Gammarus komareki aznavensis, Özbek & Received & Online, 2014

Özbek, Murat, Received, Hamidreza Rasouli & Online, Published, 2014, Gammarus komareki aznavensis subsp. nov., a new amphipod subspecies from Iran (Amphipoda: Gammaridae), Turkish Journal of Zoology 38 (3), pp. 326-333 : 327-332

publication ID	https://doi.org/ 10.3906/zoo-1306-1
publication LSID	lsid:zoobank.org:pub:53098B44-58E5-4C8B-A05C-62C0041CF4D8
persistent identifier	https://treatment.plazi.org/id/2708D006-6D3E-471C-E123-FC1EFC081709
treatment provided by	Felipe
scientific name	Gammarus komareki aznavensis
status	subsp. nov.

Treatment

Gammarus komareki aznavensis View in CoL subsp. nov. ( Figures 2A– 2F View Figure 2 , 3A–3L View Figure 3 , 4A–4E View Figure 4 , 5A–5J View Figure 5 , 6A–6F View Figure 6 )

Material examined. Holotype male, 8.7 mm (ESFM-MALI/11-01); Aznav County (37°34′50″N, 48°34′23″E), Khalkhal-Ardabil , northwestern Iran ( Figure 1), 25 May 2011; collected by H Rasouli. GoogleMaps Allotype female, 7.5 mm (ESFM-MALI/11-02), same data as holotype. Paratypes (many males and females) (ESFM-MALI/11-03), same data as holotype.

Diagnosis. A small species (maximum length 9.2 mm). Big, kidney-shaped eyes, short antenna 1 (13 to 21 segmented flagellum), peduncle and flagellar segments of antenna 2 very densely setose, anterior margins of pereopods 5 to 7 with some setae longer than the spines, posterior margins of merus and carpus of pereopod 3 densely setose, flat urosomites, setose outer margin of the outer lobe of the third uropod, endopodite/exopodite ratio of third uropod 0.65.

Description of holotype male.

Head ( Figure 4D View Figure 4 ): inferior antennal sinus deep. Eyes very large, kidney-shaped.

Antenna 1 ( Figure 2A View Figure 2 ): shorter than half the body length; setation weak, peduncular segments bear a few distal setae shorter than diameter of segment where they implanted; article 1 stout; primary flagellum with 17 articles; accessory flagellum with 3 articles.

Antenna 2 ( Figure 2B View Figure 2 ): peduncular segments armed with 10–12 groups of long setae. Setae along the ventral margins of peduncular segments are more than twice as long as the diameter of the segment; setae on the dorsal side of peduncular segments are shorter; flagellum comprises up to 11 segments; dorsal and ventral parts of segments with many long setae (more than 2 times longer than segment); flagellar segments slightly swollen; calceoli absent.

Left mandible ( Figure 3G View Figure 3 ): incisor with 5 teeth; lacina mobilis with 4 dentitions; molar triturative; second article of palp bears 10 setae; third segment armed with 23 D-setae, 5–6 E-setae; 1 group of A-setae, 1 group of B-setae; C-setae absent.

Right mandible ( Figure 3F View Figure 3 ): incisor 4-dentate, lacina mobilis bifurcate.

Maxilla 1 ( Figure 3A View Figure 3 ): inner plate with 15 plumose setae, outer plate with 9 serrated spines, article 2 of right palp stout, with 4 blunt spines on distal part, inner margin with no stiff setae; 2 stiff setae on outer margin article 2 of left palp with 6 sharp spines, 3 stiff setae.

Lower lip ( Figure 3E View Figure 3 ): inner lobe absent. Upper lip ( Figure 3C View Figure 3 ): convex, with minute setae on distal part.

Maxilla 2 ( Figure 3D View Figure 3 ): inner plate with diagonal row of 15 plumose setae.

Maxilliped ( Figure 3B View Figure 3 ): inner plate with 3 apical spines and 1 subapical spine; outer plate with row of 10–11 spines on medial margin and 3–5 pectinate apical setae.

