Lanceobostra chapalaense, Hennemann & Conle, 2024
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publication ID |
https://doi.org/ 10.11646/zootaxa.5444.1.1 |
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publication LSID |
lsid:zoobank.org:pub:5DE4A9DD-99F7-4E23-AD50-58DC491BB75E |
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persistent identifier |
https://treatment.plazi.org/id/3EC8A3A9-FD54-480D-A05B-896DC16AC405 |
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taxon LSID |
lsid:zoobank.org:act:3EC8A3A9-FD54-480D-A05B-896DC16AC405 |
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treatment provided by |
Plazi |
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scientific name |
Lanceobostra chapalaense |
| status |
sp. nov. |
Lanceobostra chapalaense sp. n.
urn:lsid:zoobank.org:act:3EC8A3A9-FD54-480D-A05B-896DC16AC405
( Figs. 37A–B View FIGURE 37 , 38L View FIGURE 38 , 39 View FIGURE 39 GVJ, 40D–F)
HT, ♀: Cojumatlan , Lake Chapala, Mich., Mex. 4–5500 ft.; IX.8–9.1938 (H.R. Roberts) [ ANSP] .
PT, ♂: Cojumatlan , Lake Chapala, Mich., Mex. 4–5500 ft.; IX.8–9.1938 (H.R. Roberts) [ ANSP] .
Diagnosis. This new species is very similar to L. aetolus ( Westwood, 1859) . Females can however be separated by the different armature of the head, somewhat less numerous tubercles of the thorax, posteriorly broader anal segment with a wider posteromedian excavation ( Fig. 39H View FIGURE 39 ) and more closely spaced lobes of the praeopercular organ on abdominal sternum VII ( Fig. 39J View FIGURE 39 ). Males clearly differ by the shape of the anal segment, which has the posterior margin rounded ( Fig. 40E View FIGURE 40 ; medially indented in aetolus ), slenderer vomer, medio-internally more deeply impressed and slightly torquate cerci and lack of a central projection of the poculum ( Fig. 40D View FIGURE 40 ).
Etymology. Named after the type-locality, Lake Chapala in the State of Michoacan.
Description. ♀♀ ( Fig. 37A View FIGURE 37 ): Moderately sized (body length incl. subgenital plate> 151.0 mm; subgenital plate broken in holotype), slender species with a bi-cornute head, tubercular thorax and abdomen and a long, lanceolate subgenital plate. General colouration of the holotype reddish mid brown with a greyish hue along lateral surfaces of thorax, great parts of abdomen and legs. Tubercles of the thorax dull reddish brown, the medioventral keel of the meso- and metasternum contrasting dull orange. Legs faintly annulated with dull ochre and grey. Eyes dull ochre. Antennae drab and most antennomeres with a faint dark ventro-apical marking.
Head: Roundly rectangular, some 1.3x longer than wide, broadest at the eyes with the genae slightly narrowed towards the posterior, vertex flattened, sparsely granulose and with a very shallow, impressed longitudinal coronal line. Behind the eyes with a pair of acute, conical cephalad horns, which have the antero-apical portion slightly deflexed, laterally compressed and carinate. Between the eyes with a pair of long and slender bifid spines. Eyes fairly prominent, circular in outline, strongly convex and their length contained almost 2.5x in that of genae. Antennae slender and roughly reaching half way along abdominal segment II. Scapus dorsoventrally compressed, roundly rectangular in dorsal aspect and about 1.8x longer than wide. Pedicellus round in cross-section and roughly half the length of scapus.
Thorax: Pronotum slightly longer and narrower than head, about 1.8x longer than wide and roundly rectangular in dorsal aspect with the lateral margins straight. Surface sparsely granulose, the anterior margin with a pair of small median tubercles, and a pair of small tubercles near posterior margin. Almost entire length of segment with a fine longitudinal impressed median line. Transverse median sulcus very shallow, short and covering less than half the width of segment. Mesothorax 3.6x longer than head and pronotum combined and with posterior portion very slightly widened. Meso- and metanotum with a fairly distinct longitudinal median carina and all over set with small, conical tubercles. Meso- and metapleurae sparsely granulose and with a longitudinal row of fairly well-developed conical tubercles. Meso- and metasternum with a distinct longitudinal median keel and a fine longitudinal carina along lateral margins, otherwise very sparsely and minutely granulose.
Abdomen: Median segment slightly shorter than metanotum and about 2.3x longer than wide with the lateral margins very gently concave; surface as in meso- and metanotum. Segment II noticeably shorter than median segment. II–V gradually and decidedly increasing in length, VI roughly equal in length to V and VII considerably shorter and roughly equal in length to II; II some 1.6x and V about 2.7x longer than wide. II–VI roughly uniform in width, VII narrowing towards the posterior. Posterolateral portion of tergum VII very slightly deflexed, angular. Terga II–VII tubercular, sterna II–VII with a shallow longitudinal median keel, slightly rugose and sparsely granulose. Praeopercular organ formed by a pair of triangular, laterally compressed, very acute lobe-like teeth at posterior margin of sternum VII ( Figs. 39G, J View FIGURE 39 ). Terga VIII–X noticeably narrower than previous, all slightly tectate longitudinally. VIII about half the length of VII, IX some three-quarters the length of VIII and slightly narrowed medially; both with two weakly defined longitudinal carinae on lateral surfaces. Anal segment about equal in length to VIII, distinctly carinate longitudinally and somewhat narrowed in the posterior portion; posterior margin with a deep, broadly triangular excavation, the outer angles acutely triangular ( Fig. 39H View FIGURE 39 ). Epiproct very small and roundly triangular; hardly visible in dorsal aspect. Cerci small, elongate, almost round in cross-section and narrowed towards a narrow but blunt tip; not reaching to posterior margin of anal segment. Upper gonapophyses somewhat elongated with the apex slightly upcurved, pointed and staying clearly behind posterior margin of anal segment. Subgenital plate with the apex broken in the holotype; distinctly keeled longitudinally and at least projecting over apex of abdomen by combined length of terminal two terga ( Figs. 39G–J View FIGURE 39 ).
