Delamarephorura Weiner & Najt, 1999

Janion, Charlene, Deharveng, Louis & Weiner, Wanda Maria, 2013, Synonymy Of Spicatella Thibaud, 2002 With Delamarephorura Weiner & Najt, 1999, And Description Of Two New Species (Collembola: Tullbergiidae), Raffles Bulletin of Zoology 61 (2), pp. 657-663 : 658

publication ID

https://doi.org/ 10.5281/zenodo.5352692

persistent identifier

https://treatment.plazi.org/id/48178787-FFDF-9F51-FEE7-FC7B80354323

treatment provided by

Tatiana

scientific name

Delamarephorura Weiner & Najt, 1999
status

 

Delamarephorura Weiner & Najt, 1999 View in CoL

Syn. — Spicatella Thibaud, 2002: 206

Type species. — Mesaphorura salti Delamare-Deboutteville, 1953

Diagnosis. — Habitus and dorsal chaetotaxy similar to Metaphorura Stach, 1954 . Antenna III-organ with two large sensory clubs and two sensory rods protected by three large guard papillae and four guard chaetae dorsally; one large sensory club ventrally. Antennal segment IV with a small simple exsertile vesicle, subapical organite in latero-dorsal position, close to microsensillum; five thickened sensilla. Postantennal organ ear-like with 8–18 simple, rather large vesicles arranged obliquely to the axis in two regular rows. Pseudocelli faintly double-striate (type II of Weiner & Najt [1991], not type III as hypothesized with doubt by Thibaud [2002]), their formula per half tergite 11/122/22221 or 11/111/11111.Abdomen VI with or without crescentic ridges close to chaeta a2, with two simple anal spines, and often two lateral spiniform processes, chaetae a0 and p0 present, a small to minute medioventral process often present. Distal whorl of tibiotarsi I–III with five chaetae (ventral chaetae A4 and A5 absent); proximal whorl of tibiotarsi I–III with 3–6 chaetae; chaeta M present or absent.

Discussion. — Some chaetotaxic details given in literature descriptions have to be corrected. In the original description of Spicatella bedosae ( Thibaud, 2002: 205, Fig.7) chaeta a0 on Abd. VI has been overlooked. In the re-description of Delamarephorura salti by Weiner & Najt (1999), the tibiotarsal chaeta M is given as absent, while it is actually present. In the description of D. szeptyckii Barra & Weiner, 2009 , the tibiotarsal chaetotaxy is given as 5, 5, 4 in row B; it is actually 5, 5, 5, like in most other Delamarephorura .

Spicatella is here synonymised with Delamarephorura . In its original description ( Thibaud 2002), Spicatella was not compared to Delamarephorura , probably because the characterisation of this last genus by the presence of strong dorsal processes on the sixth abdominal tergum placed it at first sight well apart from Spicatella . Today however, several species that might be placed in these two genera are intermediate between them for this character. Actually, within this group of species, no morphological character allows to separate Delamarephorura and Spicatella except one: the presence of a very unusual interno-distal sac inside the fourth antennal segment in S. bedosae , type species of Spicatella , and only in this species ( Table 1). However, in other morphological characters, S. bedosae is very similar to other species of the group; this similarity is illustrated by the fact that Thibaud (2008) assigned to Spicatella a species that was devoid of the internal sac inside the fourth antennal segment. At this stage, this character cannot be retained as diagnostic without other morphological support, and we propose that Spicatella is sunk into Delamarephorura .

The genus Delamarephorura keys out near Dinaphorura in Dunger & Schlitt (2011) due to the development of spiniform process on Abd. VI. However, these processes vary from large to absent in Delamarephorura as redefined here, and several other characters of generic value differ between the two genera (especially PAO and AIIIO morphology). Actually, Delamarephorura is more similar to Metaphorura in most characters of supra-generic value, particularly the large size of its three guard papillae of AIIIO. The only consistent differences between these two genera is the morphology and arrangement of vesicles in postantennal organ (8–18 large, simple vesicles arranged as ear-like versus 14–28 often bilobed vesicles not arranged as ear-like in Metaphorura ). However, there are puzzling differences in the published representation of the morphology of both the AIIIO papillae and the PAO vesicles in a species like M. affinis ( Börner, 1902) , suggesting that the discrimination between Delamarephorura and Metaphorura needs to be re-evaluated, which is beyond the scope of this paper.

Darwin Core Archive (for parent article) View in SIBiLS Plain XML RDF