Karaytugia aydini, comb. nov.
Creators: name: Huys, Rony
name: Mu, Fanghong
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Hexanauplia
Harpacticoida
Parastenheliidae
Karaytugia
Karaytugia aydini

description: Karaytugia aydini (Kuru & Karaytuğ, 2015) comb. nov.
Parastenhelia aydini Kuru & Karaytuğ, 2015
Original description. Kuru & Karaytuğ (2015): 121–127; Figs 1 –8.
Type locality. Turkey, Kızkalesi, Mersin (36°27.473’ N, 34°08.647’ E); sand at 0.3 m depth adjacent to rocky shore.
Notes. Kuru & Karaytuğ (2015) observed slight sexual dimorphism in the ornamentation of caudal ramus seta III (naked in ♀, minutely bipinnate in ♂). This observation needs confirmation based on a larger sample since only two males were examined. The authors also claim that the male antennule is 11-segmented and present the armature pattern as follows: 1-[1], 2-[10], 3-[5], 4-[6], 5-[3], 6-[1+ (1 + ae)], 7-[1 + 6 modified], 8-[1 + 2 modified], 9-[1], 10-[4], 11-[6 + acrothek]. The presence of four segments (their segments 8–11) distal to the geniculation is correct, however, the segmentation pattern proximal to the geniculation is ambiguous even though the authors illustrated it from different angles (their Fig. 7B–E). Comparison with the ancestral male harpacticoid pattern (as in Hamondia superba Huys, 1990: cf. Huys & Boxshall 1991) clarifies the homologies of the proximal segments in K. aydini comb. nov. and reveals some observational errors in the original description. The homologies between actual segments (indicated in Arabic numerals) and ancestral segments (in Roman numerals) in the male groundpattern of the Harpacticoida are as follows (Huys & Boxshall 1991: 115, Fig. 2.4.4): 1-[I], 2-[II], 3-[III – VIII], 4-[IX – XII], 5-[XIII], 6-[XIV – XVI], 7-[XVII], 8-[XVIII], 9-[XIX – XX], 10-[XXI – XXII], 11-[XXIII], 12-[XXIV], 13-[XXV], 14-[XXVI – XXVIII]. In this ancestral 14-segmented pattern the large aesthetasc is situated on segment 6 (and on segment 4 in the female), however, in all members of the Parastenheliidae segment 2 is not expressed as a discrete segment, forming instead a compound segment [II – VIII] and making the aesthetasc originate from actual segment 5. According to Kuru & Karaytuğ (2015) the aesthetasc arises from segment 6 in K. aydini comb. nov. This condition is extremely unlikely and is further exacerbated by the fact that ancestral segment XIII (= segment 4 in the parastenheliid groundpattern), which is expressed as a U-shaped bisetose sclerite in most male harpacticoids, was overlooked (although there is a hint of it in their Fig. 7D), thus effectively shifting the position of the aesthetasc even further to segment 7. Their alleged sixth segment (their Fig. 7C–D) shown to carry this sensory structure is in reality the cylindrical pedestal of segment 5 [= XIV – XVII] which partly conceals the real segment 6 [= XVIII] in ventral aspect. Finally, their segment 7 is a compound double segment homologous to ancestral segments XIX – XX. Kuru & Karaytuğ (2015) claim that the armature for this segment is “1 + 6 modified” but this is almost certainly based on an observational error. Male harpacticoids typically display two spiniform elements on the anterior surface and one seta at the anterodistal corner (cf. Huys & Boxshall 1991: Fig. 115) and the same pattern is expressed in K. aydini comb. nov., the supernumerary elements being spinules. Similar spinular or setular ornamentation elements have been recorded on the same antennulary segment in many other harpacticoids such as in Neobradya pectinifera Scott, 1892 (Huys 1987: Fig. 1B).
The type species was also collected from Denizy-ıldızı beach in Urla (İzmir Province) in the Aegean Sea (Kuru & Karaytuğ 2015).
description: Published as part of Huys, Rony & Mu, Fanghong, 2021, Johnwellsia, a new intertidal genus of Parastenheliidae (Copepoda, Harpacticoida) from the Taiwan Strait, China, including a review of the family and key to genera, pp. 236-318 in Zootaxa 5051 (1) on pages 296-297, DOI: 10.11646/zootaxa.5051.1.13, http://zenodo.org/record/5572417