Callianassa reinhardpalorum, Hyžný, 2020

Hyžný, Matúš, 2020, Revision of the Miocene shrimp Callianassa kerepesiensis Müller, 1976 (Malacostraca, Decapoda), with a description of a new species, Zootaxa 4801 (2), pp. 363-373 : 367-369

publication ID	https://doi.org/ 10.11646/zootaxa.4801.2.10
publication LSID	lsid:zoobank.org:pub:2AF7F1AE-D0CD-46B9-8F93-4ED59591206B
persistent identifier	https://treatment.plazi.org/id/6731C0A4-E655-46E8-A619-2CDB7D2A759C
taxon LSID	lsid:zoobank.org:act:6731C0A4-E655-46E8-A619-2CDB7D2A759C
treatment provided by	Plazi
scientific name	Callianassa reinhardpalorum
status	sp. nov.

Treatment

Callianassa reinhardpalorum sp. nov.

Figures 3 View FIGURE 3 A–T, 4A–B

urn:lsid:zoobank.org:act:6731C0A4-E655-46E8-A619-2CDB7D2A759C

Callianassa kerepesiensis — Förster, 1979. p. 90, text-fig. 1, pl. 1, fig. 5.

Callianassa cf. kerepesiensis — Müller, 1984, p. 52, pl. 7, figs. 1–2.

Diagnosis. Manus of major cheliped as long as high or slightly elongate, lower and upper margins keeled, converging distally; occlusal surface of fixed finger finely serrated or completely smooth; major cheliped carpus as long as high, upper margin keeled, proximo-lower margin keeled and rounded.

Etymology. The species name acknowledges late Reinhard Förster (1935–1987) and Pál Müller (1935–2015), who were among the first to collect and figure the material belonging to this species.

Type material. Holotype: HNHM M.86.64A , right propodus . Paratypes: HNHM M.86.64B , right propodus ; HNHM M.86.64C , right propodus ; HNHM M.86.64D , left propodus ; HNHM M.86.64E , right propodus ; HNHM M.86.64F , left propodus ; HNHM M.86.64G , left propodus . All elements are of major pereiopod 1 (cheliped) coming from the Örs vezér tere ( MOE) locality in Budapest, Hungary.

Additional material. Örs vezér tere ( MOE), Budapest, Hungary: HNHM 2019.171.1, right propodus; HNHM 2019.171.2,left propodus; HNHM 2019.171.3,right propodus; HNHM 2019.171.4,left propodus; HNHM 2019.171.5, right propodus; HNHM 2019.171.6, right propodus; HNHM 2019.171.7, left propodus; HNHM 2019.171.8, right propodus; HNHM 2019.171.9, left propodus; HNHM 2019.171.10, left carpus; HNHM 2019.171.11, right carpus; HNHM 2019.171.12, left carpus; HNHM 2019.171.13, left carpus. Mátraverebély-Szentkút, Hungary: HNHM INV 2019.1367, eight isolated cheliped elements. Starý lom, Bratislava, Slovakia: KGP-MH SL-001, fragmentary left major cheliped (P1) propodus; KGP-MH SL-002, near-complete left major cheliped (P1) propodus.

Description. Major cheliped (P1) manus subrectangular, as long as high or slightly longer than high; upper and lower margins keeled, converging distally; distal margin rounded, sometimes ornamented with tubercles at lower portion, with or without notch (incision) below articulation with dactylus; both lateral surfaces smooth. Fixed finger variously long with tip pointing upward; occlusal surface finely serrated or completely smooth. Major cheliped (P1) carpus approximately as long as high, unarmed; upper margin keeled; proximo-lower margin rounded and keeled.

Variations. There are two morphotypes of the species. The manus of the more robust one has a distinct notch below the articulation with the dactylus and unarmed fixed finger. The slender morphotype represents the manus without the notch and the fixed finger is armed with fine serration ( Figs 3L, P View FIGURE 3 ). The tip of the dactylus is bent strongly upward especially in the robust morphotype.

Occurrence. The species has so far been reported from the middle Miocene (Badenian) of Nawodzice, Poland ( Förster 1979), Mátraverebély-Szentkút, Hungary, and Örs vezér tere (Budapest area), Hungary ( Müller 1984). The newly recovered material comes from the locality of Starý lom (sensu Hyžný et al. 2012), where Badenian finegrained yellow/rusty sands and soft sandstones are exposed.

Remarks. Förster (1979) reported on Callianassa kerepesiensis from the Badenian of Nawodzice, Poland. Later, Müller (1984) did not consider the material of Förster (1979) as conspecific with his taxon, and together with additional material from the Badenian of the Budapest area, Müller classified it in open nomenclature as ʻ Cal- lianassa ʼ cf. kerepesiensis . Müller (1984: 52) noted that ʻ Callianassa ʼ cf. kerepesiensis is remarkably similar to C. kerepesiensis , but its fixed finger bears only one rudimentary tooth near its end, and the undulated region is missing on the inner lateral surface of the manus. Actually, the taxa differ from one another in more characters. There is no longitudinal ridge on the fixed finger of ʻ Callianassa ʼ cf. kerepesiensis and upper and lower margins are always converging distally, which is not the case in C. kerepesiensis . Consequently, the species kept for so long in open nomenclature is given a new name here, Callianassa reinhardpalorum sp. nov.

The propodus outline and the range of variation expressed in Callianassa reinhardpalorum sp. nov. conform to the revised genus concept of Callianassa presented by Poore et al. (2019). The Mediterranean species Callianassa subterranea ( Montagu, 1808) shows especially strong similarities to Callianassa reinhardpalorum sp. nov. In Cal- lianassa subterranea the upper margin of the major cheliped (P1) manus is converging slightly distally and there is a distinct notch (incision) below the articulation with the dactylus ( Ngoc-Ho 2003), the character present also in C. reinhardpalorum sp. nov. In extant representatives this notch, however, appears to be present mainly in larger males ( Sakai 2005: figs. 5A, 6A), whereas serrated fixed fingers characterize the females ( Ngoc-Ho 2003: fig. 9B). Therefore, it is tempting to interpret the two recognized morphotypes of C. reinhardpalorum sp. nov. as sexual dimorphism. However, no definitive proof for such a conclusion is available.