.MUZAFFER ,AHMAD'
BU,LLETIN OF` THE' AMERICAN. MUSEUM OF NATURAL HSORY VOLUME 955: 'ARTICLE 2 NEWV YORK,: 1950
THE PHYLOGENY OF TERMITE GENERA BASED ON IMAGO-WORKER MANDIBLES
THE PHYLOGENY OF TERMITE GENERA BASED ON IMAGO-WORKER MANDIBLES
MUZAFFER AHMAD Department of Zoology University of the Panjab Lahore, Pakistan
THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY AT THE UNIVERSITY OF CHICAGO
BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY VOLUME 95: ARTICLE 2 NEW YORK : 1950 BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY Volume 95, article 2, pages 37-86, text figures 1-17 Issued May 19, 1950
Price: $.60 a copy CONTENTS
. INTRODUCTION...... 43
...... Material and Technique . 43
. Terminology ...... 46
. PHYLOGENETIC STUDY...... 49
. Mastotermitidae ...... 49
Kalotermitidae ...... 49
. Hodotermitidae ...... 51
Rhinotermitidae ...... 53
Termitidae ...... 56
Macrotermitinae ...... 57
Nasutitermitinae ...... 59
Amitermitinae ...... 64
Termitinae ...... 68
Serritermitinae ...... 75
DIscusSION...... 76
SUMMARY...... s80
APPENDIX...... * 81
BIBLIOGRAPHY...... * 85
41
INTRODUCTION THE STUDY OF PHYLOGENY aims at the recog- termites based primarily upon the imago- nition of the relationships of organisms within worker mandibles, though not entirely ex- a group based upon their descent. There are. cluding other characters. In some cases the various lines of approach to the understand- imago-worker mandibles alone have proved ing of such relationships. Using any of the inadequate for the establishment of exact phases of biology, such as comparative mor- relationships. The phylogenetic series in such phology, physiology, embryology, ecology, groups has been built upon information con- genetics, zoogeography, or paleontology, one cerning other aspects of their biology. In this can arrive at phylogenetic interpretations. connection zoogeography has been of par- In a study like the one presented in this ticular help. paper, in which a large number of genera are The imago-worker mandibles of generi- involved and access to all species in the living types, when available, have been studied condition is difficult, comparative morpho- with the assumption that there is no funda- logy is perhaps the best tool of attack. Sound mental variation within the genus. In some studies of comparative morphology can be of instances, a comparison of the imago-worker great value in elucidating some of the im- mandibles of the generitype with those of the portant principles of biology. This paper at- other species of the same genus was made to tempts to lay a foundation for such inter- determine the degree of variation. Except in pretations. a few cases, where there is some indication of The mandibles of the imago and the worker variability, this character was found to be castes in termites provide a very useful fairly constant. Genera showing large varia- morphological character for the study of tion need revision and reassignment of the phylogeny. This character is conservative species, but such a study is beyond the scope and is almost identical in the two castes. of this paper. In the future, with better Holmgren (1911, 1912) was the first investi- knowledge of these complexes, the phylo- gator to take cognizance of this character in genetic scheme presented here (figs. 1-4) may building his classification. Many years later, still be improved. Hare (1937), while establishing the phy- I am greatly indebted to Dr. Alfred E. logeny of termites on the basis of soldier Emerson for suggesting the problem and mandible development, also made frequent taking keen interest in the progress of the use of the imago-worker mandibles in the work. Dr. James A. G. Rehn of the Academy support of her conclusions. The present work of Natural Sciences of Philadelphia has been is the first thorough study of the relation- kind in lending me representatives of some ships of virtually all the living genera of genera of roaches.
MATERIAL AND TECHNIQUE Except for three genera of roaches lent me incorporated into this study on the basis of by the Academy of Natural Sciences of the descriptions alone. Philadelphia, the entire study is based upon The mandibles were dissected in 80 per cent the termites in the collection of the American alcohol, and drawings made with the help of Museum of Natural History, now in the a camera lucida. Usually the mandibles of custody of Dr. Emerson. When the generi- the worker caste were drawn because they type was not available or was poorly repre- were numerically better represented in the sented in the collection, other species in the collection than the imago caste. Several genus were substituted. In the majority of workers, depending upon the availability of cases the species were metatypes (compared the material, were dissected and their man- with type specimens). A total of 140 species dibles compared in order to avoid any mis- (see Appendix) representing three genera of take resulting from the mixture of species in roaches and 137 genera and subgenera of the field or in the vial. Whenever the imagoes termites was studied. Two genera of termites, were available their mandibles were com- viz., Euscaiotermes and Rostrotermes, which pared with those of the worker. were not available in the collection have been 43 44 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95
DOLICHORHINOTERMES RHINOTERMES TERMI TOGETON SCHEDORHINOTERMES STYLOTERMES PARRHINOTERMES RETICULITERMES
PRORHINOTERMES HETEROTERMES COPTOTERMES PSAMMOTERMES
ANACANTHOTERMES
MICROHODOTERWMES POROTERMES HODOTERMES RHINOTERMITIDAE ZOOTERMOPSIS STOLOTERMES HODOTERMOPSIS
ARCHOTERMOPSIS
HODOTERMITIDAE
CRYPTOTERMES ICALCARITERMES
EUCRYPTOTERMES
RUGI TERMES., n GLYPTOTERMES
NEOTERMES
PARANEOTERMES PROCRYPTOTERMES L%- KALOTERMES
KALOTERMITIDAE
FIG. 1. Hypothetical phylogenetic tree of the families Kalotermitidae, Hodotermitidae, and Rhinotermitidae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 45 GNATHAMITERMES DREPANOTERMES AMITERMES
EREMOTERMES SYNHAMI TERMES PSEUDOMICROTERMES LABRI TERMES CYLINDROTERMES CEPHALOTERMES PROHAMI TERMES AHAMITERMES GLOB! TERMES HOPLOTERMES AMPHIDOTERMES EUHAMI TERME MICROCEROTERMES ANOPLOTERMES SPECULI TERMES
EURYTERMES I AMITERMITINAE
PROTOHAMITERMES I
MICROTERMES
ANCISTROTERMES EUSCA IOTERMES HYPOTERMES MACROTERMES ODONTOTERMES SYNACANTHOTERMES SPHAEROTERMES PSEUDACANTHOTERMES PROTERMES ACANTHOTERMES ALLODONTERMES
MACROTERMITINAE
FIG. 2. Hypothetical phylogenetic tree of the subfamilies Macrotermitinae and Amitermitinae. 46 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 ,EUTERMELLUS
,TRINERVITERMES OCCASI TERMES OBTUSITERMES CONVEXITERMES MIMEUTERMES CEYLONI TERMES TUMULI TERMES $1SUBULI TERMES TENUIROSTRITERME ( PARVI TERMES
VELOCITERMES (HOSPITAL ITERMES DIVERSI TERMES LACESSITITERMES ANGULARITERMES ROTUNDI TERMES CCONSTRICTOTERMES BULBITERMES CURVITERMES NASUTITERMES GGRALLATOTERMES ARMITERMES K COARCTOTERMES HAVILANDITERMES- IONG IPEDI TERMES
HIRTI TERMES LABIOTERMES RHYNCHOTERMES (j
TRIACITLERME NASUTITERMITINAE -SYNTERMES FIG. 3. Hypothetical phylogenetic tree of the subfamily Nasutitermitinae. TERMINOLOGY Snodgrass (1935) refers to the distal part Emerson's terminology has been adopted. of the mesal surface of the mandible with The two sides of the marginals will be re- teeth as the incisor lobe and the proximal ferred to as the anterior and posterior edges. part as the molar lobe. Emerson (1933) des- The entire edge is single from the apical to ignates the first tooth of the incisor lobe of the last marginal, whereas the molar area is Snodgrass as the apical tooth and the rest as hollowed out into a cavity into which fits the the marginal teeth which in primitive mandi- corresponding part of the mandible of the op- bles like those of Cryptocercus (fig. 5) are posite side. The under side of the molar plate further distinguished as the first, second, and is wedge shaped which, when seeil from third marginal teeth. He refers to the molar above, looks like a tooth in some mandibles. surface posterior to the marginals as the The latter should not be mistaken for any of "molar plate." Because of the ease in com- the marginals. paring the individual homologous teeth 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 47 PROCAPRITERKES CAPRITERMES PROTOCAPRITERMES CORNICAPRI I MIROCAPRI TERME QUASI TERMES .FEPITITERMES 'CAVITERMES LCULITERMES | IITERMES j ANGUL I TERMES i j TERMES TERMITINAE FIG. 4. Hypotbetical phylogenetic tree of the subfamily Termitinae. 48 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 CRYPTOT CALCARITERMES EUCRYPTOTERMES YPALOTERMES GLYPTOnERMES MASTOTERMES. RUGITERMES PANESTHI NEOTERMES es~ ,NCAUOELLI_A G~~~~ PARANEOTERMES FIG. 5. Imago-worker mandibles of the families Blattidae, Mastotermitidae, and Kalotermitidae. PHYLOGENETIC STUDY MASTOTERMITIDAE THE FAMILY MASTOTERMITIDAE is repre- tionship is borne out by the findings of Cleve- sented by a single living species, Mastotermes land et al. (1931, 1934) who report a striking darwiniensis Froggatt, from Australia. In similarity of the cellulose-digesting flagellates general it is considered to be the most prim- of Cryptocercus to those of termites. Dis- itive of all the modern termites, although cussing the bearing of this relationship on the in a few respects it shows specialization over evolution of termites, the authors in their some of the otherwise higher termites be- 1934 paper remark, "the evidence is over- longing to the Kalotermitidae and the Hodo- whelming that this roach is either the an- termitidae. cestor of termites or is closely related to the Mastotermes shares with roaches a large ancestor which is extinct." While agreeing number of characters, of which the most re- fully with the second part of their remark, I markable is the presence of an anal lobe in take exception to the view that Cryptocercus the hind wing. Another important blattoid could be the ancestor of termites. Some feature in the hind wing is the absence of a earlier blattoid stock which had wings and basal suture which is present in all other had already acquired the symbiotic Protozoa termites. Crampton (1923) reports many may be considered as the common ancestor other structural resemblances between Mas- of Cryptocercus and termites. totermes and roaches, such as the origin of the In the imago-worker mandibles, Masto- pygidium from the tenth abdominal segment, termes (fig. 5) shows a much higher specializa- the well-developed paraprocts, and the partial tion than Cryptocercus. The marginals of the fusion of the styli-bearing organs. These left mandible are reduced from three in homologies have been studied further and Cryptocercus to two in Mastotermes, a condi- confirmed by Browman (1935). The egg tion more specialized than in some of the masses of Mastotermes are similar to the hodotermitids. The reduction was probably oothecae of roaches. There is therefore little brought about either by complete regression doubt about the blattoid ancestry of Masto- of one tooth or by the fusion of the first termes. marginal with the second or of the second None of the modern roaches can be con- with the third. Judging from the condition in ,sidered to be the ancestor of termites. All the Termopsinae where a gradual reduction alate modern roaches have horny forewings. of the fully developed second marginal of The membranous wings of termites are more Archotermopsis (fig. 6) to a rudimentary con- primitive. Moreover, Tillyard (1931) doubts dition in Zootermopsis (fig. 6) has occurred, it the exact homology of the anal lobe of the is quite likely that the second marginal in the hind wing of Mastotermes. He thinks that it Mastotermitidae might have undergone is not complete as it includes only the second further regression. In the biology the Masto- anal vein and its branches and that the line termitidae is more advanced than the next of folding does not correspond with that in family, the Kalotermitidae. Probably after the blattids. Among the modern blattids, the separation from the ancestral stock it has Cryptocercus punctulatus Scudder, the sub- continued specialization in a direction not social, wingless, wood-feeding roach, bears exactly in line with other termites, although closest relationship to termites. This rela- retaining some primitive characters. KALOTERMITIDAE There is strong evidence that the Kaloter- arolium in both the families further strength- mitidae arose from Mastotermes-like an- ens their relationship. Kirby's study (1945) cestors. The imago-worker mandibles (fig. 5) on the distribution of the termite flagellates are essentially the same as in the Mastoter- belonging to the genus Metadevescovina pro- mitidae. The presence of the ocelli and the vides additional evidence in support of this 49 50 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 affinity. These flagellates are known only indication of some variability in the imago- from the Kalotermitidae and the Mastoter- worker mandibles of this genus. It needs re- mitidae, and interestingly enough more than vision and reassignment of its species. half of the species, 10 out of 15, reported Probably the Procryptotermes-Cryptotermes from the Kalotermitidae are confined to branch arose from the Kalotermes stem. Kalotermes, the most primitive genus of the Cryptotermes is more advanced than Pro- family. None of the higher kalotermitids, cryptotermes, as indicated by its more highly such as Cryptotermes, Eucryptotermes, and developed phragmotic head and the less Calcaritermes, are known to harbor these elongated anterior edge of the second mar- flagellates. ginal of the left mandible. Neotermes is In the light of this evidence there is little closely related to Kalotermes. The wing vena- doubt that the Kalotermitidae arose from tion of Neotermes is a little more specialized mastotermitid-like ancestors. However, their than that of Kalotermes. The median has direct origin from Mastotermes seems rather shifted nearer to the radial sector, as com- improbable. The large size of the colony and pared to the position midway between the the fairly highly evolved nesting behavior of cubitus and the radial sector in Kalotermes. Mastotermes indicate its higher specialization This difference