Coxal plate 1 ( Figure 2C View Figure 2 ): slightly dilated on distal margin, with 3 setae on anterodistal margin and 1 seta on posterodistal margin.

Coxal plates 2 and 3 ( Figures 2D and 2E View Figure 2 ): subrectangular. Coxal plate 2 with 3 short setae on anterodistal corner, 1 seta on posterodistal corner. Coxal

ÖZBEK and RASOULI / Turk J Zool plate 3 with 3 short setae on anterodistal corner, 1 seta on posterodistal corner. Ventral margin of coxal plate 4 slightly convex ( Figure 2F View Figure 2 ), with 3 setae on anterodistal corner, 4 setae on posterior margin.

Coxal plates 5 and 6 ( Figures 5A and 5B View Figure 5 ): bilobate. Anterior lobe of coxal plate 5 small with 1 seta, posterior lobe with 2 setae on posterodistal corner. Coxal plate 6 with 2 setae on posterodistal corner.

Coxal plate 7 ( Figure 5C View Figure 5 ): with 3 setae on posterior margin. Coxal gills 2–7 present.

Gnathopod 1 ( Figure 2C View Figure 2 ): basis with a few long setae (up to 2.0 times longer than diameter of segment) on both anterior and posterior margins; carpus and propodus elongate; propodus with 1 and 2 groups of setae on outer and inner sides of anterior margin, respectively; palm oblique, bearing 1 blunt median spine and 4 (2 + 2) palmar angle spines in addition to some small spines on posterodistal margin of the segment; dactylus with 1 seta on its outer margin.

Gnathopod 2 ( Figure 2D View Figure 2 ): basis with long setae (up to 2 times longer than diameter of segment) on anterior and posterior margins; anterior margin of carpus with 1 group of setae; propodus subrectangular, with 4 groups of setae on anterior margin; many groups of setae on posterior margin; median spine present, with 3 spines on posterodistal margin; dactylus with 1 seta on outer margin.

Pereopod 3 ( Figure 2E View Figure 2 ): anterior and posterior margins of basis bear a few long setae (up to 2 times longer than diameter of segment); merus and carpus densely setose along their posterior margins, setae on posterior margins long (up to 2.5 times longer than diameter of segment where they implanted); dactylus with 1 serrated seta on outer margin, 2 setae at joint of unguis.

Pereopod 4 ( Figure 2F View Figure 2 ): anterior and posterior margins of basis with a few long setae; posterior margins of merus and carpus bear a few groups of setae (much shorter and sparser than those of pereopod 3); dactylus with 1 serrated seta on outer margin, 2 setae at joint of unguis.

Pereopods 5–7 ( Figures 4A–C View Figure 4 ): subequal in length; basis of pereopod 5 subrectangular; bases of pereopods 6 and 7 quadrangular and relatively elongated, anterior margins with 3–4 short spines, posterior margins with 10–12 short setae; articles 4–6 with 2–5 groups of spines and/or setae on anterior margin of each segment; anterior margin of segments 4 and 5 with a few setae longer than spines; sixth segments of pereopods 5–7 with 2 groups of

ÖZBEK and RASOULI / Turk J Zool long setae along their posterior margins, dactylus with 1 seta on outer margin, 2 setae at joint of unguis.

Epimeral plates 1–3 ( Figure 3L View Figure 3 ): epimeral plate 1 holds 6 setae on anterior corner; epimeral plate 2, posterodistal corner slightly pointed, with 3 spines on anteroventral margin; epimeral plate 3, posterodistal corner slightly pointed (never in the form of a sharp hook), with 3 spines on anteroventral margin.

Pleopods 1–3: subequal; peduncle with some setae, bearing 2 retinacula accompanied by a few setae; rami with 19–25 segments, fringed with plumose setae.

Urosomites 1–3 ( Figure 2 View Figure 2 ): almost flat; each urosomite bears a dorsomedian and 2 dorsolateral groups of armaments on their posterior margins. Dorsolateral groups of first and second urosomites consist of 2 spines and 4–6 longer setae. The dorsomedian group of urosomite 1 consists of 1 spine and 4–5 longer setae, similar to urosomite 2. Third urosomite bears no spine (2–3 setae only) in its dorsomedian group.

