A mountain of millipedes IX: Species of the family Gomphodesmidae from the Udzungwa Mountains, Tanzania (Diplopoda, Polydesmida).

. A new genus and six new species of the family Gomphodesmidae from the Udzungwa Mts are described, including Pogoro alopias Rosenmejer & Enghoff sp. nov., Pogoro siren Rosenmejer & Enghoff sp. nov., Pogoropsis prolixopes Rosenmejer & Enghoff gen. et sp. nov., Emphysemastix frampt Olsen & Enghoff sp. nov., Agrophogonus hamulus Olsen & Enghoff sp. nov., and Agrophogonus pusillokiellandi Olsen & Enghoff sp. nov. Emphysemastix dracarys Olsen & Enghoff sp. nov. from Iringa city is described. Descriptive notes are given for Pogoro scharffi Hoffman, 2005, and Agrophogonus mwanihana Hoffmann, 2005. General gomphodesmid gonopod morphology is described and illustrated. A key to Udzungwa gomphodesmids is presented, as well as revised keys to all species of Emphysemastix and Agrophogonus . All gomphodesmid species from the Udzungwa Mts are mapped.


Introduction
This is the ninth in a series of articles on the millipede fauna of the Udzungwa Mts. For general information on the Udzungwa Mts, see Enghoff (2014) and Scharff et al. (2015).
as new. Since 2005, almost nothing has been published on Gomphodesmidae: Nzoko Fiemapong et al. (2017) described a new species from Cameroon, and Enghoff et al. (2014) reported on the use of two gomphodesmid species as human food in Burkina Faso.
The family is endemic to sub-Saharan Africa without Madagascar. Within this range, gomphodesmids are found almost everywhere and have a wide range of habitats from rain forests to the savannah biome where they may be extremely abundant (Lewis 1971). They are highly adapted to seasonal semiaridity (Lewis 1971(Lewis , 1974. Their overall appearance (Fig. 1) varies little, but there is a large diversification of the morphology of the gonopods which therefore, as commonplace in millipedes, provide the vast majority of taxonomic characters.
The availability of a recent monograph greatly facilitates taxonomic work on Gomphodesmidae. There are, however, two aspects of Hoffman's magnum opus which limit its utility. Firstly, 17 genera are placed as "Gomphodesminae of uncertain tribal affiliation" and do not appear in the keys to tribes and genera of the subfamily. Secondly,  was very economical with labels on his gonopod drawings. Whereas the drawings themselves are excellent, the lack of labelling frequently makes it difficult to connect the written description to the illustration. For this reason, we here include a labelled general description of a gomphodesmid (more precisely: gomphodesmine) gonopod (Fig. 3). We also include semi-diagrammatic illustrations of two structural elements (paxillus and torus) which are important for the identification of gomphodesmid species (Fig. 4).

Material and methods
All material described in this article is kept in the zoological collections of The Natural History Museum of Denmark (NHMD, formerly ZMUC).  Figure 2 shows the collecting sites of the species. All studied specimens are from Tanzania, Udzungwa (sometimes spelled Uzungwa) Mts, except for the unique specimen of Emphysemastix dracarys sp.nov. from the town of Iringa close to the Udzungwas.
A total of 103 specimens (55 males, 19 females, 29 juveniles) were examined. All samples are kept in 70% ethanol which may have altered their colours. The colours described are based on the current appearance; the colour in life is unknown for all species concerned.
Specimens were examined in alcohol under a stereo microscope. As many specimens were broken into two or more pieces, length measurements could not be precise.
Female sexual characters, which are in general poorly known for Gomphodesmidae, are not considered.
Photographs of gonopods were produced using the high-quality digital imaging system Visionary Digital. A series of photographs of each gonopod was taken from the lowest to the highest point. These photographs were thereafter stacked into one picture, using the focus stacking software Zerene Stacker (http://zerenesystems.com/cms/stacker) for a multifocus image. This process was repeated from three different angles: mesal view, lateral view, and dorsal view. The same method was used for the photographs of the head and telson. The habitus photographs were produced using a Canon Eos 7D Mark II with macro objective. This was necessary due to the size of the entire specimens not fitting in the Visionary Digital system. The photos were roughly edited in Adobe Lightroom, and afterwards in detail in Adobe Photoshop CC; backgrounds were smoothed out to reduce any disruptive visuals and to make the images more similar in overall appearance. Drawings of Pogoro gonopods were produced in Adobe Photoshop European Journal of Taxonomy 675: 1-35 (2020) 4 CC on the basis of the both the photographs and on direct stereomicroscopical observation. Drawings of Emphysemastix and Agrophogonus gonopods were sketched by hand based on direct observation with the stereo microscope, then drawn with an inkpen, and finally scanned as TIFF-files.
It was attempted to make the species descriptions as comparable as possible with those of . Since Hoffman emphasized different characters in different genera, the format of the present descriptions also differs somewhat between genera.

