintly vaulted laterally compared to prozonae (Fig.
Sternites generally without modifications, densely setose, cross-impressions evident, but axial impressions especially weak; a subquadrate, densely setose lobe between ♂ coxae 4 (Fig.
Gonopods (Fig.
Vulvae densely setose, without peculiarities, as in Fig.
Due to flattened, not deeply excavate, sterna between ♂ coxae 6 and 7, this species resembles Eoseviulisoma Brolemann, 1920, but the presence of a central lobe between ♂ coxae 4 warrants the assignment of this species to Eviulisoma.
«Sous-genre Eviulisoma, s. str. — Un prolongement entre les pattes de la 4e paire. Une excavation sternale accentuée au 6e segment. — Tronc du télopodite des gonopodes plus court que les rameaux. Suture transverse des métazonites lisse. — Type: E. Cavalli Silv.
Sous-genre Eoseviulisoma, nov. — Pas de prolongement entre les pattes de la 4e paire. — Excavation sternale du 6e segment très faible. — Tronc du télopodite des gonopodes plus long que les rameaux. — Suture transverse des métazonites perlée. — Type: E. julinum Att.»
Distribution of Eviulisoma species in Kenya: E. taitaorum sp. n. (A), E. taita sp. n. (B), E. ngaiaorum sp. n. (C), E. ngaia sp. n. (D), E. kirimeri sp. n. (E), E. alluaudi Brolemann, 1920 (F), E. jeanneli Brolemann, 1920 (G), E. pallidum Attems, 1939 (H), E. kakamega sp. n. (I), E. silvestre (Carl, 1909) (J).
Holotype ♂ (MRAC 20806), Kenya, Ngaia Forest, N00°19', E38°02', ca 1070 m a.s.l., 3.XII.2002, leg. D. VandenSpiegel.
Paratypes: 1 ♂ fragment, 1 ♂ subadult, 8 juv. (MRAC 20806), same data, together with holotype.
To emphasize the type locality, in Latin meaning “a dweller of Ngaia”.
Differs from all congeners but E. ngaia sp. n. in the absence of a sternal excavation in ♂ body segment 6, from E. ngaia sp. n. in the presence of sternal cones in the ♂ and only a vestigial gonopod postfemoral process (Fig.
Length of adults ca 20 mm (♂ holotype), width of midbody metazonae 2.2 mm (both ♂ holotype and ♂ fragment paratype). Juveniles entirely pallid.
Coloration and other adult characters as in E. ngaia sp. n., except as follows.
Transverse metatergal sulcus/line wanting. Tergal setae mostly retained, pattern 3+3 (Fig.
Sternites behind gonopods with a distinct sharp cone near each ♂ coxa, each caudal pair per diplosegment being a little stronger than anterior one. Setose lobe between ♂ coxae 4 (Fig.
Gonopods (Fig.
Eviulisoma ngaiaorum sp. n., ♂ holotype (A–C) & ♂ paratype (D, E). A anterior part of body, lateral view B posterior part of body, lateral view C body segments 5–7, ventral view D, E right gonopod, ventral and mesal views, respectively. Scale bars: 0.1 mm (D, E); A–C, drawn not to scale. Designations in text.
Holotype ♂ (MRAC 22630), Kenya, Taita Hills, Chawia Forest, 1500 m a.s.l., S03°29', E38°20', pitfall trapping, 1–20.VI.1999, leg. R. Mwakos.
