Strumigenys fellowesi, Tang & Guénard, 2023

Tang, Kit Lam & Guénard, Benoit, 2023, Further additions to the knowledge of Strumigenys (Formicidae: Myrmicinae) within South East Asia, with the descriptions of 20 new species, European Journal of Taxonomy 907, pp. 1-144 : 57-60

Strumigenys fellowesi sp. nov.

urn:lsid:zoobank.org:act:6B9495DB-3694-4693-BA17-59280276C73E

Fig. 19 ; Tables 2 , 7

Diagnosis

Strumigenys fellowesi sp. nov. can be distinguished from other species in the S. godeffroyi -group by a combination of the following characters: mandible slightly tapered distally, preapical tooth very close to apical fork of mandible; apicoscrobal seta and pronotal humeral seta flagellate; cephalic dorsum, promesonotal dorsum, petiolar node, disc of postpetiole and gaster with decumbent to erect spatulate to subspatulate setae; pronotal dorsum and side of mesosoma mostly smooth and shining; dorsum of petiolar node fully sculptured; propodeal spines subtended by broad lamellae; petiolar node high, with differentiated anterior face, not claviform; dorsal surface of femur without any erect seta; hind tibiae and basitarsi with long projecting flagellate setae.

Etymology

The species is named after Dr John R. Fellowes in recognition of his excellent early work on ants in South China, and his generosity in providing us his collection that led to the recognition of this new species. The name was created by adding the singular Latin genitive case suffix -i to the last name of a male person.

Type material

Holotype worker ( Fig. 19 )

CHINA • Guangxi Province, Jiuwanshan , JWS136; 25 Jul. 1998; J. Fellowes leg.; “STRUM cf#5(25. vii.98) JWS136” [original label]; LKCNHM ANTWEB1011894 (collection code IBBL JF0020 ).

Paratype worker

MAINLAND CHINA • 1 worker; same collection data as for holotype; HKBM ANTWEB1011893 (collection code IBBL JF0020 ) .

Measurements

Holotype worker

TL 3.5, HL 0.80, HW 0.52, MandL 0.31, SL 0.54, EL 0.078, PW 0.32, ML 0.96, PL 0.39, PH 0.18, DPW 0.16, PPL 0.23, GL 0.78, CI 65, MI 39, SI 104, OI 15, LPI 46, DPI 40.

Paratype worker

TL 3.5, HL 0.79, HW 0.53, MandL 0.32, SL 0.54, EL 0.071, PW 0.32, ML 0.95, PL 0.37, PH 0.19, DPW 0.16, PPL 0.25, GL 0.83, CI 68, MI 41, SI 101, OI 13, LPI 50, DPI 43 (n=1).

Worker description

HEAD. In full-face view, occipital margin evenly, deeply concave; occipital corners well developed and bluntly angular; preocular lamina wide; posterior clypeal margin well-defined, converged at midpoint at an angle slightly smaller than a right angle; anterior clypeal margin mostly transverse. Mandible curvilinear but slightly tapered distally, with an elongated preapical tooth located very close to the apicodorsal tooth, hence superficially resembles a mandible with three apical teeth; the preapical tooth distinctly longer than the width of mandible at the point where the tooth arises; apicodorsal tooth markedly longer than apicoventral tooth, with 2– 3 intercalary denticles ( Fig. 19B ). Scapes subcylindrical, marginated but not converging anteriorly to form a thin lamella at the leading edge; apical antennomere unconstricted basally, about as long as the mandible. In profile view, eye with 3–4 ommatidia in diameter.

MESOSOMA. In profile view, promesonotal dorsum broadly convex; propodeum more or less flat transversely, anterior part of propodeum with small bump; pronotum not marginated dorsolaterally. In dorsal view, lateral margins of pronotum evenly convex. Propodeal teeth present but inconspicuous, subtended on each side by broad lamella that broadens basally into rounded convex propodeal lobe. Metapleural gland bulla well developed.

METASOMA. In profile view, petiolar node high, with dome-shaped outline and steep anterior face differentiated from peduncle; petiolar peduncle about as long as (or slightly longer than) node. In dorsal view, petiolar node about as broad as long (or slightly longer than broad); disc of postpetiole broader than long, around 1.3–1.4 times as long. Areolate processes (spongiform tissues) present on both petiole and postpetiole; ventral lobes of petiole and postpetiole extensive; lateral lobe of petiole merely small flap at posterolateral angle of node in profile and not reaching midpoint of node; anterior face of node with inconspicuous strip; in dorsal view, the processes present along lateral and posterior margins of petiolar node, and surrounding disc of postpetiole, thicker along lateral and posterior margins than on anterior margin.

