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Stylopallene tubirostris Clark, 1963 Material examined ( S 92305): 1 male (SHE0009), Bass Point, New South Wales, Nov- 28 2010, 20 m depth, on Amathia spp. Remarks: A common species in southern Australia. The characteristic styliform proboscis and the colouration markings on body and legs of this material from New South Wales agree with the original description of S. tubirostris in Clark (1963)., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on page 431, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene tasmania sp. nov. Figs. 3 D, 7 A���H Material examined: Holotype (J 4517): 1 female (PSE 4 a), Nov- 2009, Eaglehawk Neck, Tasmania, 5���20m depth on Orthoscuticella spp. Paratypes (S 92216): 2 females (PSE4, 4b) from same location as holotype; (S 92217): 2 sub-adults (TAS 21 a, 35 a), Jan- 26 2007, Waterfall Bay at Eaglehawk Neck, 21 m depth, in kelp forest. Diagnosis: Neck short, constricted; legs with no constrictions, femur thickest compared to distal segments, tibia 2 about 4 mm long, more slender than tibia 1; strigilis with very high number of compound spines, 68 in total, seventh article alone with 25 spines. Red-toned colouration of midgut when alive, losing colour after ethanol preservation. Sequence divergence from other Pseudopallene forms: 10 to 14 % in COI and 21 to 23 % in ITS. Description of female: Leg span 38 mm; body (Figs. 3 D; 7 A) fully segmented, glabrous, holotype with encrusting epibionts on cuticle giving rough appearance dorsally; body and legs pale yellow, cuticle semitransparent, red-coloured midgut with its diverticula seen through cuticle when live, not visible after preservation. Neck (Fig. 7 A,B) short, marked constriction, pre-ocular surface not divided, without mid-dorsal mound. Ocular tubercle (Fig. 7 A,B) as tall as wide, with dorsal papillae, eyes darkly pigmented. Abdomen (Fig. 7 A) as long as fourth lateral processes, not constricted distally or inflated, cleft anal opening. Lateral processes 1.5 times as long as wide, glabrous. Proboscis (Fig. 7 B,G,H) bullet-shaped, slightly inflated on distal section before tapering to mouth, no tuft of setae surrounding mouth. Cheliphore (Fig. 7 A,B,G) scape with constriction line proximally, not in male (Fig. 7 H), as long as proboscis; chela palm inflated, fingers short, about half of palm length, with linear, smooth cutting-edge, movable finger slightly shorter than immovable finger, touching immovable finger just before its tip, fingers leaving proximal gap when closed, no setae on chelae. Oviger fifth article longest, straight, compound spine formula: 25: 18: 15: 10 (Fig. 7 D), terminal claw margins not denticulated, only light crenulation on endal side (Fig. 7 C). Legs (Fig. 7 E,F,H) glabrous, with row of tiny, spare spinules dorsally and ventrally on major articles; third coxa twice as long as first; second coxa about three times as long as coxa 1; femur swollen compared to tibiae, subequal in length with tibia 2, eggs visible through cuticle; tarsus short, about 12 % of the propodus, one large tarsal spine aligned with heel spines on propodus; propodus straight, heel inconspicuous, four heel spines, two middle ones larger, eight sole spines; main claw nearly half the propodus length (Fig. 7 F). Measurements of female holotype in mm: body length = 3.31; body width = 1.87; abdomen length = 0.45; ocular tubercle height = 0.38; proboscis length = 1.14; chela fingers = 0.63; scape = 1.42; oviger 5 th article = 1.12, 10 th article = 0.34, claw = 0.16; 3 rd leg coxa 1 = 0.55, coxa 2 = 1.69, coxa 3 = 0.93, femur = 4.6, tibia 1 = 3.8, tibia 2 = 4.7, tarsus = 0.19, propodus = 1.23, claw = 0.51. Etymology: Species named after the type locality. Tasmania seems to harbour highly diverse Pseudopallene assemblages yet to be described. Noun in apposition. Remarks: When alive, these specimens were clearly distinct from other Pseudopallene specimens with their clear cuticle showing red midgut diverticula. This pattern of colouration has not been described before in the genus. Together with the high count of compound ovigeral spines (> 60 spines) and the