Results
Gomphodesmid gonopod morphology Modified after Hoffman (2005). The description refers to the largest subfamily, Gomphodesminae, to which all species known from the Udzungwa Mts belong. Gonopods in the two other subfamilies, Marptodesmindae and Ovoidesminae, differ in several aspects from those of Gomphodesminae.
The gonopod (Fig. 3) consists of two main parts, the gonocoxa and the telopodite.
The gonocoxa corresponds to the coxa of a normal millipede leg, and shows few differences between genera. Shape, size and setation may vary slightly. In particular, a group of setae, the paracannular setae, is sometimes present on the mesal side of the gonocoxa right in front of the cannula (see below), seen from mesal side. An example of a species lacking paracannular setae is Emphysemastix dracarys sp. nov. (Fig. 14A-B).
The telopodite is connected to the distal end of the gonocoxa and bears little resemblance to the telopodite of the walking legs. Traditionally, authors have attempted to homologize various parts of the telopodite with normal podomeres: prefemur, femur, postfemur, tibia and tarsus. There is hardly any justification for this, cf. that the developmental study by Petit (1976) indicated that the entire polydesmidan telopodite (in casu of a species of Polydesmidae) corresponds to the prefemur of a walking leg. We nevertheless follow  and earlier authors in using the term prefemoral region for the setose basal part of the telopodite. There is no clear demarcation of the distal limit of the prefemoral region. The gonocoxa is connected to the prefemoral region by a tube-like structure called the cannula, supposedly used to pick up sperm from the gonopore found on the third body ring (Koch 2015). Distal to the prefemoral region the telopodite forms a pronounced curve, the sinus. At the distal end of the sinus one finds the nodus, an often voluminous structure furnished with a variety of processes. The nodus may be placed inside the sinus: endonodal, half inside and half outside (to the mesal) side: mesonodal, or, as in the majority of genera, outside the sinus: ectonodal. The usually largest and most complicated nodal process, Process N, usually points to the sinus. Another two processes/spines may be present at approximately the same level, the mesal Process M and the lateral Process L. These two latter can be reduced or completely absent, e.g., in Emphysemastix dracarys sp. nov. (Fig. 14A-F showing absence of Process M). In the genus Agrophogonus the nodus carries several processes which cannot be homologized with N, M and L and are therefore denoted by A, B and C. The part of the telopodite distal to the nodus is called the postnodal telopodite. Various lobes may be present along this part of the telopodite, e.g., the different subapical lobes seen in Pogoro species (Figs 7,9,11), and the subglobose enlargement seen in the genus Emphysemastix (Figs 14, 17). The apical part of the telopodite is called the solenomere.

Key to species of Gomphodesmidae from the Udzungwa Mts
The key also includes Emphysemastix dracarys sp. nov. from Iringa town.
Hoffman (2005) described the sides of the metazona as being "coarsely rugovermiculose"; this character was, however, not observed on any of the type specimens of P. scharffi. Hoffman also stated that there are no paracannular setae in Pogoro scharffi, but some such setae were observed on the holotype and all of the paratypes
As all known species of Pogoro live in the Udzungwa Mts, they can be keyed out using the key to Udzungwa gomphodesmids above.

