Breeding of Kyklioacalles euphorbiophilus Stüben 2003
(Coleoptera: Curculionidae: Cryptorhynchinae)
by
Peter Stüben, Mönchengladbach
with 20 figures and 1 video [Med.Eup]

Abstract
Kyklioacalles euphorbiophilus Stüben 2003 from High Atlas, Morocco, is bred from dying parts of its host-plant, Euphorbia nicaeensis All. Taking as a starting-point habitat requirements at the ‘locus typicus’, the biotic and abiotic environmental conditions and methods of this successful breeding are presented here. All phases of development and breeding are demonstrated by 20 figures and 1 video sequence. Finally, recommendations for further breeding of flightless Cryptorhynchinae are given.
Keywords
Coleoptera, Curculionidae, Cryptorhynchinae, Kyklioacalles euphorbiophilus, breeding, host-plant, Euphorbia nicaeensis, Morocco.  
Introduction
During the work on my first description of Kyklioacalles euphorbiophilus in the beginning of 2003 [Stüben 2003a: 134-138], I was successful in breeding this endemic species from the Moroccan High Atlas.
Kyklioacalles euphorbiophilus [Fig. 175.1] is closely related to Kyklioacalles apogeus (Peyerimhoff 1925) [Fig. 176.1] [Fig. 178.6] from High Atlas near Tachedirt (‘Tizi-n-Tachedirt’, 3230 m), fallen into oblivion since then. The ‘locus typicus’ of Kyklioacalles euphorbiophilus - separated by large mountain massifs - is situated about 60 km south-westerly on the northern face of the ‘Tizi-n-Test’ (2000 m) [Fig. 175.20]. The species is strictly bound to Euphorbia nicaeensis All. and lives on steep slopes of maximum 1-2 hectars. This extremely unusual situation just even produced the assumption that this big Kyklioacalles species from the Kyklioacalles teter-/barbarus-group could be a new species (see 'bionomy'). Reproductive isolation after separation by huge mountain massifs and subsequent specialisation to a - here also very isolated growing - host-plant really seem to be important factors in species separation.
At first there was big scepticism, that breeding could be successful. Should it be possible, in view of the specific biotic and abiotic conditions and a very narrow ‘ecological niche’, that there is really a chance to breed Kyklioacalles euphorbiophilus from Euphorbia nicaeensis in an artificial environment? Was it the right point in time - beginning of January -  for breeding, when the weevils in the Moroccan High Atlas inactively hide between the roots deeply in the soil of their host-plants because of low night temperature?
Bionomy
A lot of specimens of the new species were sieved from a very wet slope on the north side of Tizi-n-Test in the Moroccan High Atlas and from detritus and roots of Euphorbia nicaeensis All. Strong specimens of this Euphorbiaceae occurring totally isolated here grew between broom shrubs and were often damaged by the skidding scree - to sprout again from the very lignified parts of the trunk (shoots). [Fig. 175.20] To compare with Euphorbia, the neighbouring broom shrubs were also sieved intensively. But not a single specimen could be obtained from the massive, damp-mouldy detritus! On the other hand, Christoph Germann (Bern) detected two larvae of the new species in a strong, dead specimen of Euphorbia nicaeensis. [Fig. 175.21] For this reason, Euphorbia nicaeensis was teared open from upside down to the root. He found the larvae in the mouldy, damp plant tissue, about 5 cm below the shoots in the root-neck. [Fig. 175.22] These larvae must be ‘stragglers’, because larvae of all known Kyklioacalles species normally develop during midsummer (in the tissue of dying plants). In the partly dead root-neck of other plants further feeding-caverns of the larvae were found.
Euphorbia nicaeensis shows a tendency to form biological races. The complex has a Mediterranean-south-Siberian distribution (steppicol); but Euphorbia nicaeensis sensu strictu has a western and central Mediterranean distribution. A population from Toscana with a creeping habit (7 - 15 cm) and with 3 - 8 umbel rays was described as var. prostrata Caruel, an Apulian with hairy capsule as var. japygica (Ten.) Arcang. [Pignatti 1982]. Therefore, in the Mediterranean area it is a wide-spread species, often showing local forms or it is a species complex. The completely isolated occurrence of this member of the Spurge family 2000 m above sea level - we didn’t find this plant at no other locality of the High Atlas! - nurtures the suspicion that the little isolated population of Tizi-n-Test could be a separate form of E. nicaeensis. On no other Euphorbiaceae we found Kyklioacalles species in the Rif Mountains, Middle Atlas, High Atlas or Anti-Atlas. So, I assume that Kyklioacalles euphorbiophilus in an endemic species of the central mountains of High Atlas (if not even of Tizi-n-Test).