inconspicuous propodal heel, these are unusual characters that segregate this new species from other known Pseudopallene. According to the molecular data, the species is highly divergent with more 10 % variation in the COI and 23 % in the ITS sequences compared to other local Pseudopallene species (Table 2)., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on page 417, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene flava sp. nov. Figs. 2 D, 3 A, 14 A���H Material examined: Holotype (J 4520): 1 male (PSE 1), Nov- 21 2009, Eaglehawk Neck, Tasmania, 5���20 m depth, on Orthoscuticella spp. Paratypes (S 92301): 1 sub-adult (PSE 1 a), 1 male (PSE 1 b), same location as holotype, other material from same location: (S 92302) 3 males, 3 females, 2 sub-adults, 1 male (GBTAS), Oct- 25 2008, Waterfall Bay, Eaglehawk Neck, 20 m depth, on bryozoans. Diagnosis: Large size, 40 mm leg span, glabrous, plain yellow, straight inflated proboscis narrowing just distally. Legs with no constrictions, shallow propodal heel, six heel spines, middle one largest. Terminal claw crenulated on both sides, ventral longitudinal groove distally. Sequence divergence from 8 to 14 % in COI and 3 to 23 % in ITS (Table 2). Description of male: Leg span 40 mm, uniformly yellow-coloured when live (Fig. 2 D). Body (Fig. 14 B,D) fully segmented, glabrous, smooth; lateral processes as long as wide; neck (Fig. 14 A,B) short, pre-ocular surface smooth, indistinct longitudinal cuticular division line, no mid-dorsal mound. Ocular tubercle short (Fig. 14 A,B), as tall as wide, with a pair of small dorsal papillae, four darkly pigmented eyes of equal size. Abdomen (Fig. 14 B) horizontal, not swollen, reaching distal margin of fourth lateral processes. Proboscis (Fig. 14 A) inflated, ending in a small narrow tip, without mid-point constriction. Cheliphore (Fig. 14 A���C) scape long, unconstricted, smooth, slightly longer than proboscis; chela longer than scape, palm inflated, fingers shorter than palm, of equal length; movable finger slightly curved, with small midpoint bump on cutting edge; wide gap when fingers touch at tip. FIGURE 14. Pseudopallene flava sp. nov., male holotype (J 4520) A, frontal view; B, lateral view. Note absence of mid-dorsal cephalic mound; C, detail of chelae, ventral view, distal oviger articles at the bottom; D, dorsal view, some legs in complete view; E���F, female paratype (S 92302); E, third leg; F, propodus and terminal claw of third walking leg; G, distal oviger articles including terminal claw; H, oviger articles 4 to 10, male distal apophysis visible on 5 th article. Scale bars on stereomicroscopic images = 1 mm or as shown. Oviger���s (Fig. 14 G,H) fifth article longest, slightly curved, with distal apophysis, two-thirds of article diameter; four distal-most articles decrease in size distally; oviger compound spine formula: 20: 12: 12: 10. Terminal oviger claw margins crenulated, crenulation along total length endally, along half its length ectally, longitudinally folded on ventral side forming a groove. Leg (Fig. 14 D���F) articles uniform in thickness, smooth, tiny spinules seen under high magnification; coxa 2 almost 2.5 times as long as coxa 1; femur curved, longer than tibia 1; tibia 2 longest article; tarsus short, with one large ventrodistal spine aligned with heel spines; propodus with protruding but not too prominent heel; four to five large, subequal heel spines; main claw length about 60 % of propodus length. Measurements of male holotype male in mm: body length = 4.22; body width = 2.46; abdomen length= 0.59; ocular tubercle height = 0.27; proboscis length = 1.48; scape = 1.70; palm = 1.05; chela fingers = 0.80; oviger 5 th article = 2.68, 10 th article = 0.41, claw = 0.24; 3 rd leg coxa 1 = 0.65, coxa 2 = 1.71, coxa 3 = 0.76, femur = 4.72, tibia 1 = 3.76, tibia 2 = 5.19, tarsus = 0.27, propodus = 0.90, claw = 0.57. Etymology: The species epithet ���flava��� means ���yellow��� (latin, fem.) describing the bright, uniform yellow colouration of the specimens that contrasts with their dark orange-red bryozoan host. Remarks: P. f l a v a is the largest species found in the