is, however, not absolute. The compared to the kalotermitids. The latter wing venation of K. jouteli is similar to that have comparatively small colonies; their nest of Neotermes. architecture is primitive, consisting of exca- Paraneotermes shares many characters with vations in wood and the construction of both Kalotermes and Neotermes. I am rather simple partitions. Perhaps the Kalotermitidae doubtful of the generic validity of Paraneo- arose as an offshoot from the early termite termes. With a more detailed study it may stock before evolution had gone far in the prove to be another intermediate form like direction of Mastotermes. K. jouteli. At present I am treating it as a The presence of a large number of transi- genus as originally erected by Light (1937) tory forms in the Kalotermitidae creates a and assigning it to a position intermediate great difficulty in the sharp differentiation of between Kalotermes and Neotermes. the genera. The imago-worker mandibles Rugitermes shows a further advance over have not proved of much help in under- Neotermes through the coalescence of the standing the phylogenetic relationships with- median with the radial sector in the outer in the family except for indicating two di- half. verging lines of evolution. The first line, Glyptotermes shows some distinct advance represented by Procryptotermes and Crypto- over Neotermes. The wing venation is more termes, is characterized by a comparatively consolidated in that the median vein is en- marked elongation of the anterior edge of the tire, unlike that in Neotermes in which the second marginal and shortening of the pos- median vein is joined to the radial sector by terior edge of the first marginal of the left four to six cross veins. The soldier shows the mandible (fig. 5). The posterior edge of the beginning of the development of the phrag- second marginal of the right mandible is also motic head. conspicuously elongated. The second line, In the remaining two genera, viz., Eucryp- ending in Calcaritermes, does not show much totermes and Calcaritermes, the soldier has a marked elongation of the edges of the mar- well-developed phragmotic head. While it is ginals. The terminal ends of these two lines probable that Calcaritermes arose from Glyp- of evolution, represented by Cryptotermes and totermes, the origin of Eucryptotermes seems Calcaritermes, show convergence in the evo- to have taken place earlier. This conclusion lution of the phragmotic head of the soldier is based upon the fact that the wing venation caste. of Eucryptotermes is more primitive than that Kalotermes is the most primitive genus of of Glypotermes. In the development of the the Kalotermitidae, as evidenced by its wing phragmotic head, Eucryptotermes is even venation (the median being midway between more advanced than Calcaritermes and repre- the cubitus and the radial sector) and the sents a convergent evolution of this adapta- elongate shape of its soldier head. There is an tion. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 51 POROTERMES ANACANTHOTERMES ZOOTERMOPSIS Ml CROHODOTERMES HODOTERMES HODOTERMOPSIS STOLOTERMES ARCHOTERMOPSIS FIG. 6. Imago-worker mandibles of the family Hodotermitidae. HODOTERMITIDAE The Hodotermitidae seem to be an off- imago-worker mandibles is the small sub- shoot from primitive Isoptera possessing the sidiary tooth at the base of the anterior edge characters common to the Mastotermitidae of the first marginal of the right mandible. and the Hodotermitidae. While still main- This small tooth is found throughout the taining a very close similarity to the blat- Rhinotermitidae and in some of the primitive tids in the imago-worker mandibles (fig. 6) fungus-growing genera belonging to the sub- this group has evolved a higher social or- family Macrotermitinae of the Termitidae. ganization. Some of the hodotermitids, so far So far the studies of Cryptocercus and related as is known, have an adult worker caste genera such as Ancaudellia and Panesthia which is absent in the Kalotermitidae. One (fig. 5) reveal the absence of the subsidiary new character of phylogenetic importance tooth in the Blattidae. which appears here for the first time in the Among the subfamilies of the Hodoter- 52 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 mitidae, the Termopsinae are the most primi- structures of some female termites that tive. Their imago-worker mandibles come Porotermes is "a possible branching off from closest to the blattoid type. Of the three the Kalotermes stem early in its history." genera included in this subfamily, Archoter- This is not possible because the mandibles of mopsis is least specialized. In the possession the Hodotermitidae cannot be derived from of six-jointed to eight-jointed styli and the those of any kalotermitid. Though showing large reniform eyes, it is even more primitive resemblance to Zootermopsis in its imago- than Mastotermes (Imms, 1919). A linear ar- worker mandibles, Porotermes cannot be rangement of the genera of the Termopsinae placed in the same subfamily because of is possible (Emerson, 1933). There is a the presence of several specialized char- gradual reduction of the second marginal of acters. Emerson (1942) considers Porotermes the left imago-worker mandible. This tooth is to be at the same evolutionary level as Stolo- most reduced in Zootermopsis. Hodotermopsis termes. presents an intermediate condition between The Hodotermitinae are the most highly Archotermopsis and Zootermopsis in the de- evolved among the subfamilies of the Hodo- velopment of the second marginal. Correlated termitidae. The imago-worker mandibles with the reduction of this character is the show a distinct advance over those of the corresponding widening of the angle between Archotermopsis-Zootermopsis type. The sec- the second and the third marginals. This re- ond marginal of the left mandible is almost lationship is further borne out by other mor- completely reduced and in many cases it is phological characters, such as reduction in hardly visible. Other advances that the hodo- the size of cerci and styli from Archotermopsis termitids exhibit are the presence of a to Zootermopsis. worker-like caste and a high degree of social The Stolotermitinae are represented by a organization. They are commonly called single genus, Stolotermes. Their relationship "harvester termites." The worker-like in- has been discussed at some length by Emer- dividuals pile up grass bits in the nests which son (1942). Their mandibles are homologous consist of large globular excavations made in to those of the Termopsinae and come closest the soil. These cavities are filled with papery to those of Archotermopsis. Their specialized shelvings and are supported by cylindrical characters as compared to Archotermopsis columns. This is a great architectural ad- are: the four-jointed tarsi, the four- to five- vance over the other hodotermitids which jointed cerci, the shorter styli, and the ab- make simple partitions from their pellets of sence of the arolium. On the basis of these and excrement in rotten logs in shady, moist other characters Emerson (loc. cit.) thinks localities (Imms, 1919). In respect to the that "we should place Stolotermes as a genus imago-worker mandibles, all three genera of of the Hodotermitidae somewhat more spe- the Hodotermitinae are essentially similar cialized than Archotermopsis and best con- and present the same evolutionary stage. sidered as an offshoot from the Hodotermitid With the help of other characters it is possible base and not ancestral to any other living to trace their phylogenetic relationships. termites but possessing many characteristics Hodotermes and Microhodotermes have lateral that are ancestral in type to other termite tibial spines which are lost in Anacantho- groups, notably the Rhinotermitidae." termes. The presence of the lateral tibial The Porotermitinae are likewise repre- spines in the first two genera indicates their sented by a single genus, Porotermes. Their primitive condition compared with Ana- imago-worker mandibles are comparable to canthotermes. Microhodotermes has more spe- those of the Termopsinae and are very close cialized wing venation than Hodotermes, as to those of Zootermopsis. Browman (1935) indicated by the loss of the branches from the concludes from his studies of the abdominal radial to the subcosta. 195019. AHMAD: PHYLOGENY OF TERMITE GENERA 53 RHINOTERM ITIDAE The Rhinotermitidae are more primitive termitidae cannot be derived from the kalo- than the Kalotermitidae in the character of termitid stock. the imago-worker mandibles (fig. 7) as evi- The Coptotermitinae come next to the denced by the possession of the full comple- Psammotermitinae in the evolutionary se- ment of three marginals and the subsidiary quence. The second marginal of the left tooth, a pattern seen in roaches, Archoter- mandible of Coptotermes, the only repre- mopsis, and Stolotermes. It is therefore prob- sentative of this subfamily, is less stout and able that the Rhinotermitidae arose from is shorter than in Psammotermes, and there is termites possessing mandibles of the Archo- also a similar reduction of the first marginal termopsis-Stolotermes type and not from the of the right mandible. The soldier mandibles Kalotermitidae as suggested by Holmgren show a still greater departure from the (1911) and Hare (1937). The exact ancestor Psammotermes type. The teeth are almost can, however, be neither Archotermopsis nor lost save for the slight sinuation or serration Stolotermes, but is some common ancestor of at the base. The frontal gland has undergone both having ocelli. Primitive hodotermitids, considerable development. This creates a big after having lost the ocelli, could not give rise gap between the Psammotermitinae and the to forms with ocelli. Coptotermitinae. The latter have closer rela- The study of the imago-worker mandibles tionships with the next subfamily, the Hetero- reveals the presence of two distinct cate- termitinae, than with the Psammotermitinae. gories in the Rhinotermitidae. One has the The Heterotermitinae, though close to the second marginal of the left mandible longer Coptetormitinae, possess several distinct than the first and the other has this tooth higher revolutionary features, such as the re- shorter (except in Reticulitermes in which it duction of antennal articles, pronotum, an- is as long as the first). This grouping of the terior wing scales, and the 3:2:2 tibial spurs rhinotermitid genera, except for the inclusion (3:3:3 in the Coptotermitinae). No soldier in of Prorhinotermes in the first category and of the Heterotermitinae is known to possess eye Stylotermes in the second, is in line with the spots. There is one record of the presence of existing knowledge of their phylogenetic re- rudimentary eyes in the soldier caste in the lationships. The first category (excluding Coptotermitinae. Hill (1942) reports that the Prorhinotermes and comprising four sub- eye spots are visible in Coptotermes grandiceps families, the Psammotermitinae, the Copto- Snyder. Before giving weight to this char- termitinae, the Heterotermitinae, and the acter it should be verified by anatomical Termitogetoninae) is more primitive than study. A broad clypeus in the Heterotermi- the second category (excluding Stylotermes tinae is another specialized charcter. and comprising the Rhinotermitinae). The Heterotermes and Reticulitermes are the two imago-worker mandibles, though conforming genera included in the Heterotermitinae. to the type characteristic of this family as a Reticulitermes, while still sharing with Hetero- whole, have been of some help in indicating termes such characters as the parallel-sided two main lines of evolution in the Rhino- soldier head and the flat pronotum of the termitidae. worker which justify its inclusion in the The Psammotermitinae, represented by a Heterotermitinae, has undergone great spe- single genus, Psammotermes, are the lowest cialization in many other characters. Its among the Rhinotermitidae in the evolution- ecology and protozoan relationships, to- ary scale. The soldier mandibles are primi- gether with some morphological characters tive, as evidenced by the presence of a large (small anterior wing scale, second marginal number of teeth. They bear some resem- of the left mandible as long as the first), blance, though not close, to the soldier mandi- separate it widely from Heterotermes. bles of the Termopsinae. Holmgren (1911) The phylogenetic position of the Styloter- shows Psammotermes arising from the Kalo- mitinae is rather problematic. The imago- termitidae stem in his phylogenetic tree, but, worker characters present a considerable ad- on the grounds discussed earlier, the Rhino- vance over those of the three subfamilies dis- 54 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 TERMITOGETON DOLICHORHINO-TERMES STYLOTERMES RHINOTERMES RETICULI TERMES SCHEDORHINOTERMES HETEROTERMES PAARHINOTEPMCS PRORHINOTERMES PSAMMOTERMES FIG. 7. Imago-worker mandibles of the family Rhinotermitidae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 55 MICROURMES ALLODONTERMES ANCISTROTECRMES MACOTERES HYPOTERMES SYNACANTHOTERMES ODONTOTERMES PSEUDACANTHOTERMES SPHAEROTERMES AC.ANTHOTERMES FIG. 8. Imago-worker mandibles of the subfamily Macrotermitinae. 