Harmonicon F.O.P.-Cambridge, 1896

Drolshagen, Bastian & Baeckstam, Christian M., 2011, Notes on the genus Harmonicon F. O. P. - Cambridge, 1896 (Araneae, Dipluridae) with description of a new species from French Guyana, ZooKeys 112, pp. 89-96 : 90-91

Harmonicon F.O.P.-Cambridge, 1896

Harmonicon F.O.P.- Cambridge 1896: 755; Maréchal and Marty 1998: 500.

Diagnosis:

Harmonicon is one of the genera of the subfamily Diplurinae with a lyra prolaterally on the maxillae. It differs from Diplura by the shape of the lyra bristles (claviform in Diplura rather than hookshaped in Harmonicon ), a more dense scopula on Ta I and II, the presence of a dense scopula in more than the apical third of pedipalpal tarsus, the presence of a scopula in the apical third of most leg metatarsi, and by the leg tarsi being pseudosegmented instead of showing only a few cracks. Harmonicon can be distinguished from Trechona by a less dense scopula on Ta III and IV, and by fewer lyra bristles arranged in a single row.

Remarks:

Cambridge (1896) and Maréchal and Marty (1998) regarded the presence of five lyra bristles a key feature for the genus. Research on the development on the new species described here showed that younger specimens have fewer lyra bristles than fully grown ones. Therefore the number of lyra bristles should no longer be considered diagnostic for Harmonicon . Maréchal and Marty (1998) stated that the leg formula of 1423 (rather than 4123 as in Diplura and Trechona C.L. Koch, 1850), is also a key feature of the genus Harmonicon , but show a leg formula of 4123 for the female holotype of Harmonicon audeae . Cambridge (1896) was incorrect in stating that the holotype of Harmonicon rufescens is a female; it is in fact a juvenile male. Maréchal and Marty (1998) did not comment on the putative synonyms of Harmonicon , Pseudohermachura Mello-Leitão, 1927 and Prosharmonicon Mello-Leitão, 1938, as well as those species formerly assigned to Harmonicon : Harmonicon nigridorsi Mello-Leitão, 1924 and Harmonicon riveti Simon, 1903. Mello-Leitão (1927) described the monotypical genus Pseudohermachura from a single female specimen of the type species Pseudohermachura catharinensis Mello-Leitão, 1927 (holotype deposited in MPSP) and did not mention the presence of a lyra at all. Bücherl (1962) redescribed Pseudohermachura catharinensis and mentioned a lyra consisting of 7-10 claviform bristles. Mello-Leitão (1938) described the monotypical genus Prosharmonicon from a single female specimen of the type species Prosharmonicon maculatum Mello-Leitão, 1938 (holotype deposited in IBSP and destroyed in the fire of 2010) and explicitly mentioned claviform lyra bristles. We therefore consider Pseudohermachura and Prosharmonicon junior synonyms of Diplura and reject the synonymies with Harmonicon established by Bücherl (1962). Simon (1903) described Harmonicon riveti from a single male specimen, of which the palpal organ, distal part of Ti I and basal part of Mt I were later illustrated in Berland (1913): pl. 7, fig. 5-6. The illustrations show a palpal organ with a strongly curved apex of the embolus and a highly elevated tubercle laterally in the basal third of Mt I. The morphology of the palpal organ and the tubercle in the basal third of Mt I in (known) males is different in those species currently assigned to Harmonicon . Mello-Leitão (1924) described Harmonicon nigridorsi from a single female specimen, he explicitly mentioned claviform lyra bristles, which is also supported by the illustration in Mello-Leitão (1926): fig. 4. We therefore support the transfer of those two species to Diplura by Raven (1985).

Key to the species of Harmonicon