Methods
These very detailed observations in the Moroccan High Atlas and especially the fact, that Kyklioacalles euphorbiophilus develops inside the root-neck of dying Euphorbia nicaeensis-plants, encouraged me to breed a Cryptorhynchinae (here: a Kyklioacalles species) for the first time at all. For this purpose I brought a small fresh, uncolonized specimen of Euphorbia nicaeensis to Germany. In a customary flat clay-flowerpot with a diameter of 18 cm and a height of 9 cm, the plant was put into a mixture of sand, a little bit of loam and small bloated clay-balls, as it is used for hydroponics, on January 6, 2003. The bloated clay-balls are used as drainage, to protect from damp and early growth of fungi. But transport and not very careful treatment of the plant in the insectarium of the CURCULIO-Institute caused a gradually dying of the outer branches. A reaction of the plant was to produce ‘trouble-shoots’. [Fig. Z2]. This was even intended, because at ‘locus typicus’ mainly plants are colonized being damaged by the skidding scree, to sprout again from the lignified segments of the trunk.
On January 8, 2003, I put 6 females and 5 males in the glass-insectarium of the size: 30 cm x 30 cm x 40 cm (length x width x height). There were also 4 cm of sand around the pot, pressed down slightly and watered regularly. [Fig. Z2] The plant itself was still treated ‘uncarefully’, only sprayed in two-day intervals and watered weekly and sparsely. The animals oriented towards the plant immediately after they were put in; at night they climbed the branches of the plant and during the day they retreated to the clay-balls deeply between the roots. In the evening twilight the weevils climbed the stems and copulated here. They were observed feeding from dead parts of the plant (‘rasp-feeding’) [Fig. 175.23]. The plant was taken out by night together with the pot to document the events with a high-resolution digital camera. [Fig. 175.23] [Med.Eup].
Breeding
In March, the plant tried to produce shoots for a last time, before drying up [Fig. Z2]. The first 4 larvae could be taken from the completely dried root-neck on May 21, 2003. [Fig. Z1]. They had reached the last larval stage. On June 10, 2003, I found the two first pupae in their pupal chambers, filled with used rasp-shavings. Astonishingly, the root-neck and the trunk, projecting about 5 cm and containing the larvae, remained relatively damp [Fig. Z3]. Only occasionally the plant was watered and slightly sprayed in its dried state. The temperature in the insectarium was 21 °C until end of April, and afterwards about 26 °C. The larvae were found in the primary root, the subterranean root-neck, in the trunk and in the lower small forks of the branches of Euphorbia nicaeensis; but not in the dried twigs.
On June 23, 2003, the emerging of the first immature specimen could be photographed [Fig. Z4]. The egg-shaped pupal chamber was 8 mm long and 4.5 mm wide. To film the emerging from the pupa, the pupal chamber was partly opened on one side [Fig. Z5]. On the same day, further photographs were taken of an already far developed pupa. The pupa was put into a small Eppendorf-vessel and covered with dead, small-rasped substratum of the Euphorbiaceae. In the apical part of the Eppendorf-vessel, the pupa made a new pupal chamber by violent movement [Fig. Z6].
On June 26, 2003, further photographs were taken from the same pupa; the dark eyes are clearly to be recognized already now [Fig. Z7]. On July 1 or 2, 2003, the first animal must have emerged, because on July 3, 2003, I found a very immature (but no more white-colored) imago.
On June 30, 2003, the dismantling of the trunk segment was continued. It was found:

• 1 still white imago [Fig. Z8]; it was put in a small Eppendorf-vessel. 4 days later, it was completely hardened,

• 1 completely hardened imago in its pupal chamber,  

• 1 pupa; the imago emerged on July 2, 2003; but it stayed in its pupal chamber until mortification on July 6, 2003.