56 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. .95 cussed above, whereas the soldier caste pos- Termitogeton type. Holmgren (1911) includes sesses several primitive characters which bear Prorhsinotermes (= Arrhinotermes) under the superficial resemblance to those of some kalo- Coptotermitinae, but such characters as the termitids. It was on the basis of this super- large clypeus of the imago, the reticulation of ficial relationship that Holmgren and Holm- the wing membrane, the shape of the soldier gren (1917) suggested a Kalotermes ancestry head and its elongate labrum and the saddle- of Stylotermes. Snyder (1931) also agrees with shaped pronotum of the worker leave no their view. They remark, "Stylotermes is of doubt of its close affinity to the other genera particular interest since it exhibits characters of the Rhinotermitinae. Prorhinotermes repre- which are connecting links between the sents the basic stock from which other genera lower termites in the family Kalotermitidae of the Rhinotermitinae have arisen. Some of and those in the intermediate family Rhino- the diagnostic characters of the subfamily, termidae." Being a rhinotermitid, Stylotermes for example the swollen clypeus and the cannot be derived from the Kalotermitidae. saddle-shaped pronotum of the worker, are I place Stylotermes next to Heterotermes be- still not so pronounced in Prorhinotermes as cause it has the same type of wing venation in the higher genera. and tibial spur arrangement but is more Parrhinotermes shows a distinct advance specialized in the imago-worker mandibles over Prorhinotermes. Its second marginal is which are of the Rhinotermitinae type. distinctly smaller than the first, and the The Termitogentoninae are the highest soldier is devoid of faceted eyes which are so evolved subfamily in the series in which the distinctly seen in Prorhinotermes. The reduc- second marginal is longer than the first. Their tion of the antennal articles and the saddle- specialized characters, not shared with any shaped pronotum of the worker are some other of the subfamilies of the Rhinotermiti- other specialized characters of Parrhino- dae hitherto considered, are the reduction of termes. the wing venation (the radius and the The remaining three genera, Schedorhino- median either absent or faintly present), the termes, Rhinotermes, and Dolichorhinotermes, 2:2:2 tibial spurs, and the anteriorly nar- have dimorphic soldiers. Of these, Schedo- rowed soldier head. rhinotermes is more primitive. The minor The Rhinotermitidae have well-defined soldiers have mandibles with teeth. The diagnostic .characters such as the large fore- clypeus of the imago is swollen but does not wing scale, the swollen clypeus of the imago, yet appear to be elongate. The mandibles of the second marginal shorter than the first the minor soldier of Rhinotermes are very (except in Prorhinotermes), the anteriorly delicate and devoid of any tooth. The labrum narrowed soldier head, and the saddle-shaped is much more elongate, as is the clypeus of pronotum of the worker. the imago. In Dolichorhinotermes the major Prorhinotermes is the most primitive genus soldier has a more elongated labrum than of the Rhinotermitinae. Its imago-worker either Schedorhinotermes or Rhinotermes. mandibles are still of the Psammotermes- TERM ITIDAE The Termitidae are the largest and most presence of the subsidiary tooth in some of highly evolved family of termites, comprising the primitive genera of the fungus-growing five subfamilies-the Macrotermitinae, the termites of the subfamily Macrotermitinae Nasutitermitinae, the Amitermitinae, the and in one genus, Protohamitermes, of the Termitinae, and the Serritermitinae. These Amitermitinae supports the postulation of subfamilies cannot be arranged in any linear such an origin of the Termitidae. Proto- order. After emerging from the ancestral hamitermes still has all the three marginals of stock each has followed a different course of the left mandible (fig. 12) which seem to be evolution. Regarding the origin of the family homologous with those of the Rhinotermiti- Termitidae, it is very probable that it arose dae. from some rhinotermitid-like ancestor. The 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 57 MACROTERMITINAE number of specimens of Protermes reveals the The subfamily Macrotermitinae, while presence of the subsidiary tooth which ap- possessing some primitive morphological fea- parently seems to have been missed by Hare. tures compared to other subfamilies of the I therefore assign Protermes to a lower posi- Termitidae, exhibits specialization in its tion in the phylogenetic tree of the Macro- biology. All its genera and species have termitinae (fig. 2). In this respect I am more in evolved an intricate instinct of fungus grow- agreement with Holmgren (1912) than with ing. The imago-worker mandibles (fig. 8) Hare. Holmgren, however, puts Protermes at have essentially the same pattern throughout the base of the tree, which does not seem to the subfamily except for the presence of the be justifiable. Though it shares the subsidiary subsidiary tooth in some of its primitive tooth with Acanthotermes it has many char- genera. The second marginal of the left acters more specialized, such as fewer articles mandible is considerably reduced and is rep- in the antennae, the thorax of the soldier resented only by the broadly rounded lower without lateral spines, and the monomorphic end of the posterior edge of the first marginal. soldiers. Allodontermes is very closely related In this character and in the reduction of the to Protermes, though somewhat more prim- forewing scale, the Macrotermitinae exhibit itive as indicated by the presence of the a higher specialization compared to the hyaline tip of the soldier labrum and the Rhinotermitidae. larger number of the antennal articles. The Acanthotermes is the most primitive genus soldier mandibles also are more primitive of the subfamily. Its primitive characters not than those of Protermes. shared with other genera are the prominent The genus Sphaerotermes has been placed lateral spines of the mesothorax and meta- at a lower level than Macrotermes by both thorax and the trimorphic soldiers. Pseuda- Holmgren and Hare, but I, again on the basis canthotermes has a poorly developed subsidi- of the relative degree of the development of ary tooth, and the thorax is devoid of the the subsidiary tooth, assign it to a position lateral spines. The soldiers are dimorphic. next to Macrotermes. Synacanthotermes is closely related to Pseuda- The remaining three genera, viz., Odonto- canthotermes as it has, in common with the termes, Ancistrotermes, and Microtermes, have latter, the subsidiary tooth and the trilobed essentially the same type of imago-worker hyaline tip of the soldier labrum, but in its mandibles. The subsidiary tooth is lost com- monomorphic soldier and in the absence of pletely. The stoutly built soldier mandible of the prothoracic processes it is more advanced. Odontotermes, with its distinct tooth, is a Hare (1937) considers Macrotermes to be primitive character compared to the condi- the most specialized genus of the Macroter- tion in Ancistrotermes and Microtermes. If the mitinae on the basis of the "nearly smooth depth of the cut between the third marginal condition" of the third marginal. The depth and the molar plate of the left mandible of the cut between the third marginal and the studied by Hare is used, it is possible to ar- molar plate is considered by the author as a range the subgenera of Odontotermes in a phylogenetic character. Giving more weight linear fashion. They fall in the sequence of to the fact that Macrotermes has a distinct sub- Odontotermes, Hypotermes, and Euscaiotermes. sidiary tooth in the imago, I am inclined to The drawings of the worker mandibles of think that this genus arose from a much Euscaiotermes as given by Silvestri (1923) earlier stock than Hare postulates. The stock show the third marginal to be the least that gave rise to Acanthotermes was probably deeply cut. ancestral to Macrotermes also. The somewhat Ancistrotermes and Microtermes have laterally produced margins of the meso- soldier mandibles more delicate than Odonto- thorax and metathorax and the trilobed termes, and in some species of Mictrotermes the hyaline tip of the soldier labrum in some tooth of the soldier mandible is weakly de- species of Macrotermes further suggest its re- veloped. The fungus gardens of Microtermes lationship to Acanthotermes. are simple, possibly because they are reduced My placement of Protermes also is different in size and the convolutions of the surface are from that of Hare. An examination of a large not necessary. This would be an evolutionary 58 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 TITEFMES ITERMES XRALLATOTERMES RHYNCHOTERMES COARCTOTERMES TRIACITERMES CORNITERMES LONGIPEPEDITERMES NASUTITERMES PROCORNITERMES SYNTERMES HAVILANDITERbMES FIG. 9. Imago-worker mandibles of the subfamily Nasutitermitinae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 59 reduction. Microtermes has monomorphic both genera is not particularly wide in the soldiers, with the head narrowed anteriorly, middle in contrast to the wide postmentum and should be considered to be more ad- in the higher Macrotermitinae, and both vanced than Ancistrotermes which has dimor- Syntermes and Acanthotermes possess three phic soldiers. spines near the tip of the tibiae of the foreleg and two spines on the tibiae of the other legs NASUTITERM ITINAE (3:2:2)." After discussing the specialized There is little doubt that the Nasutiter- characters of Syntermes he comes to the con- mitinae and the Macrotermitinae arose from clusion that "Inasmuch as each of these prim- a common stock. The subfamily Nasutiter- itive genera of the Macrotermitinae and mitinae presents some of the best cases for Nasutitermitinae has generalized characters the study of the phylogenetic sequence be- not found in the other subfamily, we must cause of the existence of many intermediate suppose that neither developed directly from forms. A gradual evolution of the nasute the other, but both are descended from an ex- soldier from the typically mandibulate type tinct group possessing the primitive char- can be traced. Correlated with the evolution acters of both of these subfamilies." of the nasus and the frontal gland is the ac- The next higher genus is Procornitermes companying degeneration of the soldier (fig. 9). Some of the characters of this genus mandibles. The phylogenetic positions of are so much more specialized than in Syn- many of the nasute termites are not wholly termes that a big gap is left between the two clear from the available evidence. The follow- genera. The reduction of the antennal arti- ing discussion must be considered indicative cles, the absence of the lateral spines on the rather than exhaustive. thorax, and the pronounced frontal tube of The relationship of Syntermes (fig. 9) has the soldier are the specialized features of been discussed by Emerson (1945) in some Procornitermes. The genus Cornitermes (fig. 9) detail. He says: "Syntermes is the most primi- is very close to Procornitermes. Several char- tive genus of the Nasutitermitinae and is acters overlap between them. Procornitermes closest to the genus Cornitermes. The relative has four to seven long spines on the inner side primitiveness is indicated by the large size of of the fore tibiae, whereas Cornitermes has 10 the imago and soldier, the relatively small or more short spines. In this character Corni- frontal tube of the soldier, the 19 to 21 arti- termes is more specialized than Procorniter- cles in the antennae of the imago and soldier, mes. In the tibial spurs also, Cornitermes is the proportionately large mandibles of the more specialized, as all its species have 2:2:2 soldier, the lateral spines or the pointed sides spurs in contrast to Procornitermes in which of the thoracic nota of the soldier, the three some species have 2:2:2 and some have 3:2:2 apical spurs on the tibiae of the forelegs, and tibial spurs. the short R1 joining the costal border a little From Procornitermes onward there are two beyond the wing suture. main branches of the phylogenetic tree of the "The closest relative outside of the sub- Nasutitermitinae (fig. 3), one represented by family Nasutitermitinae would seem to be Triacitermes and the other by Paracorni- the genus Acanthotermes of the Macrotermi- termes. The Triacitermes branch is charac- tinae. The similarities of Syntermes and terized by the narrow angle between the Acanthotermes include what seem to be homol- apical and the first marginal and a long, more ogous lateral spines on the soldier meso- or less straight, cutting edge between the two thorax and metathorax, vestiges of the lateral marginals, a pattern also present in Syn- spines on the sides of the prothorax of termes-Cornitermes. In the entire series the Acanthotermes (these spines are very small on apical is equal to, or shorter than, the first the worker of Acanthotermes but are present marginal. The Paracornitermes branch (fig. on most of the species of Syntermes), the 11), on the other hand, has a long apical white tip on the labrum of the soldier in both with a broad angle between it and the first genera (the tip of the imago labrum has a marginal, and exhibits a short but sinuate white lip in Syntermes and Pseudacantho- cutting edge between the marginals. Each termes), the postmentum of the soldier in branch illustrates various stages of evolution, 60 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 TR INERVITERMES VELOCITERMES OBTUSITERMES DIVERSITERMES TVMULITERMES AOTUNDITERMES PARVITERMES NOSPITALITERMES CEYLONITERMES LACESSITITERMES CX X TaNuIR O~~~~~~~~~~~~~~URSTR ITEME CONSTRICTOTERMES FIG. 10. Imago-worker mandibles of the subfamily Nasutitermitinae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 61 beginning in each case with soldiers that at the base (Holmgren, 1912). Moreover, have a poorly developed nasus and biting Hirtitermes has a somewhat constricted head, type of mandible and independently evolve though not so conspicuous as in the Con- the typical nasute soldier. Inasmuch as strictotermes group proper. Also the zoogeog- Procornitermes has fewer tibial spines (spines raphy of the latter is in conformity with its not to be confused with spurs) than Corni- Hirtitermes origin in the Oriental region. All termes and that the rest of the nasute genera the members of the group have the soldier do not possess spines it is likely that the head greatly produced and elevated behind dichotomy of the phylogenetic tree arose with a constriction at the base of the nasus. from Procornitermes. Longipeditermes is the most primitive among the constricted-headed genera, as the THE Triacitermes BRANCH marginal tooth on the soldier mandible would Figures 9, 10 suggest. In the unusually long antennae and Triacitermes is the most primitive genus of legs this genus exhibits convergence with this branch. Its generitype was originally de- Hospitalitermes amd Lacessititermes. Coarc- scribed under Cornitermes (Silvestri, 