Paratypes: 3 ♂, 1 ♀, 8 juv. (MRAC 18071), same data, together with holotype; 3 ♂ (MRAC 18016), same locality, 1500 m a.s.l., pitfall traps, 10–26.VI.1999, leg. R. Mwakos; 3 ♀ (MRAC 18096), same locality, 1500 m a.s.l., pitfall traps, III–IV.1999, leg. L. Rogo; 1 ♀, 3 juv. (MRAC 17993), same locality, 1500 m a.s.l., III–IV.1999, leg. D. VandenSpiegel; 3 juv. (MRAC 18505), same locality, Winkler extraction, 7.XII.1999, leg. D. VandenSpiegel & J. P. Michiels; 1 ♂, 2 ♀, 5 juv. (MRAC 18424), same locality, 7.XII.1999, leg. D. VandenSpiegel & J. P. Michiels; 1 ♂ fragment, 1 ♀, 2 juv. (MRAC 18043), 1 ♂, 1 ♀ (ZMUM ρ2443), Taita Hills, Ngangao Forest, S03°22', E38°21', 1820 m a.s.l., 17.VIII.1999, leg. R. Mwakos; 1 ♂ fragment, 20 ♀ (MRAC 18476), same locality, 4.XII.1999, leg. D. VandenSpiegel & J. P. Michiels; 3 ♀, 3 juv. (MRAC 18008), same locality, 1820 m a.s.l., 19.VI.1999, leg. D. VandenSpiegel; 1 ♀ (MRAC 18090), same locality, 1820 m a.s.l., pitfall traps, III–IV.1999, leg. D. VandenSpiegel, 1 ♂ (MRAC 18036), same locality, 1820 m a.s.l., pitfall traps, 15–17.III.1999, leg. L. Rogo; 1 ♂ (MRAC 22622), Taita Hills, Fururu Forest, S3°26', E38°20', 9.XII.1999, leg. D. VandenSpiegel & J. P. Michiels; 1 ♂, 1 ♀, 7 juv. (MRAC 22623), same locality, pitfall traps, 14–17.XII.2004, leg. A. Bwong, J. Mwandoe & J. Measey; 1 ♂, 1 ♀, 3 juv. (MRAC 18083), Taita Hills, Vuria Forest, S03°24', E38°17', 2200 m a.s.l., 26.VI.1999, leg. D. VandenSpiegel; 1 ♀ (MRAC 18459), Taita Hills, Sagala Forest, S03°50', E38°58', 5.XII. 1999, leg. D. VandenSpiegel & J. P. Michiels.
Non-types: ca 30 juv. (MRAC 18.543), Taita Hills, Fururu Forest, S03°26', E38°20', Winkler extraction, 9.XII.1999; 1 ♀ (MRAC 18441), Taita Hills, Wundanyi, near house, S03°24'07", E38°21'49", 6.XII. 1999, all leg. D. VandenSpiegel & J. P. Michiels.
To emphasize the type locality, in Latin meaning “a dweller of Taita”.
Differs from all congeners in the remarkable size dimorphism, coupled with absence of a sternal lobe between ♂ coxae 4, as well as the subequally long and slender solenophore (sph) and postfemoral process (p) (Figs
Length of adults ca 17–20 (♂ holotype and some ♂ & ♀ paratypes from Chawia, Fururu and from Ngangao) or 28–38 mm (most of ♂ & ♀ paratypes from Fururu and Ngangao, all few paratypes from Sagala and Vuria), width of midbody metazonae 1.7–1.8 (♂ holotype and some ♂ paratypes) up to 2.0 mm (♀ paratypes from Chawia) or 2.5–2.6 (most of ♂ paratypes from Fururu and Ngangao) up to 3.0–3.8 mm (most of ♀ paratypes from Fururu and Ngangao).
Coloration from pallid, via light pinkish or marbled pinkish brown to nearly chocolate brown, pattern often annulated due to darker metazonae, including later instars of larger morph. Legs pallid to yellowish, earlier instars always entirely pallid. Sometimes a narrow, darker, pigmented axial line and a similar transverse line in caudal 1/3 of metaterga.
All characters as in E. ngaia sp. n. (Fig.
Surface rather smooth and shining (Figs
Gonopods (Figs
Vulvae without peculiarities, as in Fig.
This new species seems remarkable in being represented by two different size morphs which invariably co-occur at least in sufficiently rich samples and show no intermediates. Thus, in one sample from Chawia the adult ♂♂ can vary in size by 1.5–2.0 times. Larger animals tend to be darker than smaller ones.
Such a strong size morphism could be advantageous for the local populations in variably adverse ecological conditions, possibly allowing selection for different life strategies.
The above two species from Taita Hills show parapatry (Map
In addition, the absence of a central lobe between ♂ coxae 4 is rather characteristic of Eoseviulisoma Brolemann, 1920, but the smooth metazonital suture, the structure of the gonopods and the deeply excavate sterna between ♂ coxae 6 and 7 warrant the assignment of this species to Eviulisoma (cf.