Remarks
All three species of Pogoro have been collected within a relatively small area in the Udzungwa Scarp FR; the collecting sites are hardly more than 10 km apart (cf. Menegon & Salvidio 2005: fig. 1). Considering that the species are very similar to each other, and that only one male specimen of each is known for two of them, the possibility that they all represent one variable species cannot be excluded. Additional collecting is needed to elucidate this, but for the time being we consider the differences mentioned in the key and description as warranting separate species status.  Figs 2, 5F, 6-7

Diagnosis
Differs from other species of the genus by the shape of the subapical lobes on the postnodal telepodite, and by the shape and curvature of the solenomere. Colour (Fig. 6). Face, collum, metaterga medium brown, legs and antennae lighter, prozona and sterna nearly colourless.
Sternal process on body ring 6. Transverse across sternum with dark brown edge and long setae.
Hypoproct. Almost semicircular, with moderate round median projection, paramedian tubercles above normal size, projecting beyond edge of sclerite.

Distribution
Known only from two very close sites in the Udzungwa Scarp FR (Fig. 2).

Diagnosis
Differs from other species of the genus by the shape of the postnodal telopodite, which resembles a thresher shark's tail, and by the triangular shape of the sternal process on segment 6.

Etymology
The name is a noun in apposition, referring to the thresher shark, Alopias vulpinus (Bonnaterre, 1788), and its tail in particular, the shape of which resembles the postnodal teleopodite in the new species. Other material TANZANIA • 1 ♀; same collecting data as for holotype; NHMD 621671.

Description Male
Size and shape. Body length ca 53 mm. Maximum width 6.9 mm. W/L ratio 13%. Height of body ring eight 4.9 mm. H/W ratio= 72%.

Distribution
Known only from the type locality in the Udzungwa Scarp FR (Fig. 2).

Diagnosis
Differs from other species of the genus by the shape of the postnodal telopodite and by the non-enlarged tubercles on the hypoproct.

Etymology
The name is a Latin noun in apposition, meaning mermaid, and refers to the mermaid tail-like shape of the postnodal telopodite when seen from the mesal side.

Description
Male Size and shape. Body length ca 55 mm. Maximum width 7.8 mm. W/L ratio 13%. Height of body ring eight 6.5 mm. H/W ratio = 83%.
Colour (Fig. 10). Collum and dorsal surface of metaterga dark brown. Face, legs and antennae medium brown. Prozona and ventral surface lighter brown.
Sternal process on body ring 6 (Fig. 5E). Transverse across sternum with dark brown edge and long setae.

Distribution
Known only from the type locality in the Udzungwa Scarp FR (Fig. 2).
Four apical sensory cones on antennae, fossa present on 5 th and 6 th antennomeres. Paranota slightly declivent. Stricture poorly defined, with visible edge only in front of anterior spiracle. Pleurosternal carinae present on body rings 1-17. Anterior legs without ventral tubercles, with sparse setation. Setae on dorsal side of tarsi shorter and stouter than the rest. Subonychial pads on legs 1-6. Sharing most of these characters with Pogoro but differing by: sternal process of segment 6 longer than wide, with triangular tip. Gonopod telopodite relatively long and slender, making a hairpin bend on the middle, so the postnodal telepodite lies close to the prefemoral region. Nodal process L and paracannular setae absent.

Etymology
The genus name refers to the similarity to the genus Pogoro. Gender feminine.

Diagnosis
As for the genus. Differs conspicuously from other Udzungwan gomphodesmids species by the very long and slender gonopod telopodite.

Etymology
The name is a Latin noun in apposition meaning "long leg/foot" and refers to the unusually long gonopods.
Gonopod (Fig. 13). Gonocoxa without paracannular setae. Telopodite mesonodal. Nodus with few small triangular processes. Process M thin, narrow at base, and closely following postnodal telopodite. Process L absent. Postnodal teleopodite relatively long, curved dorsomesad, closely following prefemoral region. Solenomere with triangular lobe, followed by longer and more slender triangular lobe. Apex thin and curved, projecting at right angles before end of solenomere.

