Glabrithelphusa angene, Meyer, Kirstin S., Cumberlidge, Neil & Koppin, Jennifer C., 2014
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publication ID |
https://doi.org/ 10.11646/zootaxa.3884.1.5 |
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publication LSID |
lsid:zoobank.org:pub:0DFB8B35-C265-4E96-876A-3B9BB051DF57 |
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DOI |
https://doi.org/10.5281/zenodo.6139267 |
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persistent identifier |
https://treatment.plazi.org/id/A9132D0C-FFF4-A116-25B8-DE39FA34FC82 |
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treatment provided by |
Plazi |
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scientific name |
Glabrithelphusa angene |
| status |
sp. nov. |
Glabrithelphusa angene , n. sp.
( Figs 1–4 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 )
Material examined. MADAGASCAR. Adult male holotype by present designation (cw 41.5, cl 29.3, ch 15.3, fw 12.4 mm), no locality or collection information (MNHN-IU-2013-11978). Paratypes: 4 adult males (cw 40.4, cl 29.0, ch 14.9, fw 11.3 mm; cw 37.4, cl 27.9, ch 15.1, fw 10.6 mm; cw 45.4, cl 32.7, ch 17.0, fw 13.0 mm; cw 43.6, cl 31.8, ch 16.6, fw 12.3 mm), 3 adult females (cw 36.9, cl 28.6, ch 16.7 fw 10.8 mm; cw 36.5, cl 27.6, ch 14.8, fw 10.6 mm; cw 39.2, cl 28.4, ch 14.9, fw 10.5 mm) (MNHN-IU-2013-11979), same data as holotype.
Type locality. Madagascar. Exact locality and habitat unknown.
Distribution. Only known from Madagascar.
Diagnosis. As for genus.
Description (based on holotype, adult male cw 41.5 mm). Carapace ( Fig. 1 View FIGURE 1 A, 3A) outline transversely oval, high (ch/fw 1.34); front narrow (fw/cw 0.27), deflexed; epibranchial, exorbital teeth small, low; space or cleft between epibranchial tooth and exorbital tooth reduced to small but distinct shallow notch; anterolateral margin evenly curved outward, completely smooth. Postfrontal crest faint, incomplete, postorbital crests, epigastric crests poorly defined, positioned well forward almost in line with postorbital margins; short, broad shallow mid-groove between epigastric crests; cardiac, urogastric grooves shallow, cervical grooves faint, short ( Fig. 1 View FIGURE 1 A, 3A). Entire dorsal surface of carapace smooth ( Fig. 1 View FIGURE 1 A, 3A). Suborbital, subhepatic regions of carapace sidewall completely smooth, pterygostomial region with fields of carinae near buccal margin, fading to smooth posteriorly; vertical sulcus on carapace sidewall curved, raised, faintly granular, running from base of epibranchial tooth to epimeral sulcus ( Fig. 1 View FIGURE 1 B, 3C). Epimeral sulcus heavily granular between suborbital, anterior pterygostomial regions, smooth posteriorly. Epistomial tooth triangular, deflexed, edges smooth ( Fig. 1 View FIGURE 1 B, 3C). Third maxilliped exopod long, reaching beyond ischium/merus junction, exopod flagellum long reaching beyond superior margin of third maxilliped merus; ischium with deep, wide vertical sulcus ( Fig. 1 View FIGURE 1 C, 3B,C). Mandibular palp 2-segmented with small, hard, anterior lobe at junction between segments, 0.25x length of terminal segment ( Fig. 2 View FIGURE 2 D,E). Sternal sulcus s1/s2 short, very faint; sternal sulcus s2/s3 completely crossing sternum; sternal sulcus s3/s4 reduced to 2 short, deep notches at margins ( Fig. 2 View FIGURE 2 F, 3B); anterior sternoabdominal cavity smooth, lacking dense setae ( Fig. 2 View FIGURE 2 F, 3B). Episternal sulci s4/e4, s5/e5, s6/e6, s7/e7 absent, smooth ( Fig. 2 View FIGURE 2 F, 3B). Male abdomen slim, triangular, tapered, widest at a3, narrowest at a7 (telson); telson outline forming triangle with rounded apex, straight sides, broad base ( Fig. 2 View FIGURE 2 F, 3B). Sternal groove s4/s5 meeting a7 well past a6/a7 junction; sternal groove s6/s7 close to a6/ a7 junction, meeting a6 3/4 of segment length from a6/a5 ( Fig. 2 View FIGURE 2 F, 3B).