• 1 larva of the last larval stage [Fig. Z11] and

• further larvae (of all larval stages) and pupae in the more dry, upper part of the lignified trunk; right below the broken twigs long time ago. The root- and twigless trunk-segment (about 3 x 5 cm) was photographed [Fig. Z9] and put back to the original place. It seems to be possible, that such small trunks are transported over long distances by wind or water and that they are responsible for the main spreading of the species: Larvae and pupae and (completely hardened) adults can obviously spend weeks or even months  inside these small trunks. [Fig. Z10] They are outstandingly well protected and only wait for the total breakdown of the small trunks, instead of being partly decomposed by the activity of the larvae. They don’t show any own efforts to free themselves! Some larvae, pupae and a still white imago were put in Eppendorf-vessels for further development. They could be bred to complete imagos under constant observation.

On July 6, 2003, the roots already separated from the above-ground trunk segment  were digged out; then, from the central,
damp and totally rasped root-area 3 pupae, 1 big and 1 small larvae could be taken. [Fig. Z12] Then, the trunk segment still containing pupae and larvae was preserved. [Fig. Z9] Not until July 9, 2003, the last larvae were taken from the trunk segment, deadened and boiled with water and finally preserved in alcohol.
From 11 imagos, put in the insectarium on January 8, 2003, 8 could be found again. (Taking many photos and videos regularly during the whole 7 months, it was unavoidable that a few animals could escape). To ensure a constant observation, six parental weevils were put in a small plastic box. Feeding-tracks were found on completely dried stems of Euphorbia nicaeensis [Fig. Z13]. After mortification on July 22, 2003, two mature eggs could be obtained from a female.
(It is not necessary to tell, that a continuation of breeding was not intended, because the host-plant Euphorbia nicaeensis (from the Moroccan High Atlas) didn’t stand at my disposal).  
Discussion and Preview
From this first successful breeding (as I know) of a Cryptorhychinae unable to fly, a member of the genus Kyklioacalles, first clues for a more standardized breeding could be obtained.
1.      It seems that only plants during the process of dying make possible this success. Dead wood possibly still contains larvae and pupae, but the females don’t use it for laying eggs, in my mind. All experiences from my studies on the Macaronesian islands clearly show, that Cryptorhynchinae belong to the very first colonizers of such plants, that are in the process of dying (f.e. introduced by wind-break). [Stüben 2000b][Stüben 2000j][Stüben 2000][Sprick & Stüben 2000]; Cossoninae are following much later (f.e. Mesites, Cossonus, Phloeophagus). Therefore, stressed plants or even fresh plant-parts should be sufficient, to start a successful breeding. It is important, that the supply of toxic plant compounds - as in Euphorbiaceae - was already stopped to a great extent!
2.      Larvae of Cryptorhynchinae seem to be extremely enduring and subsist on very little. They survived even a drying for weeks of the upper trunk-segments and forks of the twigs in March 2003 without any damage. (I was on an excursion on this point in time). For that reason, the whole substratum for development should be kept relatively dry, and it should be drained sufficiently.