1901) totermes (fig. 9) probably occupies the lowest and is closely related to Procornitermes. In the position among the rest of the members of next genus, Rhynchotermes, the nasus of the this group. The apical and the first marginal soldier is much more prominent than in Tri- of the imago-worker mandibles are of the acitermes. The soldier mandibles are also more same size. The next higher genus is Grallato- slender. In the imago-worker mandibles of termes (fig. 9). Its apical is distinctly shorter Rhynchotermes the apical tooth is shorter than the first marginal. Bulbitermes (fig. 9) is than the first marginal, a character becoming placed next to Grallatotermes, as it has a little more pronounced in the higher nasutes of the more acute angle between the apical and the Triacitermes branch. first marginal. Lacessititermes and Hospita- The rest of the genera of this branch have litermes both have markedly elongate anten- a fully developed soldier nasus and frontal nae and legs. Hospitalitermes (fig. 10) has gland, and the soldier mandibles are de- undergone extreme reduction of the apical. generate and non-functional. In this complex, Constrictotermes (fig. 10) comes close to Hirtitermes is the most primitive genus, as Hospitalitermes in so far as the reduction of evidenced by the two small teeth at the base the apical is concerned. In the length of the of both soldier mandibles. antennae and legs, however, it is like Coarc- I am inclined to place Havilanditermes be- totermes-Bulbitermes. tween Hirtitermes and Nasutitermes. A possi- The rest of the nasute termites of the ble primitive character shared by all these Triacitermes branch have a swollen clypeus rather closely related genera and also by the (length half or more than half the breadth) Constnictotermes group of genera is the broad in the worker caste. Because in the primitive clypeus of the worker. The absence of any genera like Hirtitermes the clypeus is not tooth on the soldier mandible of Nasuti- markedly swollen (length less than half the termes, together with the greater proximity of breadth), I am inclined to regard the swollen the apical to the first marginal, indicates its clypeus as a more specialized character. The higher evolutionary status compared to genus Rotunditermes is relatively more primi- either Hirtitermes or Havilanditermes. Havi- tive in this grouping, as indicated by the landitermes has more reduced points on the large eyes of the imago. From Rotunditermes soldier mandible than are found in Hirti- onward there are two series of the nasute termes. genera; in one the points on the mandibles There is an indication that the Constricto- of the soldier are prominent, and in the other termes group of nasute termites has arisen they are undergoing degeneration, leading from Hirtitermes-like ancestors. One of the to their complete disappearance in Triner- constricted-headed genera, Longipeditermes, vitermes. has a small marginal tooth on the soldier In the first series (fig. 10), with the prom- mandible. In this character it shows relation- inent points on the soldier mandible, Diver- ship to Hirtitermes which has two small teeth sitermes has trimorphic, Velocitermes has 62 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 dimorphic, and Tenuirostritermes and Cey- The second series (fig. 10) presents various lonitermes have monomorphic, soldiers. This stages of soldier mandible degeneration. The sequence in the polymorphism possibly indi- loss of points on the soldier mandible begins cates the sequence in their evolution also. in some species of Parvitermes. In some indi- Tenuirostritermes (fig. 10) has an unusually viduals within the species, for example, long cutting edge between the marginals of Parvitermes pallidiceps, the loss of the point the left mandible. In the relative size of the on the soldier mandible is noticeable, while apical this genus is more primitive than others still possess the point in a rudimentary Ceylonitermes (fig. 10). condition. Further degeneration of this char- EUTERMELLUS GANULARITERMES CURVITERMES OCCASITERMES ARMITERMES CONVEXITERMES LABIOTERMES SUBULITERMES PARACORNITERMES MIMEUTERMES FIG. 11. Imago-worker mandibles'of the subfamily Nasutitermitinae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 63 acter is seen in the next genus, Tumulitermes, typical nasute soldier with functionless man- in which all members of some species have dibles. Among these genera there is further lost the point. In the proximity of the apical indication of two lines of evolution; in one to the first marginal, Tumulitermes is further the soldier mandibles still possess sharp advanced compared to Parvitermes. In Ob- points, and in the other these points have tusitermes all the species have completely been lost. lost the point. Trinervitermes exhibits ex- Angularitermes and Mimeutermes comprise treme degeneration of the soldier mandibles the first category possessing points. While which are reduced to minute knobs. the soldier mandibles are comparatively more primitive than the second series without THE Paracornitermes BRANCH points, the imago-worker mandibles are more Figure 11 specialized. On the basis of these characters The evolutionary trend in the imago- it is postulated that Angularitermes-Mimeu- worker mandibles of the members of this termes arose from the main branch at a branch is in a direction opposite to that of point earlier than Subulitermes. The an- the Triacitermes branch. Here the apical cestral stock must have possessed well- tooth is undergoing gradual enlargement, developed points on the soldier mandibles. with the accompanying widening of the angle The small marginal tooth on the right soldier between the first marginal and the apical. mandible of Angularitermes is indicative of The nasute soldiers, as in the first branch, its primitiveness relative to Mimeutermes. have evolved from the mandibulate forms. The imago-worker mandibles of Mimeu- The Paracornitermes branch is more highly termes are more specialized. The apical is evolved than the Triacitermes branch, be- larger and more curved, and the second mar- cause the imago-worker mandibles are much ginal of the right mandible is lost completely. more specialized and indicate a parallelism The rest of the genera in the Paracorni- with the Termitinae. termes branch exhibit a complete loss of the Paracornitermes is the lowest in the scale points on the soldier mandibles. Subulitermes and occupies a position corresponding to and Convexitermes, the two most closely Triacitermes in the first branch. The next related genera, have rather primitive imago- genus is Labiotermes. Armitermes manifests worker mandibles. The apical is as long as, further advance over Labiotermes. The species or a little shorter than, the first marginal, of Armitermes are relatively smaller. The and the second marginal of the right man- nasus of the soldier is more highly developed, dible is comparatively more prominent and and the mandibles are more slender and deli- thus approaches a condition somewhat like cate. that in the Triacitermes branch. But in the Curvitermes occupies a unique position. distinctly sinuate cutting edge between the Originally it was regarded as a subgenus of marginals and in the comparatively broad Armitermes and was placed close to Rhyncho- angle between the first marginal and the termes (Rhynchotermes was also considered a apical in the left mandible, these genera subgenus of Armitermes) by Holmgren (1912), should belong to the Paracornitermes branch. but the presence in Curvitermes of a combina- There is some variability in Subulitermes. tion of both primitive and specialized charac- The generitype, S. microsoma, and a group ters makes its placement in a linear order of other species of this genus have a large with the more advanced nasute genera im- apical and broad angle between the first possible. The soldier caste indicates a close marginal and the apical, while other species relationship to Armitermes, but its imago- have the Convexitermes-type of imago-worker worker mandibles have undergone great mandible, with a little more sinuate cutting specialization and show a superficial resem- edge between the marginals of the left man- blance to those of Mimeutermes, a much more dible and more reduced second marginal of highly evolved genus. Most probably Curvi- the right mandible. Occasitermes has a still termes arose from the same stock as Armi- more sinuat&e cutting edge. The width of the termes. angle between the apical and the first mar- The genera following Armitermes have a ginal of the right mandible is comparable 64 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VVOL. 95 to Convexitermes, but the same angle of the AMITERMITINAE left mandible is narrower. Eutermellus is the The subfamily name of Amitermitinae was highest evolved genus in this series. The given to the "Hamitermes-Reihe" of Holm- apical tooth is much larger than the first gren by Kemner (1934). At first I was doubt- marginal, and the second marginal of the ful of the subfamily status of the Amiter- right mandible is inconspicuous. mitinae, but the study of the imago-worker EITERIW CLOBITERMES ANOPLO7ERMES AMPHIDOTERMES mICROCEROTERMES SPECULITERMES AHAMITERMES EURYTER E HOPLOTERMES PROTOHAMITERMES FIG. 12. Imago-worker mandibles of the subfamily Amitermitinae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 65 mandibles (figs. 12, 13) clearly indicates that When the soldier caste is also known we their members form an assemblage distinct may be in a better position to understand from the Termitinae. The imago-worker the exact relationship of Protohamitermes. mandibles of all the genera of the Amiter- As this genus is the most primitive member mitinae, except the series consisting of of the Termitidae and as the latter arose Pseudomicrotermes, Synhamitermes, and Ere- from rhinotermitid-like ancestors, it is not motermes, have the apical as long as, or shorter surprising to find three marginals on the left than, the first marginal. On the other hand, mandible and an indistinct subsidiary tooth in the Termitinae all the genera (excepting on the right mandible. Neocapritermes and Planicapritermes) have The next genus, Eurytermes, and the the apical distinctly longer than the first genera following it are more specialized than marginal. The exceptional cases in both the Protohamitermes. The second marginal of the subfamilies could possibly be the result of left mandible is indicated only by a cut in convergence. front of the third marginal. The 3:2:2 ar- The imago-worker mandibles of the Ami- rangement of the tibial spurs in Eurytermes termitinae may be grouped into four main is a primitive character similar to the condi- series based primarily upon the left mandible. tion in Protohamitermes. The right mandible is essentially the same Anoplotermes is an interesting genus. This throughout except that in some genera the is the only known termite without a soldier posterior edge of the second marginal is caste. Not a single collection of this large curved and in others it is straight. genus made in the Ethiopian, the Neotropi- cal, or the Nearctic regions has so far re- THE Protohamitermes SERIES vealed the presence of the soldier, and it Figure 12 would therefore be safe to presume that The imago-worker mandibles of this series Anoplotermes has lost the soldier caste. are primitive, as indicated by the three well- Goetsch (1939), however, reports a nasute- developed marginals of the left mandible of like soldier in his captive colony of Anoplo- Protohamitermes and a distinct cut in front termes. Inasmuch as the mandibles of the of the last marginal of the left mandible in molting nymph are not figured or discussed the rest of the genera. The right mandible, (the mandibles of the worker only are listed however, is more specialized in the curved in the author's table) I am constrained not posterior edge of the second marginal. to subscribe to Goetsch's interpretation. It Homologizing the various parts of the'man- seems likely that the colony he had belonged dible I think that the last marginal of the to Armitermes, which is known to occur in left mandible is comparable to the third the same areas in South America as Anoplo- marginal, and the deep cut in front of it is termes. A study of the mandibles of this probably indicative of the second marginal. colony would easily solve this question. The tooth following the apical is unquestion- Holmgren (1912) includes Anoplotermes ably the first marginal. in the Nasutitermitinae, but because of the Protohamitermes is the most primitive close similarity of its imago-worker mandibles genus of this series. In spite of the primitive to those of Eurytermes I am following Hare imago-worker mandibles resembling those of (1937) in placing this genus in the Amiter- the Rhinotermitidae it should be regarded mitinae. The mandibles in the two genera as a member of the Amitermitinae, as are almost identical. Anoplotermes needs to originally suggested by Holmgren (1911). be revised; until then the relationships of The absence of reticulation in the wing its subgenus, Speculitermes, remain question- venation, the small forewing scales, and the able. From the evidence at hand Speculi- short pronotum of the imago and worker, termes appears to be more primitive than together with the specialized condition of Anoplotermes. The short third antennal the posterior edge of the second marginal of article and less conspicuous second marginal the right mandible, are some of the charac- of the right mandible of Anoplotermes, sensu ters indicative of a closer relationship to the stricto, indicate its higher evolutionary status Termitidae than to the Rhinotermitidae. in relation to Speculitermes. 