Eupolybothrus (Schizopolybothrus), Verhoeff, 1934

C. A. W. Jeekel, 1967, On two Italian Lithobius species described by Silvestri, with taxonomic notes on the genus Eupolybothrus Verhoeff (Chilopoda, Lithobiida), BEAUFORTIA SERIES OF MISCELLANEOUS PUBLICATIONS 14, No. 175, pp. 165-175 : 170-172

Subgenus Schizopolybothrus Verhoeff, 1934

This subgenus was monotypically based on E. caesar (Verhoeff, 1899) , to which later E. tabularum (Verhoeff, 1937) was added. In the present concept Schizopolybothrus comprises over a dozen of forms occurring in North Italy, Jugoslavia, Albania, and Greece. Apparently the species of this subgenus are rare, and most of the described forms are known only from the original material.

The characters of the subgenus are the presence of triangular projections on the 9th, 11th and 13th tergites, and a VCm spine on the 15th leg. The 15th leg has one to four VCa spines, and a single claw. 14th leg with one to three VCa spines.

According to the structure of the last two pairs of legs of the male and the male gonopods, the species can be divided into three categories.

I. The 15th leg with a large rounded knob proximad of the middle of the caudal side of the prefemur. The prefemur of the 14th leg often has a triangular process distally on the dorso-caudal side. Gonopods short.

To this group belong E. caesar (Verhoeff, 1899) , E. caesar ssp. valonensis (Verhoeff, 1905) , E. caesar ssp. patens (Attems, 1935) , E. spiniger (Latzel, 1888) , E. acherontis (Verhoeff, 1900) (probably, although only the female has been described), E. acherontis ssp. wardaranus (Verhoeff, 1937) , E. stygis (Folkmanova, 1940) , and E. leostygis (Verhoeff, 1899) . Its known distribution includes Jugoslavia (Bosnia, Hercegovina, Dalmatia, Macedonia), Albania, and Greece (Corfu, Epirus). E. stygis and E. leostygis were originally described from caves.

II. The 14th and 15th legs without special modifications. Gonopods short.

Here belong E. tabularum (Verhoeff, 1937) , and probably also E. excellens (Silvestri, 1894) , although the male characters of the latter are unknown. The two species were described from northwestern Italy (Prov. Cuneo, Prov. Genova), E. excellens from caves.

III. Prefemur of the 15th leg with a deep dorsal furrow. Gonopods long.

The two known species, E. zeus (Verhoeff, 1901) and E. sissii (Kanellis, 1959) , were described from Central Greece and Euboea, respectively.

The characters by which the species and subspecies within these three categories are separated concern mainly differences in the numbers of ocelli, antennomeres and coxosternal teeth, and the spinulation of the legs. Their significance in many cases seems dubious, and it is very likely that the groups II and III actually concern only one species each. One may even wonder if not the so-called species and subspecies of group I are just elements of one single polytypic species. Probably the cave-dwelling specimens, with their more elevated number of antennomeres and sometimes reduced number of ocelli, do not represent one or more different troglobiont species, but are merely the cave forms of one troglophilous species. Given the usual instability of the mentioned characters in Eupolybothrus , the influence of cave life oh the ontogenetic development might well result here in a considerable amount of variability.

Considering the above, it is clear that the following key to the species of Schizopolybothrus can be regarded only as a guide to the published descriptions and not as an identification key in the usual sense.

KEY TO THE SPECIES AND SUBSPECIES OF SCHIZOPOLYBOTHRUS VERHOEFF

1. Antennae composed of 61 to 83 a ntennomeres... 2

- Antennae composed of 38 to 58 anten nomeres... 6

2. Eyes consisting of 2 to 5 (10) ocelli. 73 to 80 a ntennomeres. 7 + 7 to 11 + 11 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3-4, 2-3, 1-2; 2 or 3 VCa spines... E. leoslygis (Verh.)