Legs: All of moderate length, slender and, with the exception of the mesofemora, entirely unarmed. Profemora somewhat shorter than mesothorax, mesofemora longer than metathorax, metafemora slightly projecting over posterior margin of abdominal segment IV and metatibiae reaching half way along abdominal segment VIII. Two outer ventral carinae of meso- and metafemora with an irregularly shaped, bi- or tridentate lobe-like expansion sub-basally; the posterodorsal carina with one or two small teeth in basal third. Medioventral carina with 2–3 minute spines sub-apically. Probasitarsus a little longer, the meso- and metabasitarsi roughly equal in length to following three tarsomeres combined. All basitarsi with a slight roundly triangular expansion dorso-medially.
♂♂ ( Fig. 37B View FIGURE 37 ): Medium sized (body length 101.0 mm), slender and typical for the genus. General colouration drab with a slight greyish hue on head, pronotum, along lateral surfaces of thorax and great parts of abdomen. Abdominal terga VIII and IX with two weakly defined longitudinal white stripes, the upper stripe continued on anal segment. Longitudinal median keel of meso- and metasternum contrasting dull orange. Cerci greyish straw. Lower portion of genae distinctly white. Legs greyish, the femora becoming paler towards the base and the meso- and metatibiae with a pale sub-basal and sub-apical transverse band. Eyes reddish mid brown with a fine longitudinal dark ocular line. Antennae pale reddish brown.
Head ( Fig. 38L View FIGURE 38 ): Elongate, flattened, some 1.7x longer than wide, broadest at the eyes and gently narrowing towards the posterior; portion between the eyes slightly raised and convex. Eyes prominent, circular in outline, projecting hemispherical and their length contained about 1.7x on that of genae. Antennae very long, moderately slender and reaching to abdominal segment VII. Scapus dorsoventrally compressed, roundly rectangular in dorsal aspect and about 1.3x longer than wide. Pedicellus round in cross-section, very slightly constricted towards the apex and roughly half the length of scapus.
Thorax: Pronotum slightly shorter and narrower than head, rectangular in dorsal aspect, about 1.5x longer than wide and the lateral margins somewhat concave ( Fig. 38L View FIGURE 38 ). Surface very minutely granulose and over entire length with a very fine, longitudinal impressed median line. Transverse median sulcus shallow, straight and expanding hardly more than half the width of segment. Mesothorax 3.7x longer than head and pronotum combined. Mesonotum with a very indistinct longitudinal median carina and sparsely granulose with the granules becoming less decided and less in number towards the posterior. Metanotum very minutely and sparsely granulose. Meso- and metapleurae with a longitudinal row of minute, pale granules. Meso- and metasternum keeled medio-longitudinally and set with a few very minute, scattered granules.
Abdomen: Median segment very slightly shorter than metanotum with the lateral margins very gently concave. Segment II somewhat shorter than median segment, II–V gradually and noticeably increasing in length, VI and VII decreasing in length; II 4x and V 5x longer than wide. II–VI of uniform width, VII very slightly widening towards the posterior and shorter than II. VIII roughly half the length of VII and trapezoidal in dorsal aspect with posterior margin about 1.6x wider than anterior margin. IX a little longer than VII and constricted in posterior half with anterior margin some 1.3x wider than posterior margin; the lateral margins slightly deflexed and rounded. Anal segment shorter than IX slender, parallel-sided, gradually declining in lateral aspect and with a distinct longitudinal median carina, the lateral margins with a shallow concave excavation at bases of cerci, the apical half somewhat constricted and the posterior margin broadly rounded with the outer angles angular ( Fig. 40E View FIGURE 40 ); ventral surfaces of posterolateral angles swollen and multi-dentate. Vomer elongate with a deep medio-longitudinal furrow and the outer margins notably inflated, apex bi-dentate ( Fig. 40F View FIGURE 40 ). Cerci elongate, projecting considerably over posterior margin of anal segment, slightly torquate and shovel-shaped with the interior surface canaliculate longitudinally; widened medially in lateral aspect and slightly constricted basally. Poculum strongly convex, cup-shaped and rectangular in lateral aspect ( Fig. 40D View FIGURE 40 ) with the posterior portion carinate longitudinally and the posterior margin somewhat protruded medially ( Fig. 40F View FIGURE 40 ).
Legs: All long, slender and entirely unarmed except for two minute apical teeth on medioventral carina of meso- and metafemora. Profemora a little longer than head, pro- and mesothorax combined, mesofemora equal to pro- and mesonotum combined and metafemora almost reaching to posterior margin of abdominal segment VI. Basitarsi elongate, slender and longer than remaining tarsomeres combined.
Comments. Since the female sex of this species is currently only known from a unique specimen, some characters in the description above (e. g. armature of the head and legs) must be taken with care. The closely related and similar L. aetolus ( Westwood, 1859) comb. n. shows considerable variability in several morphological aspects (see comments on variation of L. aetolus above) and hence, a similar range of variability must be assumed for L. chapalaense sp. n. Eggs unknown.
Table 15: Measurements of Lanceobostra chapalaense sp. n.
| ANSP |
Academy of Natural Sciences of Philadelphia |
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.