Uropod 1 ( Figure 3K View Figure 3 ): peduncle longer than rami, with 1 spine on outer margin; inner margin with 3 marginal and 2 distal spines; exopodite slightly shorter (about 0.9 times as long as endopodite) than endopodite, with 2 spines on inner margin; endopodite with 2 spines on inner margin.

Uropod 2 ( Figure 3J View Figure 3 ): peduncle with 1 marginal spine on inner margin, in addition to 1 distal spine; exopodite shorter than endopodite (about 0.9 times as long as endopodite); exopodite with 1 spine on outer margin, inner margin bare; endopodite with 1 spine on inner margin.

Uropod 3 ( Figure 3I View Figure 3 ): peduncle with 4–6 distal spines; endopodite shorter than exopodite (about 0.65 times as long as exopodite), with many plumose setae and some shorter simple setae on both margins; article 1 of exopodite with 4 groups of spines on outer margin together with many simple setae; inner margin with many simple and plumose setae, first segment of exopodite bears 3–4 distal spines, article slightly 2× longer than adjacent spines.

Telson ( Figure 3I View Figure 3 ): deeply cleft; each lobe with 2 distal spines together with 4–5 longer distal setae, a few lateral setae on outer margin; the length of distal and lateral setae about 1.3 and 0.6 times as long as the length of telson, respectively.

Description of allotype female.

Antenna 1 ( Figure 5A View Figure 5 ): peduncle segments with few setae as long as the diameter of the segment where they implanted; primary flagellum with 19 segments; accessory flagellum with 4 segments.

ÖZBEK and RASOULI / Turk J Zool

Antenna 2 ( Figure 5B View Figure 5 ): peduncle segments bear 4–5 groups of setae on dorsal margin; setae on ventral margin of fifth peduncle segment more than twice as long as the diameter of the segment; flagellum with 11 segments; the setation of flagellar segments is rich and the segments are slightly swollen; calceoli absent.

Gnathopod 1 ( Figures 5C and 5D View Figure 5 ): basis with 4 and 7 long setae on both anterior and posterior margins, respectively; setae can be more than 2 times longer than the diameter of basal segment on both margins; propodus ovate with 3 groups of setae on anterior margin, palm not as oblique as that of male, with 2 spines on posterior corner, dactylus with 1 seta on outer margin.

Gnathopod 2 ( Figures 5E and 5F View Figure 5 ): carpus and propodus elongate, propodus subrectangular, medial palmar spine absent, bearing 2–3 spines on posterior corner and some small spines on inner margin.

Pereopods 3–7 ( Figures 5G, 5I, 5J View Figure 5 , 6A, and 6B View Figure 6 ): more setose than those of the male.

Uropod 3 ( Figure 5H View Figure 5 ): endopodite shorter than exopodite (about 0.61 times as long as exopodite); endopodite with simple and plumose setae on both margins; article 2 of exopodite slightly longer than the spines on distal part of first article; inner margin of exopodite with a few plumose setae; outer margin of exopodite with 3 groups of spines accompanying some simple setae longer than the spines.

Oostegites are broad, ovate, and occur on pereopods 2 to 5.

Etymology. The subspecies name is derived from the name of the type locality, Aznav.

Habitat. Specimens were sampled from a slow running limnocrene spring with dense submerse aquatic plants in Aznav County (Khalkhal-Ardabil). Some of the physicochemical characters were as follows: salinity: 0.2 ppt; pH: 7.2; electrical conductivity: 310 µS 25 °C; water temperature: 11 °C; maximum depth: 130 cm.

Variability. Among the 20 specimens, the number of flagellar segments of antenna 1 varied from 13 to 21. We never observed minute, ovoid eyes among the paratype specimens. In general, eyes were as long as or slightly longer than the diameter of the first peduncle segment of antenna 1. The length and number of the setae along the anterior margins of pereopods 5 to 7 were variable in males; some of them have more setose pereopods 5–7 than those of the holotype.