Tasmanian material. Although similar in overall body size and colouration to P. ambigua, it differs strikingly from the latter in proboscis and especially chela shape. Owing to the lack of a mid-point constriction of the proboscis, even the smaller sub-adult specimens of P. f l a v a can be easily distinguished from the slightly smaller sympatric P. constricta, which is also uniformly yellow in life. Compared to P. f l a v a, the Tasmanian specimens of the Pseudopallene ���variabilis��� -complex (see next paragraph) are significantly smaller and of more slender appearance. Female specimens show a slight basal constriction of the cheliphore scape as in other callipallenid species (see Discussion)., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on pages 426-428, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene gracilis sp. nov. Figs. 3 F, 11 A���G Material examined: Holotype (J 4518): 1 male (PSE 6), Nov- 24 2009, Fog Rock, Eaglehawk Neck, Tasmania, 10���17 m depth, on bryozoans. Diagnosis: Legs long, slender, spinose, with no constrictions; ocular tubercle tall; proboscis and cheliphores directed slightly anteroventrally, rather than posteroventrally; straight proboscis with distal tuft, narrow tip; chelae fingers straight, without conspicuous proximal gap when closed. Body and legs orange with yellow-tinted bands when alive (no photograph available). Sequence divergence from other Pseudopallene forms is 11 to 14 % in COI and 19 to 24 % in ITS (Table 2). FIGURE 11. Pseudopallene gracilis sp. nov., male holotype (J 4518). A, dorsal view showing proximal leg articles; B, frontal view, note dark tuft surrounding mouth; C, detail of chelae; D, oviger articles, 5 th article with prominent distal apophysis; 7 th��� 9 th articles with compound spines; E, second leg; F, detail of distal-most oviger articles including terminal claw; G, propodus and terminal claw of third walking leg. Scale bars on stereomicroscopic images = 1 mm or as shown. Description of male: Leg span 30 mm, slender appearance, orange colouration when alive. Body (Fig. 11 A) fully segmented, neck distinct, with ovigers attaching laterally, raised mid-dorsal mound on pre-ocular surface, longitudinal cuticular division line not seen dorsally, only a fine line at mid-point between cheliphore insertions in frontal view. Ocular tubercle (Fig. 11 A,B) tall, twice its width at base, slightly inclined backwards, with prominent distal papillae; four darkly pigmented eyes, anterior pair larger. Lateral processes longer than wide, width 83 % of length, smooth; abdomen as long as fourth lateral process, swollen distally, cleft anal opening. Proboscis (Fig. 11 B,C) directed ventrally, slender, straight, without mid-point constriction, distally narrowing to mouth surrounded by dark tuft of setae. Cheliphore (Fig. 11 B,C) scapes as long as proboscis, directed slightly anteroventrally, slender, hint of constriction line near the base; chelae short, 81 % of scape length, glabrous; palm inflated but not globose; fingers as long as half of palm length, with linear cutting edge leaving only a narrow gap when closed. Oviger fifth article longest, curved, with prominent apophysis distally (Fig. 11 D); fourth article with much smaller, rounded distal apophysis; oviger spine formula 13: 9: 6: 7 (Fig. 11 D); terminal claw with strong denticulations on both margins in distal half, longer denticulated margin endally (about 31 denticulations) (Fig. 11 F). Legs (Fig. 11 E,G) long, about seven times as long as the trunk, slender, with two or three rows of sparse short spinules dorsally and ventrally on major articles; tibia 2 longest article; femur curved, second longest article; tarsus short, typical, with small distal spine in line with heel spines; propodus straight, propodal heel not conspicuous, six heel spines, gradually increasing in size; 12 sole spines; main claw longer than half of propodus length. Measurements of male holotype in mm: body length = 2.28; body width = 1.45; abdomen length = 0.35; ocular tubercle height = 0.39; proboscis length = 1.06; chela fingers = 0.53; scape = 1.15; oviger 5 th article = 1.21, 10 th article = 