Distribution
Known only from the type locality and one further site in the Udzungwa Mts, West Kilombero Scarp, montane forest and open woodland (Fig. 2). The two sites are ca 12 km apart and are situated in different forested areas (cf. Frontier Tanzania 2001: 26, 174).

Remarks
The shape of the sternal process on the 6 th body ring is more similar to that seen in species of the genus Ngurubates Hoffman, 2005, than to that of species of Pogoro. In the key to genera of Gomphodesmini,  actually uses this character to distinguish between Pogoro and Ngurubates. After examining both genus descriptions, however, it became clear that Pogoropsis prolixopes gen. et sp. nov. fits into neither of these genera. Ngurubates species have subonychial pads only on legs 1-5 (Pogoro: 1-6), and ventral tubercles on anterior legs are present (Pogoro: absent). Almost all characteristics of the new species fit Pogoro. The only differences from the Pogoro species description are the absence of paracannular setae, the absence of gonopodal process L and in particular the very elongated, hairpinbent gonopod telopodite.
Gonopod aperture asymmetrically oval, extended back between the 8 th pair of legs, quite large, posterior edge elevated behind the gonocoxae, but not in front of coxae of the 8 th pair of legs. Rim of aperture is thickened, variously emarginate medially. Gonocoxa slanting and shortened as usual, not produced over base of cannula. Prefemoral region without basal fossa on the median side, but deeply impressed on lateral side (where surface is membranous), making prefemur seem almost like carina. Telepodite endonodal. Process M present, varies in both size and shape (exception: E. dracarys sp. nov.). Process L can be quite small, but is larger in some species. Postnodal telopodite curved dorsomesad, with a subglobose, hollow enlargement along the outer curvature. Apex of telopodite with a subterminal process of variable shape and size (e.g., Fig. 15).

Diagnosis
Differs from the other species of the genus by the combination of having a small, not very distinct subtriangular ventral lobe on the gonopod prefemur, missing nodal process M, possessing a welldeveloped process L, and having indentures on the postnodal telepodite on the outer side of the curvature.

Etymology
The name is to be treated as a noun in apposition. The tip of the gonopod looks like the gaping mouth of a dragon when seen from the dorsal side. The word "dracarys" is a command used in the TV series "Game of Thrones" to make dragons breathe fire. Other material TANZANIA • 1 ♀; same collecting data as for holotype; NHMD 621676.

Description Male
Size and shape. A rather slender species. Body length ca 46.5 mm. Maximum width 7 mm. W/L ratio 15 %.
Colour. Dorsum of metazona darker brown than sides, sternum and prozona; paranota light brown. Antennae very dark, legs dark brown.
Body rings. Paranotum of rings 2-4 extended anteriad, on rings 4-19 extended gradually more posteriad. Two transverse carinae on the posterior end of rings 8 and 9, and 4 transverse carinae on rings 10-19. Torus present as clear cones. Stricture relatively deep on dorsal side, with sharp edge in front of anterior spiracles and pleurosternal carinae. Pleurosternal carinae present on rings 2-17, but very small on ring 2. Paxillus triangular, pointed.
Legs. Coxae and prefemora with fewer setae, and basal tubercles smaller than in E. frampt sp. nov. and E. flavosignatus.
Hypoproct. Paramedian tubercles large, extended beyond edge of sclerite, but not beyond end of median projection.

Distribution
Known only from the type locality, Iringa city, some 50 km NW of the Udzungwa Mts (Fig. 2). The altitude of the type locality is ca 1600 m a.s.l. (Carl, 1909) Euryzonus flavosignatus Carl, 1909: 307.

Diagnosis
Differs from the other species of the genus by having a rounded, rather than triangular paxillus. Nodal processes M and L both present.

Etymology
The species is named after Kingseeker Frampt from the Dark Souls video game series, due to the gonopods' resemblance to the creature. The name is to be treated as a noun in apposition.

