Holosoma rambouseki
Creators: name: Guéorguiev, Borislav
name: Liang, Hongbin
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Carabidae
Holosoma
Holosoma rambouseki

description: “ rambouseki ” species group
Diagnosis. The species group includes five wingless species that possess the following synapomorphies: (1) metepisternum one-and-a-half times or more wider than long; (2) extraordinarily elongate spermatheca; and (3) apical gonocoxite short, subtriangular, with dorsomedial ensiform seta situated near the middle or equidistant from the middle and the base.
In addition, the species from the “ rambouseki ” group have the anterior angles of pronotum more projected and pointed, as well as the parascutellar stria more obliterated than in other representatives of the genus (except P. coelestinus which also has an obliterated parascutellar stria). Further, three species (P. hunanensis, P. leigongshanicus, and P. rambouseki) have a metatrochanter more or less pointed at the apex (Figs 10E, 11D, 12H). All five representatives are wingless, with fused elytra and reduced metathoracic wings.
Notes. Pseudoodes hunanensis and P. leigonshanicus (supposedly also P. emeishanicus and P. tianlinenis whose females are still unknown) have very long, undifferentiated spermatheca. On the other hand, P. rambouseki has a spermatheca also quite long but slightly differentiated (like P. ampliusculus) into a seminal canal and a receptaculum. Tendencies to slightly differentiated and undifferentiated spermatheca are aberrant conditions within Pseudoodes. They occur in species from the “ ampliusculus ” and “ rambouseki ” groups, and are considered a reversal (loss of derived trait present in the common ancestor) due to considerable lenghtening of the apical part of spermatheca (i.e., receptaculum). Similarly, there are two kinds of attachment of the spermathecal gland to spermatheca among species of the “ rambouseki ” group, each linked, respectively, to the above mentioned two kinds of spermatheca. Pseudoodes rambouseki has a spermathecal gland attached at the apical third of spermatheca while P. hunanensis and P. leigongshanicus have the spermathecal gland connected at the proximal half of the seminal canal.
Likely the species of this group derived from a common ancestor (supposed form close to P. cribristernis and/or P. ampliusculus) via isolation in the high mountainous areas of south and southwest China. Two groups are distinct: (1) P. rambouseki, having bursa copulatrix with a small dorsal sclerite, spermathecal gland attached at apical third of seminal canal, apical lamella of median lobe narrow, bent to left and rounded at tip, male mesotibia considerably curved and dilated distally, male protarsomere 2 very broad, and MA/MM relatively low; and (2) P. hunanensis and P. leigongshanicus, having bursa copulatrix without sclerite, spermathecal gland attached at middle of seminal canal, apical lamella of median lobe wide, straight and more or less pointed at tip, male mesotibia almost straight, slightly dilated distally, male protarsomere 2 moderately broadened, and MA/MM higher. Though females of P. emeishanicus and P. tianlinensis are unknown, judging from the structure of the median lobe (apical lamella similar to that of the two species from Hunan and Guizhou) and less broadened male protarsomere 2, we believe these species belong to the second group.
description: Published as part of Guéorguiev, Borislav & Liang, Hongbin, 2020, Revision of the Palaearctic and Oriental representatives of Lachnocrepis LeConte and Oodes Bonelli (Coleoptera: Carabidae), with special account on Chinese species, pp. 1-89 in Zootaxa 4850 (1) on pages 25-27, DOI: 10.11646/zootaxa.4850.1.1, http://zenodo.org/record/4407072