G1 terminal article short (length of terminal article to subterminal segment ratio 0.23), slim, with short setae, tapering to broad tip, directed outward, straight; medial fold on ventral terminal article raised; lateral fold not raised, folds basally separated, meeting midway along ventral face of article to form longitudinal groove that continues to tip of article; groove not visible on dorsal face; distal third of subterminal segment of G1 slim, curving outward for short distance near junction of terminal article with subterminal segment, with raised rounded shoulder on subterminal segment external margin ( Fig. 2 View FIGURE 2 AB, 4A,B,C,D). Junction between G1 terminal article, subterminal segment clearly visible on ventral side. G1 terminal article, subterminal segment separated on dorsal side by broad, subtriangular dorsal membrane; dorsal membrane superior margin formed by horizontal basal margin of terminal article, inferior margin of membrane formed by U-shaped distal edge of subterminal segment; lateral, medial margins of dorsal membrane narrow ( Fig. 2 View FIGURE 2 B, 4A,C,). G1, G2 subterminal segments equal in length, but G2 terminal article twice as long as G1 terminal article ( Fig. 2 View FIGURE 2 C, 4E). G2 terminal article long, well-developed, straight, no distal curve, one-half length of G2 subterminal segment ( Fig. 2 View FIGURE 2 C, 4E).
Dactylus of both chelipeds relatively slender, approximately one-third height of palm, cutting edge lined by small, even teeth; upper margin of dactylus smooth; lower margin of propodus slightly indented ( Fig. 1 View FIGURE 1 F,G). Fixed finger of propodus of major (right) cheliped slender with 3 unfused molars in proximal region followed by series of small pointed teeth ( Fig. 1 View FIGURE 1 F). First carpal tooth on inner margin of cheliped carpus large, pointed; second carpal tooth smaller, pointed, followed by series of very small teeth ( Fig. 1 View FIGURE 1 D). Medial, lateral, margins of inferior face of cheliped merus smooth, inferior face with small pointed, distal meral tooth; superior margin, superior face of cheliped merus smooth; cheliped ischium rounded, smooth ( Fig. 1 View FIGURE 1 D,E). Walking legs p2‒p5 normal length, not elongated (p5 merus/cw = 0.32), inner margins of propodi of p2‒p5 smooth ( Fig. 3 View FIGURE 3 A,B).
Remarks. The new species is distinguished from other species of Madagascan freshwater crabs by a unique suite of characters of the mandible, carapace, and gonopods (see Remarks for genus). The specimens described here are morphologically closest to the three species of the genus Foza ( Reed & Cumberlidge 2006; Cumberlidge & Meyer 2009). Glabrithelphusa angene n. sp. can be distinguished from these by its completely smooth dorsal carapace ( Fig. 1 View FIGURE 1 A, 3A) (versus strong carinae on the posterior dorsal carapace in F. raimundi and F. goudoti ( Reed & Cumberlidge 2006 Fig. 1 View FIGURE 1 B; Cumberlidge & Meyer 2009)), by granules on the anterolateral carapace surface in F. ambohitra Cumberlidge & Meyer 2009 Table 1), and by its mandible with a shortened anterior lobe, 0.25x terminal segment length ( Fig. 1 View FIGURE 1 D,E) (versus a mandible with a large anterior lobe, 0.5x terminal segment length ( Reed & Cumberlidge 2006; Cumberlidge & Meyer 2009)).
Etymology. The specific name angene is a combination derived from the names of the first author’s parents (Angela and Gene Meyer) used as a noun in apposition and is in recognition of their contributions to her education.
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.