3.      After emerging from the pupa, the adult weevils still stay for weeks, if not for months, in their pupal chambers. Not before the first precipitation in autumn and/or winter and softening of plant tissue, the animals free themselves from their substratum, in which they have developed. [Stüben 2000e] An active spreading seems to be very improbable for these flightless Cryptorhynchinae, and it might occur only very rarely. Passive transport of the died and completely dried developmental substratum by wind or water should play a much more crucial role for the colonization of new habitats. (The suspicion that lignified flotsam could also play an important role for the (first) colonization of islands, doesn’t seem to be false). Therefore, twigs, branches and parts of the roots should be cut open regularly, to be able to document the phase of metamorphosis!
At this place I am unfortunately not allowed to describe the eggs, larvae and pupae of Kyklioacalles euphorbiophilus and to designate holo- and paratypes, according to the ‘International Code of Zoological Nomenclature’ [ICZN: 2000: § 9.8.]; see [Bayer & Stüben 2000]. Unfortunately, contributions with nomenclatural actions still may not be published in the World Wide Web - as is fixed by the commission. Therefore, I have to turn attention of the readers to our next SNUDEBILLER 5 / 2004: Here will be catched up, what could have been better documented at this place and in this context.
Acknowledgements
My special thanks is dedicated to Christoph Germann (Bern/Switzerland). We discovered the new species Kyklioacalles euphorbiophilus at Euphorbia nicaeensis in the High Atlas on one of our numerous common journeys to Morocco. My thanks is also expressed to Peter Sprick (Germany/Hannover), who translated this contribution into English.  
References
Bayer, Chr. & Stüben, P.E. (2000): Vergleichende Untersuchungen an Larven aus der Acalles-Verwandtschaft. - Cryptorhynchinae-Studie 14 - in: Stüben, P.E. (2000b), SNUDEBILLER 1 (CD ROM), CURCULIO-Institute, D-Mönchengladbach: 170-181
ICZN (2000): Internationale Regeln für die zoologische Nomenklatur (offizieller deutscher Text, ausgearbeitet von O. Kraus), - Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg (NF), 34: 232 S., Goecke & Evers: Keltern-Weiler.  
Pignatti, S. (1982): Flora d’Italia. Vol. secondo. Bologna, 732 pp.
Sprick, P. & Stüben, P.E. (2000): Ökologie der kanarischen Cryptorhynchinae außerhalb des Laurisilva. - Cryptorhynchinae-Studie 11 - in: Stüben, P.E. (2000b), SNUDEBILLER 1 (CD ROM), CURCULIO-Institute, D-Mönchengladbach: 318-341
Stüben, P.E. (2000b): (Ed.), Die Cryptorhynchinae der Kanarischen Inseln. Systematik, Faunistik, Ökologie und Biologie. - SNUDEBILLER 1 (CD ROM); mit 910 Farbfotos, 266 REM-Aufnahmen, 118 Verbreitungskarten, 18 Ton- u. 1 Video-Aufnahme, 1. Edition, CURCULIO-Institute, D-Mönchengladbach: 413 pp.
Stüben, P.E. (2000e): Die Arten des Genus Acalles von den Kanarischen Inseln. - Cryptorhynchinae-Studie 5 - in: Stüben, P.E. (2000b), SNUDEBILLER 1 (CD ROM), CURCULIO-Institute, D-Mönchengladbach: 22-98
Stüben, P.E. (2000j): Biogeographie und Evolution der kanarischen Cryptorhynchinae. - Cryptorhynchinae-Studie 10 - in: Stüben, P.E. (2000b), SNUDEBILLER 1 (CD ROM), CURCULIO-Institute, D-Mönchengladbach: 293-306
Stüben, P.E. (2002): Die Cryptorhynchinae von den Inseln Madeiras und Salvagens. Taxonomie, Bionomie, Biogeographie und Evolution. (Coleoptera: Curculionidae). - SNUDEBILLER 3, Studies on taxonomy, biology and ecology of Curculionoidea, Mönchengladbach: CURCULIO-Institute, 88-195.
Stüben, P. E. (2003a): Revision des Genus Kyklioacalles und Beschreibung der Untergattung Palaeoacalles subg. n. unter Heranziehung phylogenetischer, morphogenetischer und biogeographischer Aspekte (Curculionidae: Cryptorhynchinae). - SNUDEBILLER 4, Studies on taxonomy, biology and ecology of Curculionoidea, Mönchengladbach: CURCULIO-Institute: 116 - 166.

Address:
Dr. Peter E. Stüben
CURCULIO-Institute
Hauweg 62
D-41066 Mönchengladbach
E-Mail: P.Stueben@t-online.de