66 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 I am placing Euhamitermes next to Ano- Cephalotermes is more primitive than Cylin- plotermes on the basis of the imago-worker drotermes because it possesses two small but mandibles alone. The fact that the imago distinct teeth in contrast to the one in caste of Euhamitermes is unknown and the Cylindrotermes. soldier of Anoplotermes does not exist makes Labritermes seems to be highly specialized it difficult to understand the exact relation- in its soldier mandibles, but the imago- ships of the two genera. Hoplotermes is con- worker mandibles are still in line with the sidered by Light (1932) to be very close to other genera of the Microcerotermes series, Eurytermes, but the study of its imago- though they too have some specialized fea- worker mandibles indicates its closer rela- tures such as the curved posterior edge of the tionship to the next genus, Ahamitermes, second marginal of the right mandible. than to Eurytermes. The reduction of the second marginal of both the mandibles and THE Pseudomicrotermes SERIES also the reduction of the length of the pos- Figure 13 terior edge of the first marginal of the left The genera belonging to this series form mandible in Euhamitermes are in contrast a well-defined group with a characteristic to the condition in Eurytermes. In Ahami- imago-worker mandibular pattern. The api- termes a further reduction of these characters cal is large and broadly separated from the is seen. first marginal; the cutting edge of the left mandible is proportionately longer than in THE Microcerotermes SERIES the Microcerotermes series, and the third Figures 12, 13 marginal of the same mandible is more re- The left imago-worker mandible in this duced. series is more specialized than in the Proto- Pseudomicrotermes is referred to the "Pseu- hamitermes series, whereas the right man- domicrotermes-Reihe" by Holmgren in his dible is more primitive. The specialized classification of the family Termitidae. In character of the left mandible is the absence his discussion of the systematic position of of the cut in front of the third marginal, Pseudomicrotermes he says that it bears re- leaving a straight edge between the mar- lationship to both the Coptotermitinae and ginals. The primitive feature of the right the Heterotermitinae of the family Rhino- mandible is the straight posterior edge of the termitidae, though at the same time possess- second marginal. ing several characters in common with Microcerotermes is least specialized among Microcerotermes of the family Termitidae. the members of this series. This is indicated The present study clearly indicates its close by the shape of the cutting edge of the left relationships with Synhamitermes and Eremo- mandible. The rest of the genera have a termes, as evidenced by the imago-worker more or less straight edge between the mar- mandibles. Synhamitermes, with a little ginals of the left mandible, and in this re- shorter and slightly curved posterior edge of spect they are more specialized than is the second marginal of the right mandible, Microcerotermes. might be considered a little more specialized Amphidotermes, on the basis of its primi- than Pseudomicrotermes. In Eremotermes the tive soldier mandible, occupies the lowest right imago-worker mandible is even more position among the genera, with the straight specialized than in Synhamitermes. However, edge between the marginals of the left man- the linear sequence of the soldier mandible dible. The next four genera have essentially is Synhamitermes, Eremotermes, and Pseudo- the same type of imago-worker mandible as microtermes. Because of the small number of Amphidotermes. Globitermes, Prohamitermes, characters showing the phylogenetic se- Cephalotermes, and Cylindrotermes are shown quence, I am tentatively placing these gen- as radiating from the same stock (fig. 12). era as radiating from a common ancestor. Cephalotermes and Cylindrotermes are more closely related to each other than to Globi- THE Amitermes SERIES termes or Prohamitermes. The shape of the Figure 13 soldier head is almost the same in the first The highest degree of specialization in the two genera. In the soldier mandible, however, imago-worker mandibles of the Amitermi- 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 67 GNATHAMITERMES LABRITERMES DREPANOTERMES CYLINDROTERMES AMI TERMES CEPHALOTERMES I. EMOTERMES PROHAMITERMES SYNIHAMITERMES PSEUDOMICROTERMES FIG. 13. Imago-worker mandibles of the subfamily Amitermitinae. 68 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 tinae is seen in the Amitermes series. The from the stock that was ancestral also to the third marginal of the left mandible is repre- other subfamilies of the Termitidae. sented only by the rounded end of the long The marked flatness of the soldier head, cutting edge. The three genera comprising with its lobed posterior end, is indicative of this series are Amitermes, Drepanotermes, a higher specialization of Planicapritermes and Gnathamitermes, radiating from the same compared to Neocapritermes. stock. Because of its zoogeographical distri- All the other genera of the Termitinae fall bution, the widely distributed Amitermes is into two main groups, one with the biting probably ancestral to the Australian Drepan- type of soldier mandible and the other otermes and the Nearctic Gnathamitermes. with the snapping type. TERM ITINAE GENERA WITH BITING TYPE OF This subfamily comprises the largest num- SOLDIER MANDIBLE ber of termite genera. The imago-worker More than half of the Termitinae genera mandibles (figs. 14-17) exhibit a gradual possess the biting type of soldier mandible. reduction of their marginals, with the ac- In this group the imago-worker mandibles companying enlargement of the apical and show various degrees of specialization. These the widening of the angle between the apical genera lend themselves to further subgroup- and the first marginal. The soldier mandibles ing. In some cases it is possible to trace a are evolving from the biting type to the linear relationship within a subgroup; in snapping type. The latter have convergently others this cannot be done. evolved twice in the subfamily. Hoplognathotermes (fig. 14) is the most Neocapritermes and Planicapritermes, primitive among the genera with biting type though possessing soldiers with strongly of soldiers. The soldier mandible is distinctly asymmetrical snapping mandibles, have the dentate. The imago-worker mandibles, how- most primitive imago-worker mandibles (fig. ever, are more specialized than those of even 14) in the subfamily. These are the only two some of the higher genera. The second genera of the Termitinae in which the apical marginal of the right mandible is greatly re- of the imago-worker mandible is small duced. The next genus, Allognathotermes and is as long as the first marginal. The (fig. 14), is very closely related to Hoplo- other primitive features are the straight gnathotermes. In the more reduced teeth of the posterior edge of the second marginal of the soldier mandible and the more reduced second right mandible and a deep cut in front of the marginal of the right imago-worker mandible, third marginal of the left mandible. The deep Allognathotermes is more specialized than cut in front of the third marginal of the left Hoplognathotermes. mandible is present in some of the Amiter- Trichotermes, Jugositermes, and Rostro- mitinae genera, such as Eurytermes, Anoplo- termes form another closely related group termes, and other members of the Protohami- (fig. 14). The last two genera have almost termes series, but in these genera the right identical imago-worker mandibles. The com- mandible is more specialized in the curved parison of the mandibles of Rostrotermes was posterior edge of the second marginal. The made from the drawings given in Grasse's fungus-growing termites of the subfamily paper (1943). Trichotermes has somewhat Macrotermitinae have imago-worker man- more primitive imago-worker mandibles than dibles somewhat as in Neocapritermes-Plani- do Jugositermes and Rostrotermes. The soldier capritermes, but the fungus growers should characters do not enable me to place Tricho- not be considered ancestral to any other termes in a linear arrangement with Jugosi- group of termites because of their extreme termes and Rostrotermes, because Tricho- biological specialization. As the possibility termes possesses a prominent frontal projec- of the evolution of the Termitinae from the tion without any ridges above the base of Nasutitermitinae is also ruled out. (because the antennae, whereas Jugositermes has very of the highly specialized soldier caste in the prominent ridges but no frontal projection. nasute genera), we may postulate that Because of the close similarity in the imago- Neocapritermes and Planicapritermes arose worker mandibles and the short but stoutly 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 69 built soldier mandibles, Trichotermes is shown forms the first branch. The soldier as well as arising from the same point as Jugositermes- the imago-worker mandibles are relatively Rostrotermes (fig. 4). Between the latter two primitive. The second marginal of the right genera, Rostrotermes is more advanced, as mandible is well developed. evidenced by the shape of the head and the Apicotermes, Crenetermes, Thoracotermes, labrum of the soldier. and Apilitermes form the second branch Next we consider a large complex of five (fig. 14). Of these genera, Apicotermes is radiating branches. Ceratotermes (fig. 14) most primitive. The soldier mandibles are APILITEFRME JGOSITERMES TRICHOTERMES THORACOM ALLOGNATIOTERMES CRENETERMES HOPLOGNATHOTERMES APICOT PLANICAPRITERMES CERATOTERMES NEOCAPRITERMES FIG. 14. Imago-worker mandibles of the subfamily Termitinae. 70 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 stout and possess small teeth. The imago- to Procubitermes. Some of the species of worker mandibles are more specialized com- Procubitermes, for instance, P. undulans pared to those of Ceratotermes, but the soldier Schmitz, show a tendency towards the evolu- mandibles are more primitive. The imago- tion of the Ophiotermes type of soldier man- worker mandibles of Crenetermes have the dible. The left mandible of P. undulans is apical more elongated than in Apicotermes. elbowed (Emerson, 1928), a character more In the length of the apical and also in the pronounced and present in both the man- stouter soldier mandibles, Thoracotermes is dibles of the Ophiotermes soldier. The imago- a little more primitive than Crenetermes, but worker mandibles of Euchilotermes are more in the shape of the soldier labrum it is more primitive than in Ophiotermes, but its soldier specialized. Apilitermes has a still more mandibles are more specialized in the ab- slender soldier mandible than either Thoraco- sence of the tooth which is present in Ophio- termes or Crenetermes. termes. The third branch is the largest and in- Tuberculitermes and Spinitermes are shown, cludes eight genera. Some of its members each by a separate branch. Tuberculitermes possess highly specialized imago-worker man- has the most highly specialized imago- dibles. The shape of the soldier labrum is, worker mandibles (fig. 15). The apical is with slight variation, the same in all these very long, slender, and curved. The man- genera. It is large, with broadly rounded to dibles of Tuberculitermes may be regarded as somewhat elongate lobes at the anterior a further specialization of the Ophiotermes end. Cubitermes and Megagnathotermes (fig. type, but the labrum character is so different 15) are shown arising from the same stock. that it seems justifiable to indicate this The large apical tooth of the imago-worker genus by a separate branch. Spinitermes mandible and the more slender soldier man- (fig. 15) has imago-worker mandibles similar dible of Megagnathotermes are indicative of to those of Ophiotermes, but because of its higher specialization compared to those of geographical distribution it is unlikely that Cubitermes, but in the shape of the labrum it belongs to the same group as Ophiotermes. and the more pronounced frontal projection Basidentitermes, Fastigitermes, and Pro- of the soldier head, Cubitermes is more ad- boscitermes form another well-defined group. vanced than Megagnathotermes. Procubi- They are shown arising from the main stem termes has more slender mandibles and a at a level slightly lower than the origin of more reduced soldier labrum than Cubi- the Ceratotermes-Spinitermes branches. Their termes. In Lepidotermes the labrum is shorter imago-worker mandibles (fig. 16) are more than in Procubitermes, is more or less flat primitive than those of any other genus with instead of being curved, and the frontal pro- a biting soldier. The second marginal of the jection is better developed. Noditermes has a right mandible is well developed and is as distinct tubercle-like projection on the post- long as the first marginal. However, in the mentum. This character probably indicates characters of the soldier, these genera are specialization. The most specialized genus highly advanced. The soldier mandibles are in the Procubitermes group is Unguitermes. delicate. Basidentitermes occupies the lowest The soldier mandible is curved in the middle, position in the group. There is no distinct and the tip is claw shaped (Sj6stedt, 1926). frontal projection of the soldier head except Ophiotermes and Euchilotermes probably for a slight elevation surrounded by a bunch arose from Procubitermes-like ancestors. This of hairs. The species of Fastigitermes are relationship is indicated by the similarity of much smaller than those of Basidentitermes, the soldier labrum. The imago-worker man- and the soldier head has a prominent frontal dibles of these two genera (fig. 15) have projection. Proboscitermes is extremely spe- undergone considerable specialization. The cialized in the development of its frontal apical is comparatively long and broadly tube. The same phylogenetic sequence is curved, the second marginal of the right manifest in the labrum of the soldier. mandible is completely lost and of the left Orthotermes (fig. 16) appears to be an mandible is weakly developed. Of these two offshoot from Basidentitermes. The imago- genera, Ophiotermes is more closely related worker mandibles and the soldier labrum are 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 71 NODITERMES TUBERCULITERMES LEPIDOTERMES SPINITERMES PROCUBITERMES OPHIOTERIES CUBITER EUCHILOTER HIS MEGAGNATHOTERMES UNUITE FIG. 15. Imago-worker mandibles of the subfamily Termitinae. 