Chirocephalus soulukliensis, Rogers, D. Christopher & Soufi, Mahmoud, 2013

Rogers, D. Christopher & Soufi, Mahmoud, 2013, A new species of Chirocephalus (Crustacea: Anostraca) from Iran, Zootaxa 3609 (3), pp. 319-326 : 321-324

Chirocephalus soulukliensis n. sp.

( Figure 2 )

Types. Holotype, male, data: IRAN: Golestan Provence: Soulukli Wetlands, 36º 29' 64'' N – 55º 46' 22'' E, 1357m asl, April 2010, M. Soufi, deposited: Zoology Museum of Golestan (Gorgan) University (ZMGU), Arthropod collection. Allotype: same data as holotype, 1 female; Deposited: Zoology museum of Golestan (Gorgan) University (ZMGU), Arthropod collection, ZMGU.2773. Paratypes: same data as holotype, 2 females, 2 males; Deposited: Zoology Museum of Golestan (Gorgan) University (ZMGU), Arthropod collection, ZMGU.2775.

Type locality. The type locality is a natural temporary wetland, and apparently the only one of its kind in the region. Soulukli wetland is located in northwestern Golestan National Park on Bylikouh Mountain, between the semiarid east and the humid forests of the west ( Fig. 1 ). The wetland is fed by a small freshwater spring and seasonal precipitation. The climate is continental with warm summers and cold winters (1.8–36.8 ºC), with a mean rainfall of 58.22 mm, falling in spring, winter, and autumn (Kalaleh Meteorological Station data from 1999 to 2009). Maximum water depth recorded was <110cm. Soulukli Wetland is the largest natural standing water body in Golestan National Park. The bottom is generally muddy or has decaying vegetation. The wetland is dominated by aquatic macrophytes and the water is tea coloured from organic material. Water chemistry data from across four seasons demonstrated a pH range of 6.39–7.27 meq/l, electrical conductivity of 94.5–271 meq/l, total dissolved solids of 60.5-173 mg /l, and a total hardness of 100–450 mg /l (Soufi et al, 2011). The Soulukli wetland formed on the Mozdoran formation (upper Jurassic period) cherty limestone with ammonite fossils (Soufi et al. 2011). Erosion and tectonic activities formed flatiron morph in the long of Bylikouh Mountain (Soufi et al. 2011).

Etymology. The name “ soulukliensis ” refers to Soulukli Wetland in Golestan National Park, where this species was collected.

Diagnosis. Male antennal appendage a single lamella, lacking lobes or spines, and shorter than one half the length of the second antenna proximal antennomere. Apophyses large, subcylindrical, expanding distally, with a rounded apex covered in small denticles. Second antenna distal antennomeres arcuate and sinuate, with a basomedial projection, curving dorsally and covered with denticles. Females with paired, dorsolateral spiniform projections on thoracic segment III and V through XI. Genital segments with a lateral lamellar, apically acute, caudally directed projection.

Description. Average length of preserved material: 13.8 mm from apex of head to apex of telson (three males: 13.4 mm, 13.6 mm and 13.3 mm; three females: 14.1 mm, 14.0 mm, 14.2 mm).

Male. ( Figs. 2 A, 2C) Head anteriolateral corner projecting over eyestalk base. Labrum smooth. First antenna approximately equal in length to second antenna proximal antennomere. Second antenna capable of extending back to thoracopod IV or V. Second antennal proximal antennomere transversely broad, expanding distally in proximal fourth, apex truncate, with breadth three times thickness. Proximal antennomere with a posteriomedial, subcylindrical apophysis, directed posteriomedially, with apical third expanded, apex rounded and covered in sharp denticles. Proximal antennomere with an anteriomedial antennal appendage. Antennal appendage approximately one third the length of proximal antennomere, simple in form, with a single lamella, lacking lobes or spines.