Eviulisoma taitaorum sp. n., ♂ (A, D–L) & ♀ paratypes (B, C, M, N). A habitus, lateral view B midbody legs, lateral view C ozopore, lateral view D ventral brushes on tibia and tarsus, ventral view E, F modified setae of ventral brushes, ventral view G antennomeres 6–8, sublateral view H anterior part of body, ventral view I both gonopods in situ, ventral view J, L right gonopod, mesal and submesal views, respectively K gonopod tip, sublateral view M both vulvae in situ, ventrocaudal view N right vulva, ventrocaudal view. Scale bars: 1.0 (A), 0.5 (B, H, M), 0.2 (I, J, L), 0.1 (C, D, G, K, N) & 0.01 mm (E, F). Designations in text.
Holotype ♂ (MRAC 22631), Kenya, Taita Hills, Mbololo Forest, S03°22.56', E38°20.70', 1800–1900 m a.s.l., pitfall traps, III–IV.1999, leg. L. Rogo.
Paratypes: 17 ♂, 13 ♀, 4 juv. (MRAC 18084), 1 ♂, 1 ♀ (ZMUM ρ2444), same data, together with holotype; 2 ♂, 2 ♀ (MRAC 18029), same locality, pitfall traps, 3.VII-2.VIII.1999, leg. R. Mwakos; 1 ♂, 1 ♀ (MRAC 18412), same locality, 8.XII.1999, leg. D. VandenSpiegel & J. P. Michiels; 1 ♀, 1 juv. (MRAC 17990), same locality, 22.VI.1999, leg. D. VandenSpiegel; 9 ♂, 8 ♀, 33 juv. (MRAC 18039), same locality, 1800–1900 m a.s.l., sieving, 2–10.VII.1999, leg. R. Mwakos; 1 ♀ (MRAC 17976), same locality, 21.VI.1999, leg. D. VandenSpiegel; 1 ♂, 1 ♂ fragment, 1 ♀, 1 ♀ fragment (MRAC 18414), same locality, 8.XII.1999, leg. D. VandenSpiegel & J. P. Michiels; 3 ♂, 1 ♀ (MRAC 18100), Taita Hills, Yale Forest, 1840 m, S03°39', E38°33', pitfall traps, III–IV.1999, leg. L. Rogo; 4 ♂, 4 ♀, 22 juv. (MRAC 18451), Taita Hills, Fururu Forest, S03°26', E38°20', 9.XII.1999; 1 ♂, 3 ♀, 20 juv. (MRAC 18495), same locality, Winkler extraction, 9.12.1999; 5 ♂, 4 ♀, 1 juv. (MRAC 18576), Taita Hills, Mwachora Forest, Winkler extraction, 10.XII.1999, all leg. D. VandenSpiegel & J. P. Michiels; 2 ♂ (MRAC 22632), same data; 1 ♂, 1 ♀, 1 ♀ fragment, 1 juv. (MRAC 22633), same locality, 15.II.2004, leg. T. Spanhove & M. Chovu.
To emphasize the type locality, a noun in apposition.
Differs from congeners by a broadly and regularly rounded hypoproct, coupled with the presence of sternal cones behind ♂ body segment 7, and the lamellar, slender, apically unciform and bidentate solenophore (sph) carrying a lateral tooth midway (t) and reaching about as long as a flagelliform solenomere (sl), both sph and sl being considerably higher than a rather simple, similarly slender, postfemoral process (p). See also Key below.
Length of adults ca 16–23 (♂) or 18–28 mm (♀), width of midbody metazonae 1.5–2.7 (♂) or 2.0–3.7 mm (♀). Holotype ca 16 mm long and 1.6 mm wide on midbody metazonae.
Coloration from pallid to annulated chocolate brown due to darker metazonae, often with a thin axial pigment line and a similar transverse pigment line in posterior 1/3 of metaterga.
Other adult characters as in E. ngaia sp. n., except as follows.
Vertigial region with a few setae (Figs
Setose lobe between ♂ coxae 4 (Fig.
Gonopods (Figs
Vulvae without peculiarities, as in Fig.
Eviulisoma taita sp. n., ♀ (A, B) & ♂ (C–J) paratypes. A, D anterior part of body, ventrocaudal and ventral views, respectively B right vulva, ventrocaudal view C distal part of a midbody leg, lateral view E sterna between coxae 4–7, ventral view F same, but with left gonopod placed into sternal pocket-shaped excavation G both gonopods in situ, ventral view H, J left gonopod, mesal and lateral views, respectively I tips of both gonopods in situ, ventral view. Scale bars: 0.5 (A, C, D), 0.2 (G), 0.1 (E, F, H, J) & 0.05 mm (B, I). Designations in text.