72 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 slightly more specialized than in Basidenti- ized than Angulitermes, as evidenced by the termes. loss of the second marginal on both of the imago-worker mandibles. In the soldier the GENERA WITH SNAPPING TYPE OF highly developed frontal projection with a SOLDIER MANDIBLE depression in the middle of the head is a The snapping type of soldier probably further indication of the higher evolutionary arose from the biting type. The close simi- status of Cavitermes. larity of the imago-worker mandibles of Crepititermes has imago-worker mandibles Promirotermes (fig. 16), the most primitive (fig. 16) very much as in Cavitermes except genus possessing snapping soldiers, and those that the apical is not so long. Crepititermes of Basidentitermes with biting type of soldier, probably represents a side branch from the is suggestive of an evolutionary sequence. main branch leading to Cavitermes. Because The snapping group is further branched into of the flat soldier head without any frontal two main lines, one with relatively sym- projection this genus cannot be considered metrical snapping mandibles and the other ancestral to Cavitermes. with various degrees of asymmetrical snap- The genera with various degrees of asym- ping mandibles. metrical soldier mandibles are most probably Orthognathotermes appears to be an early derived from the group with symmetrical offshoot from the branch which later gave soldier mandibles. Among the latter the rise to the termites with symmetrical snap- closest relative appears to be Promirotermes. ping soldier mandibles. The soldier mandibles This relationship is indicated by the close of this genus still serve the function of biting similarity of the imago-worker mandibles as well as snapping. It should not, however, of Promirotermes and Paracapritermes (fig. be considered ancestral to other snapping 17). forms because its imago-worker mandibles Paracapritermes, Quasitermes, Mirocapri- (fig. 16) are more specialized than those of termes, and Cornicapritermes still share the the next genus, Promirotermes, which has frontal projection of the previous group. typical snapping soldier mandibles. The Paracapritermes and Quasitermes have es- well-developed second marginal of the right sentially the same type of imago-worker mandible and the equally well-developed mandible (fig. 17), except that Quasitermes third marginal with an anterior deep cut in has a little more reduced second marginal on the left mandible are indicative of the both the mandibles and a shorter posterior primitiveness of Promirotermes. edge of the first marginals of the left man- Spicotermes comes next to Promirotermes dible. The imago-worker mandibles of Miro- in the phylogenetic sequence. It has more capritermes (fig. 17) are more specialized than specialized imago-worker mandibles (fig. 16) in Quasitermes. Cornicapritermes has still and a more pronounced frontal projection of more specialized imago-worker mandibles, the soldier head. In Termes (= Mirotermes) as indicated by the reduction of the second the frontal projection of the soldier head is marginal of the right mandible, but it is more pronounced than in Spicotermes. Also more primitive in the presence of a distinct in the imago-worker mandibles (fig. 16) cut in front of the third marginal of the left Termes shows advance over Spicotermes. The mandible. second marginal of the right mandible is The last six genera, viz., Homallotermes, more reduced and the cutting edge between Pericapritermes, Capritermes, Procapritermes, the two marginals of the left mandible is Protocapritermes, and Pseudocapritermes, shortened. The same mandibular pattern is have lost the frontal projection, but the seen in Angulitermes (fig. 16) also, which strongly asymmetrical mandibles of the suggests the possible origin of this genus soldier are retained. This group is shown from Termes. The soldier mandibles of arising from Paracapritermes because of the Angulitermes are more slender than those of resemblance of the imago-worker mandibles Termes, and the frontal projection is also to those of Homallotermes. The loss of the more prominent. frontal projection may have occurred sec- Cavitermes (fig. 16) is much more special- ondarily. Judging from the shape of the 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 73 XAVITERMES ORTHOGNATNHOTERMES CREPITITEFkMES ORTHOTERMES ANGULITERMES PROBOSCITERMES TERMES FASTIG4TERMES SPICOTERMES BASIDENTITERMES PROMIROTERMES FIG. 16. Imago-worker mandibles of the subfamily Termitinae. 74 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 HOMALLOTERMES PSEUOOCAPRITERMES PROCAPRITERMES CORNICAPRITERMES CAPRITERMES MIROCAPRITERMES PROTOCAPRITEFLMES QUASITERMES PERICAPRITERMES PARACAPRITERMES SERRITERMES FIG. 17. Imago-worker mandibles of the subfamilies Termitinae and Serritermitinae. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 75 second marginal of the right mandible of treat the Serritermitinae as a subfamily of Pericapritermes, it seems likely that this the Termitidae because of the highly spe- genus is derived from Homallotermes. The cialized imago-worker mandibles (fig. 17). next genus is Protocapritermes. The second I consider the soldier mandibles also to be marginal of the right mandible of Protocapri- highly specialized. The serration of the man- termes is less prominent than in Pericapri- dibles is quite distinct from the condition in termes. The following two genera, Capri- Heterotermes and even in Microcerotermes, the termes and Procapritermes, are very closely only other genera having serrated soldier related to each other. In the rather straight mandibles. Other specialized characters of posterior edge of the first marginal of the the Serritermitinae are the 2:2:2 tibial spur left mandible, Pseudocapritermes appears to arrangement, the absence of styli, and the be a little more advanced than Procapri- reduction of the median in the wing. termes. Most of the Termitidae have a 2:2:2 tibial spur arrangement and lack styli. The SERRITERM ITINAE large pronotum and the forewing scales of the Serritermitinae that in the opinion of The Serritermitinae, represented by a Holmgren justify their inclusion in the single genus, Serritermes, were regarded as a Rhinotermitidae also are present in some of subfamily of the Rhinotermitidae by Holm- the primitive members of the Termitidae gren (1911). The primitive characters of the such as Protohamitermes. Moreover, not all Serritermitinae, which probably led Holm- the Rhinotermitidae possess these charac- gren to include them in the Rhinotermitidae, ters. Psammotermes and Reticulitermes have include the large pronotum, the large fore- short pronota and short forewing scales. The wing scales, and the reticulated appearance inclusion of the Serritermitinae in the of the wing membrane. Holmgren considers Rhinotermitidae would mean a sudden and the serration of the soldier mandible to be an extreme specialization of the otherwise primitive. Within the Rhinotermitidae he fairly fixed pattern of the imago-worker thinks the Heterotermitinae are the closest mandibles. relatives of the Serritermitinae, on the basis On the basis of this discussion I am trans- of the large clypeus of the imago, and the ferring the Serritermitinae to the Termitidae. serration of the soldier mandible, but be- The characters of Serritermes are distinctive cause of the presence of the rudimentary enough to retain a subfamily rank. The more eyes in the soldier caste, he shows this sub- primitive relatives of Serritermes that might family as an early branch from the Hetero- clarify its evolution seem to have become termitinae stem. I am, however, inclined to extinct. DISCUSSION LONG BEFORE THE BIRTH of the theory of In an approach to the study of phylogeny evolution it was recognized by naturalists via morphology the chances of error are that organisms could be grouped on the basis greatly minimized if we base our study on of their common anatomic and morphologic conservative characters. In termites the attributes. The question as to why members mandibles of the imago and worker provide of such a "natural" group possess these such a character. There is no indication that common characteristics remained unanswered the various types of mandibular pattern until 1859 when Darwin in his theory of discussed here have any adaptive value. evolution provided the plausible explana- Termites eating the same kind of food may tion. According to the theory of evolution the have different types of imago-worker man- similarity among the members of a natural dibles. For example, Hodotermes (Hodoter- group is the result of their descent from a mitinae), Trinervitermes (Nasutitermitinae), common ancestor. "Structural similarity due and Amitermes (Amitermitinae) may eat the to common ancestry" is the underlying idea same grass, yet they possess dissimilar mandi- behind the concept of homology. The phylo- bular patterns. The three genera of the genetic attribute of homology was, however, Termopsinae feed on damp, rotten logs, but not implied by Owen (1843) who originally their imago-worker mandibles are different. coined this term. The science of genetics On the other hand we find the same mandibu- has contributed a great deal towards the lar pattern in some termites with different understanding of the phylogenetic implica- food habits. Syntermes and some species of tions of homology. Wright (1934), giving the Nasutitermes having entirely different ecolog- genetic interpretation of homology, says: ical adjustments, one excavating soil and "The same, or similar, gene complexes may feeding on leaves, the other constructing be expected to come into play wherever arboreal nests and feeding on wood, both sufficiently similar conditions arise in differ- possess the same type of imago-worker ent parts of the developing pattern, giving mandible. It is therefore obvious that the bilateral, metameric or other replicative different sizes of the cutting edges or the homologies within the organism. In different angles between them have no direct adaptive but phylogenetically related organisms, more value. The development of the mandibular or less similar gene complexes tend to come pattern of the imago and worker castes is into play in corresponding parts of the growth most likely initiated by complex gene pat- patterns, which are thereby kept developing tern that also influences the growth of other along similar lines." characters, some of which may have Recently Boyden (1947) has advocated adaptive values. A change in the genetic the restriction of the idea of homology to complex under the stress of selection that originally conceived by Owen. He com- pressure need not necessarily result in a ments: "The original and necessary concept corresponding adaptive change in the man- in homology is essential structural similarity. dibular pattern. Adaptive changes in the The secondary meaning for homology of soldier caste, i.e., the evolution of the nasute common phylogenetic origin has no place in soldier from the mandibulate soldier in the serial homology and a role of secondary im- Nasutitermitinae or the evolution of the portance in special homology." By special minor soldier in the Rhinotermitinae, are homology is meant "the structural agreement not correlated with changes in the mandibu- of corresponding parts of the bodies of dif- lar pattern of the imago-worker. Here we ferent organisms." In the light of the genetic have a character which is under the least interpretations given by Wright there ap- direct selection pressure. Change, when it pears to be no difficulty in deducing phylo- does occur, is consequently of great phylo- genetic relationships from the study of serial genetic significance. homology as well. Similarity of gene com- A character like that of the soldier man- plexes must be assumed in explaining homol- dible has strikingly different functions in ogy whether serial or special. different groups of termites. Any phylo- 76 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 77 genetic conclusions based on such a charac- evolved the strongly asymmetrical soldier ter might be erroneous because the exact mandibles similar in function to those in the phylogenetic relationship would be obscured Capritermes group. An examination of their by convergent adaptation. Sometimes serious imago-worker mandibles indicates the ex- mistakes have been made by confusing treme primitiveness of the Neocapritermes analogy with homology. A distinction be- branch not seen in any other genus of the tween the two phenomena is by no means subfamily. easy, particularly in closely related organ- Parallelism, which means the evolutionof isms. "The separation of analogous from the "adaptive characters" among the "mem- homologous morphological characters throuh bers of different families of the same ordinal the maze of genetic modifications, physi- heritage" (Gregory, 1936), has also occurred ological influences, growth patterns, de- in termite evolution. The soldier caste of generative changes, and convergent adapta- Stylotermes (of the family Rhinotermitidae) tions, is a difficult task" (Emerson, 1938). bears a close resemblance to the soldier The present study reveals several cases of caste of Kalotermes (of the family Kaloter- convergence in the phylogeny of termites. mitidae). It was this parallelism which led The phragmotic head is a defense adaptation Holmgren and Holmgren (1917) to think that in plugging the holes of the nest. The evolu- "Stylotermes can be connected directly to tion of the extreme phragmotic head in the Calotermes, and exhibits an essentially dis- family Kalotermitidae has taken place three tinct link" between the families Kalotermiti- times (Cryptotermes, Eucryptotermes, and dae and Rhinotermitidae. Calcaritermes). On the basis of the soldier The imago-worker mandible in termites characters these three genera could easily exhibits various stages of regressive evolution be grouped together, but the imago-worker from the roach-like mandible to the highly mandibles and the wing venation indicate specialized type seen in the Serritermitinae that Cryptotermes has evolved independently in which an extreme reduction of the mar- of the Glyptotermes branch, and extreme ginals of both