Description Male
Size and shape. A large member of the genus, rather wide compared to length. Body length ca 55 mm. Maximum width 13.1 mm. W/L ratio ca 24%.
Colour (Fig. 16). Metazona orange-brown, with lighter colour on posterior part and on paranota; legs darker and more intensely/vividly orange. Prozona as metazona but without lighter areas.
Body rings. Paranota set high on sides, dorsum moderately convex. Anterior edge of ring 2-4 straight, anterior edge of rings 5-20 with gradually larger posterior-facing edge. Torus present, but small and indistinct. Stricture poorly defined, but with sharp edge in front of anterior spiracles. Pleurosternal carinae present, knobby, distinct from ring 3, increasing in size towards ring 8-9, afterwards decreasing in size towards posterior end, indistinct on ring 18. Transverse sternal carinae as typical of the genus, but very small on anterior of ring 9. Anterior edge of paxillus rounded, with ridges.
Hypoproct. Paramediean tubercles small, not extended past edge of sclerite. Median projection large and elongated.
Gonopod (Figs 15B, 17). Gonocoxa with some paracannular setae, row of setae continuing on anterior side of distal end of gonocoxa. Prefemoral part with rounded ventral lobe. Telopodite endonodal. Nodal processes M and L similar in size; process L slightly curved mesad; process M slightly longer, distal  end curved mesad. Postnodal telopodite relatively long, curved ventrad almost perpendicular to setose prefemoral region and directed first slightly mesad, then dorsad and expanding into subglobose, hollow enlargement, then curving mesad and forming a half-circle for the rest of its length. Subterminal process narrow and curved ventrad, solenomere curved dorsad, then ventrad.

Distribution
Known only from the type locality in the Nyambanitu Mts, West Kilombero FR (Fig. 2).

Remarks
The gonopods of E. frampt sp. nov. are particularly similar to those of E. flavosignatus (compare Fig. 17 with Hoffman 2005: fig. 206). Processes M and L in E. frampt sp. nov. are, however, longer and more curved, and the nodus is larger, with more divergent sides in E. frampt sp. nov.
Gonopod aperture oval, posterior rim elevated into triangular lobes immediately behind each gonocoxa, cut down to level of sternum medially. Gonopods relatively long and slender, coxae in contact medially, without projection over base of cannula; telepodite set against coxa at a right angle, prefemur slender, nearly straight, gradually narrowed distally, without basal excavation on either side. Nodus entirely endonodal, without trace of median process M, lateral process L present or absent; inner edge of nodus produced into three or four acute projections of varying shape; postnodal telepodite relatively short, curved laterad (longer and curved in a ¾ circle in A. hamulifer sp. nov.), distally either slender and acuminate or laminately flattened, rather abruptly flexed immediately beyond nodus; prostatic groove visible over most of its length in mesal aspect. (modified after Hoffman 2005) 1. Postnodal telepodite short, flattened, laminate (as Fig. 19) .  (Figs 19-20). Nodal process C shorter and less curved (Fig. 21)

Etymology
The name is a Latin noun in apposition, meaning 'carrying a small hook' and refers to the resemblance of the postnodal telepodite to the curvature of a fishing hook.
Colour (Fig. 1). Very pale brown, darker around base of setae. Specimen stored in ethanol since 2000; thus, any pigmentation that may have been present in life is now faded.
Sternal process on body ring 6 (Fig. 5C). Long and slender, but broader towards basis and anterior end. Tip evenly rounded.

Body rings. No transverse sternal carinae.
Telson. Epiproct flattened at posterior end, forming a small vertical plane, with four protruding setae. Hypoproct semicircular to slightly triangular, paramedian tubercles large, extending beyond edge of sclerite. Setae on paraproct protruding from clear basal tubercles.
Gonopod (Fig. 18). Gonopod aperture suboval, extended back between second pair of legs on seventh segment, elevated in front of coxae, eliminated medially. Paracannular setae present. Nodal process L present, process M absent. Processes A and B slender and curved, process C longer than A and B. Processes B and C forcipulate in their curvature and position to each other. Postnodal telepodite very long, slender and acuminate, longer than in other members of the genus, without an abrupt flexure after nodus.