Holotype ♂ (MRAC 22624), Kenya, Kirimeri Forest near Runyenyere, S00°25', E37°33', 1700 m a.s.l., sieved litter, 27.IV.2004, leg. D. VandenSpiegel, R. Jocqué & C. Warui.
Paratype: 1 ♂ (MRAC 22625), same data, together with holotype.
To emphasize the type locality, a noun in apposition.
Differs from congeners in the epiproct showing two distinct apical claws directed ventrad (Fig.
Length of ca 15–16 mm, width of midbody metazonae 1.5 (♂ holotype) or 1.7 mm (♂ paratype). Coloration entirely pallid.
Other adult characters as in E. ngaia sp. n., except as follows.
Clypeolabral region rather sparsely setose (Fig.
Setose lobe between ♂ coxae 4 (Fig.
Gonopods (Fig.
Eviulisoma kirimeri sp. n., ♂ paratype. A anterior part of body, lateral view B posterior part of body, lateral view C body segments 5–7, ventral view D–F left (D, F) and right (E) gonopod, ventral, mesal and anteroventral views, respectively. Scale bars: 0.2 (E) & 0.1 mm (D, F); A–C, drawn not to scale. Designations in text.
Holotype ♂ (incomplete, only head and first 13 segments present) (MRAC 20771), Kenya, Likhanda Hills, Kakamega Forest, S00°13', E34°54', pitfall traps, 5.II.2002, leg. D. S. Smith.
Paratypes: 1 ♂ (incomplete, lacking gonopods and five posteriormost segments), 4 ♀, 5 juv., 1 fragment (MRAC 20772), same data, together with holotype.
To emphasize the type locality, a noun in apposition.
Differs from congeners by the gonopod solenophore (sph) being complex, cup-shaped, lamellar, about as long as a flagelliform solenomere (sl), flanked medially by a long, subspiniform, postfemoral process (p) (Figs
Length of ♀ ca 22–23 mm, width of midbody metazonae 2.1 (♂ holotype), 2.7 (♂ paratype) or 3.1–3.3 mm. Coloration uniformly light pinkish yellow, legs lighter yellow.
Other adult characters as in E. ngaia sp. n., except as follows.
Vertigial region with a few setae (Figs
Setose lobe between ♂ coxae 4 (Figs
Gonopods (Figs
Eviulisoma kakamega sp. n., ♂ paratype. A anterior part of body, ventral view B ventral brushes on tibia and tarsus, lateral view C body segments 2–7, ventral view D, E right gonopod, ventral and lateral views, respectively. Scale bars: 0.5 (A, C), 0.2 (D, E) & 0.1 mm (B). Designations in text.
3 ♂, 16 ♀, 4 juv. (MRAC 22626), 1 ♂, 1 ♀ (ZMUM ρ2445), Kenya, Chogoria Forest, S0°11'13", E37°28'07", 2658 m a.s.l., bamboo forest, sieved litter and beaten from bamboos, 24.IV.2004, leg. D. VandenSpiegel, R. Jocqué & C. Warui.
The above is only the second record of this species beyond the type locality: alpine meadows and a forest at 3100 m and 2600 m a.s.l., respectively, on Mt. Kinangop, S00°11', E37°28', Aberdare Ridge, Kenya (
1 ♂, 1 ♂ (incomplete, only last 8 segments present) (MRAC 22627), Kenya, Likhanda Hills, Kakamega Forest, S00°13', E34°54', pitfall traps, 28.IX.2002; 1 ♂ (incomplete, only segments 8–20 present) (MRAC 22628), same locality, pitfall traps, 6.IV.2002; 1 ♂ (MRAC 22629), same locality, pitfall traps, 6.VII.2002, all leg. D. S. Smith.
This is only the second record of this species which has hitherto been known solely from Bakoba, S00°11', E37°28', Tanzania (
Eviulisoma silvestre (Carl, 1909), ♂ from Kakamega Forest, Kenya. A head, frontal view B antenna, frontal view C ventral brushes on tibia and tarsus, ventral view D body segments 4–7, ventral view E, F right gonopod, ventral and mesal views, respectively. Scale bars: 0.5 (A, B, D, F), 0.2 (E) & 0.1 mm (C). Designations in text.