the mandibles has occurred. phragmosis has appeared twice from the Such a reduction also has taken place in the less specialized Glyptotermes-like ancestry. soldier mandibles of the nasute termites. Such a convergent evolution of the phrag- The best example of progressive regression in motic head also has taken place in unrelated the imago-worker mandibles is furnished by ants (Colobopsis and Cryptocerus; Wheeler, the subfamily Termopsinae, in which a 1928). gradual regression of the second marginal Some of the best examples of convergence of the left mandible has taken place. This among the termites are found in the sub- regression is most probably due to the slow family Nasutitermitinae. The two main accumulation of many small mutations. In branches of the tree have independently other cases where no progressive regression evolved the characteristic nasute soldiers. is exhibited, one need not necessarily con- In previous classifications a large number of clude that the reduction has been brought subgenera were included under Nasutitermes about in a single step, although somewhat (Holmgren, 1912), and Hill (1942) was so similar instances of morphological modifica- confused about the status of these subgenera tions are not rare in Drosophila bred in the that he treated all of them as Nasutitermes genetics laboratory. Next to Armitermes (=Eutermes). This uncertainty with regard with biting type of soldier mandible in the to the status of the various subgenera of Paracornitermes branch of the Nasutiter- Nasutitermes has been solved, to some extent, mitinae is placed A ngularitermes with de- by the study of the imago-worker mandibles. generate mandibles characteristic of a nasute All Holmgren's subgenera should now be soldier. This big gap between the two genera treated as genera. Many of them belong to is best explained as the result of extinction different phylogenetic lineages (fig. 3). of the intermediate forms or the lack of Another very striking example of con- their discovery. vergence is seen in the subfamily Termitinae. When the phylogeny of the family Hodo- Neocapritermes and Planicapritermes have termitidae was discussed, mention was made 78 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 of the subsidiary tooth at the base of the In some respects the social insects provide anterior edge of the first marginal of the better material for phylogenetic studies than right imago-worker mandible. This charac- non-social organisms. In termites, for instance, ter, apparently functionless, has probably one has at his disposal a large number of existed in some termites for millions of years. morphological characters in the differentiated It may therefore be logical to think in terms castes upon which to base his phylogenetic of the persistence of genes and gene patterns, conclusions. The soldier, worker, and the an idea originally conceived by Emerson imago, which are so different morphologically (unpublished). This property of some genes and could be comparable in this respect to may also be inferred from the genetic ex- three unrelated organisms, are nevertheless planation given to the phenomenon of ata- members of a single unit, or supraorganism vism. In connection with the appearance of (Emerson, 1939). We can draw material for the little toe in the hind foot of the guinea study from any of the castes, and we shall pig, Wright (1934) remarks that this charac- still be dealing with the same organism unit. ter "if not wholly novel in the phylogeny at The polymorphism of the soldier caste has least has emerged from the depth after mil- been of help in understanding the relation- lions of years." The genes responsible for ships of some termite genera. Dimorphic this character have persisted through long soldiers appear first in the family Rhinoter- geological time. "A change of timing within mitidae. Among the entire Order Isoptera the development system, a change which these genera (Schedorhinotermes, Rhino- might remain intact over eons" (Goldschmidt, termes, and Dolichorhinotermes) exhibit the 1946) causes the suppression of an organ or most obvious functional dimorphism. The part of an organ. If this change is itself minor soldier has evolved a gas-defense under the control of genes, which is most mechanism. The labrum is considerably probably true, then we must believe in the elongated and the mandibles are very much persistence of genes during long evolutionary reduced as compared to the major soldier periods. which possesses the biting type of mandible. Throughout this study Dollo's rule of ir- The minor soldiers of these genera and the reversibility of evolution has been found nasute termites of the subfamily Nasutiter- applicable. An organ, after having undergone mitinae exhibit a convergent reduction of regression, does not appear again. However, the mandibles in association with the evolu- if the character is genetically simple it is tion of an enhanced defense function. possible that reappearance may occur. Re- In the subfamilies Macrotermitinae and verse mutations have been demonstrated by Nasutitermitinae many genera have tri- geneticists. On the other hand if the charac- morphic or dimorphic soldiers. The relation- ter is under the control of a gene complex, as ships of these have been determined by a most taxonomic characters are, the proba- comparison of numerous morphological char- bility of reappearance after loss would be acters, and it may be assumed that derived very slight. In such cases full reversion can monomorphic forms are more specialized take place only if many genes mutate back than the polymorphic forms. at the same time, thus restoring the original In many genera a better understanding of homologous gene complex. Such an event the relationships was made possible by the seems to be an impossibility for genetically study of the zoogeographical data. Spini- complex characters. Discussing irreversibility termes and Tuberculitermes have very similar from the viewpoint of genetics, Muller (1939) imago-worker mandibles, on the sole basis says: "There can be apparent reversal of of which a close phylogenetic lineage might evolution with respect to given characters have been assumed, but their geographical brought about by selection of mutations as distribution is hardly compatible with such well as by the genetic disintegration at- a relationship. Spinitermes is known from tendant upon mere removal of selection. But South America and Tuberculitermes from in neither case will the final product be Africa. Again, in the evolution of the Con- genetically identical or even very similar to strictotermes group of the nasute termites the archetype." from the Hirtitermes branch, assistance was 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 79 sought from the zoogeographical data. The number of cases which are difficult to explain distribution of some of the primitive ter- by means of the known principles of animal mites, such as Mastotermes, Stolotermes, and geography. The present study has, in a few Porotermes, conforms to Matthew's theory cases, cleared some difficulties; others still of distribution of the primitive forms. remain a problem for those interested in Schmidt (1943), explaining Matthew's theory, zoogeography. says, "Australia, South America and the The phylogenetic scheme of the termite southern half of Africa project southward genera presented in this paper gives a broad from the northern continents like great perspective of relationships and is an im- peninsulas, and as the more primitive forms provement over previous schemes. No phylo- enter them at the north, they have neces- genetic conclusions can approach perfection sarily accumulated in these peninsulas from unless based upon evidence derived from successive waves of dispersal, and of evolu- various phases of biology, such as embryol- tion." The most primitive termite, Masto- ogy, genetics, physiology, behavior, ecology, termes, is now confined to Australia. Its fossil and zoogeography. Future discoveries will history reveals its former much wider distri- doubtless result in the modification of the bution in Europe and North America. Poro- phylogenies here postulated, but it is hoped termes is recorded from Australia, Tasmania, that the relationships suggested by this New Zealand, the Cape Province in South study will be verified far more often than Africa, and Chile. There is, however, a large they will be refuted. SUMMARY 1. THE PHYLOGENY of 139 out of a total of subgenera are best raised to generic rank. 142 genera and subgenera of termites based 8. Pseudomicrotermes, whose exact rela- primarily upon the imago-worker mandibles tionship has thus far remained obscure, is has been studied. now assigned to the subfamily Amitermi- 2. The imago-worker mandibles of ter- tinae in which it forms a distinct group with mites provide a conservative morphological Eremotermes and Synhamitermes. character significant for the study of phy- 9. There are several instances of conver- logeny. gence in termite evolution. The phragmotic 3. The families Kalotermitidae and Rhino- head in the Kalotermitidae has evolved three termitidae have a relatively fixed mandibular times. The nasute soldier in the Nasutiter- pattern in the imago and worker castes. The mitinae has arisen twice independently. The Hodotermitidae and the Termitidae exhibit evolution of the asymmetrical soldier man- a great variation in the imago-worker man- dibles in the Termitinae has occurred in two dibles. The variation of this character within distantly related groups of genera. a genus is negligible. 10. Zoogeography has been of some help 4. In the main, this study corroborates the in understanding the phylogenetic relation- termite classification proposed by Holmgren. ships of several genera. The distribution of In some cases, however, he has misinter- some primitive termites belonging to the preted the phylogeny because of convergent families Mastotermitidae and Hodotermiti- adaptation. The study of the imago-worker dae conforms to Matthew's theory of distri- mandibles has cleared some of these errors. bution of primitive forms. 5. The subfamily Serritermitinae, hitherto 11. The worker caste, usually considered included under the family Rhinotermitidae, of little importance in termite taxonomy, is transferred to the family Termitidae. can be of great value for generic identifica- 6. It is concluded that the Rhinotermiti- tion, particularly by the study of its man- dae arose from a stock which had Archoter- dibles. mopsis-like imago-worker mandibles and 12. A discussion of the concepts of homol- possessed ocelli and not from the Kaloter- ogy, conservative characters, convergence, mitidae as suggested by Holmgren and Hare. Dollo's rule of irreversibility of evolution, 7. There are several phylogenetic lineages regressive evolution, and the persistence of in the Nasutitermitinae, and Holmgren's genes and gene patterns has been included. 80 APPENDIX THE DRAWINGS of the imago-worker man- det. A. Emerson, Talcahuana, Chile, coll. Stein- dibles (figs. 5-17) are based on the following dachner, IV. 1873. species: 18. Stolotermes brunneicornis (Hagen), dealate, det. G. F. Hill, comp. A. Emerson, Adventure ROACHES Bay, Brunn Island, Tasmania, 14. IV. 1935. 1. Ancaudellia serratissima (Brunner), Firsch 19. Hodotermes mossambicus Hagen, worker, Haven, New Guinea, coll. Hebard. det. F. Silvestri, Windhuk, southwest Africa. 2. Panesthia angustipennis (Illig), Solka boeni, 20. Microhodotermes viator (Latreille), worker, Java. det. F. Silvestri, redet. A. Emerson, Steinkop, 3. Cryptocercus punctulatus Scudder, Glendale, Little Namaland, Africa. Douglas County, Oregon. 21. Anacanthotermes ochraceus (Burmeister), worker, det. and coll. A. Emerson, Kairouan, TERMITES Tunisia, I. XI. 1926. 4. Mastotermes darwiniensis Froggatt, nymph, 22. Psammotermes hybostoma Desneux, imago, det. G. F. Hill, metatype, comp. A. Emerson, det. and comp. A. Emerson, Temassinini, Algeria, Townsville, north Queensland, Australia, coll. coll. v. Geyr, 29. I. 1914. F. H. Taylor. 23. Coptotermes gestroi (Wasmann), worker, 5. Kalotermesflavicollis (Fabricius), imago, det. det. N. Holmgren, metatype, comp. A. Emerson, N. Holmgren, Italy, from Light collection, no. Dibrugarh, Assam, India, coll. C. C. Ghosh, 240 It. 26. X. 1911. 6. Procryptotermesfryeri Holmgren, imago, det. 24. Heterotermes paradoxus (Froggatt), worker, N. Holmgren, cotype from type colony, Taka- det., comp., and coll. G. F. Hill, Townsville, maka, Aldabra Island, coll. J. C. F. Fryer, 6. north Queensland, Australia, II. 1922. X. 1908. 25. Reticulitermesflavipes Kollar, worker, meta- 7. Cryptotermes cavifrons Banks, imago, det. type, det. and comp. A. Emerson, Tampa, Florida, and coll. T. E. Snyder, metatype, comp. A. Emer- coll. Ricter, 27. XI. 1936. son, Florida, 24. III. 1917. 26. Stylotermes fletcheri Holmgren, worker, co- 8. Paraneotermes simplicicornis (Banks), imago, type, det. N. Holmgren, Coimbatore, India, coll. det., coll., and comp. A. Emerson, Edoni, Cali- T. B. Fletcher, 11. X. 1912. fornia, 8. IX. 1929. 27. Termitogeton umbilicatus (Hagen), worker, 9. Neotermes castaneus (Burmeister), imago, det. H. Hagen, Rambodda, Ceylon. det. A. Emerson, Pine Crest, Monroe County, 28. Prorhinotermes simplex (Hagen), worker, Florida, coll. E. M. Miller, 12. X. 1940. det. A. Emerson, Miami, Florida, coll. W. 10. Rugitermes nodulosus (Hagen), imago, det. Murphy, 10. II. 1935. A. Emerson, Ilha Grande, Brazil, coll. H. Muth 29. Parrhinotermes aequalis (Haviland), worker, and H. Sick, IX. 1944. det. N. Holmgren, metatype, comp. A. Emerson, 11. Glyptotermes tuberculatus Froggatt, imago, Selangor, Malacca, coll. H. v. Buttel-Reepen, det. G. F. Hill, metatype, comp. A. Emerson, III. 1912. Takapuna, Aukland, New Zealand, coll. J. M. 30. Schedorhinotermes intermedius (Brauer), Kelsey. worker, metatype, plesiotype, det. W. W. Frog- 12. Calcaritermes nigriceps (Emerson), imago, gatt, comp. A. Emerson, New Castle, New South autotype, metatype, det. and comp. A. Emerson, Wales, Australia. Salybia Bay, Trinidad, coll. A. M. Adamson, 31. Rhinotermes marginalis (Linn6), worker, 12. X. 1940. plesiotype, det. and comp. A. Emerson, Kartabo, 13. Eucryptotermes hageni, Fr. Muller, imago, British Guiana, 20. IX. 1920. det. and coll. Fr. Muiller, Brazil. 