0.23, claw = 0.16; 3 rd leg coxa 1 = 0.48, coxa 2 = 1.35, coxa 3 = 0.7, femur = 3.3, tibia 1 = 3.02, tibia 2 = 3.51, tarsus = 0.19, propodus = 0.88, claw = 0.48. Etymology: The species name relates to the slender, graceful habitus of this long-legged Pseudopallene species. Remarks: The comparably short and slender chelae and the relatively long and slender leg articles (including coxa 2), and the short spinules on the legs, giving it a spiky appearance, serve to distinguish this medium-sized individual from previously described species. The new species shows a prominent tuft surrounding the mouth. The narrow, folded terminal oviger claw with numerous sharp denticulations all around the ectal and endal margins are characteristic of the species., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on pages 420-422, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene constricta sp. nov. Figs. 2 B, 3 B, 12 A–F Material examined: Holotype (J 4519): 1 male (PSE 2), Nov- 2009, Eaglehawk Neck, Tasmania, 5–20 m depth, on Orthoscuticella spp. Paratypes (S 92223): 4 males (including PSE 2 a), 3 females (including PSE 2 b), 2 postembryonic stages (PSE 10, PSE 10 a); all from the same location as holotype. Diagnosis: Medium-sized species; uniformly yellow when live; marked constriction of proboscis at mid-point, chela fingers straight, tips weakly or distinctly crossing when closed, leaving a narrow proximal gap in between, femora curved, legs slender, with no constrictions, with rows of nodulose, short spines giving ‘prickly’ appearance to legs under high magnification; prominent propodal heel with four stout heel spines. Sequence divergence ranges from 10 to 13 % in COI and 6 to 23 % in ITS. Description of male: Leg span 32 mm, live colouration uniform bright yellow on body and legs. Body (Fig. 12 A,C) fully segmented; neck about 0.5 mm long, parallel sides in between the ovigers insertion and the constriction between the neck and a laterally expanded cephalon; cephalon without conspicuous pre-ocular middorsal mound, or longitudinal cuticular division line. Ocular tubercle (Fig. 12 A,C) as wide as tall, with only weakly protruding dorsal papillae; four small, darkly pigmented eyes, all of equal size. Lateral processes (Fig. 12 C) 1.25 as long as wide, glabrous, separated by about one-quarter of their basal diameter. Abdomen (Fig. 12 C) straight, overreaching the distal margin of the fourth lateral processes. Proboscis (Fig. 12 A,B) directed ventrally, with conspicuous mid-point constriction, somewhat inflated in distal part, tapering to oral tip, mamilliform, no tuft of setae visible. Cheliphore (Fig. 12 A,B) scape one-articled, indistinct proximal constriction, as long as proboscis. Chelae robust, outer surface of palm inflated, spare minute spinules; fingers subequal in length, 80 % of palm length, finger tips cross when closed, leaving proximal gap, immovable finger with straight cutting edge, movable finger slightly curved. Oviger (Fig. 12 F) fifth article longest, with distinct apophysis distally; strigilis articles subequal, spine formula 12: 6: 6: 6; terminal claw ~ 70 % of tenth article length, acute, endal margin denticulate, only distal half of ectal margin denticulate. Legs (Fig. 12 D,E) 4.3 times as long as body, with minute spines arranged in longitudinal rows. Second coxa 2.5 as long as subequal first and third; femur curved; tibia 1 distally swollen, shorter than femur; tibia 2 straight, longest article; tarsus typical, with one main distal spine, covered in tiny setae; propodus curved, prominent heel with row of four stout spines, two middle ones larger; sole with median row of 14–15 small spines. Main claw long, nearly 70 % of propodus length. Genital pores on second coxae of third and fourth leg pairs. Measurements of male holotype in mm: body length = 3.32; body width = 1.96; abdomen length = 0.53; ocular tubercle height = 0.32; proboscis length = 1.18; scape = 1.19; chela fingers = 0.57; oviger 5 th article = 1.16, 10 th article = 0.27, claw = 0.13; 3 rd leg coxa 1 = 0.58, coxa 2 = 1.72, coxa 3 = 0.67, femur = 3.13, tibia 1 = 2.73, tibia 2 = 3.42, tarsus = 0.23, propodus = 1.03, claw = 0.68. Etymology: The species name refers to the characteristic constriction of the proboscis, which serves to readily distinguish this species from similarly coloured, sympatric congeners. Remarks: Previously, Stevenson (2003) in his MSc thesis investigated specimens of this form, which had been collected at the same sampling site. In accordance with the present study, he found morphological as well as molecular evidence (16 S rDNA and COI fragments) in support of its valid species status, without, however, presenting a formal species description. Recent studies (Brenneis et al. 2011 a, b) have focussed on the development of the yellow Pseudopallene species from Tasmania. The investigation of post-embryonic development was conducted on the transparent-yellowish post-embryonic stages that have been clearly assigned by the molecular data to P. constricta sp. nov. (see Brenneis et al. 2011 b for morphological description of postembryonic stages). During the collection period (second half of November), all yellow Pseudopallene species encountered in the study area did carry eggs. Yet, in P. constricta, they were observed to be generally in later developmental stages, males often bearing already hatched post-embryonic stages 1 and 2. This might be indicative of a slight shift in the reproductive periods of the sympatric Pseudopallene species.

Pseudopallene pachycheira (Haswell, 1885) Figs. 2 F, 3 H, 10 A���D Material examined: (S 92220) 1 female (PSE 8), 1 sub-adult (PSE 11 a), on Orthoscuticella spp., Nov- 24 2009, Fog Rock, Eaglehawk Neck, Tasmania, 10���17 m depth; (S 92222) 1 sub-adult (TAS 21), Jan- 26 2007, in kelp forest, Fortescue Bay, Eaglehawk Neck, Tasmania, 21 m depth. Remarks: This species is easily recognised by the distinct constrictions on the three longer leg articles (Fig. 10 C). The chela fingers are short and stout, the movable finger with a mid-point lobe on the cutting edge (Fig. 10 B). The cephalon shows a clear longitudinal division in frontal view (Fig. 10 A) and the propodus is curved with six large heel spines and a long terminal claw (Fig. 10 D). Interestingly, the live female specimen showed a yellow colouration with an orange banding pattern on body and legs (Fig. 2 F), which seems to deviate from the orangebrownish colouration previously reported (Staples 1997, 2008)., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on page 420, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene reflexa (Stock, 1968) Figs. 3 E, 8 A���D Material examined: (S 922218) 1 female (PSE 5 a), 2 males (PSE5, 5b), 1 sub-adult (PSE 11), Nov- 2009, Eaglehawk Neck, Tasmania, on Orthoscuticella spp., Boulder Point, 5���10 m depth. Remarks: This species is readily distinguished by the undivided pre-ocular surface (Fig. 8 A), the irregular surface of the longer leg articles (Fig. 8 B) and the prominent propodal heel with paired heel spines arranged in a Vshape (Fig. 8 D). The Tasmanian material is in good agreement with the description of specimens from South Australia and Victoria regarding the shape of abdomen and proboscis, the oviger spine formula: 14: 9: 9: 8, the terminal oviger claw (Fig. 8 C), and the orange colouration (Staples 2005). Judging from some of the drawings in Stevenson (2003) (especially his fig. 16, p. 39), he might have already investigated P. re fl ex a specimens from Eaglehawk Neck, Tasmania, but erroneously assigned them to P. pachycheira. The irregular surface on the legs of P. re f l e x a might be confuseded with the more regular leg constrictions in P. pachycheira when small individuals (e.g. sub-adults) are only casually examined by the naked eye., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on page 417, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Stylopallene Clark 1963 Stylopallene cheilorhynchus Clark, 1963 Fig. 2 I Material examined (S 92304): 2 males, 4 females (Tas 11 - 6), Waterfall Bay, Eaglehawk Neck, Tasmania, Jan- 25 2007, 20 m depth, on Amathia wilsoni. Remarks: A common species in southern Australia. Our Eaglehawk Neck material agrees with the original description in Clark (1963) based on specimens from