PILOSITY. In full-face view, cephalic dorsum with small spatulate setae; clypeal dorsum with small subspatulate setae; mandibular dorsum with short appressed fine setae. Surface of scape with appressed stout setae; funiculus densely covered with short fine setae. Dorsolateral margin of head, lateral and anterior clypeal margins, and leading edge of scape with decumbent, narrowly spoon-shaped to shoehorn-shaped setae; those on leading edge of scape apically-directed. Apicoscrobal seta long and flagellate; dorsolateral margin of head without any other laterally-projecting seta. In dorsal view, pronotal humeral seta also long and flagellate. In profile view, dorsal surface of head, dorsum and side of pronotum, dorsum of petiolar node and disc of postpetiole with numerous small decumbent, spatulate to subspatulate setae; mesonotal dorsum with similar but suberect setae; propodeal dorsum only sparsely with appressed to decumbent stout setae; first and second gastral tergites with numerous short erect subspatulate to remiform setae; remaining gastral tergites with a few long flagellate setae against short fine suberect ground pilosity; ventral surface of head with appressed simple setae; gastral sternites with suberect short fine setae. Hairwheel present at mesopleural excavation. Dorsal surfaces of femora with appressed stout to acicular setae, lateral and ventral surfaces with decumbent subspatulate setae; femora without any erect seta; surfaces of tibiae with appressed subspatulate setae; surfaces of middle and hind tibiae and basitarsi with long projecting flagellate setae.

SCULPTURE. Surface of head (including antennal scrobe), antennae, legs and dorsum of petiolar node densely areolate; mandible with sparse weak punctate sculpture and weakly areolate basally, but otherwise mostly smooth. Mesonotal dorsum weakly areolate; pronotal dorsum, propodeal dorsum, side of mesosoma and disc of postpetiole mostly smooth and shining. Basigastral costulae short, around one fourth in length of the first gastral tergite; rest of gaster smooth and shining.

Comments

Strumigenys fellowesi sp. nov. is a member of Subgroup A in the S. godeffroyi -group and shares all its characters ( Bolton 2000), and could be assigned to the smythiesii -complex, which accommodates species that do not belong to the godeffroyi -complex or the mjoebergi -complex. Strumigenys fellowesi is well distinguished from all other species in the species group by the combination of its slightly tapered mandible, the preapical tooth and the apical fork of the mandible in close proximity, a predominantly spatulate to subspatulate pilosity, a smooth pronotal dorsum and a sculptured petiolar node ( Table 7 ).

Aside from Strumigenys fellowesi sp. nov., there are ten other species in the smythiesii -complex that lack a second flagellate seta posterior to the apicoscrobal seta (flagellate or simple) as well as having flagellate pronotal humeral setae ( S. chernovi Dlussky, 1993 , S. datryx Bolton, 2000 , S. ekasura Bolton, 2000 , S. hastur Bolton, 2000 , S. lichiaensis Lin & Wu, 1996 , S. mediocris sp. nov., S. panaulax Bolton, 2000 , S. smythiesii Forel, 1902 , S. tenitecta Bolton, 2000 , S. trada Lin & Wu, 1996 ). Among those species, only S. smythiesii and S. hastur have an unsculptured pronotum, similar to that of S. fellowesi . However, S. hastur has simple standing setae on various dorsal surfaces, while S. smythiesii has erect flagellate setae on the first gastral tergites, both of which are different from spatulate to subspatulate pilosity of S. fellowesi .

Strumigenys fellowesi sp. nov. can be distinguished from S. choii , a Korean species in the S. godeffroyi - group (likely also belonging to the smythiesii -complex) that also has a very similar pilosity, by having the dorsum of the petiolar node sculptured (instead of smooth as in S. choii ), and the apical fork of the mandible with 2– 3 intercalary denticles (instead of absent). Strumigenys fellowesi (HL 0.79–0.80, ML 0.95–0.96) is also a bigger species than S. choii (HL 0.57–0.67, ML 0.71–0.80).

Geographic range

Mainland China (Guangxi).

Figures

Fig. 19. Holotype worker (ANTWEB1011894) of Strumigenys fellowesi sp. nov. A. Full-face view. B. Mandible close-up. C. Profile view. D. Dorsal view.