Distribution
Found at two separate locations within the same forest (Ukami) in the West Kilombero FR, Udzungwa Mts.  Agrophogonus kiellandi Hoffman, 2005: 483.

Material examined
None.

Distribution
Known from the type locality: Iringa Region, Iringa District, Udzungwa Mts, Mwanihana FR, 3000-4000 ft a.s.l. (corresponds to 900-1200 m a.s.l.), Sanje River valley, and now also from a very close site at a slightly lower elevation (850 m).

Remarks
The new specimens agree with the description by Hoffman (2005) We here present new illustrations of the gonopod of A. mwanihana, based on one of the newly studied specimens (Fig. 19).

Diagnosis
Differs from the other species of the genus by the combination of small size (width 4.1 mm), a slender postnodal telopodite, and lack of a bifid accessory process laterally on nodus. Virtually similar to A. kiellandi except for size and for having process C of the gonopod telopodite shorter and broader.

Etymology
The specific name is derived from the Latin 'pusillus', meaning 'small', and 'kiellandi', to emphasize the strong similarity with A. kiellandi, except for size.

Description
Size and shape. Body length 20.3 mm (approximate, specimen broken into several pieces). Maximum width 4.1 mm. W/L ratio 20 %. Colour. After 18 years in alcohol without pigmentation (Fig. 20).
Body rings. Sternal process on ring 6 probably damaged, anterior edge very unevenly rounded and jagged (Fig. 21H). Apparently no transverse sternal carinae.
Telson. Epiproct flattened at posterior end, forming a small, vertical flat surface with four protruding setae. Hypoproct semicircular with slightly triangular edge, paramedian tubercles large, extended beyond edge of sclerite. Setae on paraprocts protruding from distinct basal tubercles.
Gonopod (Fig. 21A-G). Gonopod aperture suboval, extending back between second pair of legs on seventh ring, elevated in front of coxae, eliminated medially. Gonocoxa with paracannular setae. Prefemur with deep basal fossa on lateral side. Nodal process L present, process M absent. Processes A and B slender and curved, process C broader and longer than A and B. Processes B and C somewhat forcipulate in their curvature and position to each other. Postnodal telepodite slender and acuminate, slightly flattened, but not laminate as in A. mwanihana and A. harrisi. The right gonopod has a considerably higher number of small spikes and outgrowths than the left, and whereas process L on the left gonopod is slender and lance-shaped (Fig. 21D), on the right gonopod it is laminate and has a secondary tip halfway along its length (Fig. 21E). The angle between the prefemoral region and postnodal telepodite is almost 90° on the left gonopod, but the postnodal telopodite is more slanting posteriad on the right gonopod. The gonopods are almost identical to those of A. kiellandi, but nodal process C is shorter, broader and less curved in A. pusillokiellandi sp. nov. (Fig. 21) than in A. kiellandi   fig. 451).

Distribution
Known only from the type locality, West Kilombero Scarp Forest Reserve, in the Udzungwa Mts, Tanzania.

Remarks
The right-left differences observed on the gonopods of the unique specimen of A. pusillokiellandi sp. nov. emphasize the desirability of having more than a single individual at hand when describing a new species, since with only one specimen it is impossible to estimate the level of intraspecific variation. Basing a new species on a single specimen which is almost identical to a known species (also known only from a single

Discussion
With nine species from the Udzungwa Mts now known, the Gomphodesmidae lag far behind the families so far treated in this series of papers: Odontopygidae with 41 known species (Enghoff 2018a(Enghoff , 2020, and one genus (Eviulisoma) of Paradoxosomatidae with 20 (Enghoff 2018b). Most likely, gomphodesmid diversity is higher in the Usambara Mts, from where eight species have currently been reported (Enghoff et al. 2016), and several additional ones (in coll. NHMD) await description. In contrast, odontopygid and paradoxosomatid diversity is far lower in the Usambaras (HE unpublished). Also in terms of numbers of individuals, gomphodesmids lag behind odontopygids and paradoxosomatids; thus, four of the six new species described here are based on single males. This, on the other hand, suggests that additional new gomphodesmids are likely to be discovered by future collecting efforts.