the nearby Port Arthur. It also agrees with descriptions in subsequent studies (Staples 2005; Bamber 2005; Bamber & Takahashi 2005)., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on page 430, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene brevicephala Staples, 2008 Figs. 2 E, 3 G, 9 A���D Material examined: (S 922219) 1 sub-adult (TAS 28), 26 Jan 2007, Fortescue Bay, 21 m depth in kelp forest; 1 female (PSE 7), 1 male (PSE 7 a), 2 sub-adults (PSE 7 b, PSE 12), (S 92221) 2 post-embryonic stages (PSE 12 a, b) (no DNA available), Nov- 26 2009, Patterson Arch, Eaglehawk Neck, 10���15 m depth, on Orthoscuticella spp; 3 postembryonic stages (PSE 9, PSE 9 a, b), Nov- 22 2009, Boulder Point, 5���10 m depth. Remarks: The adult morphology of the Tasmanian specimens corresponds to the species description based on material from South Australia (Staples 2008), especially the diagnostic short neck (Fig. 9 A), the distinct longitudinal cuticular division line on the cephalon (Fig. 9 B), the oviger compound spine count (8: 7: 6: 6 in specimen PSE 7) (Fig. 9 C) and the propodus configuration (Fig. 9 D). One character to add to the description of the species is the uniform red-orange colour on body and legs in live adults, sub-adults and post-embryonic stages at least for the Tasmanian specimens (Fig. 2 E). Clark (1963) described P. dubia based on material from Port Arthur, Tasmania, with different types of chela shapes. Some specimens had a characteristic delicately-curved tube-like elongation of the movable finger, whereas others were lacking this feature. Staples (2005) already proved the P. dubia specimens to represent late developmental stages of Pseudopallene rather than fully grown adults, without assigning them to a species. So far, post-embryonic stages of different Pseudopallene species have been shown to exhibit the tube-like projection of the movable chela finger, e.g., in P. watsonae Staples, 2005 or in P. constricta sp. nov. (see below, see also Brenneis et al. 2011 b). A detailed morphological description of our genetically identified orange-red post-embryonic stages of P. brevicephala from Tasmanian is still underway. However, first observations have shown that the movable chela finger of these individuals lacks the distal tube-like extension, similar to some of the specimens investigated by Clark (1963). This strongly indicates that (1) Clark confounded developmental stages of different species, his material probably including P. brevicephala besides other congeners and that (2) those post-embryonic stages having been cautiously assigned to P. brevicephala by Staples (2008) might in fact belong to another species, since they exhibit the distinctive tube-like elongation of the movable chela finger. This is the first record of P. brevicephala from Tasmania., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on page 418, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Pseudopallene harrisi sp. nov. Figs. 2 G, 13 A���F Material examined: Holotype (P. 90044): 1 female (SHE010), Nov- 29 2009, Bass Point, New South Wales, 20 m depth, on bryozoans and hydroids. Paratypes (S 92225): 1 ovigerous male, 1 male (SHE010- 1) from the same location. Diagnosis: Large size, 50 mm in leg span, red body with dorsally chalky bright yellow lateral processes and cheliphore bases, legs with no constrictions, predominantly red, coxa 3 and distal sections of femur and both tibiae with same bright yellow colouration. Massive chelae, fingers short, stout; propodus with four large heel spines decreasing in size proximally. Sequence divergence from 10 to 14 % in COI and 6 to 23 % in ITS when compared to other congeneric species for which these DNA fragments were available. Description of female: Leg span 50 mm. Body (Fig. 13 A) smooth, glabrous, fully segmented, when alive coloured dark red with ocular tubercle, lateral processes, third coxae and pre-ocular surface at the base of cheliphores coloured bright yellow, also wide yellow bands distally on major leg articles (Fig. 2 G); colouration disappears after ethanol preservation. In holotype, neck relatively long, with parallel sides, with