Second antennal distal antennomere approximately one fourth longer than proximal antennomere, with a broad base and a posterior branch. Posterior branch greater in diameter than medial portion of antennomere, arcing posteriodorsally, covered in sharp denticles. Distal antennomere narrowing abruptly in basal fifth into an arcuate, parallel sided, subcylindrical structure. Proximal third arcing anteriorly, then arcing posteriorly and bending medially, where the structure flattens anterioposteriorly. Distal third arcs posteriorly, the distal fifth arcs medially, bearing scattered fine denticles. Apex acute.

Thoracopods serially homologous. Thoracopod I praeepipodite broad distally, lacking setae or spines, with a rounded medial notch. Epipodite subcylindrical, sac like, lacking spines or setae, smooth, twice as long as broad. Exopod lamellar, sinuate, arcing medially. Exopod laterally with 8–10 close set, stout setae directed distally. Exopod apical third margined with filiform setae, separated basally by twice their proximal width. Endopod broadly triangular, with apex slightly upturned. Endopod margined with stout spiniform setae, separated by four times their proximal width. Endites I–III rounded, as broad as long. Endite I with three stout, spiniform setae, each four to five times as long as the endite. Endite II with five stout, spiniform setae, each four to five times as long as the endite. Endite III with four stout spiniform setae, each approximately twice the length of the endite. Endite IV arcuate, rounded, three times as broad as long. Endite V arcuate, rounded, five times as broad as long. Endite IV and V margined with long plumose setae, six to seven times as long as the endite, decreasing in length medially.

Thoracopod V praeepipodite broad distally, lacking setae or spines, with a rounded medial notch. Distal corner subacute, proximal corner rounded. Epipodite lamellar, lacking spines or setae, smooth, twice as long as broad. Exopod lamellar, margined with 20–30 close set, stout setae directed distally. Endopod broadly triangular, with apex slightly upturned, directed ventrally. Endopod margined with stout spiniform setae, separated by four times their proximal width. Endites I–III rounded, as broad as long. Endite IV arcuate, rounded, three times as broad as long. Endite V arcuate, rounded, five times as broad as long. Endites margined with long plumose setae, six to seven times as long as the endite, decreasing in length on endite V medially.

Thoracopod XI praeepipodite narrow, cylindrical, five times as long as broad, tapering to an acute apex. Epipodite lamellar, lacking spines or setae, smooth, three times as long as broad, apex acuminate. Exopod broadly ovate, margined with 8–10 close set, stout setae directed distally. Endopod broadly triangular, with apex rounded. Endopod margined with stout spiniform setae, separated by four times their proximal width. Endites I–III rounded, as broad as long. Endite I with four stout, spiniform setae, each three times as long as the endite. Endite II with five stout, spiniform setae, each three times as long as the endite. Endite III with four stout spiniform setae, each approximately twice the length of the endite. Endite IV arcuate, rounded, three times as broad as long. Endite V arcuate, rounded, five times as broad as long. Endite IV and V margined with long plumose setae, six to seven times as long as the endite, decreasing in length medially.

Genital segments fused, elongated. Gonopod with rigid base bearing a subapical ventral lobe directed medially, covered in denticles on medial surface. Gonopod rigid base with apex ventral margin bearing a conical projection, directed posteriomedially and covered in denticles ventrolaterally. Everted gonopod as long as rigid base, extending nearly to the posterior margin of the first abdominal segment. Gonopod expanded distally, bearing a subconical, curved, chitinized projection, with one or two subapical denticles. A small dorsomedial lobe is present next to the eversible portion.

Female. ( Figs 2 B, 2D) Head rounded, with anterolateral corners not projecting over eyestalk base. First antenna subequal in length to second antenna. Second antenna subcylindrical, smooth. Apex anteriorly curved and apically acute.