1 | Sterna between ♂ legs 6 and 7 flattened, not excavate (Figs |
2 |
– | Sterna between ♂ legs 6 and 7 deeply excavate and ledge-shaped for accommodation of gonopod tips (Figs |
4 |
2 | Sternal cones absent. Sternal lobe between ♂ coxae 4 large (Fig. |
E. ngaia sp. n. |
– | Sternal cones present, starting from ♂ body segment 8. Sternal lobe between ♂ coxae 4 rather small, slightly concave (Fig. |
E. ngaiaorum sp. n. |
3 | All ♂ telopodite segments distal to coxa or prefemur with ventral brushes. Epiproct with two distinct apical claws directed ventrad (Fig. |
E. kirimeri sp. n. |
– | Only 2–3 last telopodite segments distal to coxa or prefemur in ♂ with ventral brushes. Epiproct with only inconspicuous apical papillae. Gonopods either held parallel to each other or somewhat convergent, always compact | 4 |
4 | Paraterga 2 wanting | 5 |
– | Paraterga 2 at least traceable | 7 |
5 | Sternal cones totally absent. Hypoproct acute caudally. Gonopod postfemoral process longest, erect, digitiform, fringed at base on mesal face; both solenophore and solenomere only a little shorter, subequal in length, distal 1/3 of solenophore a subflagelliform branch | E. pallidum |
– | Sternal cones present at least between each caudal leg-pair per ♂ diplosegment following 7th. Hypoproct rounded caudally. Gonopod structure different, postfemoral process much longer than a similarly spiniform solenophore showing a fold for sheathing a likewise long solenomere in distal 1/3 extent | 6 |
6 | Sternal cones present only between each caudal leg-pair per ♂ diplosegment following 7th. Gonopod postfemoral process simple, not grooved longitudinally | E. jeanneli |
– | Sternal cones small, but present between both leg-pairs per ♂ diplosegment following 7th. Gonopod postfemoral process (p) more complex, grooved longitudinally, with a dorsal spinule in distal half (Fig. |
E. alluaudi |
7 | Sternal lobe between ♂ coxae 4 missing (Fig. |
E. taitaorum sp. n. |
– | Sternal lobe between ♂ coxae 4 usually present. Gonopods different. No distinct size morphs noted even in the syntopically occurring congener, E. taita sp. n. | 8 |
8 | Hypoproct trapeziform, with a sharp tooth caudally. Sternal lobe between ♂ coxae 4 very small to missing. Sternal cones behind body segment 7 absent. Gonopod postfemoral process long and subspiniform, nearly as long as solenomere and a lamellar, fold-shaped solenophore, the latter showing a parabasal, unciform process about half as long as postfemoral process | E. silvestre |
– | Hypoproct broadly and regularly rounded caudally. Sternal lobe between ♂ coxae 4 always quite conspicuous. Sternal cones behind ♂ body segment 7 present. Gonopods different | 9 |
9 | Gonopods (Figs |
E. taita sp. n. |
– | Gonopod solenophore (sph) complex, cup-shaped, lamellar, about as long as a flagelliform solenomere (sl), flanked medially by a long, subspiniform, postfemoral process (p) (Figs |
E. kakamega sp. n. |
At least in Kenya, several places appear to support two Eviulisoma species, e.g. Ngaia Forest, Taita Hills and Kakamega Forest. Furthermore, one of the species from Taita Hills demonstrates remarkable size dimorphism, when adult males can vary in size by 1.5–2.0 times, and is parapatric with a second Eviulisoma species. We are not aware of anything similar among other Paradoxosomatidae, but some Odontopygidae, a purely Afrotropical family of Spirostreptida, also show surprisingly distinct size dimorphism (Didier VandenSpiegel, unpublished results). As noted above, this variability may be advantageous for the local populations in adverse ecological conditions, possibly allowing for selection of different life strategies.
Last but not least, even though Eviulisoma is already the largest paradoxosomatid genus in tropical Africa, at the moment counting 36 species or subspecies, there is little doubt that numerous further species will be discovered in the region.
We are most grateful to all collectors who entrusted us their valuable material for treatment. Didier VandenSpiegel’s research visit to the Natural History Museum Vienna in 2005 to check the type material of Eviulisoma available there was partly financed by that museum. Sergei I. Golovatch is most obliged to the Musée Royal de l’Afrique Centrale, Tervuren for the invitation to work on this project.