round mid-dorsal mound, longitudinal cuticular division line arising from anterior margin, especially clear in frontal view (Fig. 13 C). Ocular tubercle (Fig. 13 A,C) as tall as wide, with dorsolateral papillae, slightly inclined backwards, four darkly pigmented eyes, posterior pair slightly larger. Lateral processes (Fig. 13 A) almost twice as long as wide, well separated, at least by half their diameters. Abdomen horizontal, as long as fourth lateral processes. Proboscis (Fig. 13 B,C) conical, distally tapering to a narrow mouth, with dark marks on distal narrow portion seen after preservation. Cheliphores (Fig. 13 A-C) robust, scape and palm subequal in length, palm inflated giving massive globose appearance; fingers short, half length of palm, movable finger clearly curved, with mid-point lobe on thick, darker cutting edge; immovable finger longer than movable finger, also thick and dark on cutting margin; proximal gap seen when fingers closed. Oviger (Fig. 13 E,F) fifth article longest, curved, with distal, round apophysis; oviger compound spine formula 16: 13: 11: 11 (Fig. 13 E); terminal claw slightly shorter than tenth article (Fig. 13 E), curved, with eight denticulations on distal half of ectal margin, at least 18 denticulations along endal margin and tip (Fig. 13 F). Legs (Fig. 13 A,D) long, about 4.5 times the body length, slender, covered in tiny spinules from coxae to propodus, coxa 2 more than twice the length of coxa 1, tibia 2 longest article followed by femur and tibia 1. Tarsus short, typical, with ventral spines, largest surrounded by short, thick spines; propodus straight, inconspicuous heel, four heel spines, most distal largest, other three decreasing in size proximally; main claw longer than half of the propodus length. Measurements of female holotype in mm: body length = 5.35; body width = 3.20; abdomen length = 0.76; ocular tubercle height = 0.39; proboscis length = 1.63; chela fingers = 0.95; scape = 1.62; oviger 5 th article = 1.55, 10 th article = 0.45, terminal claw = 0.25; 3 rd leg coxa 1 = 0.79, coxa 2 = 1.91, coxa 3 = 1.0, femur = 5.45, tibia 1 = 5.24, tibia 2 = 6.85, tarsus = 0.35, propodus = 1.40, claw = 0.75. Etymology: The species is named after Mick Harris, an experienced diver and pycnogonid enthusiast who contributed with the collecting and photography of these specimens and greatly supported the field logistics at Shellharbour in November 2009. Remarks: Of all investigated species in this study, P. harrisi shows the closest resemblance to the P. ambigua holotype and the P. ambigua specimens deposited in Museum Victoria. This holds especially for the relative size and proportions of the chelae (compare Fig. 13 B, C and Fig. 16 A, B). However, the even larger overall body size and slightly more robust general appearance as well as the oviger configuration with more spines and denticulations on the terminal claw set P. h ar r is i aside from P. ambigua. Additionally, the very distinctive body colouration pattern of P. harrisi is significantly different from the reported predominantly yellow live colouration of P. ambigua (Staples 1997, 2007). Notably, Clark (1963) in his cautious description of putative P. ambigua material from the collection of the Australian Museum, Sydney, mentions similar red and yellow live colouration of a single medium-sized immature specimen from NSW. Detailed re-examination of the many Pseudopallene specimens collected along the New South Wales coast over the years may reveal that P. harrisi is represented in the Australian Museum collection. In terms of size, the big and robust P. laevis (Hoek, 1881), which has been described on the basis of a single female specimen from the Bass Street, is similar to P. ambigua and P. harrisi. However, since the location of the P. laevis holotype is currently unknown, its re-investigation was not possible. Due to this unfortunate circumstance and the different geographic location of both forms, we decided to set P. harrisi apart from P. l a e v i s., Published as part of Arango, Claudia P. & Brenneis, Georg, 2013, New species of Australian Pseudopallene (Pycnogonida: Callipallenidae) based on live colouration, morphology and DNA, pp. 401-436 in Zootaxa 3616 (5) on pages 424-426, DOI: 10.11646/zootaxa.3616.5.1, http://zenodo.org/record/220125