Thoracopod I praeepipodite broad distally, with eight marginal spines, and a narrow, overlapped medial notch. Distal corner angular, proximal corner rounded. Epipodite lamellar, lacking spines or setae, smooth, twice as long as broad. Exopod lamellar, margined with 20–30 close set, stout setae directed distally. Endopod broadly triangular, with apex rounded, directed medially. Endopod margined with stout spiniform setae, separated by four times their proximal width. Endites I–III rounded, as broad as long. Endite IV arcuate, rounded, three times as broad as long. Endite V arcuate, rounded, five times as broad as long. Endites margined with long plumose setae, six to seven times as long as the endite, decreasing in length on endite V medially.

Thoracopod V praeepipodite completely divided into two overlapping, lamellar, ovate lobes, each margined with three to five spines. Epipodite cylindrical, lacking spines or setae, smooth, twice as long as broad. Exopod lamellar, margined with 20–30 close set, stout setae directed distally. Endopod broadly ovate, with apex rounded, directed distomedially. Endopod margined with stout spiniform setae, separated by four times their proximal width. Endites I–III rounded, as broad as long. Endite IV arcuate, rounded, three times as broad as long. Endite V arcuate, rounded, five times as broad as long. Endites margined with long plumose setae, six to seven times as long as the endite, decreasing in length on endite V medially.

Thoracopod XI praeepipodite completely divided into two overlapping, lamellar, ovate lobes, lacking spines, and apically subacute. Epipodite lamellar, lacking spines or setae, smooth, twice as long as broad, apically acuminate. Exopod lamellar, margined with 20–30 close set, stout setae directed distally. Endopod broadly ovate, directed distomedially. Endopod margined with stout spiniform setae, separated by four times their proximal width. Endites I–III rounded, as broad as long. Endite IV arcuate, rounded, three times as broad as long. Endite V arcuate, rounded, five times as broad as long. Endites margined with long plumose setae, six to seven times as long as the endite, decreasing in length on endite V medially.

Thorax dorsum with paired, acute, spiniform projections on segment III and V to XI. Thoracic segment XI with a lateral, posteriorly directed spiniform lobe projecting posteriorly over the amplexial grove. Brood pouch transversely flattened, with a posterior fusiform projection, terminating at gonopore. Brood pouch extending to abdominal segment III. Dorsum of genital segment I with a dorsolateral spine. Dorsum of genital segment II with a dorsolateral lobe, directed posteriorly, and with an acute apex. Abdominal segments smooth and cylindrical. Cercopods as for genus.

Egg. spherical, diameter approximately 220 μm, with dense covering of conical denticles, approximately 10μm in diameter, nearly as broad as high.

Distribution and Habitat. Chirocephalus soulukliensis n. sp. is so far only known from the type locality: Soulukli wetland in Golestan National Park, Iran. Golestan National Park is an important conservation area. The Park is situated (37º 31' N – 56º 35' E) at the eastern end of Alburz mountains between the cities of Gonbad Qaboos and Bojnord and ranges from 380 m to 2411 m above sea level. Golestan National Park is an intergrate zone between the Hyrcanian and Irano-Touranian floristic regions, making this area biologically rich. The Park ranges from semiarid scrub in the east to humid forest in the west. Mean annual precipitation ranges between 140 mm in Dasht-e Kalpush, located in the south, and 870 mm in Minudasht, which may receive extended periods of fog. The steep slopes act as a barrier between the humid Hyrcanian air masses from the west, and the continental air masses from the east, resulting in high precipitation along the northern slopes of Alu-Baq and above the Qorqon rocks, more than 1000 mm /year (Akhani 2005).

There is no information about the invertebrate fauna in the Soulukli wetland, however botanical surveys have been conducted (Akhani 1998, 2005). Aquatic birds and mammals were observed using the site.

Figures

FIGURE 1. Map of Golestan National Park, depicting the location of Soulukli Wetland.

FIGURE 2. Chirocephalus soulukliensis n. sp., types: A) male, head, left anteriolateral view (scale bar = 0.7 mm) B) Female, right lateral view (scale bar = 2.0 mm). C) Gonopods, ventral view (right gonopod everted, left gonopod retracted) (scale bar = 2.2 mm). D) segments = 1.0 mm).