- Eyes consisting of 13 to 23 ocelli... 3

3. 74 to 83 antennomeres. 15th leg with 2 to 4 VCa spines, in the male with a large prefemoral knob. Jugoslavian species... 4

- 61 to 76 antennomeres. 15th leg with 1 or 2 VCa spines, in the male without modifications. Italian species... 5

4. 15 ocelli. 74 antennomeres. 9 + 9 coxosterna 1 teeth. Ventral spinulation of 14th leg: 1, 1, 3, 2, 1; 2 VCa spines. 15th leg with 3 VCa spines... E. acherontis (Verh.)

- 18 to 20 ocelli, 81 to 83 antennomeres. 8 + 8 or 9 + 9 coxosternal teeth. Ventral spinulation of 14th leg: 1, 1, 3, 2, 2; 3 VCa spines. Ventral spinulation of 15th leg: 1, 1, 3, 2, 2; 3 tot 4VCa spines... E. acherontis ssp. wardaranus (Verh.)

- 19 ocelli. 83 antennomeres. 10 + 11 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 2, 1; 2 VCa spines... E. stygis (Folkm.)

5. 18 to 20 ocelli. 61 to 76 antennomeres. 7 + 7 to 8 + 8 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 3, 2; 1 or 2VCa spines... E. excellens (Silv.)

- 20 ocelli. 65 to 67 antennomeres. 9 + 9 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 2, 1-2; 1 or 2 VCa spines... E. tabellamm (Verh.)

6. 38 to 50 antennomeres. 15th leg with 1 VCa spine, in the male with a dorsal prefemoral furrow... 7

- 50 to 58 antennomeres. 15th leg with 2 to 4 VCa spines, in the male with a large prefemoral knob... 8

7. 19 to 20 ocelli. 41 to 50 antennomeres. 7 + 7 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 2, 1... E. zeus (Verh.)

- 38 antennomeres. 8 + 8 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 2, 2... E. sissii (Kanelis)

8. 16 to 19 ocelli. 50 to 56 antennomeres. 7 + 7 to 11 + 11 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 4, 2, 0-1; 3 VCa spines... E. spinirger (Latz.)

- 13 ocelli. 54-57 antennomeres: 6 + 6 to 8 + 9 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 2, 0; 2 or 3 VCa spines... E. caesar (Verh.)

- 19 ocelli. About 50 antennomeres. 8 + 8 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1. 3, 2, 1; 3 VCa spines... E. caesar ssp. valonensis (Verh.)

- 23 ocelli. 58 antennomeres. 9 + 9 coxosternal teeth. Ventral spinulation of 15th leg: 1, 1, 3, 2, 2; 2 or 3 VCa spines... E. caesar ssp. patens (Att.)

In connection with the species of Schizopolybothrus the following remarks must be made.

Verhoeff (1943) referred leostygis to his subgenus Mesobothrus , thus plying that the species has long gonopods. As this is contradictory to his own and to Attems's (1935) descriptions, and as leostygis through other characters shows strong affinities to acherontis and caesar , we may safely assume that this was an error. Verhoeff (1943) distinguished a subspecies stygisleo of E. leostygis which was characterized by having 2 ocelli (instead of 4 to 5) and by having the ten distal antennomeres 1 1/3 to 1 1/2 times longer than broad and the last antennomere 1 3/4 times longer than broad. Considering the instability of this kind of characters in the Lithobiidae this subspecies is better withdrawn. The characters in the above key were derived from the descriptions and notes on leostygis and stygisleo by Verhoeff (1899, 1900, 1943) and Attems (1935). According to Attems the species has up to 10 ocelli.

The record of leostygis by Attems (1908) was based on a misidentification and refers to E. obrovensis (Verhoeff, 1930) .

It is not clear why Attems (1935) referred his subspecies patens to leostygis . In view of the high number of ocelli and the considerably lower number of antennomeres, this form has comparatively little to do with leostygis and is better associated with caesar .

E. excellens seems very closely related to tabularum , but unfortunately the discovery of the male has to be awaited before a more definite statement can be made. Moreover, tabularum is characterized by a dense brush of setae covering partly the coxosternal teeth. This brush is lacking completely in excellens .