Diese Arbeit befasst sich mit der Entwicklung der Asselspinne Pseudopallene sp. (Arthropoda, Pycnogonida). Die Morphogenese und Nervensystementwicklung werden mithilfe von Rasterelektronenmikroskopie, Histologie, Immunhistochemie und Genexpressionsstudien untersucht. Während der Proboscisbildung lassen sich keine Anzeichen für ein Labrum erkennen. Aufgrund des Fehlens von Palpen- und Ovigeranlagen und der frühen Entwicklung der Laufbeinsegmente ist kein embryonales Protonymphon-Stadium identifizierbar. Die Evolution verschiedener Larvenformen der Pycnogoniden wird im Hinblick auf phylogenetische Studien diskutiert. Die frühen Prozesse im Neuroektoderm zeigen Ähnlichkeiten zu Eucheliceraten und Myriapoden. Hierzu zählen das Fehlen morphologisch distinkter Zelltypen, die Bildung von Zellinternalisierungszentren, die Immigration vorwiegend post-mitotischer Ganglionzellen mit erhöhter Delta-Genexpression und fast ausschließlich tangentiale Zellteilungen. Anschließend bilden sich pro Neuromer ein Paar Invaginationen, was durch Vergrößerung der apikalen Zellen begleitet wird. Letztere sind aufgrund ihrer hohen Mitoseaktivität, ihres asymmetrischen Teilungsmodus und des anhaltenden Zuwachses der basalen Ganglionzellen als stammzellartige neuronale Vorläuferzellen identifizierbar. Hierauf basierend wird die Validität von stammzellartigen neuronalen Vorläuferzellen als Synapomorphie der Krebse und Insekten diskutiert. Zwei evolutionäre Szenarien zur Arthropoden-Neurogenese werden erörtert. In der post-embryonalen Phase lösen sich die invaginierten Zellregionen vom Ektoderm ab. Sie bilden apikal auf den Ganglien paarige Zellcluster und bleiben mit deren Somacortex über fibrilläre ‚cell streams‘ verbunden. Der weitere Zuwachs an Ganglionzellen und die exklusive Zellproliferation in den cluster-stream-Systemen weisen letztere als post-embryonale neurogenetische Nischen aus. Ähnlichkeiten zu der neurogenetischen Nische im Deutocerebrum der decapoden Krebse werden aufgezeigt. This study addresses aspects of the development of the sea spider Pseudopallene sp. (Arthropoda, Pycnogonida). In order to investigate morphogenesis and nervous system development, a combination of scanning electron microscopy, histology, immunohistochemistry and gene expression studies is used. Embryonic proboscis development shows no signs of a labrum. The lack of palpal and ovigeral limbs and the early anlagen of the walking leg segments lead to the rejection of an embryonized protonymphon stage during Pseudopallene development. The evolution of pycnogonid hatching stages is evaluated in light of recent phylogenetic analyses. Early neurogenesis shares similarities with euchelicerates and myriapods, including the lack of morphologically distinct neuroectodermal cell types, formation of transient cell internalization sites, immigration of mostly post-mitotic ganglion cells with elevated levels of Delta gene expression and predominantly tangentially oriented cell divisions in the neuroectoderm. Subsequently, paired invaginations form in each neuromere, being accompanied by marked enlargement of the apical cells. Due to their high mitotic activity, their asymmetric division mode and a marked cell number increase in the ganglia, the big cells are identified as stem cell-like neuronal precursors. Based on this, the validity of stem cell-like neuronal precursors as synapomorphy of crustaceans and hexapods is discussed. Two scenarios on the evolution of arthropod neurogenesis are presented. During the post-embryonic phase, the invaginating cell regions detach internally and form paired cell clusters at the apical ganglion sides. Each cluster remains connected to the ganglion soma cortex via fibrous cell streams. Increasing ganglion cell numbers and exclusive occurrence of mitoses within the cluster-stream-systems characterize the latter as post-embryonic neurogenic niches. Similarities to the neurogenic niche in the deutocerebrum of decapod crustaceans are discussed.