32. Dolichorhinotermes longilabius (Emerson), 14. Archotermopsiswroughtoni Desneux, nymph, worker, paratype, det. and coll. A. Emerson, autotype, metatype, det. and comp. J. Desneux, Kartabo, British Guiana, 23. VI. 1920. Kashmir Valley, India, coll. E. Radcliff. 33. Acanthotermes acanthothorax Sjostedt, 15. Hodotermopsisjaponicus Holmgren, nymph, worker, det. and comp. A. Emerson, Akenge, det. N. Holmgren from type colony, Loo-Choo Belgian Congo, IX. 1913. Archipelago, coll. Watase, 16. IV. 1909. 34. Pseudacanthotermes militaris (Hagen), 16. Zootermopsis angusticollis (Hagen), imago, worker, det. A. Emerson, Malela, Belgian Congo, det. T. E. Snyder, Redwood, California, coll. R. Lang-Chapin coll., 4. VII. 1915. Hopping, 29. VIII. 1918. 35. Synacanthotermes heterodon Sjostedt, work- 17. Porotermes quadricollis (Rambur), imago, er, cotype, det. Y. Sjbstedt, Cameroon. 81 82 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 36. Macrotermes goliath (Sj6stedt), imago, meta- son, Lake Casili, Luzon, Philippines, coll. R. C. type, det. and comp. A. Emerson, Mt. Selinda, McGregor and S. F. Light, 23-25. X. 1920. Rhodesia, coll. R. Boulton, 13. XII. 1929. 55. Bulbitermes constrictus (Haviland), worker, 37. Allondontermes rhodesiensis (Sj8stedt), metatype, det. and comp. A. Emerson, Sandakan, imago, det. F. G. M. Westropp, Msugaa, Tangan- Borneo, coll. K. P. Schmidt, 8. VII. 1929. yika, coll. E. Burtt, 3. XII. 1935. 56. Constrictotermes cyphergaster (Silvestri), 38. Protermes prorepens (Sj6stedt), worker, worker, metatype, topotype, det. and comp. A. metatype, det. and comp. A. Emerson, Stanley- Emerson, Matto Grasso, Brazil, coll. K. P. ville, Belgian Congo, coll. P. Kohl. Schmidt, 20. VIII. 1926. 39. Sphaerotermes sphaerothorax Sjostedt, meta- 57. Lacessititermes batavus Kemner, worker, type, morphotype, det. and comp. A. Emerson, paratype, det. and coll. N. A. Kemner, Depok, near Stanleyville, Belgian Congo, coll. H. Kohl. Java, X. 1920. 40. Odontotermes (Odontotermes) vulgaris (Havi- 58. Hospitalitermes hospitalis (Haviland), land), worker, metatype, det. and comp. A. Emer- worker, cotype, det. and coll. G. D. Haviland, son, Tylden, Cape Province, Africa. Sarawak, Borneo. 41. Odontotermes Hypotermes) xenotermitis 59. Rotunditermes rotundiceps Holmgren, Holmgren, worker, metatype, det. and comp. A. worker, cotype, det. and coll. N. Holmgren, Emerson, Shillong, Assam, India, coll. C. C. Chaquimayo, Peru, 23. XII. 1904. Ghosh. 60. Diversitermes diversimilis (Silvestri), worker, 42. Ancistrotermes crucifer Sj6stedt, worker, det. T. E. Snyder, metatype, comp. A. Emerson, det. A. Emerson, Njala, Sierra Leone, coll. Har- Espia, Bolivia, coll. W. M. Mann, 7. VIII. 1921. greaves, 24. VII. 1930. 61. Velocitermes beebei Emerson, worker, topo- 43. Microtermes calvus Emerson, worker, para- type, autotype, metatype, det. and coll. A. Emer- type from type colony, St. Gabriel, near Stanley- son, Kartabo, British Guiana, 19. VI. 1924. ville, Belgian Congo, coll. T. Kohl. 62. Tenuirostritermes tenuirostris (Desneux), 44. Syntermes dirus (Burmeister), worker, det. worker, det. A. Emerson, Phantom Lake, Davis A. Emerson, Ilha Grande, Brazil, coll. H. Muth Mts., Texas, coll. F. M. Gaige, 8. VII. 1916. and H. Sick, 12. VI. 1944. 63. Ceylonitermes escherichi (Holmgren), 45. Procornitermes striatus (Hagen), worker, worker, cotype, det. N. Holmgren, Peradenyia, plesiotype, det. and coll. F. Silvestri, La Sierra, Ceylon, coll. Escherich. Uruguay, V. 1899. 64. Parvitermes discolor (Banks), worker, meta- 46. Cornitermes cumulans (Kollar), worker, type, det. and comp. A. Emerson, Caribbean Na- metatype, det. and comp. A. Emerson, Leme, Slo tional Forest, Puerto Rico, coll. J. A. Ramos, 4. Paulo, Brazil, coll. R. L. Araujo and D. Braz, IV. 1947. 13. IX. 1944. 65. Tumulitermes pastinator (Hill), worker, 47. Triacitermes triacifer (Silvestri), worker, paratype, det. and coll. G. F. Hill, Darwin, det. A. Emerson, Lins, Sao Paulo, Brazil, coll. R. Australia, 14. XI. 1913. L. Araujo, 24. XI. 1944. 66. Obtusitermes panamae Snyder, worker, auto- 48. Rhynchotermes nasutissimus (Silvestri), type, det. and coll. T. E. Snyder, Barro Colorado worker, cotype, det. and coll. F. Silvestri, Villa Island, Panama Canal Zone, 26. II. 1924. Rica, Paraguay, X. 1900. 67. Trinervitermes trinervius (Rambur), worker, 49. Hirtitermes spinocephalus Oshima, worker, det. A. Emerson, Liberia, coll. Scherer, 1908. cotype, det. M. 0. Oshima, Tarakan, Dutch 68. Paracornitermes laticephalus Silvestri, Borneo, coll. R. Kenehira, 23. V. 1913. worker, cotype, det. and coll. F. Silvestri, Coxipo, 50. Havilanditermes atripennis (Haviland), Brazil, 8. IX. 1900. worker, coll. G. D. Haviland, Sarawak, Borneo. 69. Labiotermes labralis Holmgren, worker, 51. Nasutitermes corniger (Motschulsky), im- metatype, det. and comp. A. Emerson, St. Gabriel, ago, det. and coll. A. Emerson, Galeta Island, Rio Negro, Brazil, coll. A. Roman, 3. I. 1924. Panama Canal Zone, 23. V. 1935. 70. Armitermes armiger (Motschulsky), worker, 52. Longipeditermes longipes (Haviland), metatype, det. and comp. A. Emerson, Barro worker, metatype, det. and comp. A. Emerson, Colorado Island, Panama Canal Zone, 13. IV. Sandakan, Borneo, coll. K. P. Schmidt, 8. VII. 1935. 1929. 71. Curvitermes odontognathus (Silvestri), 53. Coarctotermes clepsydra (Sj6stedt), worker, worker, cotype, det. and coll. F. Silvestri, Coxipo, det. A. Emerson, Madagascar, coll. H. Kirby, no. Brazil. T-4475. 72. Angularitermes nasutissimus Emerson, 54. Grallatotermes splendidus Light and Wilson, worker, paratype, det. and coll. A. Emerson, worker, paratype, det. S. F. Light and F. J. Wil- Kartabo, British Guiana, 11. VII. 1920. 1950 AHMAD: PHYLOGENY OF TERMITE GENERA 83 73. Mimeutermes giffardii Silvestri, worker, co- 92. Pseudomicrotermes alboniger (Wasmann), type, det. and coll. F. Silvestri, Camayenne, worker, cotype, det. E. Wasmann, Sankura (Kas- French Guiana, 28. X. 1912. sai), Belgian Congo, coll. Luja, X. 1905. 74. Subulitermes oculatissimus Emerson, imago, 93. Synhamitermes quadriceps Wasmann, paratype, from holotype colony, det. and coll. A. worker, cotype, det. E. Wasmann, Khandala, Emerson, Kartabo, British Guiana, 26. IX. 1920. Bombay, India, coll. J. Assmuth, 75. Convexitermes manni Emerson, worker, 94. Eremotermesfletcheri Holmgren, worker, co- metatype, autotype, det. and comp. A. Emerson, type, det. N. Holmgren, Coimbatore, India, coll. Oronoque River, British Guiana, coil. N. Weber, T. B. Fletcher, 12. V. 1912. 30. VII. 1936. 95. Amitermes amifer Silvestri, worker, det. 76. Occasitermes occasus (Silvestri), imago, det. and coll. F. Silvestri, Coxipo, Brazil, VII-IX. G. F. Hill, Dwellingup, southwest Australia, 8. 1900. VII. 1920. 96. Drepanotermes rubriceps (Froggatt), worker, 77. Eutermellus convergens Silvestri, worker, co- cotype, from type colony, det. A. Emerson, Tam- type, det. F. Silvestri, Fernando Po River, Africa, min, west Australia, coll. Clark. coll. Fea. 97. Gnathamitermes perplexus (Banks), worker, 78. Protohamitermes globiceps Holmgren, imago, metatype, det. and comp. A. Emerson, Arizona, cotype, det. N. Holmgren, Sarawak, Borneo, coll. 18. IV. 1937. G. D. Haviland. 98. Neocapritermes angusticeps Emerson, imago, 79. Eurytermes assmuthi Wasmann, worker, co- paratype, from type colony, det. and coll. A. type, det. E. Wasmann, Khandala, Bombay, Emerson, Kartabo, British Guiana, 9. IV. 1924. India, coll. J. Assmuth. 99. Planicapritermes planiceps (Emerson), 80. Speculitermes cyclops Wasmann, worker, worker, paratype, from type colony, det. and coll. cotype, det. E. Wasmann, Khandala, Bombay, A. Emerson, Kartabo, British Guiana, 11. V. 1919. India, coll. J. Assmuth, 12. V. 1902. 100. Hoplognathotermes furcatus Sjostedt, im- 81. Anoplotermes pacificus Muller, imago, meta- ago, cotype, det. Y. Sj6stedt, Nola Baria, Belgian type, det. and comp. A. Emerson, Ilha Grande, Congo, coll. G. Erikson, 1924. Brazil, coll. H. Muth and H. Sick, 29, XI. 1944. 101. Allognathotermes hypogeus Silvestri, 82. Euhamitermes indicus Holmgren, worker, worker, cotype, det. and coll. F. Silvestri, Ka- cotype, det. N. Holmgren, Shevaroy Hills, India, koulima, Africa, 12. VIII. 1912. coll. T. B. Fletcher, 16. X. 1912. 102. Trichotermes villifrons Sj6stedt, worker, 83. Hoplotermes amplus Light, worker, det. and metatype, det. and comp. A. Emerson, Mukim- coll. S. F. Light, Jala, Colima, Mexico, I. 1930. bungu, Belgian Congo, coll. Laman, 19. X. 1904. 84. Ahamitermes hilli Nicholls, worker, para- 103. Jugositermes tuberculatus Emerson, type from type colony, det. and coll. Nicholls, worker, metatype, autotype, det., comp., and coll. Kalgoorlie, Australia, 20. III. 1928. A. Emerson, Epulu, Belgian Congo, 20. V. 1948. 85. Microcerotermes strunckii (Sorensen), 104. Ceratotermes sp., imago, det. and coll. A. worker, metatype, plesiotype, det. and coll. F. Emerson, Leopoldville, Belgian Congo, 14. VI. Silvestri, comp. A. Emerson, Colonia, Argentina, 1948. X. 1900. 105. Apicotermes angustatus Sjdstedt, worker, 86. Amphidotermes basidens (Sjostedt), worker, topotype, det. A. Emerson, Kasai, Belgian cotype, from type colony, det. Y. Sjostedt, Bis- Congo, coll. Luja, no. 59. marckburg, Africa, coll. Conradt. 106. Crenetermes albotarsalis (Sj;stedt), imago, 87. Globitermes sulphureus (Haviland), worker, cotype, det. Y. Sj6stedt, Kribi, Cameroon, coll. metatype, det. and comp. A. Emerson, Phoc-Son, Morgen, XII. 1888. Annam, coll. H. Fruhstorfer. 107. Thoracotermes macrothorax (Sjostedt), 88. Prohamitermes mirabilis (Haviland), worker, autotype, det. Y. Sjostedt, Gold Coast, worker, cotype, det. and coll. G. D. Haviland, coll. W. H. Patterson, 1926. Mt. Lambir, Sarawak, Borneo. 108. Apilitermes longiceps (Sjostedt), worker, 89. Cephalotermes rectangularis (Sjdstedt), cotype, det. Y. Sjostedt, Victoria, Cameroon, coil. worker, det. and coll. F. Silvestri, metatype, Buchholz. comp. A. Emerson, Victoria, Cameroon, I. 1913. 109. Megagnathotermes notandus Silvestri, 90. Cylindrotermes nordenskioldi Holmgren, worker, cotype, det. and coll. F. Silvestri, Mamon, worker, det. N. Holmgren, Trich, Bolivia. French Guinea, 25. VIII. 1912. 91. Labritermes buttel-reepeni Holmgren, 110. Cubitermes bilobatus (Haviland), worker, worker, det. N. Holmgren, redet. A. Emerson, det. and coll. C. Fuller, redet. and comp. A. Tandjong Slamat, east Sumatra, coll. H. v. Emerson, Pretoria, Transvaal, 12. X. 1920. Buttel-Reepen. 111. Procubitermes arboricola (Sj6stedt), 84 BULLETIN AMERICAN MUSEUM OF NATURAL HISTORY VOL. 95 worker, autotype, det. Y. Sjostedt, Belgian Congo, coll. A. Emerson, Kartabo, British Guiana, 5. V. coll. Laman. 1924. 112. Lepidotermes pretoriensis (Sjostedt), 127. Angulitermes frontalis Silvestri, worker, worker, paratype, det. Y. Sjostedt, Kimberley, paratype, det. F. Silvestri, Kalahari, South Africa, South Africa, coll. H. Power, VII. 1913. coll. L. Schultze. 113. Noditermes sinuosus (Silvestri), worker, 128. Crepititermes verruculosus Emerson, imago, metatype, det. and comp. A. Emerson, Sierra metatype, topotype, det., comp., and coll. A. Leone, coll. F. A. Squire, 10. III. 1918. Emerson, Kartabo, British Guiana, 9. IV. 1924. 114. Unguitermes bidentatus (Silvestri), worker, 129. Cavitermes tuberosus Emerson, imago, cotype, det. and coll. F. Silvestri, Victoria, Cam- metatype, autotype, det. and coll. A. M. Adam- eroon, 6. I. 1913. son, redet. and comp. A. Emerson, Trinidad, 115. Euchilotermes tensus Silvestri, worker, co- British West Indies, 25. VI. 1936. type, det. and coll. F. Silvestri, Mamon, French 130. Paracapritermes primus Hill, worker, para- Guinea, 26. VIII. 1912. type from type colony, det. G. F. Hill, Mt. Mol- 116. Ophiotermes grandilabius Emerson, worker, loy, north Queensland, Australia, coll. F. H. Tay- paratype, from type colony, det. A. Emerson, lor, III. 1927. Bipindi, Cameroon, coll. G. Zenker, 1920. 131. Quasitermes caprinus Emerson, worker, 117. Spinitermes nigrostomus Holmgren, imago, paratype from type colony, det. A. Emerson, metatype, det. and comp. A. Emerson, Couran- Madagascar, coll. H. Kirby, no. T-4463. tyne River, Dutch Guiana, coll. N. Weber, 11. 132. Mirocapritermes connectus Holmgren, VII. 1936. worker, cotype, det. N. Holmgren, Tandjong 118. Tuberculitermes bycanistes var. guineensis Slamat, East Sumatra, coll. H. v. Buttel-Reepen, Silvestri, worker, cotype, det. and coll. F. Sil- no. 431. vestri, Kindia, French Guinea, 21. VIII. 1912. 133. Cornicapritermes mucronatus Emerson, 119. Basidentitermes auriviliii Sjostedt, worker, worker, paratype, det. A. Emerson, British det. A. Emerson, Bujishu, Uganda, coll. H. Har- Guiana, coll. E. R. Blake, X. 1938. greaves, I. 1930. 134. Homallotermes penangi (Holmgren), 120. Fastigitermes jucundus Sj6stedt, worker, worker, cotype, det. N. Holmgren, redet. A. metatype, det., coil., and comp. A. Emerson, Emerson, Penang, Malacca, coll. H. v. Buttel- Camp Puttnam, Epulu, Belgian Congo, 23. V. Reepen, no. 132a. 1948. 135. Pericapritermes urgens Silvestri, worker, 121. Proboscitermes tubuliferus Sjostedt, autotype, metatype, det. F. Silvestri, comp. A. worker, metatype, det. and coll. F. Silvestri, Emerson, Aburi, Gold Coast, 18. I. 1913. comp. A. Emerson, Victoria, Cameroon, 6. I. 1913. 136. Protocapritermes krisiformis (Froggatt) 122. Orthotermes mansuetus (Sjbstedt), imago, imago, metatype, det. G. F. Hill, comp. A. Emer- cotype, det. Y. Sj6stedt, Mukimbungu, Belgian son, Australia, I. 1939. Congo, coll. Laman, 16. XI. 1904. 137. Capritermes capricornis (Wasmann), 123. Orthognathotermes wheelers Snyder, imago, worker, metatype, det. and comp. A. Emerson, det. and coll. A. Emerson, La Jaqua Hunting Madagascar, coll. H. Kirby, 27. V. 1935, no. Club, Republic of Panama, 26. V. 1935. T-4347. 124. Promirotermes holmgreni Silvestri, worker, 138. Procapritermes setiger Haviland, worker, metatype, worker det. and comp. A. Emerson, cotype, det. and coll. G. D. Haviland, Sarawak, Accra, Gold Coast, coll. A. W. J. Pmeroy, 31. V. Borneo. 1926. 139. Pseudocapritermes silvaticus Kemner, 125. Spicotermes brevicarinatus Emerson, worker, paratype, det. and coll. N. A. 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